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diff --git a/old/60765-h/60765-h.htm b/old/60765-h/60765-h.htm deleted file mode 100644 index e264e54..0000000 --- a/old/60765-h/60765-h.htm +++ /dev/null @@ -1,9917 +0,0 @@ -<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Strict//EN" - "http://www.w3.org/TR/xhtml1/DTD/xhtml1-strict.dtd"> -<html xmlns="http://www.w3.org/1999/xhtml" xml:lang="en" lang="en"> - <head> - <meta http-equiv="Content-Type" content="text/html;charset=utf-8" /> - <meta http-equiv="Content-Style-Type" content="text/css" /> - <title> - The Project Gutenberg eBook of The Young Mechanic, by James Lukin. - </title> - - <link rel="coverpage" href="images/cover.jpg" /> - -<style type="text/css"> - -a { - text-decoration: none; -} - -body { - margin-left: 10%; - margin-right: 10%; -} - -h1,h2,h3 { - text-align: center; - clear: both; -} - -hr { - margin-top: 2em; - margin-bottom: 2em; - clear: both; - width: 65%; - margin-left: 17.5%; - margin-right: 17.5%; -} - -ul { - list-style-type: none; -} - -li { - margin-top: .5em; - padding-left: 2em; - text-indent: -2em; -} - -p { - margin-top: 0.5em; - text-align: justify; - margin-bottom: 0.5em; - text-indent: 1em; -} - -p.dropcap { - text-indent: 0em; -} - -p.dropcap:first-letter { - color: transparent; - visibility: hidden; - margin-left: -0.9em; -} - -img.dropcap { - float: left; - margin: 0 0.5em 0 0; -} - -table { - margin: 1em auto 1em auto; - max-width: 30em; - border-collapse: collapse; -} - -td { - padding-left: 2.25em; - padding-right: 0.25em; - vertical-align: top; - text-indent: -2em; - text-align: justify; -} - -.tdr { - vertical-align: bottom; - text-align: right; -} - -.borders { - border-top: thin solid black; - border-bottom: thin solid black; - padding: 0.25em; - margin: auto; - max-width: 30em; -} - -.caption { - text-align: center; - margin-bottom: 1em; - font-size: 90%; - text-indent: 0em; -} - -.center { - text-align: center; - text-indent: 0em; -} - -.ditto { - margin-left: 2em; - margin-right: 2em; -} - -.figcenter { - margin: auto; - text-align: center; -} - -.footnotes { - margin-top: 1em; - border: dashed 1px; -} - -.footnote { - margin-left: 10%; - margin-right: 10%; - font-size: 0.9em; -} - -.footnote .label { - position: absolute; - right: 84%; - text-align: right; -} - -.fnanchor { - vertical-align: super; - font-size: .8em; - text-decoration: none; -} - -.hanging p { - padding-left: 2em; - text-indent: -2em; - font-size: 90%; -} - -.larger { - font-size: 150%; -} - -.pagenum { - position: absolute; - right: 4%; - font-size: smaller; - text-align: right; - font-style: normal; -} - -.poetry-container { - text-align: center; - margin: 1em; -} - -.poetry { - display: inline-block; - text-align: left; -} - -.poetry .stanza { - margin: 1em 0em 1em 0em; -} - -.poetry .verse { - text-indent: -3em; - padding-left: 3em; -} - -.poetry .indent1 { - text-indent: -2em; -} - -.right { - text-align: right; -} - -.smaller { - font-size: 80%; -} - -.smcap { - font-variant: small-caps; - font-style: normal; -} - -.smcapuc { - font-variant: small-caps; - font-style: normal; - text-transform: lowercase; -} - -.titlepage { - text-align: center; - margin-top: 3em; - text-indent: 0em; -} - -@media handheld { - -img { - max-width: 100%; - width: auto; - height: auto; -} - -.poetry { - display: block; - margin-left: 1.5em; -} - -img.dropcap { - display: none; -} - -p.dropcap:first-letter { - color: inherit; - visibility: visible; - margin-left: 0; -} -} - </style> - </head> -<body> - - -<pre> - -The Project Gutenberg EBook of The Young Mechanic, by James Lukin - -This eBook is for the use of anyone anywhere in the United States and most -other parts of the world at no cost and with almost no restrictions -whatsoever. You may copy it, give it away or re-use it under the terms of -the Project Gutenberg License included with this eBook or online at -www.gutenberg.org. If you are not located in the United States, you'll have -to check the laws of the country where you are located before using this ebook. - -Title: The Young Mechanic - -Author: James Lukin - -Release Date: November 22, 2019 [EBook #60765] - -Language: English - -Character set encoding: UTF-8 - -*** START OF THIS PROJECT GUTENBERG EBOOK THE YOUNG MECHANIC *** - - - - -Produced by Chris Curnow and the Online Distributed -Proofreading Team at http://www.pgdp.net (This file was -produced from images generously made available by The -Internet Archive) - - - - - - -</pre> - - -<h1><span class="smaller">THE</span><br /> -YOUNG MECHANIC</h1> - -<p class="titlepage"><span class="smaller">CONTAINING</span><br /> -<i>DIRECTIONS FOR THE USE OF ALL KINDS OF TOOLS</i>,<br /> -<span class="smaller">AND FOR THE</span><br /> -<i>CONSTRUCTION OF STEAM ENGINES AND<br /> -MECHANICAL MODELS</i>,<br /> -<span class="smaller">INCLUDING</span><br /> -<i>THE ART OF TURNING IN WOOD AND METAL</i>.</p> - -<p class="titlepage"><span class="smaller">BY THE</span><br /> -AUTHOR OF “THE LATHE AND ITS USES”<br /> -“THE AMATEUR MECHANIC’S WORKSHOP,” &c.</p> - -<p class="titlepage"><i>FROM THE ENGLISH EDITION, WITH CORRECTIONS, &c.</i></p> - -<p class="titlepage">G. P. PUTNAM’S SONS</p> - -<p class="center smaller">NEW YORK<br /> -27 WEST TWENTY-THIRD ST.</p> - -<p class="center smaller">LONDON<br /> -24 BEDFORD ST., STRAND</p> - -<p class="center">The Knickerbocker Press</p> - -<p class="center">1896</p> - -<div class="borders"> - -<p class="center">Entered according to Act of Congress, in the year 1871, by<br /> -G. P. PUTNAM & SONS,<br /> -in the Office of the Librarian of Congress at Washington.</p> - -</div> - -<hr /> - -<p><span class="pagenum"><a name="Page_i" id="Page_i">[i]</a></span></p> - -<h2>INTRODUCTION TO THE AMERICAN EDITION.</h2> - -<p>In presenting the American edition of this little work to the -public, we believe we are supplying a want that has long been -felt by the Young Mechanics of this country, and many others -who desire to become versed in the practical use of tools. We -know of no other book published in this country or England, in -which the method of using tools is so clearly explained; and -although written more especially for boys and beginners, it contains -much information that will be of great value to the practical -mechanic. The author is evidently thoroughly acquainted with -his subject, and understands how to communicate his ideas in a -simple and concise manner.</p> - -<p>The first six chapters are devoted to the description of Tools -for working wood and the manner of using them, beginning with -the simplest operations, requiring but few tools, and gradually -leading on to the more difficult, giving examples of all the -methods of joining and finishing work that are in common use -among good workmen, and in this connection we would like to -call attention to the small number of tools the author requires -for performing all these different operations, the idea among -amateurs and boys generally being, that if you only have tools -enough you can make anything. This is not so, and if the beginner -will follow the advice of the author, and buy a few good -tools, and learn the use of them thoroughly, and gradually add -to his stock as his knowledge of their use increases, he will find -it greatly to his advantage.</p> - -<p>The next five chapters relate to the lathe, and the art of turning. -The author follows the same plan as in the first part of the -book, and gives more practical information in these few pages -than we have seen in any other book on the subject, most of them -being written apparently for finished mechanics, and not for -beginners. The Art of Turning as an amusement, is beginning -to attract considerable attention in this country, but not so much<span class="pagenum"><a name="Page_ii" id="Page_ii">[ii]</a></span> -as it deserves and would obtain, if it were more generally known -how many beautiful and useful articles can be produced in the -lathe. The expense of the necessary tools has deterred many -from attempting to learn this branch of mechanics; but we believe -if any one has the time and patience to devote to the work, they -will never have occasion to regret the money spent for this -purpose.</p> - -<p>The last four chapters contain practical instruction in model-making -and working in metal. This part of the book we would -particularly recommend to inventors who desire to make their own -models, as it contains information in regard to files, drills, and -the various small tools used on metal, and also directions for laying -out work, which are invaluable to a novice in such operations, -and will save him much time and trouble.</p> - -<p>As this book was originally published in London, where the -facilities for getting many kinds of small tools are better than in -this country, perhaps a little advice as to the best way of getting -such tools as may be required will not be out of place. In most -of the large Hardware Stores, carpenters’ tools will be found, put -up in chests, at prices varying from five to fifty dollars or more; -but we should not advise the amateur to buy any of these, as the -quality of the tools is not always reliable, and as they are usually -fitted up to make as much show as possible for the money, they -contain many tools which are of very little use. The best way -is to make a list of the tools required, and select them for yourself. -The most important thing is to have the Cutting tools of -good quality. We give below the names of some of the best -makers of tools; if you purchase any of these, you may be sure -of the quality.</p> - -<ul> -<li>On Saws,—<span class="smcap">Henry Disston</span>, <span class="smcap">Groves & Son</span>.</li> -<li>On Chisels and Gouges,—<span class="smcap">Buck Bros.</span>, <span class="smcap">Moulson Bros.</span></li> -<li>On Plane Irons,—<span class="smcap">Moulson Bros.</span>, <span class="smcap">Wm. Butcher</span>.</li> -<li>On Files,—<span class="smcap">P. S. Stubs</span>, <span class="smcap">Greaves & Son</span>, <span class="smcap">Earl & Co.</span></li> -<li>On Rules and Squares,—<span class="smcap">Stanley Rule and Level Co.</span></li> -</ul> - -<p><span class="pagenum"><a name="Page_iii" id="Page_iii">[iii]</a></span></p> - -<p>If you live in the City, you will probably find no difficulty in -procuring some of the above makes; but if you cannot find them -there are some others that are good, and you must rely somewhat -on the dealer. In regard to the probable cost of the tools, a set -such as is described on pages 29 and 30, would cost from fifteen -to twenty dollars.</p> - -<p>Of Foot Lathes, the following are some of the makers:</p> - -<ul> -<li><span class="smcap">N. H. Baldwin</span>, Laconia, N. H.</li> -<li><span class="smcap">Goodnow & Wightman</span>, Boston, Mass.</li> -<li><span class="smcap">American Tool Co.</span> <span class="ditto">”</span> <span class="ditto">”</span></li> -<li><span class="smcap">G. L. Cady</span>, Lowell, Mass.</li> -<li><span class="smcap">Exeter Machine Co.</span>, Exeter, N. H.</li> -<li><span class="smcap">Jas. Stewart’s Sons</span>, New York.</li> -</ul> - -<p>From some of the above the amateur will probably be able to -select a Lathe to suit him in size and price. The lowest price at -which a serviceable lathe can be bought is about forty dollars -this is without tools or chucks. About fifteen dollars more would -be required for these. Lathes can be bought from this price up -to hundreds of dollars, according to the style of lathe and the -number of chucks, but of course the beginner would not need -an expensive lathe, and seventy-five to one hundred dollars would -buy a lathe and tools suitable for all kinds of small work in -wood, ivory, or metal.</p> - -<p class="smaller">This volume being an exact reprint of the English edition, it may be -well to explain that the material called <i>Deal</i> in England is much the same -as our <i>Pine</i>. The article called in England a “Carrier,” is with us called -a <i>dog</i> (see pp. 112, 114, 115). Articles priced in English currency would -cost here now about 35 cents to the English shilling, or $7 per £ stg.</p> - -<hr /> - -<p><span class="pagenum"><a name="Page_iv" id="Page_iv">[iv]</a></span></p> - -<div class="figcenter" style="width: 500px;"> -<img src="images/header1.jpg" width="500" height="110" alt="" /> -</div> - -<h2><span class="smcap">Preface.</span></h2> - -<div> -<img class="dropcap" src="images/dropcap-o.jpg" width="100" height="120" alt="" /> -</div> - -<p class="dropcap">Of all people in the world who must not be -neglected are, first and foremost, “Our Boys,” -and, of all boys, <i>mechanical boys</i> deserve a very -high place in our estimation. Whatever others -may be, these, at any rate, are possessed of sound heads, -and willing hands. Therefore, to help these to carry out -their designs, appears to be a special duty of those who, -once mechanical boys themselves, have lived to become the -progenitors of others. In fulfilment of this very duty I -have taken up the pen, and with special reference to <i>young</i> -mechanics, but without entirely forgetting those of maturer -growth, I have thrown together a few hints upon that -absorbing question, “How to make and how to use?” In -doing this, I have endeavoured to carry out the plan of<span class="pagenum"><a name="Page_v" id="Page_v">[v]</a></span> -<i>small beginnings</i>, going from the simplest and easiest to the -more complicated and difficult work, although here and -there, of sheer necessity, a somewhat different order has been -observed. The workshops of King’s College School prove -the capabilities of boys to do high-class mechanical work -when their efforts are rightly directed by a master’s hand. -Where the latter cannot be obtained, guide-books must, -however insufficiently, take his place; but whether instruction -in mechanical art be oral or otherwise, practice and -perseverance are the secrets of success.</p> - -<div class="poetry-container"> -<div class="poetry"> -<div class="verse">“Qui studet optatam cursu contingere metam,</div> -<div class="verse">Multa tulit fecitque puer; sudavit et alsit.”</div> -</div> -</div> - -<div class="figcenter" style="width: 150px;"> -<img src="images/footer1.jpg" width="150" height="125" alt="" /> -</div> - -<hr /> - -<div class="figcenter" style="width: 500px;"> -<img src="images/header2.jpg" width="500" height="110" alt="" /> -</div> - -<h2><span class="smcap">Contents.</span></h2> - -<table summary="Contents"> - <tr> - <td class="right smaller">CHAP.</td> - <td></td> - <td class="tdr smaller">PAGE</td> - </tr> - <tr> - <td class="right">I.</td> - <td>INTRODUCTORY,</td> - <td class="tdr"><a href="#CHAPTER_I">1</a></td> - </tr> - <tr> - <td class="right">II.</td> - <td>HOW TO MAKE A CAGE,</td> - <td class="tdr"><a href="#CHAPTER_II">15</a></td> - </tr> - <tr> - <td class="right">III.</td> - <td>MORTICE AND TENON JOINTING,</td> - <td class="tdr"><a href="#CHAPTER_III">29</a></td> - </tr> - <tr> - <td class="right">IV.</td> - <td>HOW TO MAKE A TABLE,</td> - <td class="tdr"><a href="#CHAPTER_IV">49</a></td> - </tr> - <tr> - <td class="right">V.</td> - <td>DOVETAILING AND MITRING,</td> - <td class="tdr"><a href="#CHAPTER_V">66</a></td> - </tr> - <tr> - <td class="right">VI.</td> - <td>REBATING, TONGUEING, AND GROOVING,</td> - <td class="tdr"><a href="#CHAPTER_VI">89</a></td> - </tr> - <tr> - <td class="right">VII.</td> - <td>THE YOUNG MECHANIC AT THE LATHE,</td> - <td class="tdr"><a href="#CHAPTER_VII">103</a></td> - </tr> - <tr> - <td class="right">VIII.</td> - <td>ON WOODS AND MATERIALS FOR TURNING,</td> - <td class="tdr"><a href="#CHAPTER_VIII">122</a></td> - </tr> - <tr> - <td class="right">IX.</td> - <td>SHARPENING AND SETTING TOOLS,</td> - <td class="tdr"><a href="#CHAPTER_IX">144</a></td> - </tr> - <tr> - <td class="right">X.</td> - <td>HAND-TURNING IN WOOD,</td> - <td class="tdr"><a href="#CHAPTER_X">163</a></td> - </tr> - <tr> - <td class="right">XI.</td> - <td>HARD-WOOD TURNING,</td> - <td class="tdr"><a href="#CHAPTER_XI">203</a></td> - </tr> - <tr> - <td class="right">XII.</td> - <td>HOW TO MAKE A STEAM-ENGINE,</td> - <td class="tdr"><a href="#CHAPTER_XII">226</a></td> - </tr> - <tr> - <td class="right">XIII.</td> - <td>WATT’S ENGINE,</td> - <td class="tdr"><a href="#CHAPTER_XIII">264</a></td> - </tr> - <tr> - <td class="right">XIV.</td> - <td>HOW TO MAKE AN ENGINE,</td> - <td class="tdr"><a href="#CHAPTER_XIV">281</a></td> - </tr> - <tr> - <td class="right">XV.</td> - <td>HARDENING AND TEMPERING TOOLS,</td> - <td class="tdr"><a href="#CHAPTER_XV">325</a></td> - </tr> -</table> - -<hr /> - -<p><span class="pagenum"><a name="Page_1" id="Page_1">[1]</a></span></p> - -<div class="figcenter" style="width: 500px;"> -<img src="images/header3.jpg" width="500" height="110" alt="" /> -</div> - -<h2 id="CHAPTER_I"><span class="smcap">Chapter I.</span></h2> - -<div> -<img class="dropcap" src="images/dropcap-t.jpg" width="100" height="120" alt="" /> -</div> - -<p class="dropcap">There never was a time when a taste for practical -mechanics was so general among boys as it is -now, in this year of grace 1870. There are -comparatively few homes in which evidences of -this hobby are not apparent in every odd nook and corner, -in the shape of carpenter’s tools, not always in first-rate -condition, nor by any means generally in their proper -places. A saw here, a hammer there, a gimlet, bradawl, -or chisel elsewhere.</p> - -<p>This probably results from the giant strides which have -been made of late years in mechanical enterprise, and the -introduction of machinery into every department, as a means -of saving labour and facilitating the production of the -various necessaries of life.</p> - -<p>Man is an imitative animal, and in this as in other things -“the child is father to the man;” and hence it comes to -pass that the boy whose eyes are continually resting upon -machinery of one sort or another (agricultural implements,<span class="pagenum"><a name="Page_2" id="Page_2">[2]</a></span> -if a villager; engines for planing, sawing, turning, and so -forth, if resident in a town) sooner or later feels an innate -desire to construct models of these gigantic mechanical -labourers, by whose incessant but unfelt toil our several -daily needs are so cheaply and plentifully supplied.</p> - -<p>Even if the youthful mind does not always display -highly-developed inventive faculties, there is very generally -manifested a desire of personally constructing some -one or more of those articles which conduce to the gratification -of a particular hobby. If the boy has a taste for -natural history, cases and cabinets will be made, for the -reception of eggs, butterflies, and insects, or to contain -stuffed specimens of animals and birds. If he has within -him the elements of a sailor, his ingenuity will be -exercised upon model boats and ships. If fond of dumb -pets, rabbit hutches, dove-cots, or cages will afford him -opportunities for the exercise of his constructive powers, -and thus the young mechanic frequently lays the foundation -of future eminence in that particular line of life to -which his tastes naturally lead him.</p> - -<p>There are few boyish hobbies in which assistance has -not of late years been given by instruction books and guides -of a high degree of excellence—natural history, botany, -gardening, rearing and breeding all manner of pets—to -each of these, well-written volumes have been devoted -by able and experienced writers, but mechanical and<span class="pagenum"><a name="Page_3" id="Page_3">[3]</a></span> -constructive art has been somewhat neglected. Here and -there, in periodical magazines, a few pages are dedicated -to the subject, but no book about practical mechanics, -written expressly for boys, has yet appeared.</p> - -<p>The author of the present volume, himself father of four -lads, <i>all</i> of whom in turn occasionally try their hands at -this kind of work, and who has himself for many years -practised the mechanical arts of carpentry, turning, and -model-making, hopes that the hints contained herein may -prove valuable to those young friends whom he now addresses. -Some of the following chapters will be arranged -for very little boys, some for those who are older, while it -is believed that other parts of the work may not prove -altogether useless to those who have dropped jacket and -knickerbockers and rejoice in the vigour of manhood. -Thus the little boy, who receives the book as a present, -will find it a fast and faithful friend as his years, and, we -trust, knowledge and bodily powers increase.</p> - -<p>“<i>Small boys need few tools, but much perseverance.</i>” -Let this be their motto, as it will stand them in good -stead. A pocket-knife, gimlet, hammer, and a few nails -will generally serve their purpose; but there is one other -tool, namely, a square, which is of great importance, and -of which it is well to learn the use as early as possible. -A small saw and a bradawl may also be added to the list, -and likewise a chisel half an inch wide. Thus equipped,<span class="pagenum"><a name="Page_4" id="Page_4">[4]</a></span> -a very youthful carpenter can do a good deal, and, let me -tell him, a good deal has been often done without even -this moderate supply of tools. It must be taken for -granted that the knife and chisel are sharp, because blunt -tools make bad work, and by far the best plan for small -boys is to get some friend to sharpen them when blunt, as -the operation is not easy and requires practice. It is a very -foolish plan to try and work with a blunt knife, for the -fingers are just as much in danger; and a boy who intends -to learn how to use tools must learn at the commencement -to use them with due care, so as not to damage himself.</p> - -<p>There are small boxes of tools sold, containing generally -a wooden mallet, saw, plane, chisel, and gimlet, at -about 3s. 6d. or even 5s. Such a box is simply useless. -The tools are of iron—will not take a good edge, and are -generally disposed to bend and twist. Avoid these, and -buy, or get a friend to buy, those I have named, of good -quality, and be sure to take care of them, for which purpose -you may try your hand at making a box. For this -purpose, you will require some thin board (half-inch thick) -planed on both sides. (The carpenter will prepare this for -you.) Let us see how much you will need. Measure your -longest tool, the chisel or saw, if the latter is quite a small -one fit to go into a little box; if not, it can be hung on a -nail, and you can make your box to contain your knife -and chisel and gimlets. I daresay if the box is 9 inches<span class="pagenum"><a name="Page_5" id="Page_5">[5]</a></span> -long, 4 inches wide, and 3 inches deep, it will be large -enough to take these few tools, for I have just now measured -such a hammer and chisel as I have recommended, -and find them each about 9 inches in length. The top and -bottom of a box should project a little all round, so that -you will want them about an inch and a half wider and -longer, which will also allow for the thickness of the wood; -for you must remember we have given the size of the box -<i>inside</i>. To make this clear, I shall here give a plan of the -bottom of the box (Fig. 1).</p> - -<div class="figcenter" style="width: 300px;" id="fig1"> -<img src="images/figure1.jpg" width="300" height="150" alt="" /> -<p class="caption">Fig. 1.</p> -</div> - -<div class="figcenter" style="width: 300px;" id="fig2"> -<img src="images/figure2.jpg" width="300" height="150" alt="" /> -<p class="caption">Fig. 2.</p> -</div> - -<div class="figcenter" style="width: 600px;" id="fig3"> -<img src="images/figure3.jpg" width="600" height="100" alt="" /> -<p class="caption">Fig. 3.</p> -</div> - -<p>It is 10½ inches long, and 5½ inches wide. The broad -black line shows where the edges of the sides and ends will -come, these being half an inch thick, so that there is a -quarter of an inch all round the outside as a border. -Reckon across and you will understand this better. A -quarter of an inch outside, half an inch for the black line -(equals three-quarters of an inch), 4 inches for the <i>inside</i><span class="pagenum"><a name="Page_6" id="Page_6">[6]</a></span> -width, half an inch again for the black line, and a quarter -of an inch outside as before,—altogether making 5½ inches. -Now reckon the length. A quarter-inch border, half an -inch for the black line, 9 inches inside, half inch for the -second black line, and another quarter outside—making -10½ inches. You require, therefore, two boards 10½ inches -long and 4½ wide for the top and bottom. Now the two -long sides and the ends are to be 3 inches wide to form -the depth of the box, and here you want no extra <i>width</i>, -but as the <i>inside</i> of your box is to be 9 inches long, and -the sides are usually nailed over the ends, like Fig. 2, -where I have shown them put together, you see that you -must have the <i>sides</i> as much longer than 9 inches as will -allow them to lap over the ends; that is, half an inch at -each end where I have made them black, or altogether, one -inch; so that you will want two pieces 10 inches long and -3 wide. The ends will be also 3 inches wide and 4 inches -the other way, and here no additional size is needed. Now, -the usual way to cut the sides is to get a narrow strip -of board of the required width and thickness, and long -enough to make both the sides and ends, just such a piece -as Fig. 3, on which are marked the lines where it will have -to be cut across, and you will easily perceive that you require -28 inches in length and 3 in width.</p> - -<p>But you must understand that when you cut with a saw -you waste a little of the wood, which falls in the shape of<span class="pagenum"><a name="Page_7" id="Page_7">[7]</a></span> -sawdust, and so if you did not allow for this, your box -would be too small. The waste depends on the thickness -of the edge of the saw, where you will, if you examine it, -see that the teeth spread out right and left to prevent it -from sticking fast as it is used. Probably, you would -waste three-eighths of an inch, which is nearly half an inch -in cutting off the pieces, so that instead of a piece exactly -28 inches long, you must have it 28½ inches, or even a -little more.</p> - -<p>I want you to understand all this before you set to work, -even though at first you may get a carpenter to measure -and cut it for you; because most small boys take no trouble -of this kind, and consequently they are sure to make their -boxes too large or too small, and they look very bad when -done. However, as I said before, I expect my young -readers to understand what they are about, and they must -set out their work carefully, or they will never get on so as -to be able to make good use of the later chapters of this -book. A carpenter’s rule is made like this (Fig. 4).</p> - -<div class="figcenter" style="width: 400px;" id="fig4"> -<img src="images/figure4.jpg" width="400" height="185" alt="" /> -<p class="caption">Fig. 4.</p> -</div> - -<p><span class="pagenum"><a name="Page_8" id="Page_8">[8]</a></span></p> - -<p>Sometimes there is a brass slide, to add to its length -when necessary, and sometimes it is hinged so as to fold up -again. If you want one for your box, you can get it so -made, when it will go in nicely. It is 2 feet long—1 foot -on each side of the central joint. A foot is 12 inches; the -whole rule, therefore, is 24 inches. Now, you will see that -each of these inches is divided by short lines into eight -equal parts, called eighths; at the second, the line is rather -longer, this being a quarter of an inch; at the fourth, there -is a still longer line, this being the half-inch; then comes -another eighth, then the three-quarters, another eighth, and -the inch is made up,—eight-eighths being equal to one -whole inch. Very likely you will find one <i>edge</i> of the rule, -or sometimes only one <i>inch</i>, divided into smaller parts, -which are sixteenths, or half-eighths; and sometimes, but -not very often, divisions still smaller are used, which are -half-sixteenths, or thirty-seconds, because thirty-two such -divisions make the complete inch. Three feet make one -yard, but carpenters always reckon by the foot and inch, -and by eighths and sixteenths of an inch. In some trades -the inch is divided into a <i>hundred</i> parts, and work is measured -up and fitted so carefully, that it would be considered -faulty if a mistake of less than a <i>thousandth</i> of an inch were -made; but you will not yet understand how it is possible -even to <i>measure</i> so very small a quantity. You should -certainly learn and understand how to measure with a<span class="pagenum"><a name="Page_9" id="Page_9">[9]</a></span> -common two-foot rule, and when you can add one to your -box of tools, do so.</p> - -<p>Now, let us examine the tool called a square, without -which the marks could not readily be drawn as a guide for -the saw, where the strip of board is to be cut to make the -sides and ends of the proposed box. Here is a drawing of -one (Fig. 5).</p> - -<div class="figcenter" style="width: 400px;" id="fig5"> -<img src="images/figure5.jpg" width="400" height="300" alt="" /> -<p class="caption">Fig. 5.</p> -</div> - -<div class="figcenter" style="width: 400px;" id="fig6"> -<img src="images/figure6.jpg" width="400" height="200" alt="" /> -<p class="caption">Fig. 6.</p> -</div> - -<p>It is a handle and a blade, like a knife half opened, the one -being fixed exactly square, or at right angles with the -other. The blade is thinner than the handle, and when -the latter is placed as in Fig. 6, a line marked across the -board against the edge of the blade will be, of course, -square to the side, so that when cut off, the piece will be -like the end of Fig. 6. This is not the shape which the -sides of boxes generally have when made by small boys, -because they have not a square, and do not know how to -work properly. Nevertheless, if <i>one</i> end of a board is cut -square, you might get the piece right by measuring the same<span class="pagenum"><a name="Page_10" id="Page_10">[10]</a></span> -distance on each side (say 10½ inches), and drawing a line -across from point to point, as a guide for the course of the -saw. But, then, as it is absolutely necessary that the end -of the board should be square to the side, to do this you -had better get a proper square at once, and learn how to -use it. You will, indeed, find this tool most necessary for -all kinds of work, and you will be quite unable to do without -it, even though you only have, besides, a knife and -gimlet.</p> - -<p>Now, if you want to cut off a piece of board with the saw, -you must <i>never cut out the line you have marked as a guide -by the help of your square</i>, because if you do, you will get -the piece too short, owing to the width of the saw-cut -which I explained before. Cut, therefore, <i>just</i> beyond it, -leaving it upon the piece you are going to use for the side -of your box, or other article. At first, you will find it -difficult to saw neatly and close to the line, but you will -get used to it very soon; and if the saw does not go quite -straight, you can trim the piece with a sharp knife neatly -up to the line, which you see you could not do if you cut -out that line by sawing exactly upon it. All these directions -in little matters are very important, because you will -find that, by attending to them, you will work well, and -the various things you make will look neat and trim, and -be fit to show to your friends.</p> - -<p>Now, let us go on with the box, which was laid down<span class="pagenum"><a name="Page_11" id="Page_11">[11]</a></span> -just to allow a little explanation about the carpenter’s rule -and square. I shall suppose you to have cut off all the -pieces quite squarely and neat, and that the <i>edges</i> are also -square to the sides, which you must take care to insure by -keeping the blade of the saw upright when you use it. It -is a good plan to measure and mark <i>both</i> sides of your -board for this purpose, and to mark the edges from one of -these lines to the other. You will then have guide-marks -all round, and, by keeping close to these, you will be sure -to cut your work truly. It would not so much signify if -the long sides were cut a trifle <i>too</i> long, as I shall explain -presently; but the <i>ends</i> must be square and true to measure, -4 inches by 3 inches. You must now proceed to nail -them together. This must be done with small <i>brads</i>, which -are fine nails, and which for the present purpose may be -one inch long. If your pieces are all exact to measure, -draw a pencil line across the two side pieces, a quarter of -an inch from the ends, by the help of the square, as if you -wanted to cut off a quarter of an inch at each of those -parts, and with your bradawl make two or three holes -(three will be best) along those lines. Do not make the -first and last too near the edges, or you will split the wood, -and spoil the box. Now set up one of the short pieces, and -place upon it the piece which you have bored holes in. If -you have a bench with a vice, you can screw up the short -piece into it; but it will stand up very well upon the<span class="pagenum"><a name="Page_12" id="Page_12">[12]</a></span> -bench if you have no vice. It is now in the position of -Fig. 7, C.</p> - -<div class="figcenter" style="width: 400px;" id="fig7"> -<img src="images/figure7.jpg" width="400" height="400" alt="" /> -<p class="caption">Fig. 7.</p> -</div> - -<p>Hold it thus, and run the bradawl a little way into the -lower piece, through the holes already made in the upper. -Drive a brad through the middle hole first, which will hold -it together, and then through the other two holes. If you -have been careful, you will find this corner square and -neat, and the wood not split in the least. Do the same -with the other short piece, and then nail on the long side -that is left. The frame of the box will now be complete.</p> - -<p>I told you a short time ago, that it would not much<span class="pagenum"><a name="Page_13" id="Page_13">[13]</a></span> -signify if the <i>sides</i> were cut too long. The reason is this: -Suppose B to be the side half an inch too long. You -would mark off 9 inches of the middle by two lines drawn -with the square as before, which would be the length of -the <i>inside</i> of the box; you would then place the inner -edges of the end pieces against these lines, and nail them -on like A, and afterwards neatly saw off the two pieces -which lap over these at each end. If the wood is likely to -split when the holes are made for the nails, or if the workman -is pressed for time, he very frequently does his work -in this way, and then cuts it off and planes it neatly. It is, -however, better to work as directed, only be sure to bore -holes carefully for the nails, so as never to split the wood.</p> - -<p>No very special directions are needed about putting on -the bottom. Leave all round an exactly even border of a -quarter of an inch, and after it is nailed, you may neatly -round off all its edges, to give it a finished appearance.</p> - -<p>The cover is, of course, to be attached by a pair of small -hinges. Brass hinges are the neatest, and when you buy -them, ask for screws to match. The hinges may be three-quarters -of an inch long, and they will be, when shut, -about half an inch wide, which is the size you need. Lay -them (shut up) upon the edge of the back, about two inches -from the ends, and with a hard pencil cut to a fine point, -or with the point of your bradawl, make a mark at each -end, as if you were measuring the length of the hinges on<span class="pagenum"><a name="Page_14" id="Page_14">[14]</a></span> -the edge of the box. Between these marks you have to cut -out pieces like Fig. 8, -which will be just the length of the hinges, and deep -enough to allow them, when shut up, to fit and lie even -with the top edge of the box. Open them, make holes -with the bradawl, and put in the screws. If you have not -a screwdriver, you can turn them with the end of an old -knife; but you may as well get a small screwdriver, for if -you intend to do good work, you will often use screws instead -of nails. Hinges are always screwed on. Now lay -the cover in place carefully, mark its position, so that you -have some sort of guide-line to direct you, and then by -laying the cover flat on the bench, and standing the (open) -box on its side, you can screw on the hinges upon the -cover. Round all the edges of the cover as you did the -bottom, but keep the edges of the <i>box</i> square and <i>sharp</i>; -and so you have now a really well-made little tool-chest. -A little brass hook and eye will do to fasten it, for a lock -is rather difficult for a small boy to put on.</p> - -<div class="figcenter" style="width: 400px;" id="fig8"> -<img src="images/figure8.jpg" width="400" height="175" alt="" /> -<p class="caption">Fig. 8.</p> -</div> - -<hr /> - -<p><span class="pagenum"><a name="Page_15" id="Page_15">[15]</a></span></p> - -<div class="figcenter" style="width: 500px;"> -<img src="images/header4.jpg" width="500" height="110" alt="" /> -</div> - -<h2 id="CHAPTER_II"><span class="smcap">Chapter II.</span></h2> - -<div> -<img class="dropcap" src="images/dropcap-t.jpg" width="100" height="120" alt="" /> -</div> - -<p class="dropcap">The method of constructing a simple box has been -given in the first chapter, because so many -other articles are made upon exactly similar -principles. The rules laid down comprise two -or three essential points, the neglect of which render the -ordinary carpentry of boys so essentially bad. Foremost -of these is <i>the use of the square</i>. There is no tool of more -general use in the hands of workmen in wood and metal, and -yet, generally speaking, either none at all, or a very faulty -one is added to the collection of tools ordinarily supplied to -boys. In the next place, I have insisted upon <i>accuracy in -measurement</i>. The carpenter’s rule is not at all difficult -for a young boy to understand; but even if he is not in -possession of such at his first attempts, he should always -be induced to work by measure of some kind. This causes -him of necessity to exercise his mind as well as his hands, -and teaches him to consider well at starting as to what he -must allow for thickness of wood, the difference between<span class="pagenum"><a name="Page_16" id="Page_16">[16]</a></span> -inside and outside measurement, and so forth; all this will -greatly conduce to his success, and consequently satisfaction -in his work, and will lessen the chances of his beginning -a number of articles and casting them aside unfinished—a -propensity too common in all boys.</p> - -<p>I shall now resume my directions in the first person, -which I think is the more easy method both for master -and pupil. The next specimen I propose, because it requires -even more care than a box, but is at the same time -perfectly within a boy’s powers, is a birdcage. Of these -there are such a number of varieties that it is difficult to -settle upon the best kind to begin upon. I think, however, -a wire cage will on the whole be the easiest to construct, -only you must take great care in boring holes in the -thin strips of wood, and, indeed, if you can get a birdcage-maker’s -awl besides the one you have, it will save both time -and trouble. It is not made round with a flat end, but is -three-cornered with a sharp point, so that it has three -edges, and when it is carefully used and twirled round and -round by the fingers in making holes, it will hardly ever -split even very thin strips and pieces of wood. However, -if you cannot get one never mind, you must use the common -bradawl according to directions here given.</p> - -<p>I shall suppose you now in possession of a carpenter’s -rule, and that you have carefully learned all I told you of -the inches and eighths, so that you may be able to measure<span class="pagenum"><a name="Page_17" id="Page_17">[17]</a></span> -and mark your work very truly. The front of the cage -is represented in Fig. 9, before the projecting roof-boards -have been put on.</p> - -<div class="figcenter" style="width: 400px;" id="fig9"> -<img src="images/figure9.jpg" width="400" height="275" alt="" /> -<p class="caption">Fig. 9.</p> -</div> - -<p>Here you see two upright strips at the corners, which shall -be 8 inches long. These are 12 inches apart, <i>outside</i> -measure. They are ⅜ (three-eighths) of an inch square, -and you must get them ready planed from the carpenter. -There will be four of them required, as they are at the four -corners of the cage; so that, as they are each 8 inches long, -you can get a strip 36 inches in length by three-eighths -wide, and this being 4 inches more than you need, will -allow for waste. At the lower part of the drawing, you see -the edge of the bottom board, which projects a little all -round. As the <i>outside</i> of the front pillars are 12 inches<span class="pagenum"><a name="Page_18" id="Page_18">[18]</a></span> -apart, this board may be 13 inches long, which will allow -a border of ½ an inch (half an inch), and it may be 8 inches -wide. It need not be <i>thicker</i> than a quarter of an inch. -A little above this board (say half an inch) is another -board from one pillar to another, which is to be 1¼ -inches wide and three-eighths of an inch thick. As the -pillars are also three-eighths thick, and their outside edges -12 inches apart, you must take 6/8 (six-eighths) of an inch -from 12 inches to find the length of this board.</p> - -<p>If you look at the divisions upon your rule, you will see -that six-eighths of an inch amounts to exactly ¾ (three -quarters), so that your board must be 11 inches and <i>one</i> -quarter long. This will also be the length of the board at -the top where it falls between the pillars, and this too -must be three-eighths thick.</p> - -<p>I shall now show you how to mark and cut this top -piece into the shape here sketched. Cut the board first -of all into an oblong, and mind that you mark it by -your square, so that the <i>ends shall be square to the -sides</i>. Let it be 2½ inches wide. Here it is (Fig. 10). -Measure a length of 6 inches from either end to the middle -at A, and make a mark at that place. Draw a line, C B, -one inch from the opposite side, the whole length of the -board, and mind you draw it correctly. You should measure -an inch at B, and at C, and then draw a line from one -point to the other along the edge of your rule. You must<span class="pagenum"><a name="Page_19" id="Page_19">[19]</a></span> -now draw two lines from the spot you marked at A to the -ends of this line (where you see the dotted lines). In -order to cut this piece, you must begin at A, not at B or -C, or else if the saw should stick you will be sure to split -off a strip right across the piece; but if it should stick -when you are cutting <i>from</i> A, you will only split off a bit -of one of the three-cornered outside pieces, which would -not signify at all.</p> - -<div class="figcenter" style="width: 400px;" id="fig10"> -<img src="images/figure10.jpg" width="400" height="150" alt="" /> -<p class="caption">Fig. 10.</p> -</div> - -<p>When you are sawing, be sure, as I told you before, not -to cut into the line you have marked, but saw just outside -it, so that the lines will be left upon the two sloping sides -of the board. You may <i>cut as close to it as you can</i>, but -you must not destroy it, and then you can with your knife -neatly shave off the rough edges which the saw has made, -until you have pared the wood quite neatly all along the -line. If you cut this line out, you will no longer have any -guide to work by. Cutting out guide lines is a very common -fault, not confined to small boys or big ones. You -will find it easy to pare this sloping side if you begin to<span class="pagenum"><a name="Page_20" id="Page_20">[20]</a></span> -work from A downwards to B and C, but you cannot cut it -in the other direction. A carpenter would, of course, run -his plane down the slope, and so will you by and by; but -planing is difficult, and it is better you should wait for a -time before you buy a plane; for, remember, those foolish -little things in boys’ tool-boxes are no use at all.</p> - -<p>You had better now prepare the holes into which the -wires are to be put as you see in the drawing. You can -use either iron wire or brass, but the first is cheapest. These -will have to be a quarter of an inch apart. Both the top -and bottom strips, you will remember, are 11¼ (eleven and -a quarter) inches long. Now, 11 inches will be 44 quarters, -and one more will be 45; but as the first hole must be -a quarter of an inch from the ends, you will find that 44 -holes will be required. Look at your rule and count this. -You must mark all these by little dots with a pencil on one -piece, and then laying the other upon it, mark the rest -exactly even with the first. Do this with great care, or -the wires will not stand upright when the cage is finished. -The space between the top and bottom pieces will be 5¼ -inches, so that if you allow the wires to enter a quarter of -an inch at the top and bottom, you will want 44 wires 5¾ -inches in length—you may say, 6 inches. You can have -them all cut and straightened for you, but if you have a -pair of pliers with cutting edges, you can do it yourself, -and it is almost necessary you should get a pair, or borrow<span class="pagenum"><a name="Page_21" id="Page_21">[21]</a></span> -them, if you intend to construct wire birdcages. You will -want a few less in each side of this cage, as it will not be -there so wide as it is in front. We shall presently see how -many it will require.</p> - -<p>You may put together the front of the cage at once and -set it aside, or proceed to cut out the rest of it. Generally -speaking, it is the best plan to cut out and prepare all -the main parts of your work before proceeding to fix them -in their respective places; but the front of such a cage as -I am describing, being complete in itself, you may do as -you like about it. We will begin with the wires. Insert -the ends one after the other in a row in one of the pieces, -laying it upon the bench, or fixing it on its edge in a vice, -but taking care not to bend them. When one piece is -thus stuck full of wires, lay it flat on its side, and put the -other piece in its place, and one by one insert into it the -other ends of the wires. A pair of pliers will help you -greatly in doing this. I daresay the two pieces of wood -will not be very parallel, but will be closer at one end than -at the other. This does not matter, because you will set -it right in nailing on the upright strips or corner pillars. -This, therefore, is the next thing you must do; and you -must have two brads top and bottom, each an inch long, -but as fine as you can get. Nail to the top board first, -and then place the other in position half an inch from the -bottom of the pillars. If you have no carpenter’s vice,<span class="pagenum"><a name="Page_22" id="Page_22">[22]</a></span> -you had better work with the front of the cage laid down -flat and near the right hand edge of the bench or table, so -that the pillar almost overlaps it. In this position, you -can bore the two holes and nail it together; but be guarded -as to splitting the pillars.</p> - -<p>You ought now to have the front well and firmly put -together and standing square and true as in the sketch; -only the bottom board, of which you see the front edge, is -not to be attended to at present.</p> - -<div class="figcenter" style="width: 400px;" id="fig11"> -<img src="images/figure11.jpg" width="400" height="375" alt="" /> -<p class="caption">Fig. 11.</p> -</div> - -<p>There is another way of going to work, namely, to put -the whole framework of the cage together and add the -wires afterwards. In this case (the holes having all been -made beforehand as directed here) the wires are in turn -inserted at the top, and then being slightly bent are put -in place in the bottom piece—each wire being completely<span class="pagenum"><a name="Page_23" id="Page_23">[23]</a></span> -fixed before the next is added. Either way may be tried, -but in that given above the wires are not bent at all, and -therefore have not to be straightened. Adding them, however, -afterwards is the common practice among the cage-makers. -Indeed, it generally happens in large establishments -that one set of workmen make the woodwork, and -another set add the wires—such division of labour proving -more advantageous.</p> - -<div class="figcenter" style="width: 400px;" id="fig12"> -<img src="images/figure12.jpg" width="400" height="300" alt="" /> -<p class="caption">Fig. 12.</p> -</div> - -<p>Attention is now to be given to the sides, of which Fig. -11 is a drawing. Here you need not make any corner -pillars. You have only to cut out the top and bottom -strips—the lower one, 1¾ inch wide, to match that in front: -the top, 1 inch wide, to match the straight part of the -ends of the upper front piece or gable, as you see in Fig. 12.<span class="pagenum"><a name="Page_24" id="Page_24">[24]</a></span> -You will also see by this drawing that you must nail the -side pieces <i>inside</i> the corner pillars, and <i>not upon</i> them, so -that the nails go in from the front of the cage into the ends -of the two side pieces which carry the wires. I have shown -by dots (Fig. 12) where the nail holes are, and they must -be carefully made, avoiding the places where the other -two nails come, which you hammered in when you fitted -together the front. The side strips, A B (Fig. 11), may be -8 inches long. Both sides of the cage are to be made -exactly alike. I have told you to make the lower side-rails -1¾ inch wide, because they must come to the bottom of -the pillars, for no half-inch space is required at the sides -between these rails and the bottom of the cage. It is so -left in the front, because a tray, or cleaning-board, has to -be slid in there. You had certainly better put together -the side pieces by means of the wires, as in Fig. 11, before -you nail them in their places.</p> - -<p>You now require a piece of board for the back, and -quarter-inch stuff will do very well. Bought cages are -made of much thinner wood, generally mahogany, but at -first it will be easier for you to use thicker boards. If you -round off the edges, they will not appear so thick. Very -thin deal will warp or bend after it is made up; and, indeed, -it is quite possible the back of this cage will do so. -Get the wood, however, as dry as you can, and the top -boards, when nailed on, will probably prevent it.</p> - -<p><span class="pagenum"><a name="Page_25" id="Page_25">[25]</a></span></p> - -<p>To cut out this back board, you may lay down upon the -piece from which it is to be cut the whole front of the cage, -and draw a pencil round it, only, when you come to the -bottom of the side pillars, you must draw a line straight -across from one to the other. Then cut <i>from</i> the point at -the top, as you did before. Let the grain of the wood run -up and down, <i>not across</i>, the back. Nail the back thus cut -to the side strips, as you nailed on the front, and you will -then only have the roof to put on, and the bottom.</p> - -<p>This roof may consist simply of a thin board, cut square -and true, nailed on to the two gables, and it will look much -prettier if it is made to project beyond the front. If you -measure down the slope of the front or back top-piece, you -will find it 6 inches long, and a little more. Your board -should therefore be 7 or 8 inches wide, because, although -the roof pieces meet at the top, they should come down a -little beyond the sides of the cage. As the sides are 8 -inches wide, cut the top 11 inches long, which will allow it -to project in front 3 inches.</p> - -<p>If you look at the cage at the end of these directions, -you will understand this. You must slope, or <i>bevel</i> off, the -top edges of these roof boards, to make them fit neatly -together along the ridge; and as you will paint the cage, -you can glue on a narrow strip of paper, to make it quite -water-tight. The door of these cages is generally in the -back. You merely mark and cut out a square hole about<span class="pagenum"><a name="Page_26" id="Page_26">[26]</a></span> -3 inches square. You then fit a piece in, and hinge it -either with wire, or (which is easier) by sticking on a strip -of calico down the edge of it, and fasten with a wire hook. -As the back is but a quarter of an inch thick, you will be -able to cut out the hole (before nailing on the back), with -a sharp pocket-knife; and again I say, don’t cut out the -guide-lines—cut inside them, and then neatly pare exactly -up to them. Make the bottom 13 inches long, and 10 -wide, which will allow it to project in front, and also half -an inch on each side.</p> - -<div class="figcenter" style="width: 400px;" id="fig13"> -<img src="images/figure13.jpg" width="400" height="225" alt="" /> -<p class="caption">Fig. 13.</p> -</div> - -<p>You have now to make the tray, to slide into the space -left in the front below the bottom front rail. This is to -hold sifted sand, and is made loose, because it requires to -be taken out and cleaned every day (Fig. 13). It is merely -a flat thin board (one-eighth of an inch will be quite thick -enough), with a strip nailed on, or glued on, in front, to fit -the space left for it, and other smaller strips glued on all -round it, so as to form a very shallow tray or drawer. The<span class="pagenum"><a name="Page_27" id="Page_27">[27]</a></span> -small strips can be glued on flat <i>upon</i> the top of the board, -but to fasten on the front, you must first glue on a similar -strip to those round the sides, and just such as you made -the pillars of, but not quite so thick, and then glue, or nail -on with very small brads, the front piece, nailing or gluing -it to this strip. This will make it very firm, and will -do well enough for your first cage. A, Fig. 13, shows a -part of the drawer, C is the front, and D the strip it is -glued to. The handle of this drawer or tray is to be made -of wire, unless you can find some little knob or other that -will do. If you succeed in making this cage, you will have -learned a good deal, because, although not really difficult, -it requires care and consideration; and if you are in a -hurry, you will split the wood, or make it crooked, or cut the -pieces too short. It should be neatly painted in oil-colour—<i>green</i> -is a favourite colour—but the top boards may be -red, and the wires should be left clean and bright, because -the bird often pecks at them. If you paint the <i>inside</i> of -the woodwork, it should be white.</p> - -<p>I have not here put any feeding-boxes, or seed-drawers, -because glasses are the best; but you will see two holes (Fig. -11), one inch across, in the lower side pieces, for the bird to -put its head through to get at the seed and water. A bit -of wire, forming half a hoop, supports the glasses or trays. -These ought to be cut with a centrebit—a tool you have -not, and the carpenter had better do it for you. Here is<span class="pagenum"><a name="Page_28" id="Page_28">[28]</a></span> -the cage complete (Fig. 14). You can do without making -holes in the sides, if you put two wires longer than the -rest, and bend them, as you see at B in Fig. 13, before -putting them in place.</p> - -<div class="figcenter" style="width: 400px;" id="fig14"> -<img src="images/figure14.jpg" width="400" height="300" alt="" /> -<p class="caption">Fig. 14.</p> -</div> - -<div class="figcenter" style="width: 250px;"> -<img src="images/footer2.jpg" width="250" height="125" alt="" /> -</div> - -<hr /> - -<p><span class="pagenum"><a name="Page_29" id="Page_29">[29]</a></span></p> - -<div class="figcenter" style="width: 500px;"> -<img src="images/header1.jpg" width="500" height="110" alt="" /> -</div> - -<h2 id="CHAPTER_III"><span class="smcap">Chapter III.</span></h2> - -<div> -<img class="dropcap" src="images/dropcap-t.jpg" width="100" height="120" alt="" /> -</div> - -<p class="dropcap">The previous chapters were devoted to such exceedingly -simple and easy specimens of carpentry -as can be made by any boy of eleven or twelve -years of age, or even younger, who has the -necessary perseverance, and will take sufficient care in -measuring and fitting. In both and all similar cases, it is -better for such to buy pieces of board already planed, and -of nearly the desired size; but I shall no longer presuppose -such necessity, but advance the young mechanic to the -dignity of a plane, and a few more of the more necessary -and useful tools. The list may therefore now comprise—</p> - -<div class="hanging"> - -<p><span class="smcap">1 Hand Saw</span>, 16 inches or so in length, a full-sized one being almost beyond -the powers of a boy.</p> - -<p><span class="smcap">3 Firmer Chisels</span>, quarter, half, and one inch wide.</p> - -<p><span class="smcap">1 Mallet.</span>—Chisel handles should never be struck with a hammer, which -splits the handles.</p> - -<p><span class="smcap">1 Hammer.</span>—This should be light. The best way is to buy a hammer-head, -and make the handle. A heavy one can be added, but will hardly -be required at first, and is useless for light work.</p> - -<p><span class="smcap">1 Jack Plane, 1 Smoothing Do.</span>—The jack plane is not usually added to -a boy’s tool-chest, but it is impossible to plane up a long straight<span class="pagenum"><a name="Page_30" id="Page_30">[30]</a></span> -edge without it; and as these planes can be had from 12 inches in -length, I should certainly recommend one, say 12 to 15 inches.</p> - -<p><span class="smcap">3 Gimlets, 3 Bradawls.</span>—One of each of these should be as small as can be -obtained. Add a medium and a larger one.</p> - -<p><span class="smcap">1 Screwdriver, 1 Pincers, 1 Cutting Pliers.</span>—Screwdriver should be of a -medium size; the pliers such as are used by bellhangers.</p> - -<p><span class="smcap">1 Compasses.</span>—These should be light <i>carpenter’s</i> compasses, not such as are -made of brass and steel. They are very useful.</p> - -<p><span class="smcap">2 Gouges.</span>—<i>Carpenter’s</i> gouges, not turner’s. They will answer for the present, -in many cases, to make round holes in boards. The centrebits -and braces are expensive.</p> - -<p><span class="smcap">1 Oil-stone.</span>—There is a cheap and quick-cutting stone called Nova Scotia -which will answer the purpose well.</p> - -<p><span class="smcap">Mortice-gauge.</span>—The use of this will be shown presently.</p> - -<p><span class="smcap">1 Square, 1 2-Foot Rule, Glue Pot</span>, and <span class="smcap">Brush</span>.—These are, as before stated, -indispensable. The rule need not have a brass slide; the square may -be made entirely of wood, or with a metal blade 6 to 9 inches in -length.</p></div> - -<p>The above, with the addition of a carpenter’s brace and -bit, two or three augers, about three mortice chisels, and a -hatchet, would suffice for a very large amount of good work. -Indeed, it represents almost a complete set of tools, the -only additional ones that are at all likely to be needed being -a longer (trying) plane, rebate plane, and pair of match, -or tongue and groove planes. Without any of the latter, -the young carpenter will find it easy to carry out a good -many light specimens of his ingenuity.</p> - -<p>It is much better, in general, to work with a few tools, -and contrive to make them answer all sorts of purposes, -than to lay in a larger and more expensive set at starting, -for the latter are sure to be abused and kept in bad order, -because if one chisel gets blunt, another is taken up, instead<span class="pagenum"><a name="Page_31" id="Page_31">[31]</a></span> -of sharpening the first; and planes and other tools -are treated in a similar manner, and a carelessness is engendered -fatal to success. It is astonishing how much may -be done with few and inefficient tools, but then the utmost -patience and industry have to be exercised, much as we -see prevailing among the native workmen of India and -America, who execute the most beautiful and delicate work -with tools which, in the hands of a European, would be -generally simply useless.</p> - -<p>The next work that should be attempted by the young -mechanic should be mortice and tenon jointing, as used in -constructing frames of various kinds for doors, window-sashes, -tables, and other articles of everyday use. Perhaps -one of the simplest and easiest examples will be a towel-horse, -which, at any rate, will be of use when completed.</p> - -<p>Now, it may be at once stated, that for work of this kind -especially, but generally also for all work, it is essential to -be able to square up truly the several pieces required. This -will require practice—long and careful practice—and the -beginner will meet here with his first and chief difficulty, -but he must not despair.</p> - -<div class="figcenter" style="width: 400px;" id="fig15"> -<img src="images/figure15.jpg" width="400" height="450" alt="" /> -<p class="caption">Fig. 15.</p> -</div> - -<p>It has been presupposed that a strong work-bench, table-plank -mounted upon trestles, or some sort of tolerably -efficient and firm bench has been obtained, or is accessible, -and, in addition, a strong stool upon which to saw, cut out -mortices, and so forth. A small carpenter’s bench, with a<span class="pagenum"><a name="Page_32" id="Page_32">[32]</a></span> -wooden vice, is most handy and serviceable, but is not -absolutely necessary. It will be easy to <i>make</i> one by and -by; for the present, any available substitute must be used. -The height of the proposed towel-rail may equal the length. -About 2 feet 6 inches will be a fair size, and it may be of the -simplest possible form, such as is here delineated (Fig. 15). -The upright sides may be made of strips of pine, one inch -wide and three-quarters of an inch thick—the rails 1¼ wide -and three eighths of an inch thick. The feet will be considered<span class="pagenum"><a name="Page_33" id="Page_33">[33]</a></span> -presently. If careful attention is given to the following -directions, not only will the result be certainly -satisfactory, but the way will be paved for the workmanlike -construction of a great number of similarly useful articles.</p> - -<p>The size of the rough material must always be greater -than that ultimately needed, to allow of the necessary waste -in sawing and planing. Pine boards, however, are usually -cut of certain general widths and thicknesses; and although -we have here set down stuff of <i>one inch</i> by three-quarters, -it may be cut from inch board, because very little will be -wasted by the plane, and the finished work will be sufficiently -near to the above measure for the intended purpose, -one-sixteenth of an inch or so being of no practical importance -in the construction of such an article as a towel-rail. -Get, therefore, from the carpenter, a strip of pine 1 inch -wide and 6 feet in length, cut from a board 1 inch thick, -and also a strip for the rails (of which there will be three), -4 inches wide and 2 feet 9 inches long, cut from a half-inch -board. The rails you are to saw yourself from the latter -strip, which will give you practice in sawing a straight -course, and the <i>work</i> is easy in half-inch stuff. You may -therefore begin by cutting these, for which purpose you -will want guide-lines dividing the strip into three of equal -width. There is a very simple way of marking these by -means of a chalk line, which I will here describe.</p> - -<p>The width of the board I set down at 4 inches, because<span class="pagenum"><a name="Page_34" id="Page_34">[34]</a></span> -the rails, when finished, will be 1¼ inches each, or, in all, -3¾ inches. As each contains eight eighths, as already -explained, 4 inches will contain thirty-two eighths. Dividing -by 3, we shall have ten eighths for each strip, or 1¼ -inches, and two eighths, or a quarter of an inch, to spare -for waste. Take the compasses, therefore, and open them -to 1¼ and a little over (rather less than to the next division -on the rule), and take it off at each end of the board -(Fig 16, A B).</p> - -<div class="figcenter" style="width: 400px;" id="fig16"> -<img src="images/figure16.jpg" width="400" height="150" alt="" /> -<p class="caption">Fig. 16.</p> -</div> - -<p>Take off, again, from this to mark the width of the next -strip, and the board will be divided with sufficient accuracy -for our present purpose. Take a piece of twine, long -enough to stretch from end to end of the plank, and something -over, and tie a knot at one end. Stick a bradawl -through the string, close to this knot and into the board, -as seen at C of the same figure. Take a lump of chalk, -and chalk the line from end to end. Then strain it down -the board, holding it by the left hand, so that it is stretched<span class="pagenum"><a name="Page_35" id="Page_35">[35]</a></span> -from one mark to the other, where the saw-cut is to be -made. With the finger and thumb of the other hand, raise -it a little in the middle, and let it suddenly go, when it -will make a perfectly clear and straight line upon the -board. Make a similar and parallel line for the next saw-cut. -In the present case, you need not mind cutting this -chalk mark out. Try and saw right down, so as to split it.</p> - -<div class="figcenter" style="width: 400px;" id="fig17"> -<img src="images/figure17.jpg" width="400" height="300" alt="" /> -<p class="caption">Fig. 17.</p> -</div> - -<p>You now have your strips cut out, but they require to be -planed. You might, indeed, with advantage, have planed -the whole strip on both sides before marking and cutting -it, but it is equally easy to do it afterwards. The jack -plane is the one to be used for this purpose. I must suppose -it to be sharp and in good order; if not, ask some -carpenter to set it for you for the present, but I will soon -tell you how to do it for yourself. Indeed, you will have<span class="pagenum"><a name="Page_36" id="Page_36">[36]</a></span> -to learn how to sharpen all your tools before you can be -called a good workman. If the plane is properly set, the -cutting edge will project very slightly only from the -bottom; so that when held as in Fig. 17, and the eye -directed along the sole, only a narrow shining slip of -metal will appear. If too far out, it will hitch and make -bad work; if not far enough, it will not cut at all; but -the common fault of beginners is to have it too far out, -because from their imperfect handling of this tool they -often fail to make it cut, when in the hands of a carpenter -it would work well. Now, if the iron projects too far, hold -it as shown, so that you look along the sole, and give it a -tap with your wooden mallet on the upper face at A, and -this is also the way to loosen the wedge and irons for -removal. By a blow at B, you can send the cutting edge -forward to cut more deeply, or in this case you may tap -the iron itself with a metal hammer, but tapping the end -of the wood is better.</p> - -<p>To plane the edges of these strips, you ought to have a -bench with a vice, but there are ways and means to do -without it, and one is so good that I shall speak of it here, -although it necessitates a somewhat abrupt break-off in my -description of the towel-rail. It is a kind of vice that is -fixed to a board which is laid upon the work-bench when -required.</p> - -<div class="figcenter" style="width: 400px;" id="fig18"> -<img src="images/figure18.jpg" width="400" height="325" alt="" /> -<p class="caption">Fig. 18.</p> -</div> - -<p>In Fig. 18 is a drawing of one of two kinds of such vices<span class="pagenum"><a name="Page_37" id="Page_37">[37]</a></span> -which I will explain. This first consists of two pieces of -wood (ash will be better than pine) about 9 inches long -and 2 inches thick. They are cut in the shape given in -the drawing, and screwed to the board, not tightly, but so -as to move freely upon the screws. The board should be -an inch thick to give the screws a firm hold. You can see -by the figure that the tails of the pieces cross each other -sometimes when in use. To allow of this, they are cut like -B and C, so that one can go inside the other. Now, if you -consider a little, you will understand that if we stand a -strip of board between the two, and push it forward against -the insides of the tails of these curiously-shaped blocks, it -will make the opposite knobbed ends close nearer together, -and these will grip the piece of wood, and the harder we<span class="pagenum"><a name="Page_38" id="Page_38">[38]</a></span> -push it forward, the more closely it will be gripped and -held; but the moment we draw back the piece, the two -jaws will open to let it go free. You can try first of all -upon a thin piece, which can be shaped by your knife, and -make a model of this vice, and then if you can’t manage to -cut out such a one of thick wood, the carpenter would do it -for you, and it will be handy for many purposes. If you -have nothing of this kind, nor a vice to your bench, drive -in two pins or pegs of wood, or two nails, a little way apart, -so as to allow your strip of wood to stand upon edge between -them, and drive two more a little way from these; -then one at the end to form a planing stop. A tap at the -sides of these nails will cause them to hold the strip edgewise, -quite well enough to allow you to plane it. There<span class="pagenum"><a name="Page_39" id="Page_39">[39]</a></span> -are other ways, and I shall describe them by and by. In -the meantime use nails, or any other plan that will answer.</p> - -<div class="figcenter" style="width: 400px;" id="fig19"> -<img src="images/figure19.jpg" width="400" height="250" alt="" /> -<p class="caption">Fig. 19.</p> -</div> - -<div class="figcenter" style="width: 400px;" id="fig20"> -<img src="images/figure20.jpg" width="400" height="140" alt="" /> -<p class="caption">Fig. 20.</p> -</div> - -<p>I shall suppose, therefore, that one of the narrow strips -is thus set on edge upon your bench ready to be planed. -Grasp the handle of your plane firmly with the right hand, -and lay hold of it in front of the iron with the left. Draw -it back, and then send it steadily forward, pressing it -downwards at the same time. Now the advantage of a -long plane is, that it does not descend into the hollows of -the work, but rests upon the projections, as in Fig. 19, A. -A short plane would do as seen at B, and therefore would -never make a long straight edge. You have two special -points here to attend to. You have to plane a level line -from end to end, and also keep the edges square to the -sides, which is by no means easy at first. You must keep -trying it with your square, as I have shown you in Fig. 20, -and not rest satisfied until the handle fits close to the side -of the strip, and the edge lies also close upon that of the -strip anywhere along its length. I daresay you will think -this of no importance in such a common thing as a pine<span class="pagenum"><a name="Page_40" id="Page_40">[40]</a></span> -towel-horse; but I may tell you this is the very secret of -carpenter’s work, and when you can saw and plane truly, -and work “to square,” you can make almost anything. It -is true that the strips for the rails are not of great importance -in this case, but the upright side pieces are, and if -these are out of truth, the holes cut through them for the -rails, which are called mortices, will be out of truth also, -and you will see the towel-horse, when it is made, all -twisted and awry, and nothing you can do will make it -stand firm or look well. It is, in short, no use to pretend -to learn carpentry unless you at once make up your mind -to succeed, and therefore you must always use the square -and try your work as you go on. All the difference between -the usual work of carpenters, and that of boys or men who -do not know how to work, consists of the squareness and -good fit of what the former make. Boys never seem to -trouble themselves about such things, and so you see their -boxes and rabbit-hutches look twisted, and being badly -fitted, they soon go to pieces.</p> - -<p>Having planed up the sides and edges of the rails as -square and true as you can, cut the other long strip in half, -and square up this also, taking care that both pieces are -alike and both truly worked. If your bench is sufficiently -long to take the whole strip, plane it up before you cut it -across, and you will be sure to have the sides of your towel-rail -equal in size. You have now to make your first essay<span class="pagenum"><a name="Page_41" id="Page_41">[41]</a></span> -in cutting mortices. Follow these directions, and you will -not fail. I shall not limit the description to these special -mortices, but give you general directions.</p> - -<div class="figcenter" style="width: 400px;" id="fig21"> -<img src="images/figure21.jpg" width="400" height="175" alt="" /> -<p class="caption">Fig. 21.</p> -</div> - -<p>Fig. 21 represents a bar of wood—the side of the towel-horse, -for instance—with a mortice cut through it at A, -and others marked out at <i>ab</i>, <i>cd</i>. Below, at B, is a gauge, -of which the construction and use will be explained presently. -F shows how the feet are to be attached and cut. -They are morticed while in a “squared-up” condition, and -shaped afterwards according to fancy; sometimes they are -left square, and knobs screwed below to make two feet.</p> - -<p>These mortices may, of course, be of any desired length -or width. Those required for the towel-rail sides will be -1¼ inch long by half an inch wide <i>nearly</i>. The planing of -the strips may have reduced them more or less below the -exact size specified, try therefore with the compasses what -the precise thickness is of the ends, and measure that<span class="pagenum"><a name="Page_42" id="Page_42">[42]</a></span> -thickness on your two-foot rule. You now want to draw -the lines <i>a t</i>, which I have represented as extending the -whole length of the strip, and as all the mortices are to be -alike, you may so mark them. The gauge B is of two -parts, a sliding piece, C, and a rectangular bar of wood -about 9 inches long and half an inch square. This slides -stiffly through the mortice in C, and is fixed at any part -by the small wedge D. This gauge you can easily make. -It is <i>not</i> a mortice gauge properly so called, because the -latter has two marking points instead of the one seen at <i>h</i>, -and which may be the point of a brad driven in and filed -up to an edge. Loosen the wedge slightly, and draw back -the rectangular bar, or push it forward, until you think that -the space between the sliding piece and the point is about -that which is required on each side of the mortices, so that -if you set the wedge firm, and resting the sliding piece -against the edge of the board, cause the point to make a -mark, and repeat this on the other side of the same face of -the wood, there will be left between the marks thus made -the exact width of the required mortice. Try it, and if not, -give a tap to the instrument, and adjust it until the space -is exactly correct. Then fix all firm, and holding it so that -the little point will mark the wood, while the head or sliding -piece is against the side of the board, run the tool from -end to end, or run it along just where the mortices are -required, using both hands. You will thus make the two<span class="pagenum"><a name="Page_43" id="Page_43">[43]</a></span> -long lines between which the mortices have to be cut. Now -turn the wood over, and do the same on the other side. -You are now quite sure that these lines, on opposite sides -of the piece, agree exactly in position, which is the object -of using a gauge; and as you have planed up a second strip -to exactly the size of this first, you have but to repeat the -process (no measuring being necessary) upon that; and -you may be satisfied that thus far the two sides of the -towel-rail will tally. You now set off with the compasses -upon one of these lines the <i>lengths</i> of the mortices in their -proper places, and at the points thus marked, using your -square for the purpose, mark the end lines of these mortices; -but when so doing, carry the lines across, as <i>a b</i>, <i>c d</i>, -and down the sides and across the opposite side. With the -square this will be easily done, the blade of it being laid -<i>flat</i>, so that its edge becomes the ruler, while the handle -becomes the guide or gauge resting against the side of -the wood. At E, Fig. 21, this position of the square is -shown.</p> - -<p>By thus carrying round all the lines, you will have the -mortices marked on both sides in exactly the same relative -position, so that you can (and must) cut them half from -one side and half from the other, using the chisel nearest -to the size required, but <i>always of less width</i> (or length) -than the mortice, because <i>you must never cut out the guide -lines</i>, but must keep within them, only carefully paring<span class="pagenum"><a name="Page_44" id="Page_44">[44]</a></span> -the wood at last close to them. You will never cut mortices -correctly, unless you thus mark the position on both -sides, and work as directed.</p> - -<p>The ends of the cross rails will not have to be cut into -tenons, as they will fit as they are, only requiring to be -glued into their places, when, if you have worked carefully, -the whole will look well, and will be square and true, -without twist; but if you did not plane up the sides square, -you will find the towel-rail awry and unworkmanlike. -Although, however, there is no necessity to make regular -tenons in the present case, the usual way is to do so, and -to fix with wedges, as in Fig. 15. After a mortice has -been cut straight through a piece as directed, this mortice -is slightly eased, or sloped off, as seen at <i>a b</i>, which is a -section of one. The rail or tenon <i>c</i> is put through after -being brushed with glue; and when in exact position, two -wedges are glued and driven in at each end, as seen in -the drawing. After all is dry, these wedges being firmly -united to the rail, as seen at <i>k</i>, prevent it from being -drawn back or moved. Nearly all mortice and tenon joints -are fixed in this way.</p> - -<p>As I am describing this kind of work, I may as well -explain the method of marking and cutting tenons, as it -will answer not only for affixing the feet, as shown in Fig. -21, but for all similar work.</p> - -<div class="figcenter" style="width: 400px;" id="fig22"> -<img src="images/figure22.jpg" width="400" height="250" alt="" /> -<p class="caption">Fig. 22.</p> -</div> - -<p>In Fig. 22, I have illustrated the mode of marking out<span class="pagenum"><a name="Page_45" id="Page_45">[45]</a></span> -tenons, and at D is a double tenon, which is in wide pieces -often substituted for the single, and makes an excellent -joint. The longitudinal lines <i>e</i>, <i>f</i>, <i>g</i>, <i>h</i>, are marked as -before with the gauge, whether for single or double tenons; -the line <i>a b</i>, with the assistance of the square; the cheeks, -<i>c</i> and <i>d</i>, are then cut off entirely with a fine saw, called on -this account a tenon-saw,—and care must be taken as before -not to cut out the guide lines. If, instead of the outer -cheeks, the piece between them is to be removed to make a -double tenon, this must be done with mallet and chisel, -after carefully sawing down the lines <i>x y</i>; and the chisel is -to be used first on one side and then on the other, by which -means the shoulder will be cut true to the guide lines. If, -however, the cut across should curve a little downwards -like <i>n</i>, it will not much matter, so long as the <i>edges</i> fit -closely. It is nevertheless better to cut straight across.<span class="pagenum"><a name="Page_46" id="Page_46">[46]</a></span> -The outer cheeks of this will be marked and cut as in the -single mortice (Fig. 22).</p> - -<p>If a workman has to cut many mortices on pieces of the -same size, he frequently constructs a rough mortice gauge -with double points, which marks both sides of the mortice -at once, like K. A fixed block at K, the right distance -from the points, <i>l m</i>, of two nails, is sufficient when all the -mortices are to be alike. There is, however, a regular -double-pointed gauge, made generally of ebony, plated -with brass, and a brass rule to which one of the points is -fixed, and which is acted on by a screw at the end, which -can be turned by the thumb and finger. This has the effect -of separating or closing the two points according to the -desired width of the mortice, its distance from the side of -the piece being regulated as before by the sliding head fixed -by a wedge. This is an expensive tool, and need not be -purchased. There are also, let me add, many costly tools -of various forms and uses; but let the boy’s motto (and -man’s, too, for all that) be, “<i>Do as well as you can without</i>.” -You have no idea how a little ingenuity and contrivance -will save your pockets, and that, too, without in -the least tending to spoil your work. All you require are -a few of the most generally useful tools in first-rate condition—chisels, -saws, and planes, sharp and well set, and fit -for work at any moment.</p> - -<p>With regard to uniting two pieces of wood or other<span class="pagenum"><a name="Page_47" id="Page_47">[47]</a></span> -material with glue, it must be remembered that if you use -this substance in a thick semifluid state, and in quantity, -its effect will be lost. Make it a rule to put on as thin a -coat as possible, and let it be not thicker than cream, so -that it will freely flow into corners, and spread evenly over -the surfaces to be united. Make the wood also <i>quite warm</i>, -so that the glue shall not be suddenly chilled, and let it be -used boiling. Always heat it either in a proper glue-pot, -or at any rate, place the vessel which contains it (a small -gallipot, for instance) inside another vessel in which water -can be kept boiling.</p> - -<p>The glue, which should be thin and transparent, being -broken into small pieces, should be put into such a vessel -as suggested, and covered with cold water, and it should -be allowed to remain thus until swollen and softened. -Then bring the water in the outer vessel to the boiling -point, and do not use the glue until it is entirely dissolved -and of one uniform consistence. It should be stirred while -boiling with a piece of stick, and a brush used to lay it -upon the pieces to be joined. It very generally happens -that pieces glued by boys fall apart almost directly. This -is almost entirely due to the fact that the glue is used thick -and clotty, and in too great quantity, while the wood is -never made warm as it should be. If two pieces are properly -joined in this way, it is almost impossible to separate -them at the joint—the wood itself will give way and split<span class="pagenum"><a name="Page_48" id="Page_48">[48]</a></span> -before the glue will yield to the strain. Carpenters use -various forms of clamps or vices to hold work together -until the glue shall be dry; but for boys by far the best -plan, where any such holdfast is needed, is to bind the -parts together with twine, and then to set them aside for -twelve hours at least. It is seldom that articles once -united by glue and separated will unite firmly a second -time.</p> - -<div class="figcenter" style="width: 250px;"> -<img src="images/footer3.jpg" width="250" height="125" alt="" /> -</div> - -<hr /> - -<p><span class="pagenum"><a name="Page_49" id="Page_49">[49]</a></span></p> - -<div class="figcenter" style="width: 500px;"> -<img src="images/header2.jpg" width="500" height="110" alt="" /> -</div> - -<h2 id="CHAPTER_IV"><span class="smcap">Chapter IV.</span></h2> - -<div> -<img class="dropcap" src="images/dropcap-t.jpg" width="100" height="120" alt="" /> -</div> - -<p class="dropcap">The exercise of a boy’s mechanical tastes upon -works of practical utility is, of course, far preferable -to its expenditure upon mere trifles, made -one day to be cast aside and destroyed the next; -and as there is scarcely any household that does not need -its furniture repaired or added to from time to time, I shall -now give directions for the construction of one or two -articles that seem to be within fair scope of a young -mechanic’s abilities. The first is a plain, useful table, without -a drawer, and with square legs, because without a lathe -the latter cannot be made ornamental; and lathe work -will occupy some future pages, since it is necessary first to -give the young mechanic a fair insight into the principles -and practice of plain carpentry and joinery.</p> - -<p>The <i>very</i> young mechanic, so far as my experience of -him goes (and it is rather extensive), makes his early -attempt by sticking the points of four nails into the corners -of any tolerably square piece of board he can lay hands<span class="pagenum"><a name="Page_50" id="Page_50">[50]</a></span> -on. His next attempt, when he has risen to the dignity -of a knife and gimlet, is to place four <i>wooden</i> legs at the -corners of a similar board, which, if the said legs are <i>glued</i> -in (by which a wonderful mess is always made of the -structure), is considered a great feat, and worthy of the -admiring patronage of fond parents and playmates. Now, -a table does not consist of any such arrangement of pieces, -although I certainly have seen sometimes, in the cottages -of the poor, a three-legged affair of this nature, which is -just nothing more than a magnified milking-stool. We -cannot content ourselves now with anything of the kind. -We shall have to work away with plane and chisel and -square, and with neat tenon and mortice joints first construct -the frame upon which the top will be placed, and -then finish it <i>secundum artem</i>, the English of which, as I -am writing to boys, I shall not reveal.</p> - -<p>The table shall be 3 feet long, 1 foot 8 inches wide, 2 -feet 4 inches high; the top board being half an inch thick -when planed and fitted, for which it will therefore be required -to be three-quarters of an inch in the rough. The -legs demand attention first. Plane up strips cut from a -2-inch board, and let them be exactly 2 inches wide. These -must be worked up with the greatest possible accuracy, or -it will be impossible to fit the framework so as to make the -table stand truly or bear inspection. After four such strips -have been planed up, cut a piece from a half-inch board, or<span class="pagenum"><a name="Page_51" id="Page_51">[51]</a></span> -from a board that will plane to half an inch. Let this be -4 inches wide and 9 feet long, and be sure to plane this -also truly, and to make the edges square to the sides.</p> - -<div class="figcenter" style="width: 325px;" id="fig23"> -<img src="images/figure23.jpg" width="325" height="400" alt="" /> -<p class="caption">Fig. 23.</p> -</div> - -<p>If you have no strip that will answer of 9 feet long, you -can cut two or more instead, remembering that you will -require two pieces each 18 inches long and two of 2 feet 9 -at the least, all as nearly alike in <i>width</i> as possible. You -have now all that you will need for the framework of your -table—the top may be left till the rest is fitted. Now you -may proceed to cut the requisite mortices in the legs, which -you will understand by sketch Fig. 23, which represents -one corner of the table before the top is added. There is<span class="pagenum"><a name="Page_52" id="Page_52">[52]</a></span> -no more difficulty in this than in the previous work, except -perhaps that somewhat more care is requisite in squaring -up the several pieces and cutting the mortices with accuracy. -Use the gauge as before in marking the mortices, trying it -until it is so fixed that it will leave the proper width of the -holes, namely, half an inch (which is the thickness of the -strips which are to form the framework). This is upon -the supposition that your gauge has but one marking -point: but to explain its use.</p> - -<div class="figcenter" style="width: 400px;" id="fig24"> -<img src="images/figure24.jpg" width="400" height="125" alt="" /> -<p class="caption">Fig. 24.</p> -</div> - -<p>I shall now introduce to your notice a regular mortice-gauge -of two points, which is vastly more convenient. -This is represented in Fig. 24. The main stem is grooved -along its length on one side with a dovetailed slit, that is, a -groove which is wider below than above. This is generally -made in a brass plate attached to the stem of the gauge, -but sometimes in the wood itself. In this slides a slip of -brass which can be drawn back by pulling the knob A, or -by turning a thumbscrew at one end, as in the more expensive -gauges. One of the marking points is fixed in the end -of this slide, the other in the wood (or metal) beyond it, at<span class="pagenum"><a name="Page_53" id="Page_53">[53]</a></span> -B, and when these are allowed to be together they form -but one point, being flattened on one side, so that they will -fit accurately against each other. Thus it is easy to separate -the two points at pleasure to the exact width of the required -mortice. By means of the wedged sliding piece C, we now -have merely to determine how far the edge of the mortice -is to be from <i>one side of the piece</i>. Thus, suppose that in -the present case we should prefer to have the side of the -frame nearer to the outside edge of the legs than to the -inside, we can so arrange it easily; but we must then take -care to gauge all alike, either from the inside edge or the -outside. We do not, therefore, with this kind of gauge -work from <i>both</i> edges, and leave the space <i>between</i> the lines -for the width of the mortice, but we work from <i>one</i> edge -only of the piece of wood, and mark the mortice at once in -any desired position. I need hardly repeat, that for any -particular job, a very good substitute for such gauge can -be made by driving two small nails into a strip of wood cut -with a projecting piece to serve instead of the movable -head.</p> - -<div class="figcenter" style="width: 400px;" id="fig25"> -<img src="images/figure25.jpg" width="400" height="500" alt="" /> -<p class="caption">Fig. 25.</p> -</div> - -<p>Let us now proceed with the work in hand. One of the -legs of the table, before being worked into shape, is shown -in Fig. 25; the dotted lines show how it will be eventually -sloped off below the mortices which carry the top frame. -These mortices must not now go through the legs, and -therefore you will have to be very careful to hold the chisel<span class="pagenum"><a name="Page_54" id="Page_54">[54]</a></span> -upright, so as to insure the <i>squareness</i> of the frame when -put together. The mortices being in adjacent sides, will of -course meet, but it will be advantageous to cut those which -are intended to receive the two longest strips, viz., the -front and back, rather deeper than the other two. First -set off an inch from the top of the leg at the line A B. If -less than this intervenes between the top of the mortice -and the end of the leg, you will probably break the piece -out and spoil your work. As the side boards are 4 inches<span class="pagenum"><a name="Page_55" id="Page_55">[55]</a></span> -wide, and must come flush with the top of the legs, you -will have to cut them like C, and there will be 3 inches left -for the tenon, all of which may be left, as the wider this is -the more hold it will have on the legs into which it is to be -glued. It is plain, therefore, that the mortice will be 3 -inches long and half an inch wide; and when you have -marked it to this size, take care to cut it accurately, because -if it is too small, you will break out the piece between -the mortices when you try to force in the frame pieces, and -if too large, you will scarcely get the whole to remain secure. -Work therefore exactly to gauge. It is usual to keep these -side and end pieces more to the outside of the legs than the -inside, as F, where you are supposed to be looking at the -<i>inside</i> corner; and if you look at D (which shows the top or -cross section of a leg, as if after the pieces were fitted you -had sawn off the leg close down to the mortices, exposing -them to view), you will see that by thus keeping near the -outside edges you get <i>both</i> mortices deeper than if you cut -them, like E, in the middle of the sides of the leg. Of -course, the deeper these tenons are let into the legs, the -stronger their hold will be. There will now only remain to -warm all the pieces and glue them into their respective -places, with the precautions before stated as to the thinness -of the glue and speed of the operation. See that all -stands square and true; if not, a tap here and there as -required will set it straight, and then let all stand till dry.</p> - -<p><span class="pagenum"><a name="Page_56" id="Page_56">[56]</a></span></p> - -<p>I have told you to cut the side and end pieces 18 inches -and 2 feet 9 respectively, so that if the mortices are 1½ -inches or so deep, your frame will be about 1 foot 6 inches -wide, and 2 feet 6 inches long. The top, which is to overlap -as usual, will be now prepared as follows. It will not -be possible to make this of a single width of board; and -nothing will more fully test the young workman’s skill, -than planing the edges of two pieces so that they shall fit -accurately together. It must, nevertheless, be attempted.</p> - -<p>Cut two pieces of three-quarter-inch board, and plane -the sides as accurately as possible. Then set them up -edgewise, either singly or together, and plane the edges -with steady, long strokes of the longest plane you have, -set fine—that is, with the cutting edge projecting but -slightly. Try each singly with the square from end to -end, and then lay them on any perfectly flat surface, as on -your bench, or on a table, and see whether the edges lie -close all along. Remember, too, that they may do so -when one surface is upwards, and not when turned over, as -will occur when the edges are not square to the sides. In -cutting out the pieces, therefore,—which, when finished, -are to be together 1 foot 8 inches,—you should make them -1 foot 9, so as to allow you a whole inch to waste in planing -and fitting. When both are as true as you can get -them, lay them down near together, and brush the edges -with boiling hot glue. Then immediately put them together,<span class="pagenum"><a name="Page_57" id="Page_57">[57]</a></span> -and rub them a few seconds one against the other, -till they seem to stick slightly. Then leave them in their -exact position, and drive a couple of nails into the bench -against the outside edges, so as to keep them together, or -in any other way wedge them tightly in position until they -are quite dry. When the glue is hard which has been -squeezed out along the joint, you may run a plane all over -the united boards, and you ought hardly to see the joint, -which will be nearly as strong as any other part.</p> - -<p>This top has now to be attached to the frame, as follows. -Cut some pieces like K in Fig. 25, and glue them here and -there along the inside edges of the frame, so that one side -of them shall come quite flush with the upper edge. To -these the top has to be glued. Lay it, therefore, with its -under side upwards, upon the floor (I suppose the short -pieces glued and <i>dry</i> on the frame), and having also glued -the sides of the short pieces which will touch the under -side of the table top, turn the whole upside down, with its -legs in the air, adjusting it quickly. Its own weight will -keep it in position until dry; or, if not, it is easy to lay an -odd board or two across, and put some weights upon them. -When dry, turn over your table, and plane round the edges -where necessary; and, if it does not stand very well, trim -the bottoms of the legs. Clean off glue, and rub any rough -places with sandpaper or glasscloth, filling up any accidental -holes with putty, after which it will be fit for receiving<span class="pagenum"><a name="Page_58" id="Page_58">[58]</a></span> -paint or stain, if it is not considered desirable to leave -it white. The corners and edges of the top may be rounded -off, to give a finished appearance.</p> - -<p>I showed by dotted lines the usual shape of the squared -legs. They are planed off, tapering from below the frame, -and this should be done after the mortices are cut, and -before fitting the parts together. The best way to insure -equal taper of all the legs, is to prick off at the bottom of -each equal widths from the corners or edges, and to run a -pencil line from the point where the taper is to begin to -these marks. Then plane exactly to the lines thus made.</p> - -<div class="figcenter" style="width: 400px;" id="fig26"> -<img src="images/figure26.jpg" width="400" height="350" alt="" /> -<p class="caption">Fig. 26.</p> -</div> - -<p>Let us now consider what errors of construction are most -likely to occur in working out these directions. First, it -is possible that the framework may be out of square. This -may proceed from two causes. In the first place, the side -or end pieces may not be of equal length between the legs, -owing to some one or two being driven further into their -mortices than the others. To avoid this, which is not uncommon -in many works of a similar nature, it is well -always to mark the length that each is to be, irrespective -of the part within the mortices, as Fig. 26, A and B. -If the space on each between the dotted lines (<i>carefully -marked by means of a square</i>) is equal, it is no matter -whether C and D are also equal. We have only to take -care to let them into the mortices to a greater or less depth, -until the line comes exactly even with the inside edge of<span class="pagenum"><a name="Page_59" id="Page_59">[59]</a></span> -the legs. Again, it is possible that when the table is -placed upon its legs, these may not rest truly on the floor. -Probably one or two of the frame pieces run up like E, -instead of standing at right angles to the legs. This results -from the mortice not being cut correctly; and as you -cannot, in this case, mark both sides and cut from both, -as you did in making the towel-horse, this is not unlikely -to happen. It will not, therefore, signify much if you -purposely cut your mortices a little too <i>long</i>, and then, -when you have placed the table on its legs, after gluing -up the frame, and before it is dry, you can force it to stand<span class="pagenum"><a name="Page_60" id="Page_60">[60]</a></span> -truly, and then wedge up with glued wedges where necessary. -You cannot, however, do this with the <i>sides</i> of your -mortices, because you require these to fit exactly; you -must therefore use extra care in keeping these as true as -possible. In many cases you can wedge the <i>ends</i> of tenons -to correct a bad fit, but never the sides. These are the -probable, or I will say <i>possible</i>, faults against which to be -on your guard.</p> - -<div class="figcenter" style="width: 500px;" id="fig27"> -<img src="images/figure27.jpg" width="500" height="300" alt="" /> -<p class="caption">Fig. 27.</p> -</div> - -<p>In making a similar table with a drawer, the same operations -have to be gone through, but the upper frame is somewhat -differently constructed, and the corners of the drawer -are united with dovetails. Plane up the legs as before,<span class="pagenum"><a name="Page_61" id="Page_61">[61]</a></span> -but cut mortices as at A. Fig. 27, which represents the -right-hand hinder leg as you would see it standing in front -of the table, and before the framework had been fitted in -its place. B is the other hind leg, with the tenoned strips -just ready to be driven in. The piece E is made as before, -as is also C and its opposite piece at the <i>ends</i> of the table. -But this pair of mortices, you see, are made shorter than -before, and the strip C is notched at the bottom as well as -at the top, forming a regular <i>tenon</i>, as it is called. Below -this first is a second mortice, cut the other way, the longest -side standing <i>across</i> the leg to receive a strip, D, upon -which afterwards another strip, X, will be nailed or glued, -forming the rebate in which the drawer will slide, and of -which the upper surface must be level with that of the strip -M. There is a plane for cutting out rebates without the -necessity of adding a strip, but I do not suppose you as -yet to have such a one. When these pieces, C and D, are -driven up close into their places, they will touch along -their sides, so that on the outside they will appear as one -piece. Of course there will be a similar pair on the right-hand -side of the table. D ought to be tenoned, so that the -side on which X is to be nailed will lie flush or level with -the corner of the leg, so that the strip X shall project -wholly beyond it.</p> - -<p>The left-hand <i>front</i> leg is shown at P, with its mortices, -and the tenoned strips between which the front of the<span class="pagenum"><a name="Page_62" id="Page_62">[62]</a></span> -drawer will lie, closely fitting when shut. These front -strips should be each 2 inches wide, the mortices 1 inch -long, or as long as you can safely cut them; you must -tenon the cross pieces, of course, to fit these.</p> - -<p>All the rails may be of half-inch board. Mark all tenons -across with the square as before, so as to give the exact -<i>inside</i> dimensions, and you cannot well go wrong. These -lines, too, will guide you in keeping the framework square -and true; for if you have planed the legs correctly, and -your strips are inserted exactly to the aforesaid lines, it -stands to reason the work will be satisfactory. To make -the drawer, observe, first, that it is not like a box as most -boys would make it, for when turned upside down, as in -Fig. 28, Fig. B, you will find the sides projecting beyond -the bottom, which projections rest in the rebate, X, of the -last figure, and take the whole weight of the drawer, enabling -it to slide easily and smoothly in and out, especially -if those surfaces which are in contact are rubbed with soap -or blacklead, or a mixture of the two. At C you have a -drawing of the same, with the bottom removed. This, you -see, is a square or oblong frame dovetailed together, and -when it is glued and dry, the bottom is slid in along the -grooves in the sides (one of which is seen at <i>x x</i>), and a -couple of brads driven through it into the back rail, K, -fixes it completely. The front board of the drawer is cut -and planed to fit exactly between the two rails which were<span class="pagenum"><a name="Page_63" id="Page_63">[63]</a></span> -morticed into the legs, as shown in the last fig., and is -always of thicker stuff than the sides or bottom. It may, -in the present case, be half-inch, and the rest quarter-inch.</p> - -<div class="figcenter" style="width: 500px;" id="fig28"> -<img src="images/figure28.jpg" width="500" height="400" alt="" /> -<p class="caption">Fig. 28.</p> -</div> - -<p>If you look at C, you will observe that the front and -sides of the drawer are of the same depth, and that only -the back is narrower. (Remember that in this cut the -drawer is seen from below, the groove <i>x x</i> being near the -bottom of the sides, and level with the bottom of the back.)</p> - -<p>To cut dovetails is not difficult, but requires neatness -and care—a fine saw (dovetail or light tenon-saw) and a -really sharp chisel; and, above all things, remember not<span class="pagenum"><a name="Page_64" id="Page_64">[64]</a></span> -to cut out the lines which have been drawn as guides. H is -the <i>end</i> of the front of the drawer; L the left side. Having -cut out the latter, and planed it up nicely, draw a line, by the -aid of the square, one quarter or three eighths of an inch -from the end <i>across</i> it. This will be the line <i>o p</i> of the bottom -of the dovetails. Then mark and cut out two or three, as -seen in the drawing, using the saw where you are able, and -clearing out with the chisel in other places. From <i>o p</i>, -measure the exact <i>inside</i> width of your drawer, and beyond -the second line made across at that distance, leave a quarter -of an inch for the second dovetails, and cut them out as -you did the first. Now, prepare a second precisely similar -piece for the opposite side. Next lay L in place upon H -very truly, and with a fine-pointed hard pencil, or a scriber -(a sharp-pointed steel marker), trace round the dovetails, -marking them on the end of H, and with a sharp chisel -cut them in a quarter of an inch deep, which will allow -them to take the side piece exactly flush and level. Mark -these two which have been so fitted, and proceed to do the -same at the other end of the front piece, tracing these, as -before, from the dovetails of the opposite side, which are to -be there inserted. You do exactly the same with the back -piece; but as this is both narrower and thinner, the dovetails -will be cut quite through it, and will be seen on both -pieces after being glued up, and there will only be room -for one dovetail, instead of two. When all are cut, lay the<span class="pagenum"><a name="Page_65" id="Page_65">[65]</a></span> -pieces in position, glue quickly, press all together, and -contrive to wedge up or bind round the whole until dry, -testing with the square and adjusting, as maybe necessary. -We shall return to dovetailing again, but these not requiring -<i>excessive</i> neatness, will be a good beginning, and show -you in what special points care is needed in such work. -Nothing remains but to plane a piece for the bottom, and -slide it into place.</p> - -<div class="figcenter" style="width: 150px;"> -<img src="images/footer1.jpg" width="150" height="125" alt="" /> -</div> - -<hr /> - -<p><span class="pagenum"><a name="Page_66" id="Page_66">[66]</a></span></p> - -<div class="figcenter" style="width: 500px;"> -<img src="images/header5.jpg" width="500" height="110" alt="" /> -</div> - -<h2 id="CHAPTER_V"><span class="smcap">Chapter V.</span></h2> - -<div> -<img class="dropcap" src="images/dropcap-i.jpg" width="100" height="120" alt="" /> -</div> - -<p class="dropcap">In the last chapter we entered a little upon the -matter of dovetails, but as the mode of uniting -the angles of boxes, drawers, and such like, is -of almost universal application, it will be as well -to devote a separate short chapter to the subject.</p> - -<p>There are several different kinds of dovetails used, according -as it may be desired to let them appear upon the finished -work, or wholly or in part to conceal them. Carpenters -generally use the kind which is visible on both sides, -cabinetmakers, as a rule, take special pains to conceal it, -only using the other form upon work that is to be afterwards -covered with veneer (a thin covering of some -ornamental and more expensive wood glued upon the -surface of that which is of less value, and of which the -article is made).</p> - -<p>The dovetail described in the last chapter, as proper for -the attachment of the sides to the front of a drawer, is not -that which is ordinarily used by the carpenters, but the<span class="pagenum"><a name="Page_67" id="Page_67">[67]</a></span> -following, which is somewhat more easy to make, and is -the same as would be used for the other corners of such -a common drawer as that described.</p> - -<p>I must at the outset remind my young readers once again -of the standard rule, without due attention to which they -have <i>no hope of success</i> in this neat and delicate operation -of carpentry. <i>Never cut out your guide lines, but leave them -upon your work</i>, and use your square diligently upon the -<i>edges</i> of your work, the bottom of the dovetails, sides of the -same, and upon the sides of the pins. Never mind the -<i>time</i> necessary for this. You are doing work, remember, -that is to bear inspection,—work that will stand wear, and -be really useful in the household to which you have the -honour to belong. You would not therefore like to see -open spaces here and there, requiring to be filled up with -putty, or the side of the box not truly square to the back -and front. And it may be noted here, that if dovetails are -properly fitted together, the box or other article will stand -firm, even before the glue is added; but if the same are -badly cut, and put together carelessly, no amount of glue -will avail to hold the work securely; and it would have been -as well or better never to have attempted dovetailing, as -such bad work would be stronger united by nails, and in -any case is but a disgrace to the young amateur mechanic, -whose motto should always be, “<i>Whatever is worth doing at -all is worth doing well</i>.”</p> - -<p><span class="pagenum"><a name="Page_68" id="Page_68">[68]</a></span></p> - -<div class="figcenter" style="width: 400px;" id="fig29"> -<img src="images/figure29.jpg" width="400" height="550" alt="" /> -<p class="caption">Fig. 29.</p> -</div> - -<p>You will remember how you were taught to wedge up -mortice and tenon joints with glued wedges, which, becoming -part of the tenon, and rendering it larger below than -above, prevents it from being withdrawn from the mortice. -Now, a single dovetail has the same effect, and is in point -of fact of the same shape and size as the tenon with its<span class="pagenum"><a name="Page_69" id="Page_69">[69]</a></span> -wedges attached. See Fig. 29, A and B, the first being a -wedged tenon, the second a dovetail.</p> - -<p>We shall begin with a single dovetail, which is applied to -the construction of presses used by bookbinders and others, -and also domestically for house-linen. In these there is a -strong tendency to draw the sides upwards, and to tear them -from the bottom—a strain which this form of joint is exactly -calculated to withstand. The same is also used in making -many kinds of frames, where similar strength in one -direction is necessary. If you have no special need of such -at present, you should nevertheless make one or two for -practice, and to give you a better insight into their construction. -Indeed, if you cannot make single dovetails -well, you will hardly succeed in making a whole row of them -exactly alike, for joining together other articles, as drawers, -boxes, and cabinets. C of this fig. represents a bar of wood -truly squared up, and ready for being marked out. The -square is laid across it as seen, and a line drawn on each -side by its assistance, as far from one end as is the thickness -of the other piece to which it is to be attached, and a -little over (say one-eighth of an inch) which will afterwards -be neatly planed off. This is allowed merely because the -extreme angles at <i>e e</i> sometimes get damaged in cutting -out the dovetail, and if they are, they will have to be -removed. Having drawn the above line all round the -piece, divide it into three by the aid of your compasses, as<span class="pagenum"><a name="Page_70" id="Page_70">[70]</a></span> -shown, on what we may call the front and back, and then -on both these sides draw lines, <i>e e</i>, to the angle. You now -have the dovetail, or rather the pin of the dovetail, marked, -and with a fine saw you have only to cut out this piece as -you see at D, taking great care to cut accurately close to -the lines, but to leave them, nevertheless, on the edge of the -piece you are about to use.</p> - -<p>If you can saw truly, you should not have to touch these -pieces with a chisel, but if not, you must take a <i>very sharp</i> -one, and pare the wood exactly true to the lines which you -have marked. Now the dovetail made by dividing the -width of the stuff into three, as given here, will not answer -so well for pine, which is liable to split off in the line H H -of the fig. D; but for ash, beech, elm, and such like, it is a -good proportion. If the material, therefore, is pine, divide -it into four instead of three, as seen at E, and draw lines to -the angles from the two outer marks; or, without any such -division, set out equal distances from each side, so as to -give about this proportion to the pieces which are to be -cut out.</p> - -<p>Where there are a row of dovetails to be made (as in -cabinet work), even this latter measurement into four would -make them too angular, as you will learn presently. You -must now fix upright in your vice the piece in which is to -be cut the dovetail to receive this pin; and laying the latter -in place as it will be when the frame or other work is put<span class="pagenum"><a name="Page_71" id="Page_71">[71]</a></span> -together, draw round it with a sharp pencil or scriber, as -seen on the end of K (the lines <i>c d</i>, at such distance from -the end of the piece as is the <i>thickness</i> of the pin, and the -perpendiculars, <i>a b</i>, are to be drawn with the square); and -if the angles of such pin do not reach the angles of that in -which the dovetail is to be cut, as will often be the case, the -lines on the opposite side similar to <i>a b</i> must be also drawn -with the square. So you see that I was quite right in -directing you to add a square to your box of tools, even -before many other requisites of carpentry.</p> - -<p>If it is not considered desirable that the dovetail -should reach the extreme angles of the pieces, as <i>a b</i>, fig. -K, the pin piece is first marked as if for an ordinary tenon, -and the dovetailed pin marked on this, as M. When the -fellow-piece is cut out, it will then appear as N. The effect -will be the same as the last, except that the end of the pin -will be more conspicuous. A great deal depends upon the -material, and on the intended use of the finished article, -therefore you must use your own judgment, or consult that -of others better acquainted with the art than yourself. -L shows the dovetailed joint complete as last described.</p> - -<div class="figcenter" style="width: 400px;" id="fig30"> -<img src="images/figure30.jpg" width="400" height="500" alt="" /> -<p class="caption">Fig. 30.</p> -</div> - -<p>We now recur to the row of dovetails and pins—or dovetails -and <i>sockets</i>, as the part is often called which is to receive -the pins. The most common kind is that represented by A -B, Fig. 30; and as you ought now to be thinking of a larger<span class="pagenum"><a name="Page_72" id="Page_72">[72]</a></span> -tool-box, and would not like it roughly nailed together like -the first, you might try your skill by constructing one -more worthy of the name, and with a drawer or two in it. -You must begin, as before, by marking the two lines across -your work by the edge of the square, or, if you prefer it, by -your gauge, which, when set to the thickness of one piece, -will mark the others correctly; and remember to mark <i>both<span class="pagenum"><a name="Page_73" id="Page_73">[73]</a></span> -sides</i>. Then set out your dovetails, but do not make them -so angular as you did the single one; for remember you -have a whole row of them to assist in holding the work -together, and when glued, this will be of necessity a very -strong and reliable joint, if well made.</p> - -<p>Always make the pins before the sockets, and mark -round them as closely as possible, and take great care when -sawing not to break them, and if possible keep their angles -also very sharp and clean. It is solely care in these particulars, -and accurate cutting just to the gauge lines and no -further, that makes carpenters’ work generally so superior -to that of amateurs, and boys especially are generally careless, -and in too great a hurry to get the work done, that -they may go to something else. Remember, therefore, that -when you begin to hurry your work, you begin to spoil it.</p> - -<p>I have made the drawings of the three principal dovetailed -joints so plain as to render special description almost -unnecessary after the remarks already made. The second -and third, however, may need a few words, as they differ -slightly from that used in the drawer, of which a description -has been given, chiefly because the piece in which the -dovetails are, is, in this case, as thick as that used for the -sockets.</p> - -<p>Suppose the dovetails <i>and pins</i> marked out ready to be -cut. Take your marking-gauge and set the slide about a -quarter of an inch from the point, and run a line across the<span class="pagenum"><a name="Page_74" id="Page_74">[74]</a></span> -ends of the two pieces at A B, and at C D, and also at E F. -Stop at A B when you cut the sockets, and take care to get -the bottoms of these quite square and even. Cut the dovetails -or pins as directed in making the drawer, but stop on -the lines <i>e f</i> and <i>g h</i> (the latter also to be made with the -gauge on both edges of the work), thus the two pieces will, -of necessity, fit nicely together, and only a single line will -appear a little way from one corner. If all lines are made -with gauge and square, this form of dovetail may require -neatness and care, but will not be beyond the skill even -of a young mechanic. I should indeed advise that every -opportunity be taken of joining pieces of wood with tenon -or with dovetail, because, after all, these are the chief -difficulties to be encountered. If you can square up your -work, and make true-fitting joints, there is little in carpentry -and joinery that you cannot accomplish.</p> - -<p>The third example is worked exactly like the second, but -instead of leaving square the pieces projecting beyond the -dovetails and pins, these are sloped off or bevelled carefully -from the extreme corners down to the pins and sockets. -The result is, that when put together, no joint appears, as -it is exactly <i>upon</i> the angle. There is no neater or stronger -method than this of joining the sides of drawers, boxes, -trays, and such like articles. The cabinetmaker employs -no other for heavy work; only when it is very light does he -make use of a plan, the appearance of which is (when<span class="pagenum"><a name="Page_75" id="Page_75">[75]</a></span> -finished) like the last-described, but it is less trouble to -make, and less strong, yet sufficiently so for many purposes. -This method is called <i>mitring</i>, and is accomplished -in the following way.</p> - -<p>The wood (let it be for a small tray) is prepared as usual, -truly and evenly, and the ends exactly square to the sides. -If you use stuff about a quarter or half an inch thick, or -even an eighth (the first or last being suitable for such -light work), you can make a mitred joint with the help of -the gauge alone, but frequently a <i>mitre-board</i> or <i>mitre-box</i> -is used, which saves some trouble in measuring and marking. -It is well, however, that you should begin with this -trouble, and take up the easier method afterwards; especially -as it will in this case give you a simple lesson in -mathematics, and teach you some of the properties of the -figure called a square. Let us commence with this lesson.</p> - -<p>A, B, C, D, Fig. 31, is a square; the lines at the -opposite sides are parallel,—that is, they are exactly the -same distance apart from one end to the other. To make -this clear, E and F are given, which are not parallel, for -they are further apart at one end than they are at the -other. And as A B is parallel to C D, and A C parallel -to B D, so A B is perpendicular to B D and to A C, or -what we have called <i>square</i> to it, as you would find with -your square, which is made, as you know, to prove your -work in this respect. The consequence is, that the angles<span class="pagenum"><a name="Page_76" id="Page_76">[76]</a></span> -(or corners) are all alike, and are called right angles. -Understand what is meant by angles being the same size -or alike. M and H are alike, though the lines of one are a -great deal longer than those of the other; but though the -lines of K and H are the same length, the angle K is -much smaller than that at H.</p> - -<div class="figcenter" style="width: 500px;" id="fig31"> -<img src="images/figure31.jpg" width="500" height="350" alt="" /> -<p class="caption">Fig. 31.</p> -</div> - -<p>As I have gone a little into this subject, I will go a -little further, for it is as well that you should learn all -about the sizes of angles, and I only know of one way in -which to make the matter clear.</p> - -<p><span class="pagenum"><a name="Page_77" id="Page_77">[77]</a></span></p> - -<p>Every circle, no matter how small or large, is supposed -to be divided into 360 equal parts, called degrees. That -large circle which forms the circumference of the earth is -considered to be so divided. Now, if we draw lines from -all these divisions to the centre, they will meet there, and -form a number of equal angles. I have not divided the -circle P all round, because it would make so many angles -that you could not see them clearly; but I have put 360 at -the top, and then 45, which means, that if I had marked -all the divisions, there would be 45 up to that point. -Then at 45 more I have marked 90, and so on, marking -each 45th division, and from these I have drawn lines to -the centre of the circle. Now, if you understand me so -far, we shall get on famously. Look at the line from 360 -to the centre, and that from 90°, and see where they join. -This is a right angle, and this is the angle at each corner -of a square. At N, I have drawn this separately to make -it clear, and you see I have taken a quarter of the circle, -or the <i>quadrant</i>, as it is called, of 90°. And you now see -that I might extend the lines beyond the circle to any -extent, but it would make no difference,—we should still -have 90° of a circle, only the circle would be larger, as -those which are partly drawn with the dotted lines.</p> - -<p>Now, all angles are thus measured by the divisions of -a circle; the line at 45, which meets the line from 360 at -the centre, makes with it an angle of 45°, which is half a<span class="pagenum"><a name="Page_78" id="Page_78">[78]</a></span> -right angle. A line drawn at 30° would make an angle of -30 with the same line from 360, and so on right round; -only when two lines come <i>exactly</i> opposite one another, as -360 and 180, or 270 and 90, these make <i>no angles</i>—they -are but one straight line passing through the centre, and -are called diameters of the circle, a word which means -<i>measure through</i>, or across the circle. Now, the corners of -a square frame, or of a drawer or box, are right angles of -90°. At R, I have drawn such a corner of a frame, and if -I place one point of a pair of compasses at <i>e</i>, and draw a -circle cutting through the lines of the sides of the frame, -you see I should make it 90°, or a quadrant, like N. -Moreover, if I draw the sides of the frame as if they -crossed as at <i>e</i> R, I draw a small square, and the line -<i>e</i> R is the diagonal of such square: <i>e</i> R <i>is the mitred -joint I have to cut</i>. Look at T S and you will see this, -as here the two sides of the frame are represented as cut -ready to be joined together.</p> - -<p>A square has another quality: all its sides are equal, -and this is very important, and will help us in cutting out -the work. <i>x</i> Y represents the strip of wood to be properly -sloped off for a mitred joint. With a gauge such as that -just above <i>x</i>, or your regular marking gauge, set off on -the side Y a distance equal to <i>x x</i> (the <i>width of the</i> -pieces); join <i>x b</i> by a line, and you will have the right -slope. Why? Because when you measured with the gauge<span class="pagenum"><a name="Page_79" id="Page_79">[79]</a></span> -you marked the <i>two equal sides of a square, and x b is the -diagonal of it</i>, which is exactly the same as you had at -<i>e</i> R. By measuring in this way, therefore, you can, if -your strips are already truly squared up, always mark out -a mitred joint correctly. The two little angles at <i>x</i> and <i>b</i> -are also, I should point out, equal—each half of a right -angle or 45°, and the other strip or side of the frame will -make up the other half right angle, or complete the exact -square of 90°.</p> - -<p>In all this I have clearly laid down the principles of -mitred joints, and given you a lesson in mathematics. I -shall now, therefore, go on to the work of practical construction -(Fig. 32). You must be very careful to make the -edge B square to the side A, as in all other work which I -have explained to you; or, if this side is moulded like the -front of a picture-frame, you must square the edge with -the back. After having cut all the pieces, you have to -glue them and fasten them together. Warm them, and -use the glue boiling, as directed before, and quickly lay the -pieces together. To do so effectually, you must place them -flat on a board or on your bench, and having adjusted -them, you can tie a strong cord round the whole, putting -little bits of wood close to the corners, so that the string -shall not mark your work, if such marks would be of consequence. -Or you can wedge up strongly in another way. -If you look at C you will see a square representing a frame<span class="pagenum"><a name="Page_80" id="Page_80">[80]</a></span> -with eight spots round it. These are nail heads, and mark -the position of eight nails driven round but not touching -the frame into the bench. Then, having prepared eight -small wedges, drive them in between the frame and the -nails.</p> - -<p>You will find this as simple and easy a way of keeping the -frame together as any, and all must remain till the glue is -dry and hard—probably till the same hour on the following -day? Then remove the wedges and take up your frame, -which should be trim and strong. Nevertheless, you are -now to add considerably to the strength of it in one or both -of the following ways.</p> - -<div class="figcenter" style="width: 400px;" id="fig32"> -<img src="images/figure32.jpg" width="400" height="200" alt="" /> -<p class="caption">Fig. 32.</p> -</div> - -<p>With a mitre-saw or tenon-saw cut one or two slits at -each angle, as seen at D, Fig. 32, <i>e</i> and <i>f</i>. Cut little pieces -of thin wood, and having glued them, drive them into these -slits. If you saw them slanting, some tending upwards -and some downwards, it will be better than cutting straight -into the frame. Then, when all is dry, neatly trim off<span class="pagenum"><a name="Page_81" id="Page_81">[81]</a></span> -these pieces even with the frame. You may also, if the -work is of a more heavy kind, as a large picture-frame, -finish with keyed mitres, <i>g</i>. Cut a place with a chisel of -the shape here shown, about one-eighth of an inch deep, -half into one piece and half into the other. Then cut out -a key of the same form of thin hard wood, to fit exactly, -and glue it in. The shape of the key prevents the joint -from coming apart, and makes it very strong and durable. -A very large number of light boxes are made with mitred -joints, as workboxes, water-colour boxes, compass-boxes, -and such like; and you can examine these for yourself; but -you will not often see the keys at the angles, because most -of such boxes are veneered, or covered when finished with -a thin layer of some ornamental wood.</p> - -<p>I shall now proceed to show you how these joints can be -cut at once without the trouble of gauging and measuring -to find the proper angle. Therefore I shall let you into the -secret of mitring boxes and mitring boards, which, if you -had much to do of this kind, would shorten your work -considerably.</p> - -<p>Fig. 33, A, represents a mitring-board, B a mitring-box. -We must go into a little mathematics again, and try -to understand these, because, if you do so, you may devise -others, occasionally more suitable for any special work you -have in hand.</p> - -<p><span class="pagenum"><a name="Page_82" id="Page_82">[82]</a></span></p> - -<div class="figcenter" style="width: 500px;" id="fig33"> -<img src="images/figure33.jpg" width="500" height="300" alt="" /> -<p class="caption">Fig. 33.</p> -</div> - -<p><span class="pagenum"><a name="Page_83" id="Page_83">[83]</a></span></p> - -<p>First, look at D of this figure. You have a line, <i>a b</i>, -standing upon another C D, and perpendicular to it—that -is, it leans neither to the right nor to the left. It makes -two angles at <i>b</i>, one on each side of <i>a b</i>, and these are -angles of 90°, or right angles, as I explained. Now, if one -line like <i>a b</i> stands on another, these two angles are -<i>together</i> equal to 180°, or twice 90°, whether this line is or is -not upright or perpendicular to the other. Look at fig. C. -Here you have the line <i>x x</i>, and standing on it several -others; one, <i>a b</i>, is upright or perpendicular, making with it -two angles of 90° each, or 180° together. Now, take <i>f b</i>, and -suppose this to make 45° on the right-hand side, you see it -makes therefore a proportionately larger angle on the other. -It makes, in fact, an angle of 135°. But 135° added to 45° -equals 180°, which is the same as before, and whichever -line you take, the angles together made by it at <i>b</i> will -equal 180° of the circle—that is, they will equal two right-angles.</p> - -<p>Now, if I take the fig. D again, and carry on the line -<i>a b</i> right through <i>c d</i>, where it is dotted, two angles will be -made on the other side of <i>c d</i>, which will each be right -angles of 90° as before, so that all the four angles thus -made are equal. It follows from this, that whenever any -two lines cut each other—E Q and R S for instance—the -angles at T <i>equal</i> four right angles, no matter whether the -lines are or are not perpendicular to each other: and what -is more (and what I specially want you to note), the<span class="pagenum"><a name="Page_84" id="Page_84">[84]</a></span> -<i>opposite</i> angles <i>are equal</i>—<i>i.e.</i>, the two small ones, or the -two large ones.</p> - -<p>The action of a mitre-block or mitre-box depends upon -the principles here laid down, so you see that although few -carpenters understand much about mathematics, and simply -work as they were taught, without knowing or caring why, -those who planned the method of work, and invented -mitre-boards and such like devices to shorten work and -lessen labour, must have understood a great deal about -such things. And so it is generally, as you will find with -inventions: things look easy enough, and natural enough, -when we see them every day; but it has taken a great deal -of thought and sound knowledge to invent them in the -first place, and a great deal of practical experience to construct -them so neatly. Even a common pin goes through -such a number of processes as would surprise you, if you -have never been able to see them made.</p> - -<p>Look carefully at A. It represents a block of wood, -about 1½ or 2 inches thick, and 3 or 4 wide, firmly screwed -on the top of a board 1 inch thick. The length is about -18 inches. Two saw-cuts are made with a tenon-saw, right -through the block to the board, at angles of 45° with the -line <i>a b</i>. These are guides for the saw to work in. The -wood to be cut is laid against the edge of the block, and -rests on the board, and the saw is then applied in one of -the grooves while the wood is being cut by it. Let H be<span class="pagenum"><a name="Page_85" id="Page_85">[85]</a></span> -such a piece. If the saw is put in the left-hand slit, it will -cut it like <i>y</i>; if in the other, it will cut it the other way, -like <i>x</i>; and thus, if a piece is taken off at each end, it will -be as you see, ready to become one side of a frame. Now, -examine K, which shows all the lines or edges of the -mitring-board, as seen from above, with the strip <i>a b</i> sawn -across in the line <i>c a</i>. The lines <i>a b</i> and <i>c a</i> cross each -other, making the opposite angles equal; and as one angle -is 45° the other must be 45° also, so that the right-hand -side of the strip is correctly cut. But so also is the other -end, and if we turn it over, it will exactly fit, and the two -will form two sides of a square. I could prove to you that -the second strip contains angles exactly similar to the first, -but you ought to be able now to detect the reason for yourself, -and I do not want to teach you more mathematics at -present, as I am afraid you are tired of these, and will -want to go on with the real work of fitting and making. -I have, however, said enough, I think, to make you comprehend -<i>why</i> the two saw-cuts must be at an angle of 45° with -the edge of the top board.</p> - -<p>Perhaps you wish to make your own board, however, and -would like to know an easy way to get the saw-cuts at the -right angle? I shall therefore show you how to do this, -but you must be very exact in your workmanship. A B, -Fig. 34, is the piece of thick board as seen from above, and -close to it is a perspective view of the same which shows<span class="pagenum"><a name="Page_86" id="Page_86">[86]</a></span> -the thickness. Set off a distance, A E, equal to A C, and -join C E. The dotted line shows you that C E is the -diagonal of a square, and the angles at C and E are consequently -each 45°; but we do not want this line to end at -C, it is too exactly at the corner for convenience. Measure, -therefore, a distance, E <i>b</i> and C <i>a</i>, equal, and join <i>a b</i>, -which will be the place for the saw-cut; and the other can -be marked out in exactly the same way. <i>a x</i>, in the perspective -view, must be carefully marked by the help of the -square. Take care to mark the line on the bottom board, -where the edge of this upper thick piece will fall, and screw -the two firmly together. If the edge and face of the thick -piece are not truly square to each other, the mitres cut thus -will not be correct; but, if all is well made, they may be -glued at once together, no paring of the chisel being necessary -or desirable.</p> - -<p>The mitre-box, Fig. 33, B, is on precisely the same principle, -but is chiefly used to cut narrow strips not over 2 -inches wide; it should be neatly made of mahogany, half -an inch thick. There is also generally made a saw-cut -straight across, at right angles to the length of the box or -board, which is convenient in sawing across such strips of -wood, as it saves the necessity of marking lines against the -edge of the square: of course, it is specially used where a -large number of strips have to be cut square across. In all -these you observe one saw-cut leaning to the right, the<span class="pagenum"><a name="Page_87" id="Page_87">[87]</a></span> -other to the left. This is necessary when picture-frames -or moulded pieces have to be cut to 45°, because you cannot, -of course, turn such pieces over and use either side, -which you can do when the piece has no such mouldings.</p> - -<div class="figcenter" style="width: 500px;" id="fig34"> -<img src="images/figure34.jpg" width="500" height="325" alt="" /> -<p class="caption">Fig. 34.</p> -</div> - -<p>Several modifications exist of mitring-boards; some -arranged for sawing, and some for planing; and where -thousands of frames have to be cheaply made, the angles -are cut off with circular saws, of which I need not speak -particularly here, but which I shall probably have to -describe in a future page. In Fig. 34, K, I have shown -one corner of a simple picture-frame, covered with what is -called rustic work, that is—short pieces of oak, ash, or -other wood cut from the tree, left with the bark on, or<span class="pagenum"><a name="Page_88" id="Page_88">[88]</a></span> -peeled and varnished. These are nailed on with small -brads; and, if well assorted and arranged, this will have a -very neat appearance, suiting well for rooms fitted up in -oak, as many studies and libraries are. In picture-frames, -however, a rebate (called rabbit) has to be made at the -back, like L, in which the picture with its glass and back-board -has to rest; and this requires a special plane. The -front also is always either sloped off or moulded. I shall -therefore make this kind of work the subject of my next -chapter, and describe the operations of rebating, grooving, -tongueing, and moulding.</p> - -<div class="figcenter" style="width: 250px;"> -<img src="images/footer2.jpg" width="250" height="125" alt="" /> -</div> - -<hr /> - -<p><span class="pagenum"><a name="Page_89" id="Page_89">[89]</a></span></p> - -<div class="figcenter" style="width: 500px;"> -<img src="images/header3.jpg" width="500" height="110" alt="" /> -</div> - -<h2 id="CHAPTER_VI"><span class="smcap">Chapter VI.</span></h2> - -<div> -<img class="dropcap" src="images/dropcap-t.jpg" width="100" height="120" alt="" /> -</div> - -<p class="dropcap">These operations, which are frequently required -in carpentry, are done on a small scale by -planes. On a larger scale, circular saws and -other machinery are widely and extensively -made use of for the same purpose, as being much more -rapid and economical. Of course, the young mechanic will -employ the more usual method, and the present chapter -will therefore treat of the planes necessary for the above -work, and the method of using them.</p> - -<p>The common rebate or rabbit plane comes first. This is -of various widths; an inch being a very useful size. It is -different in many respects from the smoothing-plane, being -made with a single iron only, which is so arranged as to -reach into angular recesses, which could not be touched by -the ordinary plane, of which the iron does not extend quite -to either side of the sole. Fig. 35, A and B, will illustrate<span class="pagenum"><a name="Page_90" id="Page_90">[90]</a></span> -this. A represents the plane as seen from above and at -one side, B gives the perspective view of the sole, C represents -the iron, D the wedge. Let us suppose a rebate -required upon a strip 1 inch thick, the same to be half an -inch wide and deep. A gauge is first set to the required -distance, and a line is marked on both faces, as a guide for -the action of the plane. After a little practice it will be -found easy to guide the entry of the plane with the left -hand, grasping it so as partly to overlap the sole, and thus -determine the width of the cut, which must not at first be -carried to the full width required, but may be brought -within an eighth of an inch of such gauge line, and the -material removed sometimes from one face of the rebate -and sometimes from the other, taking care to keep it nicely -square.</p> - -<div class="figcenter" style="width: 500px;" id="fig35"> -<img src="images/figure35.jpg" width="500" height="275" alt="" /> -<p class="caption">Fig. 35.</p> -</div> - -<p>At first it is an easier plan to nail on with brads a<span class="pagenum"><a name="Page_91" id="Page_91">[91]</a></span> -strip of wood accurately planed, which in this case, as the -sole of the plane is 1 inch wide, must cover it from end to -end to a width of half an inch. This will prevent the possibility -of going too deep into cut, and insure the correctness -of the rebate, Fig. 35, H. The injury to the sole will -not be great if small brads are used, but at the same time -it is better to learn the art of using the hand as a guide, -which is the more general method of the working carpenter. -As for the use of rebates, there are few pieces of -cabinet-work or joinery in which they are not found, and -as stated in the previous chapter, no picture-frame can be -made without them. The shavings which escape from the -rebate-frame do not rise out of the top, as in the smoothing-plane, -but from the side, which is hollowed out for the purpose, -as seen in the drawing.</p> - -<p>The skew rebate-plane is made like the preceding one, -but the iron, instead of standing at right angles to the -sides, is placed at an angle. With this you can plane -across the grain of the wood.</p> - -<p>The next plane to be noticed, is that with which -grooves are cut, such as you will often see in the sides -of book-shelves, in which the several shelves slide. The -same is done where two boards are to be joined lengthwise, -and there is danger of their becoming separated -as the wood shrinks in drying. The panels of doors, -too, are slid into similar grooves in the styles and<span class="pagenum"><a name="Page_92" id="Page_92">[92]</a></span> -rails of the framework, and there are innumerable other -cases in which this mode of work is carried out. These -grooves are generally cut with the plough, a curious-looking -tool, by no means like a plane in appearance, but of great -use to the carpenter. Of course, we require various widths -of such grooves, according to the special purpose intended, -and these are determined by various widths of the cutting -irons, which, however, all fix into the same stock; a dozen -or more of such irons are sold with a single plane.</p> - -<div class="figcenter" style="width: 400px;" id="fig36"> -<img src="images/figure36.jpg" width="400" height="450" alt="" /> -<p class="caption">Fig. 36.</p> -</div> - -<p>In Fig. 36 is a set of drawings explanatory of the above -tool. The central part, or stock, is that which corresponds -to the same in other planes, and it is only modified to suit -the other parts, which simply act as guides or gauges regulating<span class="pagenum"><a name="Page_93" id="Page_93">[93]</a></span> -the distance of the grooves from the edge of the -board, and the depth to which they are to be cut. When -the arms, A A, are removed, you have the plane as it appears -with a brass fence, <i>b</i>, at one side, which can be raised or -lowered at pleasure, and set at any point by the screw C; <i>d</i> -is an iron plate which acts as the sole of the plane, the -cutting edge being set to project a very little way below it.</p> - -<p>The arms A A carry the fence <i>g</i>, which is flat on the -inside next the plane, and moulded (merely for appearance -sake) on the outside. The arms slide in two holes in the -body of the plane, and can be drawn out at pleasure, and -fixed by little wooden wedges, <i>e e</i>. Thus, while in use, the -fence rubs along the edge of the board, while the groove is -being cut at such distance as the fence is fixed, and to such -a depth as is allowed by the position of the brass check -or guide. Complex, therefore, as this tool appears, it is -not so in reality. We shall presently describe a chest of -drawers or cabinet calculated to receive small tools, or -specimens of coins, shells, and such like, in which another -kind of grooving-plane has to come into use, called (with -its fellow, which makes a tenon to fit such groove) a match -plane. This is of extensive use, less expensive than the -plough, and on the whole more likely to be useful to the -young mechanic. Indeed, although the plough has been -here described and illustrated, it is not by any means to be -considered essential, and its purchase may well be deferred<span class="pagenum"><a name="Page_94" id="Page_94">[94]</a></span> -until other tools of greater importance has been effected. -The side or sash fillister to be presently described, for instance, -would be more useful.</p> - -<div class="figcenter" style="width: 500px;" id="fig37"> -<img src="images/figure37.jpg" width="500" height="500" alt="" /> -<p class="caption">Fig. 37.</p> -</div> - -<p>Fig. 37 is such a cabinet, with six drawers, dovetailed at -the corners as usual. The bottom, however, projects beyond -the sides, so that the latter are not made lower than -the back, as was the case with the table-drawer previously -described. The top and sides may be of mahogany, the -back and bottom of pine (stained or not at pleasure), or if -cost is an object, the whole may be of any other wood; but -the grooves in which the drawers slide, can be cut more<span class="pagenum"><a name="Page_95" id="Page_95">[95]</a></span> -sharply and neatly in harder wood than pine—birch, for -instance, which is very fit for the purpose, and will take a -good polish. The outer case is first made like an open -box. The dimensions may be regulated according to the -intended use, but generally the drawers increase in depth -downwards. The top and bottom overlap the sides, the -latter to a somewhat greater width than the former. The -sides can therefore only be dovetailed to the back; the -bottom may be attached with screws, and the top likewise, -but the holes must then be plugged to conceal them. If -the whole is of deal, and to be painted or veneered, this -would be the best plan; but if the top is of mahogany, it -is not so easy to fill up the holes above the heads of the -screws so as to thoroughly conceal them. If, however, you -have no plough to cut a groove to let the sides and back a -little way into the top, glue alone will not hold sufficiently. -In this case smaller holes may be made to admit 2-inch -brads to assist the glue, such holes being easily filled with -putty stained to imitate mahogany.</p> - -<p>The peculiarity of the drawers consists in their meeting -each other quite closely when shut, without the intermediate -divisions ordinarily seen. Hence the necessity for -a different arrangement of the sliding surfaces as before -referred to. The insides of the case have <i>five</i> grooves -ploughed across them, as seen at C of this figure, the -sixth drawer only being made as usual to slide upon the<span class="pagenum"><a name="Page_96" id="Page_96">[96]</a></span> -bottom of the case, and having its sides made lower than -the back for this purpose.</p> - -<p>In the grooves thus cut, the projecting part of the -bottom of the drawers is made to fit and slide, and they -will run more smoothly if cut so that the grain of the -wood shall run across the bottom, from front to back, and -not from side to side. The bottom of the drawer must not -come below the level of the front, but either the front -should be rebated to take one edge of it, as seen at E, -which is the best way, or a slip of wood should be glued -along as at F, on which that edge may rest, and to which -it can be attached. D exhibits this distinctly, as it is -drawn as if the nearest end was removed to show the -position of the other parts. The bottom, therefore, will be -let into the front, and nailed under the back and sides, and -will project rather less than half an inch each way, to fit -the grooves in which it is to slide. Another way to effect -the same is to make the drawers as usual, with no such -projections, and to nail a strip to run in the grooves in -the middle of the side pieces, or, if preferred, near the -top. The effect is, of course, the same, and such strips -being planed up nicely, with the grain running lengthwise, -will cause the drawers to work in and out very -smoothly.</p> - -<p>There is no neater way than this to make a cabinet; and -sometimes the whole is closed with a panelled door, for<span class="pagenum"><a name="Page_97" id="Page_97">[97]</a></span> -which purpose the case is left to project beyond the -drawers. Unless well supplied in the matter of planes, -which is hardly to be expected, you will not be able to cut -the grooves in the side of the outer case in any way but -the following, which, however, will answer very well when -the piece in which they are to be cut is not above 9 inches -or 1 foot wide. Mark out the places, spacing them with -the greatest care, and cut just within the lines with a tenon-saw; -then cut out with a chisel the narrow piece which -intervenes. There is a plane called a routing-plane used -for this by cabinetmakers and joiners, but you may as well -exercise your ingenuity to do without it. If you have a -plough, you may remove the fence, and let it follow up the -saw and chisel, but it will be hardly required if you use the -chisel carefully.</p> - -<p>I shall now introduce to your notice another very excellent -plane, called a side or sash fillister, for cutting rebates -of any required depth and width. It is very like the plough -in appearance, with a similar wooden guide or fence on two -arms to regulate the width, and another of metal, moved -by a screw at the top, to regulate the depth of the cut. -Fig. 38, A, shows one side of this plane, and B the other. -The cutting edge comes down to the level of <i>c d</i> in fig. A; -the fence, of which the edge is seen at <i>h</i>, will draw up to the -level of <i>a b</i>, or lower to that of the edge. This plane, -therefore, is but a more complete rebate-plane, fitted with<span class="pagenum"><a name="Page_98" id="Page_98">[98]</a></span> -guides for depth and width. It does its work very perfectly, -and is of extensive use.</p> - -<div class="figcenter" style="width: 400px;" id="fig38"> -<img src="images/figure38.jpg" width="400" height="500" alt="" /> -<p class="caption">Fig. 38.</p> -</div> - -<p>I have given descriptions of these planes, although the -young mechanic will not at first possess them, as they are -somewhat expensive, because I feel it as well to let him -know how work is done by the trade, and why it is that -such work is effected more rapidly and better than he himself -can do it; but at the same time it is far better that he -should, for a long time, work at a disadvantage, by using<span class="pagenum"><a name="Page_99" id="Page_99">[99]</a></span> -few tools, and those of the simplest construction, before -taking in hand others which cost a good deal of money, -which might often be better spent. A look back over these -pages will show that with a long (or jack) plane, a smoothing-plane -and a rebate-plane, all the work previously -alluded to can be done. As, however, I am writing upon -the subject of planes, I may as well mention two more—match-planes -and beading-planes—to which may be added -those for moulding, being an extension only of the last -named. Match-planes are always in pairs. Their use is -to cut, the one a groove, Fig. 39, A, the other a tenon or -tongue, or feather, as it is sometimes called, as Fig. 39, B, -down the long sides (with the grain) of boards that are to -be joined lengthwise (Fig. 39). If the plough is used, a -groove is cut in both pieces, and a slip of board planed up -to fit them; either method will answer equally well. -When boards joined thus shrink, the tongue or slip fills up -space.</p> - -<div class="figcenter" style="width: 400px;" id="fig39"> -<img src="images/figure39.jpg" width="400" height="200" alt="" /> -<p class="caption">Fig. 39.</p> -</div> - -<p>There is no necessity for illustrating the planes used for<span class="pagenum"><a name="Page_100" id="Page_100">[100]</a></span> -beading and moulding after the description already given -of others. The irons, instead of being flat, are filed into -grooves and hollows of the required pattern, and of course -transfer their own form to the wood upon which they are -used. They are held on the slope of the moulding to be -cut. When blunt, they have to be sharpened with slips of -oilstone, which can be had for the purpose, of square and -round section; sometimes they are sufficiently soft to be -filed into shape, but a keen edge cannot thus be obtained. -Mouldings, however, are generally finished off with fine -sandpaper. They are always planed lengthwise of the -grain in long strips, and are cut to the required lengths -(generally with mitres). When very broad, they are made -up of several narrower ones, glued side by side. The -young mechanic had better get them cut for him by some -friendly carpenter, as it is hardly worth his while to -buy planes for which he will have comparatively little -use.</p> - -<p>I shall conclude these papers on carpentry by describing -the method of making such a door as would suit the cabinet -already described, especially as it will explain the way in -which all panelling is done, whether for doors, shutters, or -other similar articles. Panelling is indeed of very general -application in every household, and it is well worth while -even for the young mechanic to learn how it is accomplished. -It is absolutely necessary, however, that he<span class="pagenum"><a name="Page_101" id="Page_101">[101]</a></span> -should be possessed either of a plough or match-planes for -routing out the grooves in which the panels slide.</p> - -<p>Nearly all panels have a beading or a moulding running -round them as a finish.</p> - -<div class="figcenter" style="width: 400px;" id="fig40"> -<img src="images/figure40.jpg" width="400" height="475" alt="" /> -<p class="caption">Fig. 40.</p> -</div> - -<p>Fig. 40 illustrates the method of panelling. A, B, C are -the styles, D, E, F, G the rails. The mortices and tenons -are cut as usual. The inside edges of C, B, D, G are then -grooved with the plough, and both edges of the other -pieces. The panels are carefully squared up, and then -bevelled off at the edges so as to fit the grooves. To put -such a door together, A, D, G, E, and F would be first<span class="pagenum"><a name="Page_102" id="Page_102">[102]</a></span> -arranged, then the panels slid in from the outside, and -afterwards the styles B and C put in place. The part -beyond the outer mortices in the latter pieces, which are -left for safety in cutting these mortices, and to prevent -splitting when D and G are driven home, are not cut off -until the glue is dry. The process is simple, but it requires -great care, both in setting out the various measurements, -and in squaring up the different pieces composing the -whole. After the whole is dry, strips of moulding, cut to -mitre-joints at the corners, are nailed on with brads round -the panels to give the whole a finished appearance.</p> - -<p>In the above examples, in which I have gone from the -more simple to the more complicated, are comprised the -main principles of the art of carpentry. At any rate, when -the young mechanic can do <i>as much</i>, he will be able to -accomplish a great deal more.</p> - -<div class="figcenter" style="width: 275px;"> -<img src="images/footer5.jpg" width="275" height="125" alt="" /> -</div> - -<hr /> - -<p><span class="pagenum"><a name="Page_103" id="Page_103">[103]</a></span></p> - -<div class="figcenter" style="width: 500px;"> -<img src="images/header4.jpg" width="500" height="110" alt="" /> -</div> - -<h2 id="CHAPTER_VII"><span class="smcap">Chapter VII.</span></h2> - -<div> -<img class="dropcap" src="images/dropcap-t.jpg" width="100" height="120" alt="" /> -</div> - -<p class="dropcap">There are a number of useful and ornamental -articles which cannot be made with the carpenter’s -tools alone, but which need a lathe for their -construction. Wooden boxes of circular section, -wooden and metal wheels and pulleys, ornamental chair and -table legs, and a countless number of similar articles, all -depend upon the skill of the turner. Models too of engines -and machinery of all sizes and shapes, bring the lathe into -constant requisition.</p> - -<p>No one can say to whom this machine is to be attributed. -Probably it has been developed by slow and imperceptible -steps, from the potter’s wheel to its present elaborate and -perfect form. As for the part that old Dædalus had in it, -I believe he had just as much to do with it as he had with -the saw, which he is said to have invented from seeing the -backbone of a fish. Now, the backbone of a fish is not a<span class="pagenum"><a name="Page_104" id="Page_104">[104]</a></span> -bit like a saw, but the jaw of a shark is, and very quickly -it amputates legs, arms, and heads, when unfortunately -the chance is given to it. We need not, however, stay to -discuss this unimportant point; we will leave it to the -researches of the Antediluvian Society, or Noahican Brethren, -or any other known or unknown learned body, and -proceed to consider the lathe as it is now generally constructed—the -ambition of boys, the delight of adult -possessors, and, to the writer, “gem of gems!”</p> - -<p>At the very time I write, I am engaged in fitting up two -lathes; one of which is for just such a “young mechanic” -as this book is intended to instruct. The bed will be of -dry hard beech, the fly-wheel of iron turned up with five -grooves or speeds, as they are called. The heads, which are -the only really important part, are to be made by a well-known -London maker, whose work is sure to be the best -possible at the price afforded. Nevertheless, this lathe will -cost several pounds, although it is to be fitted for hand-turning -only, and it is possible in London to find a much -cheaper (not better) article.</p> - -<p>When I was myself a “young mechanic,” so many years -ago that I find I do not quite like to count them, I had a -lathe at £2, rather shaky, wooden fly-wheel, wooden head—not -at all the thing to recommend. Then I had another -made by a gunsmith—all iron—for it was what is called -a triangle-bar lathe; the bed being a bar of triangular<span class="pagenum"><a name="Page_105" id="Page_105">[105]</a></span> -section, on which the heads or poppits slid, and also the -rest. I think now it was not a bad lathe; but I am afraid -the work I did on it was scarcely first-class; and I sold the -machine one fine day under the impression that if I had a -better I should do better work. This, however, proved a -terrible fallacy; so I set myself upon high as a warning to -young mechanics, who always fancy that their clumsy, bad -work is due to some fault in their tools, whereas, after all, -it is generally their own.</p> - -<p>Well, I had a succession of lathes, after that triangle-bar -one had passed into oblivion, by various makers; some -good, some indifferent, some for heavy, and some for light -work; and I fancy I am now fairly able to give an opinion -upon the merits or demerits of any particular lathe which -may come under my notice.</p> - -<p>I was going to write a piece of advice, “<i>Don’t give too -much for a lathe</i>,” when I remembered that I was scribbling -for the edification first of boys; and experience tells me -the caution is by no means generally necessary, few boys’ -pockets being very heavily lined, owing to the constant claims -upon them for peg-tops, knives, string, and etceteras—not -to say lollipops and bulls’ eyes, and similar unwholesome -luxuries.</p> - -<p>I suppose, however, I must give some idea of cost, if -only as a partial guide; but all depends upon the special -object for which the lathe is to be used. If for models, for<span class="pagenum"><a name="Page_106" id="Page_106">[106]</a></span> -instance, it would not be so expensive as if it was desired -for elaborate ornamental work in wood or ivory, when the -young mechanic has grown whiskers, and become an adult -enthusiast at this delightful recreation. For there are all -kinds of lathes to be had; some that will answer well for -beginners, and for rough work in after years; some beautifully -finished, intended to be used first for simple hand-turning, -but which are of best construction, and therefore -worth adding to from time to time; and if carefully used, -will descend in good order from father to son. Then there -are lathes for heavier work, and for screw cutting and -engine making, fit for engineers; and others of minute -size and exquisite finish, adapted to the special requirements -of watch and clock makers—lathes you could put -in your waistcoat pocket.</p> - -<p>Now, if I were sure you would be very, very careful, I -should like to recommend a good lathe, worth adding to as -you grew more and more experienced; but these, even of -simplest make, are costly, and not within reach of half my -readers. I shall therefore say—get a good, plain, strong -tool that will bear a little rough usage, and which will cost -you as little as it is possible to make them for: and if you -find, after a year or two, that you are becoming a proficient, -and therefore not so likely to damage a <i>good</i> lathe, you can -set this, your first, on one side, and let it become your <i>hack</i> -to do any odd jobs, and buy yourself both a larger and a<span class="pagenum"><a name="Page_107" id="Page_107">[107]</a></span> -better one. I know this will be a <i>double</i> outlay; but experience -tells me it will be the best way and the cheapest -in the long run. Perhaps you may like to go on as you -are. Your small lathe may prove an accurate one, and -quite sufficient for your need. In such case, of course, a -new one will not be required at all. But if it should be -otherwise, and circumstances allow you to improve upon -it, you may rest assured your old friend will be ever a -handy assistant, and save your better lathe very considerably -in many ways.</p> - -<p>You can get a lathe for about $20 to $25, with iron -bed complete; and I really think it impossible to obtain a -cheaper one. Of course it will be small, and of the plainest -possible construction. It will, nevertheless, answer for -light work in wood and metal, being designed to assist the -young mechanic in making model engines and similar -curiosities. From this you may go, pound by pound, to -good, serviceable tools; and these to a £300 lathe for rose -engine-work, and elaborate ornamentation in ivory and -other costly materials. Most probably I shall be able to -give you a catalogue or two at the end of this book, published -by makers of such lathes, and you can then judge of -the probable cost of your workshop. The drawing of the -lathe (Fig. 41) will be readily understood even by those -boys who have had no opportunity of seeing any work of -this kind. There are, however, few towns or villages in<span class="pagenum"><a name="Page_108" id="Page_108">[108]</a></span> -which a lathe does not exist, and may not be examined by -any boy who desires to learn its construction and use. Its -object is to give rotary movement to any material it is -desired to form into a circular or cylindrical shape.</p> - -<div class="figcenter" style="width: 500px;" id="fig41"> -<img src="images/figure41.jpg" width="500" height="600" alt="" /> -<p class="caption">Fig. 41.</p> -</div> - -<p>Motion being given to the fly-wheel by means of the<span class="pagenum"><a name="Page_109" id="Page_109">[109]</a></span> -treadle and crank, is communicated to the pulley upon -the mandrel. Upon the screw of this mandrel, B, the work -is fixed; being usually held in a chuck suited to its particular -form, but sometimes it is screwed directly upon the -mandrel. The rest, C, is then fixed near it, and the tool is -supported thereon and held firmly while the work revolves -against it. All this is easy to understand—it is <i>not</i> so easy -to carry it into practice. Attention to the following directions -will enable the young mechanic to become a good -turner in course of time; but the art cannot be practically -learned in a day, and it needs experience and considerable -practice to become anything like a proficient.</p> - -<p>If the construction of the lathe itself is understood, the -first consideration is what tools and chucks are necessary. -I shall speak of the latter first, as little or nothing can be -done without them. First comes the prong-chuck, for soft -wood (Fig. 41, A). This, like all others, is made to screw -upon the mandrel. Its use is to hold one end of any piece -of wood while the other is supported by the point, E, of the -poppit, H, which poppit can be moved at pleasure along -the lathe-bed, and fixed at any given place by a hand-nut -below. The point itself can be advanced or drawn back by -turning the handle, K. A piece of wood thus mounted -must of necessity revolve with the mandrel, because, -although it can and will turn round upon the point of the -back poppit, it cannot do so upon the fork or prong, which<span class="pagenum"><a name="Page_110" id="Page_110">[110]</a></span> -enters and holds it securely. This chuck, or one of the -same nature, is always used for cylinders of soft wood, -which can be supported at both ends, such as tool-handles, -chair-legs, and other work not requiring to be hollowed -out.</p> - -<p>It sometimes happens, however, especially if the work is -at all rough, or considerably out of truth, that the piece -slips round upon the fork or prong, especially if it does -not enter deeply enough; and in addition, tool-handles and -round rulers, and many articles that have to be similarly -supported at both ends, are made of hard wood, into which -this prong will not readily enter.</p> - -<p>In such cases, and indeed as a general substitute for the -first, a chuck called a “cross-chuck” is to be used (Fig. -41, L, M). The <i>centre of the little</i> cross (which is of steel, -and fits into the same square or round hole in the socket -which carries the prong, and which is also used to hold -drills, pieces of iron rod which are to be turned, and other -articles) is made to revolve in the precise axial line of the -mandrel, or to run <i>true</i> with it, as it is called. The arms -of the cross are to be imbedded in the work, which is best -effected by making in the latter two saw-cuts at right -angles with each other (Fig. 41, N), which represents a -piece ready for mounting.</p> - -<p>The next chuck is equally necessary (Fig. 41, O). It -is a taper screw of steel, fixed in a socket which can be<span class="pagenum"><a name="Page_111" id="Page_111">[111]</a></span> -attached to the mandrel. Two sizes of this chuck would be -useful for a large lathe, but for such a one as will probably -be purchased by the young amateur, one only, with a screw -of medium size, will suffice. The use of this chuck is to -hold pieces which only require to be supported at one end, -so that a tool can be used to work upon the other, either to -mould it into the required form, or to hollow it out for a -box or bowl. Of course you might screw such work on the -mandrel-nose itself, but it would make a very large hole in -the end, whereas this taper screw only requires a moderately -sized gimlet-hole. It is therefore a much more convenient -way of attaching work to the mandrel, and is of -extensive use.</p> - -<p>The cup-chuck is the last required. It is sketched at P, -and is sometimes of iron, but generally of brass. There -are several sizes made and sold with lathes, but you need -not have at most more than one or two, as I shall show you -how to make wooden ones, which answer as well, if not -better. The flat plates, R, R², can scarcely be called -chucks, but they generally come into the list of such. The -latter has five projecting points, which, sticking into such -a thing as a flat-board (like a bread-platter, or round -pulley), hold it sufficiently firm when the back centre is -brought up against the other side of the piece, to allow of -its being turned. The other is merely a flat plate with -holes in it, through which screws can be passed from<span class="pagenum"><a name="Page_112" id="Page_112">[112]</a></span> -behind into any odd bit of wood of 2 or 3 inches in thickness, -whereby a chuck can be quickly made to suit any -required purpose. Two or three of these would be convenient, -one of which should be nearly as large as the lathe -will carry; and in this one a great many holes and slots -should be made. This is called a face-plate, and, in addition -to the ordinary screws, whereby pieces of wood are -attached to it, it is fitted with clamps and bolts of various -forms, for the purpose of holding securely upon its face all -kinds of flat works in wood or metal,—such as cog-wheels, -which have to be bored out and faced. The young model-maker -will find a face-plate of great service. The larger -one should be of iron, as it will be cheaper than brass.</p> - -<p>We now pass on to chucks for metal turning. These are -of various shapes. First in order comes the centre chuck -and dog, for holding rods of iron which can be supported -at both ends. The commonest form is represented -in Fig. 41, S, T. S is such a face-plate almost as I have -described, but it has a pin projecting from it, and also a -steel centre-point. The latter is often made to screw out -and in, which is the best plan. The pin can be slid to any -point in the face-plate, and clamped by a nut at the back. -T is called a dog, and of these two at least will be required, -if the young mechanic intends to work in metal.</p> - -<p>The way of using these is shown at T². The rod of iron -has a hole drilled at each end, as nearly in the centre as<span class="pagenum"><a name="Page_113" id="Page_113">[113]</a></span> -possible. It is first indented with a punch, then a drill is -put into the drill chuck, and one end of the rod brought -against it as it revolves, while the back poppit centre-point -is screwed against the indentation at the other end. A -little oil is applied to the drill to assist its working, and the -rod itself is prevented from turning round either by grasping -it with the hand or screwing a hand-vice upon it, so -that this comes against the bed or the rest; or it can be -held in the hand, which has one advantage, namely, that -the operator can feel exactly what is the resistance caused -by the drill, and can regulate the pressure accordingly. The -screw of the poppit is, of course, to be very slowly and -steadily advanced during the process. All <i>drilling</i> in the -lathe is done in this way, but in boring out long holes, the -action is often reversed, the work being kept in motion -while the tool is advanced, without being allowed to revolve. -You need not bore more than one-eighth of an inch for -light work, but must do the same at each end of the rod. -The holes thus made should be of such a size as not to let -the extreme end of the back centre-point touch the bottom, -or it will soon be worn down and blunted;—remember this -in all future work.</p> - -<p>Supposing the rod to be thus bored at each end, place -the centre-chuck upon the mandrel, instead of the drill-chuck, -and mount the bar between this and the point of the -back-centre. Thus placed, it will be accurately supported,<span class="pagenum"><a name="Page_114" id="Page_114">[114]</a></span> -but if the lathe is put in motion, it will not turn round. -Now come into use the little dogs. Remove the bar, -and choosing a dog of which the open part is tolerably -near the size of it, slip it over the end about half an inch, -and there fix it by tightening the little screw, which, you -observe, will drive the bar as far as possible towards the -smaller part of the opening, and when it can go no farther, -will secure it as in a vice. It is a good plan to file a slight -flat upon the bar, just where the screw of the carrier will -come. Now replace the bar, and when the lathe is put in -motion, the tail of the carrier should come against the -projecting pin in the face of the face-plate, which will -compel the iron to go round with it. This is the way all -bars of metal are mounted. I shall not tell you yet how -they are to be turned, because this would interfere with -the order of my description.</p> - -<p>To mount in the lathe such pieces as cylinders of engines, -which require to be bored, or any other objects which have -to be turned on one or both faces, the young mechanic -must make wooden chucks, and bore them out exactly to -fit the article and hold it securely. There are metal chucks -expressly made to take all work of this kind, and which -are so contrived that they will also hold it truly central, -but they are costly, and need not be obtained with the first -lathe—at any rate, not until <i>absolutely required</i>, and that -will be, I know, a long time hence; ay, a <i>very</i> long time,<span class="pagenum"><a name="Page_115" id="Page_115">[115]</a></span> -for many good workmen have never even <i>seen</i>, much less -possessed one of them. Perhaps I may draw and explain -one in a future page, as well as some other chucks, which -it is not necessary to notice here.</p> - -<p>The chucks then absolutely necessary are these—</p> - -<div class="hanging"> - -<p>1. <span class="smcap">Square Hole Chuck</span>, which will take the prong, the cross, the drills, and -short bits of iron to be turned.</p> - -<p>2. <span class="smcap">The Taper Screw.</span></p> - -<p>3. <span class="smcap">Flange</span> or <span class="smcap">Face Chucks</span>, one with five points, and two with holes for -screws, also one larger for a face-plate.</p> - -<p>4. Two or three <span class="smcap">Cup-chucks</span> (I can, however, scarcely call these <i>absolutely</i> -necessary).</p> - -<p>5. <span class="smcap">Chuck for Iron</span>, viz., face-plate with centre-point, and two dogs to -take iron from 1 inch diameter down to quarter-inch. These should -have pear-shaped openings, not round; any blacksmith can make them, -but somehow they do such work generally in a clumsy fashion; and -they cost but 35 to 75 cents, according to size, beautifully made with -turned screws.</p></div> - -<p>Now as to tools. Their name is legion—tools for iron, -brass, ivory, hard and soft wood; and many an odd shilling -will be well laid out from time to time in adding to the -stock. Happily those most needed are not costly—about -$3 a dozen without handles, which latter may be had at -10 cents each and upwards, according to the material and -finish, all with iron or brass ferules, so necessary to prevent -splitting. You may buy your first few simple tools -handled, but after you have these you can turn as many -handles as you like, and you can buy ferules of all sizes at -any regular tool-shop.</p> - -<p><span class="pagenum"><a name="Page_116" id="Page_116">[116]</a></span></p> - -<p>I may as well tell you that in a great many country -towns you will be unable to obtain turning tools except -gouges and chisels, so that when you buy your lathe in -London, as you will find the best plan (or in Manchester, -Birmingham, or other manufacturing town, if nearer to -you), you must lay in a little stock of tools at the same -time, and take future opportunities of getting more. In -regular tool-shops you will have them laid before you by -dozens of every conceivable shape and size, so that your -great difficulty would be what to pick out if it were not for -some such directions as I am now about to give you.</p> - -<p>First, you will want gouges and chisels. Begin with two -sizes of each—one of half an inch, the other of 1 inch in -width. These are to be mounted in long handles.</p> - -<p>Now, with these alone you can do all the plain work in -soft wood which does not require to be hollowed out, tool-handles, -chair-legs, legs of towel-horses, round rulers, and -all sorts of things, and to a certain extent you can turn out -the insides of wooden chucks, bowls, and boxes, but not -very easily with these alone. Hence you must add some -of those shown in Fig. 42. These I shall endeavour to -assort as follows:—</p> - -<p>A to F are for hollowing out hard woods; G and H are -hook-tools (very difficult to use) for hollowing out soft -wood boxes and bowls.</p> - -<p><span class="pagenum"><a name="Page_117" id="Page_117">[117]</a></span></p> - -<div class="figcenter" style="width: 600px;" id="fig42"> -<img src="images/figure42.jpg" width="600" height="400" alt="" /> -<p class="caption">Fig. 42.</p> -</div> - -<p><span class="pagenum"><a name="Page_118" id="Page_118">[118]</a></span></p> - -<p>I and K show the edge and side of a parting tool for -cutting off the ends of cylindrical pieces, separating the -turned from the unturned parts, and for all similar work. -[A tenon-saw held still against a piece revolving in the -lathe will often serve to cut it in two, but parting tools -must also be had, and two are better than one, as a thick -one should be kept for common woods, and a thin one -for ivory and precious materials; sometimes one with a -<i>notched</i> edge is used for cutting off soft wood.]</p> - -<p>L to O are for turning iron and steel. The first is a -<i>graver</i>, of which all sizes are made; one of a quarter inch -width on either face is large enough. It is a square bar of -steel ground off cornerwise so as to form a lozenge-shaped -face. This is an essential tool for iron, and will do all -sorts of work.</p> - -<p>M is a hook or heel tool, made sometimes with a flat -edge and sometimes with a rounded one, the latter being -most useful. It is a very powerful tool, much used by -some, especially for heavy work—I don’t think you need -get one at present. If I am able to teach you to use a -graver it will do almost as much work, and is a neater tool. -If you use a tool of the nature of heel-tools at all, I think, -on the whole, the nail-head tool, N, either round or square, is -the best. It is at all events handy for roughing down work, -and when it is reduced nearly to the size required, and is -partly smoothed, the graver will finish it.</p> - -<p>O is an inside tool for hollowing out iron. There are<span class="pagenum"><a name="Page_119" id="Page_119">[119]</a></span> -different shapes of this used, each turner giving the preference -to some particular pattern to which he has habituated -himself. None of these tools for metal have sharp edges—at -least they would not appear so to an ordinary observer. -The angle of the edge is 60° to 80°, or even 90°, which is, as -you know, a right angle, and is that most generally used -for the cutting edges of tools intended for brass, as U, V, -W, of which V is a most useful pattern. Those for hard -wood have edges a little more keen, but after all they -scrape rather than cut; the only tools for wood with keen -edges being the gouge and chisel.</p> - -<p>P are callipers for measuring the <i>outside</i> of work of all -kinds. Q and R are the same, arranged for in and outside -work. The first is an ordinary pair closed until the ends -have crossed, which they will all do; but if the inside of -hollow work to be gauged is small, they will not enter it. -In this case none are so generally useful as the in-and-out -callipers, R, for when accurately made (and if not you can -easily correct them with a small file), the one end will -measure the external diameter of work, and at the same -time the other end will be found to have its points separated -to such a distance, that if you were to turn a box or chuck -to this inside measure, the cylinder first turned will exactly -fit it. Thus if you turn a box-cover, and take the size of -it with the straight end of the callipers, and then turn -down the rim of the box until it is just the size indicated<span class="pagenum"><a name="Page_120" id="Page_120">[120]</a></span> -by the curved ends, the one will exactly fit the other. In -turning a piston to fit the cylinder of an engine, you would -work with this useful tool.</p> - -<p>S is the turner’s square. The blade slides stiffly and accurately -in a slot in the brass, being kept by a spring at one side -from working loose. This square is used to gauge the depth -of boxes and other works which are to be turned to an exact -size, and it also serves to test the squareness of many kinds -of work. Suppose, for instance, you had turned a box, you -would put the blade of this tool against the bottom and -press upon it till the brass rested across the rim, touching -it in two opposite places. Now possibly the inside may be -smaller at the bottom than at the top. Test it by bringing -the steel blade edgewise against it. You will see whether -the brass still touches in two places across the mouth of -the box. The squareness of the outside with the top or -bottom can be tested in a similar way. We shall have -occasion to recur to this when we come to boring and fitting -engine cylinders.</p> - -<p>S² is another small square, which is often serviceable -where the carpenter’s square cannot be used. If you intend -to make models, you will want both of these; at the same -time, it is quite possible to make the latter of iron, or even -thick tin, if you have the former, as an accurate guide to -work by.</p> - -<p>T represents a pair of spring-compasses or callipers.<span class="pagenum"><a name="Page_121" id="Page_121">[121]</a></span> -They are used to set off distances, and have the advantage -of not being liable to shift their position when once they -are set to any required width. You will require a pair of -compasses of some sort, and if not already provided, these -are the best you can have.</p> - -<p>There are many other tools, which, though not absolutely -turning tools, are more or less used in connection with the -lathe, but these need not now be further alluded to, and I -shall go on to describe as clearly as possible the method of -working at the lathe with hand-tools, commencing with the -operation of turning soft wood with the gouge and chisel; -but I must first give a short chapter upon the nature of -woods used.</p> - -<div class="figcenter" style="width: 250px;"> -<img src="images/footer6.jpg" width="250" height="125" alt="" /> -</div> - -<hr /> - -<p><span class="pagenum"><a name="Page_122" id="Page_122">[122]</a></span></p> - -<div class="figcenter" style="width: 500px;"> -<img src="images/header5.jpg" width="500" height="110" alt="" /> -</div> - -<h2 id="CHAPTER_VIII"><span class="smcap">Chapter VIII.</span></h2> - -<div> -<img class="dropcap" src="images/dropcap-a.jpg" width="100" height="120" alt="" /> -</div> - -<p class="dropcap">As different materials require somewhat different -management, and even in the matter of wood -alone this rule holds good, it may be as well -to have some idea of what is meant by <i>hard</i> -and <i>soft</i> wood.</p> - -<p>The young mechanic has most likely hitherto considered -all wood under one head; but there is a vast difference, -nevertheless, in the internal structure, even of such kinds -as grow in England; and the woods of foreign countries -differ again from these, some being of such close texture -that it is almost impossible to work them with ordinary -tools, and some (such as the palm) being little else than -gigantic ferns, and in structure like that much-dreaded -implement of flagellation—the schoolmaster’s cane.</p> - -<p>In England the hardest wood found is that of the box-tree, -the chief place of which is in Surrey, at Box Hill; it<span class="pagenum"><a name="Page_123" id="Page_123">[123]</a></span> -is, nevertheless, found scattered here and there in all parts -of the country, but not generally of a size greater than 3 -inches in diameter. It is of very slow growth, and our own -country would not nearly satisfy the demand made for it -by various trades. Hence a large quantity of box, of larger -growth, and generally of harder and better quality, is imported -every year from Turkey, to be used in the construction -of blocks for engravers, who alone require many -tons weight annually, and for carpenters’ rules, mallets, -turned boxes, and tool-handles; to which I may add the -important item of peg-tops. I fear some of my readers -may think I should have placed these first on the list! -Opinions, however, I imagine, differ in this particular, as -in most others, and upon all subjects.</p> - -<p>The grain of boxwood is so close and even that it is one -of the most valuable turning materials we possess. It -takes excellent screw-threads, provided they are not too -fine; is a very general material for boxes of all kinds, and -also for chucks, although there is really no reason why it -should be wasted in so applying it, when other woods of -less value make such efficient substitutes. Probably its -use for this purpose arose from the facility with which a -screw can be cut in it to fit that on the mandrel, and that -it is so hard as not to allow the collar beyond the screw to -make much impression upon it. In consequence, when it -is well fitted, such a chuck can be screwed on many times<span class="pagenum"><a name="Page_124" id="Page_124">[124]</a></span> -exactly to the same point, and will continue to run true. -But I myself have found that if the mandrel-screw is not -very coarse, the threads cut in the inside of the chuck are -apt to break off.</p> - -<p>Somewhat similar in texture, though by no means -generally used, is the wood of the <span class="smcap">Elder</span>, which is quite -different, be it observed, from the <span class="smcap">Alder</span>, although I often -hear the names confounded together. The wood I allude -to is that of the tree which bears umbels of sweet, white -blossoms, which give place to those jet-black berries we -find upon them late in summer, and which are made into -elder-wine, for home consumption at Christmas, when, no -doubt, most of my readers have drunk it, hot and spicy and -sugary, to keep out the wintry cold. From the same tree -are commonly made those harmless engines of mimic warfare—pop-guns!</p> - -<p>If it were not for the presence of the pith, which is in -fact the very quality which makes it valuable to boys for the -latter purpose, this wood would certainly have been eagerly -seized upon by turners. Even with this defect, it is used -instead of box for the inferior kinds of carpenter’s rules -and other purposes, and the larger pieces will make very -good chucks, if a little care is exercised to prevent splitting -them. It is indeed a wood that might be far more extensively -used in this way than it is.</p> - -<p>The <span class="smcap">Yew</span>, perhaps, should come next in order, for this too<span class="pagenum"><a name="Page_125" id="Page_125">[125]</a></span> -is very close-grained and very beautiful, and when highly -polished it will bear comparison with many foreign woods -which we import at a high price; it is, however, brittle and -apt to splinter.</p> - -<p><span class="smcap">Walnut</span> varies considerably in quality, some being -harder and richer in grain than others. This wood, however, -is not to be classed among those which are properly -speaking <i>hard</i>, as it can be cut with ease, and can only be -planed and worked as deal would be, viz., <i>with the grain</i>; -whereas the hard woods work with <i>almost</i> equal facility in -either direction. This indeed in a great measure constitutes -the difference between soft and hard woods, in the -turner’s sense of the words. If you were to hold a chisel -flat on the rest, so as to let it scrape a cylinder of wood as -it revolved in the lathe, you would find in some cases that -it would tear out the fibres in shreds—<i>these are soft woods</i>. -In other cases it would leave the surface rough but otherwise -tolerably even, and with some it would leave the same -fairly turned.</p> - -<p>I cannot call to mind any English wood but box that -can be turned by a chisel held so as to scrape it, but the -greater number of foreign woods are always turned in this -manner, being hard and close in the grain.</p> - -<p><span class="smcap">Birch.</span>—Oh, once-dreaded tree! birch! with its long, -swaying, switchy boughs, drooping as in sorrow at the -mean uses to which it was applied! It is nevertheless a very<span class="pagenum"><a name="Page_126" id="Page_126">[126]</a></span> -useful tree, and the young mechanic can take full revenge -upon it by cutting, and chipping, and turning it into all -sorts of useful articles. It is, however, now more generally -used in cabinetmaking, for wardrobes, bedsteads, chests of -drawers, and such like, as it looks very neat when planed -and varnished. Perhaps, as a wood for the exercise of the -turner’s art, it must give place to</p> - -<p><span class="smcap">Beech</span>, which is a common and excellent material for -the essays of beginners, who can turn tool handles especially -from the small trimmed billets of it which are kept -by the chairmakers, and which can generally be bought for -a trifling sum in any town, and in many villages. If not, -the wheelwright may be applied to for a supply, as he uses -it rather extensively for the felloes of his wheels. It is -peculiarly liable to the attacks of the little worm, weevil or -maggot, who drills such innumerable and such beautifully -round holes in furniture that stands long unused.</p> - -<p>Beech is often used for the screws of carpenters’ benches, -as it takes very well a thread of such size as is required for -that purpose. It will also, for the same reason, answer -very well for chucks, for which it has the recommendation -of cheapness and toughness.</p> - -<p><span class="smcap">Ash</span> seems to come next upon the list. It is probably -the most useful of all English woods, and where toughness, -pliability, with moderate hardness, are valuable qualities, -no English wood can exceed it. For frames of carts and<span class="pagenum"><a name="Page_127" id="Page_127">[127]</a></span> -carriages, shafts, agricultural implements, wheelbarrows, -and smaller articles of husbandry, it is precisely what is -needed, and in the workshop of the turner it is equally -valuable. Tool-handles of ash are very durable, and hold -the tool with great firmness, owing to the natural elasticity -of the material. It may be stained and polished, and is -then, for real <i>work</i>, preferable to the more costly hard -woods of which handles are very generally made for the -workshops of rich amateur mechanics.</p> - -<p><span class="smcap">Oak</span> is little used for turning, the grain being too coarse. -The young mechanic need never make use of it for this -purpose, and the same may be said of the elm.</p> - -<p><span class="smcap">Elm</span> is, nevertheless, used by turners for the wooden -buckets of pumps, and is a generally useful wood. Bulk -for bulk, it is lighter than beech, and it makes a good -material, it is said, for lathe beds, though beech is more -frequently used. It will answer for chucks, as indeed -most woods will that can be cut into screws; it is very -tough.</p> - -<p><span class="smcap">Evergreen Oak</span>, or <span class="smcap">Holm Oak</span>, as it is called, is very -different to the forest tree, and might be classed among -shrubs. When dry, it is by no means a bad wood to turn, -and will take a good screw thread, and make excellent -chucks.</p> - -<p><span class="smcap">Acacia</span> is an excellent wood. It is of a yellowish brown -colour, tolerably hard, and will take a good polish. It is<span class="pagenum"><a name="Page_128" id="Page_128">[128]</a></span> -most certainly to be set down among the woods valuable to -the turner.</p> - -<p><span class="smcap">Sycamore</span> is white, very soft until old, when it becomes -much harder. This is also a turner’s wood, and used extensively -for wooden bowls, backs of brushes, turned boxes, -and what is generally called “turnery.” A little of this -will be useful to the young mechanic. It will make excellent -bread platters, stands for hot water jugs, and such -like.</p> - -<p><span class="smcap">Holly.</span>—The Christmas garland, with its red berries -decorating even the poorest homes in midwinter, is a tree -well worth the attention of the young mechanic. It is his -substitute for the more precious material ivory, and from -it he will turn the white draught or chess men, boxes, and -many small articles. But it is necessary that this material -should be perfectly dry, and to get it in perfection, carefully -preserved to insure its whiteness, it will be generally -necessary to procure it ready for the lathe at some lathemaker’s, -or at first-class cabinetmakers’. If cut green, it -requires long seasoning, during which it shrinks considerably. -In fact, it takes some years entirely to rid it of the -great quantity of moisture which it contains. It is well -worth procuring, nevertheless, for it is nearly as white and -free from grain as ivory.</p> - -<p>Many of the fruit-trees of our orchards and gardens -supply good material to the turner. <span class="smcap">Apple</span>, <span class="smcap">Pear</span>,<span class="pagenum"><a name="Page_129" id="Page_129">[129]</a></span> -<span class="smcap">Cherry</span>, <span class="smcap">Plum</span>, and some others, are all more or less -useful. The grain of the first is rather dark, the fibres -often twisted. It looks well when polished.</p> - -<p><span class="smcap">Pear</span> has a very fine, even grain, and is largely used -for making the curved templates (or patterns of curves for -architects and engineers); it will make good boxes, and is -fairly serviceable to the turner. Its colour is light brown, -but darkens by exposure.</p> - -<p>The <span class="smcap">Plum</span> has a wood veined very like that of the elm, -but is a finer and better wood for the lathe. This is the -<i>wild</i> plum, and not the grafted fruit-tree of our gardens, -which is not nearly so good. The wild plum is excellent -for small boxes, and looks well when nicely turned and -polished.</p> - -<p><span class="smcap">Cherry</span> is a very excellent wood, and naughty, fast boys, -who take to smoking, like young Americans, when they -ought to be filling their young brains with knowledge -instead of narcotics, know very well that it is made into -pipes and stems of pipes. Happily this is not its only -use, for it is fit for many other purposes; and for light, -elegant furniture, it is scarcely to be equalled. Dipped in -lime-water, it darkens, and by doing this here and there, a -beautiful mottled appearance is given to it. It takes an -excellent polish, and should be among the stores of the -young mechanic.</p> - -<p>We now come to another soft, white wood. The <span class="smcap">Lime</span>,<span class="pagenum"><a name="Page_130" id="Page_130">[130]</a></span> -which, as it is more even in grain, more easily cut in -any direction than most woods, is greatly used by carvers -and pattern-makers (<i>i.e.</i>, those who make wooden patterns -of wheels, or lathes, or machinery, which are to be cast in -metal). [The pattern is pressed into damp sand, and then -removed, and the melted metal is then poured into the impression -thus made. If the sand is too wet, the process -will not only fail, but the hot metal will be scattered on all -sides, inflicting dreadful burns and injuries; but with care, -the young amateur may make castings in tin or lead, as will -be explained by and by.] Even with a penknife alone, -very pretty ornaments may be carved from the wood of the -lime, and also from that which follows.</p> - -<p><span class="smcap">Willow.</span>—This is even softer than the last, and will -plane into long, thin shavings, which are made into hats. -(Once on a time I should have said “<i>and bonnets</i>,” but in -these days no one would recognise such articles. They are -fast fading out of existence; but I think quite as much -sound sense used to be found under them as is now found -under the very inefficient substitutes worn by ladies of the -present day.) This wood will, of course, turn very easily, -but requires very keen tools. In fact, <i>sharp</i> gouges and -chisels are invariably necessary for soft wood turning. -Get some dry willow by all means, if you can.</p> - -<p>The last wood of English growth which the young -mechanic is likely to meet with is the thorn. This grows<span class="pagenum"><a name="Page_131" id="Page_131">[131]</a></span> -to a tolerably large size, and is hard, close-grained, white, -and altogether a good and serviceable wood. It will -make capital chucks, taking a clean screw-thread, is easily -procured, and is therefore strongly recommended to the -notice of the young mechanic. The woods above named, -except box, are all to be considered <i>soft</i> woods, and will -work with gouge and chisel; but box, thorn, elder, and one -or two of the more close-grained, will turn pretty well, and -can be smoothly hollowed out, with hard wood tools held -horizontally upon the rest.</p> - -<h3>HARD WOODS.</h3> - -<p>All those woods, properly called <i>hard</i>, including the best -box, are of foreign growth, mostly coming from the Tropics. -I do not know why they should be so much harder than -those of temperate climes, but so it is. There are, however, -woods in New Zealand, of which the temperature is similar -to that of our own country, which are also exceedingly hard -and difficult to work. A very large number of foreign -woods are yearly brought to England in logs or billets or -planks, some of very large size, and all of great weight. -They are mostly liable to one defect, viz., rottenness of the -core or heart, which limits the size of the pieces which can -be cut from them. They can all be procured from the -London lathe and tool shops, and there are also dealers in -these woods (Jacques of Covent Garden, Mundy & Berrie<span class="pagenum"><a name="Page_132" id="Page_132">[132]</a></span> -of Bunhill Row, and some others). It is almost impossible -to procure them in the country, but rosewood, ebony, kingwood, -&c., may be sometimes had in such small pieces as -the young mechanic may require, at the cabinetmakers’. -Among the most useful are—</p> - -<p><span class="smcap">Ebony</span>, of which there are two or three kinds, some -harder and more close-grained and blacker than others, -and one which is called green ebony, which is like lignum-vitæ -(an English wood, but which grows to a larger size -abroad; indeed, many so called English woods are not -really so, but have been brought from other countries to be -grown here). The general colour is green, but the veins -are rather darker. Bowls and skittle-balls are made of -it. It is not, however, of the same general use as the -black ebony, which is very largely used both for cabinet-work -and turning.</p> - -<p><span class="smcap">Black Ebony</span> is very close and hard, and, of course, proportionately -heavy. It splits readily, but when chopped, -the chips come off more like charcoal, showing no consistency. -This is the kind imported from the Indies, and -especially from Madagascar and Mauritius, and is the best -for all kinds of turned work. Portugal affords another -kind, which bears the same name, but is more brown than -black, and softer, less compact in grain, and generally -of less value. Ebony will bear eccentric work, and all -kinds of beautiful carving and ornamentation in the lathe.</p> - -<p><span class="pagenum"><a name="Page_133" id="Page_133">[133]</a></span></p> - -<p><span class="smcap">Rose-wood</span> is very commonly used for furniture and -turned work. It is a rich red wood, grained with black. It -is not <i>very</i> hard, less so than ebony, and has more evident -grain or fibre. It turns well, and some pieces are very -handsome.</p> - -<p><span class="smcap">African Black-wood</span> is in appearance similar to ebony, -but it is even more close and compact, and is the most valuable -of all to the ornamental turner. When this or ebony is -set off by being inlaid with ivory, or even holly, it is very -lovely in its intense and brilliant blackness. Either this -or ebony is used for black pieces for the chessboard or -draughtboard, though stained boxwood, being less costly, -is sometimes made to take its place.</p> - -<p><span class="smcap">African Cam-wood</span> is a very beautiful material when -first cut. Its rich red tint is diversified with the most -brilliant yellow streaks. Unfortunately, however, these -are not lasting. Exposed to the air, they gradually become -darker, until they become red like the rest of the wood. -This material, however, has a fine, close grain, is a genuine -<i>hard</i> wood, and of general use to the turner for ornamental -articles of various kinds.</p> - -<p><span class="smcap">Tulip-wood</span> is not very hard. Cut across the log, the -appearance is fine, owing to the rings of growth being -wavy and irregular, in dark and light red alternations, that -reminds one of the flower after which it is called. This -tree, indeed, which grows to a large size, bears flowers<span class="pagenum"><a name="Page_134" id="Page_134">[134]</a></span> -similar to those of our gardens imported from Holland, -which grow upon short perpendicular stems. The centre or -core of tulip-wood is generally rotten. It sucks up a good -deal of polish before the grain shows out brightly and -strongly, from being less hard and more fibrous than many -others named above.</p> - -<p><span class="smcap">Partridge-wood</span> is a nice, hard, and very pretty wood, -rather dark or gray. The fibres seem to run both ways, -giving a mottled appearance when turned.</p> - -<p><span class="smcap">Coral-wood</span> is bright red, hard, and close in grain, well -suited for red chessmen, where that colour is preferred to -black. It looks very handsome in the midst of other -coloured specimens; otherwise, like all material of one -tint and free from veined lines, there is too much uniformity -of appearance to make it pleasing to the eye of one who is -gifted with appreciation of colour.</p> - -<p>It is not necessary for me to go in order through a long -list of foreign woods. The very young mechanic, unless -living in London, will seldom meet with many of them; -and a very good selection for the advanced turner will be -composed of the following:—</p> - -<p><span class="smcap">Black Ebony.</span></p> - -<p><span class="smcap">Cocoa</span> or <span class="smcap">Cocus</span>, which is not the cocoa-nut tree, this -being a palm, the wood of which is stringy like a fern or a -cane; whereas, cocoa or cocus is firm, hard, and excellent.</p> - -<p><span class="smcap">Black-wood</span>, which cuts finely with tools for eccentric work.</p> - -<p><span class="pagenum"><a name="Page_135" id="Page_135">[135]</a></span></p> - -<p><span class="smcap">King-wood</span>, a good and useful wood, something akin in -appearance to rosewood.</p> - -<p><span class="smcap">Satin-wood</span>, pale yellow grain, like watered silk, turns -very well, but is by no means hard; there is also a red -satinwood.</p> - -<p><span class="smcap">Rose-wood</span>, already described; it loses colour after -exposure, and is most beautiful newly cut.</p> - -<p>If the above are added to the most useful of the English -woods described above, it will scarcely be worth while to -add to them except as <i>specimens</i>. It is, however, very -interesting to collect and arrange these, and it is an employment -well worthy of the attention of the young -mechanic. Thin slices cut across the grain, and sometimes, -or in addition, slices cut with the grain, should be -arranged in order after being trimmed to shape (round, -square, or triangular, or even six-sided). They should be -very carefully polished to bring up the grain, and labelled -with the common and Latin (or botanical) name. The -country from which procured, with short notes relative to -the size and general growth of the tree, should be added. -This will compel inquiry, and a great deal of information -will be thus gained and stored up. A similar collection of -English woods may be made, and, of course, with much -greater ease.</p> - -<p>It will be observed that I have said nothing of the pines, -deal, and larch. They are extensively turned in the lathe,<span class="pagenum"><a name="Page_136" id="Page_136">[136]</a></span> -the greater part of the common painted furniture being -made therefrom; but deal is, nevertheless, not a turning -wood. It splits easily, has an open grain, with fibres -loosely connected, and although it can be cut into mouldings -with sharp chisels and gouges, it generally needs a -little rubbing with Dutch rush, fish-skin, or glass-paper; -after which, a handful of its own shavings held against it -as it revolves rapidly in the lathe, is the best polisher. Of -course, however, it may be varnished, and of late years it -has become fashionable, when thus finished, for bedroom -furniture. It is, however, in this case generally improved -and embellished, by having thin strips of coloured woods -inlaid in its surface. It is useless for <i>hollow</i> work; and -wood that cannot be hollowed out satisfactorily, is not to be -classed among those suitable for the turner.</p> - -<p>Whenever you have time to spare, and are not inclined -to turn, yet feel disposed to wander into your workshop, it -is a good plan to trim and prepare pieces of wood for the -lathe. You need a chopping-block, which is the end of a -stick of timber sawn evenly across, and stood up in some -out-of-the-way corner where chips will not be much in the -way, and a light axe or adze, which latter is said to be the -best. It is called the bassoohlah or Indian adze, but I -never had one, nor ever saw it mentioned, except in one -very excellent book by the late Charles Holtzappffel of -London, who, indeed, keeps these tools. But a light axe is<span class="pagenum"><a name="Page_137" id="Page_137">[137]</a></span> -easily obtained, and will do very well. Take care to saw -the pieces off truly square—I mean straight across the log, -and not slanting either way. Cut some from your evergreen -oak, or beech, or elm, for chucks, remembering to -have length for the mandrel screw, beyond what you will -probably need for hollowing out, to take the pieces to be -turned. Cut some longer than others, and from larger or -smaller pieces; from 2-inch diameter to 4, which is a useful -general size. But your lathe of 5-inch centre will take -chucks or work of nearly 10 inches, so you can cut some -few pieces rather larger. Probably, your only work of 6 to -9 inches diameter will be an occasional bread-platter, or a -stand of some sort; your general work will be much less. -Besides chucks, of which the number is in time very great, -you will be constantly wanting tool-handles. Cut some -for these, and placing one end on the chopping-block, trim -them to something like the required size, but a good deal -larger round than you think necessary, because you will -find that the size will deceive you frequently.</p> - -<div class="figcenter" style="width: 500px;" id="fig43"> -<img src="images/figure43.jpg" width="500" height="500" alt="" /> -<p class="caption">Fig. 43.</p> -</div> - -<p>For finally trimming up short pieces, a peculiar knife is -used by the lathe and tool makers; and when you can spare -the money you should get one, as you will find it easy to -use, and it will save you many a cut from the axe. In -fact, I never advise <i>very</i> young mechanics to make use of -the latter tool. It requires practice, strength, and a good -deal of skill to use it well; and nothing is more easy than<span class="pagenum"><a name="Page_138" id="Page_138">[138]</a></span> -to lop off the end of a finger or thumb, and, unfortunately, -nothing is more difficult than to repair the damage. The -paring-knife for short thick pieces mentioned above, is -made like D, Fig. 43. It consists of a long and curved -handle, turned up at one end to fit under a staple, E, with a -cross piece of wood for the hand at the other end, and a broad -strong blade with one bevel in the middle—(by one bevel I -mean, that the edge is not like that of an axe, but like that<span class="pagenum"><a name="Page_139" id="Page_139">[139]</a></span> -of a carpenter’s chisel, the bevel or sloping part being outside). -C is the piece of wood to be pared, A the bottom -board or platform, B a block fastened to it, and made on a -slope to prevent the tendency of the wood to slip away from -the knife. The whole of this may be screwed down to the -bench, or to a heavy stool when in use. The hook and -ferule should not be made so large and loose as in the -drawing, and a better joint is that of an ordinary hinge. -If made loosely, the blade twists about too much from side -to side, escaping from the wood. There is no danger to the -fingers from this useful tool, which the young mechanic -should add to his workshop as soon as he can.</p> - -<p>Another useful and easily-constructed apparatus for the -preparation of long pieces is the shave-stool, used by -coopers and chairmakers to hold the pieces securely while -they are being shaped by the double-handled shave or -drawknife, as it is often called, a tool omitted from our -list, but very useful all the same. This is sketched at B, -Fig. 43. It is often very roughly made, the chief necessity -being that it shall be strong. It answers also for a sawing-stool. -Upon the stool or bench, A, is fixed a sloping block, -B. A swinging frame, C, is hinged or pivoted at D, so -that if the lower part is pushed back from left to right, -the upper cross-bar, E, will come forward and almost touch -the highest part of the sloping block, B, so that any piece -of wood, such as F, will thereby be pinched and held tightly<span class="pagenum"><a name="Page_140" id="Page_140">[140]</a></span> -between the rail, E, and the block. The workman sits -astride of the stool at A, facing the block, and his feet are -placed on the bar C. When he wishes to hold the wood -which is to be shaved by the drawknife C, he presses <i>from</i> -him with his feet the lower part of the frame, and he can -instantly loosen the wood by drawing his feet towards -him. The movement is made in a moment, and the wood -shifted round as required, and alternately turned about and -held tight, while the drawknife is used almost ceaselessly. -A very few minutes generally suffices thus to pare down -a rough piece for the lathe. The cross-bar, E, should be -tolerably strong, and is better if not rounded very nicely, -as the edges help to hold the wood. The latter is sure not -to slip away, because the pull of the drawknife tends to -draw it up higher on the slope of the block, which pulls it -into a still narrower opening. Nothing can exceed the -ease with which this appliance is used, and the rapidity -with which the required operation can be carried on. No -wood-turner’s shop should be without one.</p> - -<h3>ORDER AND ARRANGEMENT OF TOOLS.</h3> - -<div class="figcenter" style="width: 500px;" id="fig44"> -<img src="images/figure44.jpg" width="500" height="375" alt="" /> -<p class="caption">Fig. 44.</p> -</div> - -<p>I must say a word or two as to neatness and order, -especially in the arrangement of tools and appliances for -the lathe. Whether you have a dozen tools or a hundred, -always put them in the <i>same place</i>, so that any particular -article can be found instantly, no time being wasted<span class="pagenum"><a name="Page_141" id="Page_141">[141]</a></span> -hunting up and down, or examining a long row of tools for -the one required at that particular time. Turning tools, -moreover, should be kept distinct from those used for -carpentry, and in a special rack by themselves. The best -tool-rack, I think, which can be made, is one like Fig. 44. -This may be made of deal, but the pieces between the holes -are thus liable to get split off, and beech or ash is therefore -preferable. The whole frame is made to be screwed to the -wall; or, if the latter is damp, the frame should be first -screwed to a board covered with baize, and this, in turn, -fixed to the wall. Thus arranged, it will have a very neat<span class="pagenum"><a name="Page_142" id="Page_142">[142]</a></span> -appearance, and the tools being kept dry, will remain -generally free from rust. They should, nevertheless, be -carefully looked over once a week and wiped, when those -requiring to be ground should be subjected to that operation, -and thus be ready for future use when required. They -are bad workmen who allow blunt or damaged tools to accumulate, -instead of at once setting them in order. The horizontal -bars are bored with holes by means of a centrebit. -The holes must be arranged as to size by the measurement -of the <i>ferules</i> of the tool handles, some being larger and -some smaller, so that when the tool is placed in any hole, -the handle will drop in to the depth of the ferule and fit. -Thus the tools will all stand upright, instead of leaning -from one side or the other. After the holes are made, a -piece is cut out (see fig. B) at the front edge, because the -blades of some tools are wider than the ferules, and, in -addition, if this were not done, the different tool-rails must -be as far apart as the whole length of the tool (handle and -all included), to allow of the latter being lifted sufficiently -high to drop into the holes.</p> - -<p>The strips for the holes should be about 2 inches wide, -the lower one, for the larger chisels and gouges, rather -wider than the upper ones. Sometimes these tool-racks -are fitted up inside a cabinet, whose doors have similar -racks; thus all can be shut in out of the reach of dust and -dirt. Holtzappffel, the great lathemaker of London, fits<span class="pagenum"><a name="Page_143" id="Page_143">[143]</a></span> -up such cabinets complete in oak or mahogany, all the -tools being handled in hard wood and turned to one -pattern. The cost, however, £5 and upwards, renders -such less desirable to the young mechanic, who can rig up -a common tool-rack, which will serve his purpose equally -well. It is also far more satisfactory, in looking round -your workshop, to feel that you have at all events been as -little extravagant as possible, for amateurs get no return -for outlay as tradesmen do.</p> - -<div class="figcenter" style="width: 250px;"> -<img src="images/footer2.jpg" width="250" height="125" alt="" /> -</div> - -<hr /> - -<p><span class="pagenum"><a name="Page_144" id="Page_144">[144]</a></span></p> - -<div class="figcenter" style="width: 500px;"> -<img src="images/header2.jpg" width="500" height="110" alt="" /> -</div> - -<h2 id="CHAPTER_IX"><span class="smcap">Chapter IX.</span></h2> - -<div> -<img class="dropcap" src="images/dropcap-t.jpg" width="100" height="120" alt="" /> -</div> - -<p class="dropcap">There is no operation in which the young -mechanic is so much at fault as in that of -grinding and setting in order the various tools -he has to use. Nevertheless he will never become -either an independent workman or a good one, if he -has to depend upon others for this necessary labour.</p> - -<p>No doubt, to sharpen a tool which is in very bad order -is a tedious and tiresome job; but it is not so wearisome -an affair to keep tools in condition for work, after they -have been once thoroughly sharpened by one who understands -how to do it. Never, therefore, use a blunt tool, but -at once go to the hone or grindstone with it, and put it in -first-rate order. Time thus employed is never wasted, but -rather saved; and the result will appear invariably in the -work which you are engaged upon. You must, in the first -place, understand precisely what it is you have to do; and<span class="pagenum"><a name="Page_145" id="Page_145">[145]</a></span> -although the following details may be by some considered -more adapted for advanced students than for young mechanics, -a little attention to the explanations will render the -matter clear to any boy of age and intelligence to take in -hand, with reasonable prospect of success, the tools of the -carpenter, turner, and fitter. I can only say, that boys of -this generation are wonderfully well off in having these -things explained to them. Twenty years ago young mechanics -had to grope along in the dark, ignorant to a great -extent of the <i>principles</i> of work, and almost equally uninstructed -in the practical part of it.</p> - -<p>In Fig. 45 are represented similar angles to those already -explained to you, and you will quickly understand how useful -is a little knowledge of the elements of mathematics. -Suppose A to be a tool, the angle of the point is a right -angle, or 90°. B is another of 60° at the point, and I have -drawn a line across to show you that the three sides of this -figure (called a triangle) are equal. So remember that if -you want an angle of 60°, you have only to draw a triangle -of three equal sides, and each of these angles will be 60°. -Again, I may as well remind you that three times 60° equals -180°, which is equal to <i>two right angles</i>, so we find here that -the three angles of an equal-sided triangle equal two right -angles, and even if the sides are not equal, the same thing -is true. For instance, look at the first tool, across which I -have also drawn a line to make a triangle. The point we<span class="pagenum"><a name="Page_146" id="Page_146">[146]</a></span> -know is 90°, and if the sides, <i>a b</i>, are equal (although the -third line is <i>not</i> equal to either), the two small angles are -each 45°, <i>i.e.</i>, 90° between them, so the three angles again -equal 180°.</p> - -<div class="figcenter" style="width: 500px;" id="fig45"> -<img src="images/figure45.jpg" width="500" height="650" alt="" /> -<p class="caption">Fig. 45.</p> -</div> - -<p><span class="pagenum"><a name="Page_147" id="Page_147">[147]</a></span></p> - -<p>The third tool (which we may suppose a turner’s chisel -held <i>edgewise</i>) is shown to have an angle of 30°, and I have -added one more which has an angle of 45°. Now all tools, -if <i>well</i> ground, are ground to a certain known angle, according -to the material which they are intended to cut. Tools -intended to cut soft woods, like deal, are ground to an angle -of 20° to 30°, like the chisel seen edgewise. I shall have a -word to say presently as to the direction in which such -tools are to be held, in order to make them cut as well as -possible. A tool for hard wood is given next at E. The -angle is now at least 40°, and it ranges up to 80°, giving a -stronger, thicker edge, but not so keen a one. We have, -therefore, more of a scraping tool than a cutting one,—at -least, in the way it is usually held. Then we come to the -tools with which iron is turned and steel also. Fig. F is -one of these, and the usual angle is 60°, and thence it -ranges to 90°. Thus you see, advancing from soft wood -tools to those for hard wood, and thence to a substance still -harder, we have increased the angle of the edge, beginning -at 30° and ending with 80° or 90°. But now we come to a -material which is harder than wood and not so hard as -iron, yet we use tools with an angle of 90°, which is still -greater, and 70° is the least angle ever used for this metal.</p> - -<p>Experience only has taught the proper angle for tools, -and it is found, that if brass and gun-metal are turned with -tools of a less angle than 70°, they only catch into the<span class="pagenum"><a name="Page_148" id="Page_148">[148]</a></span> -material, and do not work at all satisfactorily. You can, -however, <i>scrape</i> brass, as a finish, with the thin edge of a -common chisel; but then the tool is held so as to scrape -very lightly and polish; and its edge will not remain many -minutes, unless the maker (intending it to be so used) has -made it much harder than he would make it for soft wood -cutting.</p> - -<p>If you buy your tools at any <i>good</i> shop, you will find that -they are already ground to nearly the angles named, and -when you re-grind them, you must endeavour to keep them -to the same. The <i>bevel</i>, as it is called, of many tools need -not be ground at all, as they may be sharpened solely by -rubbing the upper face on a hone, or grinding it, holding it -so that the stone shall act equally on all parts of it. If, -however, the tool should become notched, you must grind -the bevel of it, and then you must try and keep the -intended angle. One tool, however, or rather one pair of -tools, viz., turning-gouges and chisels, are very seldom -ground with a sufficiently long bevel when they first come -from the maker. The usual shape of the edge is like G, -whereas the angle should be much less, as seen at H. This -you must correct when you first grind the tools for use, and -keep the same long bevel and small angle of edge continually -afterwards, for you will never make good work on soft -wood if your chisels and gouges are ground with too short -a bevel.</p> - -<p><span class="pagenum"><a name="Page_149" id="Page_149">[149]</a></span></p> - -<p>I must also guard you against another common error, -which, however, is very difficult to avoid at first, and only -long practice will enable you entirely to overcome it. I, is -the chisel (held edgewise as before) ground as it ought to -be; K is the same tool ground as it generally is by young -hands, or, even if it is correctly formed at the grindstone, -one or two applications to the oilstone almost invariably -round it off as shown. The bevel of <i>all</i> tools must be kept -quite flat and even, and when the tool is afterwards rubbed -on the oilstone to give a finish to the edge, another flat, -even bevel should be made. In the same figure at L is an -exaggerated view of the chisel, with its first long bevel -formed at the grindstone, and the second very small -bright bevel seen at the extreme edge of all such tools -when they have been set upon the oilstone. This second -bevel, slight as it is, you will at once understand makes -the angle of the edge a little larger, therefore you must -allow for it, and grind a little keener edge than you really -require.</p> - -<p>Now, all this is very simple and easy to understand, and -when you have mastered this much, you will be in a fair -way to understand more. The second part of the subject, -nevertheless, requires very close attention, and very likely -may not become quite clear to you when explained. I shall -therefore draw a line here, and make this lesson a special -paragraph, which you can look back to some other day,<span class="pagenum"><a name="Page_150" id="Page_150">[150]</a></span> -when you are grown from a boy-mechanic to a man, and -have had more experience in cutting and turning wood and -metal.</p> - -<p>The tools above described have their cutting -edges formed by the meeting of two planes -at a given angle,—these planes being the -flat bevels (or the flat top and one bevel) -formed by the grindstone. But in some tools three planes -meet to form an edge instead of two, and the angle of the -cutting edge is not the same as that of either of these, -although it depends upon them, and can be nicely calculated. -This calculation, however, requires a knowledge of -some higher branches of mathematics than the young -mechanic is supposed to be acquainted with, and therefore -a table is added instead, by which, when the angles of two -of these planes are known, the third may be at once -seen, which last determines, of course, the angle of the -edge.</p> - -<p>As an example, take the graver, of which you will find a -drawing among the other tools, but which I give again in -this place. M, Fig. 45, is the tool, looking at the face or -bevel which has been ground upon it, making a lozenge-shape -or diamond. But this face is a <i>third plane</i>, and the cutting<span class="pagenum"><a name="Page_151" id="Page_151">[151]</a></span> -edges, <i>a</i> and <i>b</i>, depend for their angles upon all three of -these. Now, for iron we want an angle of 60°. How are -we to make the edges, <i>a b</i>, of that exact size? The bar is -first of all square in section, like N, which would be its -shape before the third face or bevel is ground, and all the -angles are now right angles of 90° each. But instead of -this, we want two of them 60°, the other two being of no -importance. We simply proceed thus:—Determine which -angle is to become the point of the tool (it is no matter in -the present case, as all are alike), then grind away underneath -till the new bevel forms an angle of 45° with the -back (by which I mean the edge which runs along from the -sharp point towards the handle—the edge <i>x</i> in fig. O). -Trigonometry enables us to find out that an angle of 45° is -the one required, but you will find it in the table annexed -to this chapter, and an explanation of this table is also -given to enable you to use it easily. Thus ground, the -edges <i>a b</i> of fig. O will be each formed of two planes -meeting at an angle of 60°. You can make a gauge of -card or tin, P, to work by, of the required angle.</p> - -<div class="figcenter" style="width: 500px;" id="fig46"> -<img src="images/figure46.jpg" width="500" height="200" alt="" /> -<p class="caption">Fig. 46.</p> -</div> - -<div class="figcenter" style="width: 400px;" id="fig47"> -<img src="images/figure47.jpg" width="400" height="200" alt="" /> -<p class="caption">Fig. 47.</p> -</div> - -<p>In order to understand the use of this table, it is necessary -to give names to the several angles of a tool. That upon -the front or face of the tool, as A of the point-tool, is -called the plan-angle; that made by the upper surface and -the front edge, as B (<i>a</i>, being the angle in question), is -called the section angle, because, if you were to saw right<span class="pagenum"><a name="Page_152" id="Page_152">[152]</a></span> -through the central line lengthwise, this is the angle that -would appear at the point, viewing it sideways. Now, if -we look at C, Fig. 47, we shall be able to understand how the -front line, <i>b c</i>, is obtained, which constitutes one side of the -section angle of a tool. It results from the meeting of the -two diamond-shaped planes at the sides formed by the -grindstone, but is dependent also on the plan-angle. These -two side-planes are to be generally ground at an angle of<span class="pagenum"><a name="Page_153" id="Page_153">[153]</a></span> -about 3° from the vertical, which is to give the clearance of -the tool if held in a fixed position, as in the tool-holder of -a slide-rest, the tool being supposed horizontal. This is -in accordance with what I have before told you, viz., that -the cutting edge should be presented to the work at the -smallest possible angle, 3° being very small indeed. This -angle is generally measured by placing the side ground in -contact with a cone of wood or metal, turned to an angle -of 3°, such as D,—<i>k</i> being a tool the front of which is -evidently 3°; or a piece of tin, <i>l</i>, cut to the same angle, -and stood on its edge, will answer the same purpose. By -3°, I mean an angle of 3° measured on the circumference of -a circle, as I have already explained in a former page, such -angle being of course at the centre of the circle where the -lines drawn from the several degrees on the circumference -meet.</p> - -<p>Now, when you have ground these two surfaces, the line -<i>b c</i> of B (or C) will have a certain slope or inclination -depending on the plan-angle of the point. The exact -inclination of it may be therefore said to be accidental; but, -whatever it is, it becomes of great importance in the final -result, being one side of the angle which will give any particular -angle of cutting edge. And here the table comes -into use:—Suppose I wish to have an edge of 60°, for -cutting iron. Measure the <i>plan</i>-angle,—say it is 90°, -which is that of the graver; then, on the table, under the<span class="pagenum"><a name="Page_154" id="Page_154">[154]</a></span> -words “plan angle,” you will see 90°, and opposite, above -60° of “cutting edges,” you will see 45°. You have only -to grind back the upper face of the tool, until it makes an -angle of 45° (section angle) with the front edge or line, <i>b c</i>, -and the edges <i>x x</i> will be angles of 60°. Or take the tool -E, of which the plan angle is 120°, and suppose you want -cutting edges of 80°, for brass, opposite 120°, and above -80°, is 78° 5″. Grind back the top face to an angle of -78° 5″ (or 78½) with the point line, and it is done.</p> - -<p>Until you have practically proved it, you can have no -idea of the vast importance of having correctly-formed -cutting edges, and of placing them within a hair’s-breadth -of the proper position. But it is in slide-rest work especially, -and in cutting metal with tools held rigidly in one -position, that this is of such paramount importance. It -makes all the difference between cutting off a clean shaving, -and tearing from the material by main force a quantity of -disjointed particles, the latter process leaving a rough -unfinished surface, the former producing one as smooth and -polished as a sheet of glass; and the advantage of this -short table is, that you can at any time shape your own -tools for the particular work in hand.</p> - -<p>After you have had some practice in turning, you should -certainly learn to shape your tools from square bars of steel, -worn files, and broken steel tools of various kinds; and -before you have arrived at sufficient dexterity to do this<span class="pagenum"><a name="Page_155" id="Page_155">[155]</a></span> -entirely by yourself, you will get them roughly shaped for -you by the blacksmith, and then with grindstone and file -you will further perfect the angles for use. Steel does not -require, and must on no account be subjected to, a white -heat, or you will spoil it hopelessly; and you can always -heat it in a common fire, or in the little stove that I shall -describe in a subsequent chapter, to a temperature that -will allow you to bend it into any required form with the -hammer and anvil—a bright red being the utmost heat it -must be brought to.</p> - -<h3>POSITION OF CUTTING TOOLS.</h3> - -<p>We must now consider the mode of applying the edge of -a tool to the work, so as to produce the best effect. First, -we will consider the case of a gouge and chisel acting upon -soft wood.</p> - -<p><span class="pagenum"><a name="Page_156" id="Page_156">[156]</a></span></p> - -<div class="figcenter" style="width: 600px;" id="fig48"> -<img src="images/figure48.jpg" width="600" height="350" alt="" /> -<p class="caption">Fig. 48.</p> -</div> - -<p>In Fig. 48, A represents a piece of wood in the lathe, as -you would see it if you stood at one end of it, and a chisel -is being held against it. The arrow shows the direction in -which the wood is supposed to be revolving. Held thus, -the chisel would scrape, and its edge would be carried off -at once; it could not possibly cut. But, held as at B, it -would cut off a clean and continuous shaving as the wood -revolved against it, and this shaving would slide off along -the upper face, <i>b</i>, of the tool, so that you can see that this face -ought to offer the least possible resistance to it. The tool<span class="pagenum"><a name="Page_157" id="Page_157">[157]</a></span> -acts, in fact, like a very thin, sharp wedge, which divides -the material by pressure, which has to be great or slight -according as the edge is sharp and thin or the contrary. -Now, if you again look at A, you will see that this wedge-like -action cannot take place, so that the tool is in its -worst possible position.</p> - -<p>Between the two positions, however, here shown, are -several others at a greater or less angle to the surface of -the wood; but the smallest possible angle it can make is -the best, so long as the thickness of shaving removed will -suffice for your purpose. This rule holds good with all -tools, whether carpenters’ or turners’, which are made with -sharp-cutting edges. Care must be taken, however, that -the lower face of the tool does not rub against the work, -which, again, it is evident, limits to a given degree the -angle at which the cutting edge is to be applied to the -work.</p> - -<p>We now pass on to C, which represents the ordinary tool -for turning iron, held flat upon the rest, the position it -usually occupies. We see at once that in this case also we -have a scraping tool only, and that, although the angle of -the edge is far greater than that of the chisel, it must soon -be ground off by the action of the metal to which it is applied, -or of the hard wood, which is also cut in this way. -But with this form of tool we shall find it impossible to -apply it so as to cut in the best way; because if we lower<span class="pagenum"><a name="Page_158" id="Page_158">[158]</a></span> -the handle, as we did that of the chisel, the part below the -edge will rub against the work, while the edge itself will -be moved out of contact with it. Thus we are obliged to -hold the tool in the position first shown; but we may -therefore conclude that the <i>tool itself is a badly formed one</i> -for the intended purpose; and so it is, although you will -see it in almost every workshop in the kingdom. Let us -see what can be done to improve it. At D, I have represented -the same tool, but the blackened part shows what -has been filed away from the upper face, and the dotted -lines show that, when this has been done, a tool is made -very similar to the chisel for wood, and that it is also now -in a good position for <i>cutting</i> (<i>not scraping</i>), although it is -still held horizontally upon the rest. Shavings of iron -curl off the upper face of this, as wood shavings curl off -upon a chisel.</p> - -<p>If the angle, however, is too small, the edge will soon be -broken off, and the tool will dig into the work; hence the -necessity of knowing at what angle a tool ought to be -ground to cut any particular metal successfully.</p> - -<p>Such a tool as the last named, which is intended only to -cut with the front edge, and which is represented in E, is -called a single-edged one, because it only cuts in one -direction, but many others are double-edged, cutting the -shaving at once on the flat and edge—that is, paring it off -from the material below and also from the side. For<span class="pagenum"><a name="Page_159" id="Page_159">[159]</a></span> -instance, F is a cylinder of iron, from which a shaving is -supposed to be in process of being cut. It has to be removed -from the shoulder to which it is represented as still -adhering, and also from the flat surface, <i>e b</i>, around which -it was, as it were, once coiled. But this requires two cutting -edges, both acting at the same time, but in different -directions; and good mechanics therefore so form the tools, -and so use them, as to cut in both directions, which leaves -the work beautifully smooth and even.</p> - -<p>These tools are mostly used in the slide-rest, where their -true position, once determined, can be accurately maintained; -and it is, perhaps, only with the slide-rest that -perfect work can be done. There is, however, no reason -why you should not use tools of all kinds intelligently, and -understand exactly how they should be formed, and how -held. Suppose you have a tool correctly made by the aid -of the table of tool angles already explained, still looking at -fig. F, you can see that the smaller part of the roller is that -which is to be left finished, and that it ought to be quite -smooth, but the shoulder at <i>a</i> is not of the same degree of -importance. A tool fit for such work would evidently be -shaped on its <i>plan-angle</i> or face, like H in fig. C or I; and, -if held as seen, both edges would be brought into action at -the same time, as will be at once evident on inspection. -In practice, however, the two edges would not be allowed -to touch for their whole length, or the angle on the right<span class="pagenum"><a name="Page_160" id="Page_160">[160]</a></span> -would leave a scratch upon the finished work; therefore it -would be eased off a little, as at K, L. But this is evidently -as nearly as possible the shape and position to be given -to such a tool, and the edge which has to leave the -finished surface should, as it were, <i>follow</i> the other; the -right-hand angle being <i>just</i> and <i>only just</i> kept out of -cut.</p> - -<p>The hand-tools you will generally use are the heel-tool, -M, held on the rest as shown, which, you see, brings the -edge into cut at the least possible angle to the work, and -the nail-head, which is in fact a heel-tool of four faces, or, -if round, a heel-tool <i>all edge</i>, and which can be rolled over -as it gets blunted. To these add the graver, of which I have -already spoken. I have tried to show its position at O, with -the bevel of the face pointed in the direction of the shoulder, -and downwards; but it can be held face upwards also, and -in one or two other positions. Always remember that the -cutting edge is to be presented at a small angle with the -work, and you cannot go wrong if the tool is well formed. -The nail-head and heel-tools are single edged, and easily -ground without the table of angles, but the graver is a -double-edged tool, properly speaking, although only one -edge may perhaps be used.</p> - -<p>Having explained the principles upon which you have -to work as regards grinding your tools and holding them -when in use, I shall merely add a few remarks as to the<span class="pagenum"><a name="Page_161" id="Page_161">[161]</a></span> -action of the grindstone and oilstone, and the proper way -of using them.</p> - -<p>Always let the stone revolve towards you, as if you had -to turn it smooth with the tool you have to sharpen, except -when you cannot possibly do so without cutting grooves in -it. Chisels, knives, axes, planes, and all similar tools -with flat edges, are to be ground with the stone running in -that direction, by which means you will avoid giving them -a wire edge, as it is called (<i>i.e.</i>, a ragged-looking edge), -and it will instead be even and sharp; the filament of -metal being, as it were, driven back into the substance of -the tool, instead of drawn away from it. Gouges may be -ground in the same way, but must be rolled about to keep -up the form of edge. It is indeed the easiest way with -these to hold them <i>across</i> the stone, in the same direction -as its axis, and then, by rolling them over backwards and -forwards, you can give a very good shape to the edge, which -should run slightly to a point, or rather <i>tend</i> to one. They are -never to be ground square across, like that of the carpenter.</p> - -<p>It is generally necessary to have some sort of rest upon -which to lay the tools during the operation of grinding, -but do not trust to special contrivances for holding them -at the precise angle needed; rather trust to your own skill, -which will increase more and more by being severely exercised. -Always remember to grind your tools to a sharper -angle than will be ultimately required, that the final angle<span class="pagenum"><a name="Page_162" id="Page_162">[162]</a></span> -may be given by the oilstone. Of the latter there are -many kinds. Nothing probably can surpass a Turkey -stone, if good, but this varies considerably in hardness and -other qualities. There is a very quick-cutting, slightly -coarse stone from Nova Scotia, which is very serviceable, -as it does this tedious work with great rapidity, not, however, -putting on the tools a very fine edge, but one that -admirably suits for such as are to be used on metal. With -the rest, a rub or two on Turkey, or Arkansas, or Chorley -Forest stone, will impart a finish. Arkansas stone, however, -may be had coarse as well as fine; it is much liked -by some, but I prefer the Nova Scotia, as it cuts more -keenly, and even with the sharpest stone, setting tools is a -most laborious process.</p> - -<p>The young mechanic will find it very difficult at first to -hold the tool steady, and to move it to and fro upon the -oilstone so as not to give it any rolling movement, by -which the edge and bevel would be rounded, as I before -explained, which would in effect enlarge the angle of the -cutting edge, besides preventing it from being held at a -sufficiently small angle to the work to cut effectively. -Nothing but practice will overcome this difficulty; I shall -not therefore attempt to describe exactly how the tool -should be held and the sharpening effected, such description -being not only difficult, but, as experience has proved -to me, impossible.</p> - -<hr /> - -<p><span class="pagenum"><a name="Page_163" id="Page_163">[163]</a></span></p> - -<div class="figcenter" style="width: 500px;"> -<img src="images/header5.jpg" width="500" height="110" alt="" /> -</div> - -<h2 id="CHAPTER_X"><span class="smcap">Chapter X.</span></h2> - -<div> -<img class="dropcap" src="images/dropcap-w.jpg" width="100" height="120" alt="" /> -</div> - -<p class="dropcap">We now enter upon the actual work of the lathe, -which should be comparatively easy to understand -after the foregoing observations.</p> - -<p>Your raw material having been chopped or -shaved into a rough cylindrical form, you have to mount it -in the lathe. I may suppose it a piece of beech for a tool-handle. -If you have the cross-chuck, you should use it; -if not, you may use the prong instead. In either case, -centre the wood as truly as you can, so that, when the rest -is fixed near it, the piece may not be much farther from it, -as it revolves, in one place than another. Mind and screw -down the back poppit tightly upon the lathe-bed, and also -the rest, putting the latter as near the work as you can -without touching it. Now set the lathe in motion,—this -is tolerably easy, but to keep it in motion will probably -not be easy at all. It is one of those operations which<span class="pagenum"><a name="Page_164" id="Page_164">[164]</a></span> -require practice, because while your leg is at work upon -the treadle, your body must be firm and still, so that you -feel yourself free to use the tools without giving much -attention to what your leg is doing. After a while you -will do this with perfect ease. The wood is, of course, to -rotate towards you, and the surface will come in contact -with the edge of the tool as the latter is <i>held tightly down -on the rest</i>. Now, this is, after all, the real difficulty, for -every projection striking the tool tends to jerk it off the -rest, and this has to be resisted with some force. There is, -however, this advantage in hand-tools, viz., that they may -be held rigidly yet be allowed some slight play, according -to the peculiar exigencies of the work; and at first you -will save the tool by allowing it to yield slightly until the -roughest part has been cut away. Afterwards, there is to -be no movement except that required to make it follow the -curves or level parts of the work. Do your best first to -produce a cylinder, <i>i.e.</i>, a straight, even piece of wood, as -long as the required handle, and as large round as the -largest part proposed to be given it. It is the best plan at -first to copy a well-shaped handle, and to turn as many as -you want of that size exactly to the same pattern. This -will give you such an amount of practice in copying form, -as will stand you in good stead in after days; for it is not -easy at first to turn even two things exactly to pattern -and to <i>size</i>.</p> - -<p><span class="pagenum"><a name="Page_165" id="Page_165">[165]</a></span></p> - -<p>You must not expect to be able to run your tools along -the work like a professional or old hand at the lathe; you -must do the best you can. Hold the handle in the right -hand, and with the left grasp both rest and tool together, -and you will hold it firmly. Then you <i>ought</i> to run it -along right or left at the right speed and the right angle, -but you will be unable to do so yet;—never mind. Remember -the <i>principle</i> I have laid down as to the position -and angles of cutting tools, and trust to time and perseverance -to make you a good workman.</p> - -<p>The gouge is the easiest and best tool to use at first; -and you can do a fair amount of <i>smooth</i> work with it if you -know how, although smoothing and levelling is the special -work of the chisel. The gouge, however, is used for all -sorts of curves and hollows, and though the actual point -will only turn a groove if held still, the <i>side</i> of the cutting -part will, if the tool is steadily advanced, turn very fair -surfaces indeed. I strongly advise practice with this tool -before attempting to use any other. Your early work is of -little importance, and you may make up your mind to cut -several pieces into shavings and chips without very grand -success, even though you use a chisel; so I repeat, stick to -the gouge only for some time, until you can use it towards -left or right, and with either hand grasping the handle.</p> - -<p>With the chisel, far more care is required than with the -last named. It is altogether a more difficult tool to use.<span class="pagenum"><a name="Page_166" id="Page_166">[166]</a></span> -Its position may be described as follows, but practice alone -will render its use easy. Lay it first flat on the rest as you -would the gouge, and let it point upwards at a similar -angle, until it also is in the position the gouge would take, -ready to cut the piece of wood in the lathe, already turned -to the cylindrical form by the latter tool. You will find -one point or angle of the edge, the sharpest, reach the wood -before the other, and will see at once that this would be -liable to catch in, if the lathe were in motion—and so it -would. I shall suppose that this sharpest angle is on the -right-hand side as it lies flat on the rest, and against the -wood. Raise that angle so that the tool lies a little edgewise -on the rest instead of quite flat, when the angle of the -tool that is highest on the wood will be also raised off it; -the lower angle and remainder of the edge still being in -contact with it. This is its proper position, with the upper -angle out of contact with the work. You may turn it over -so that the keenest angle is the lower one, but then you -must raise the other, which is now the upper one, for under -no circumstances must the one that is uppermost touch the -wood. The chisel, therefore, never lies flat on the rest or -on the work, but always slightly raised to clear the upper -point, and in this position you have to keep it, making it -descend into hollows, and rise over mouldings, and cut -level places, almost without stopping an instant; and for -wood, especially soft wood, the lathe is always itself to be<span class="pagenum"><a name="Page_167" id="Page_167">[167]</a></span> -run at a very high speed, by putting the cord on the largest -part of the fly-wheel and smallest part of the pulley.</p> - -<p>To return to the supposed tool-handle. Having turned a -cylinder, begin at the ferule, which you must cut off a -brass or iron tube, or, which is easier, buy by the dozen or -by the pound ready cut. You will want them three-quarters -of an inch for your largest tools, and about three-eighths -for the smallest, with some of half an inch, and you can -then bore your tool-rack exactly true with centrebits of -these sizes. Turn the place down for the ferule, and take -care that you make a tight fit. Gauge with the callipers -first of all, and turn almost to size, then try it on once or -twice until it fits exactly.</p> - -<p>If you use the cross-chuck, you have this one great -advantage—you can take out your work to put on the -ferule, and replace it exactly as it was before, and it will -continue to run true. As, however, the piece in the present -case is but partially turned, it can be replaced with -sufficient accuracy upon the prong-chuck, especially if you -mark the side of the chuck, and of the piece of wood, and -take care to replace them in the same relative position. -You must now try with gouge and chisel to imitate the -pattern handle, remembering always to work downwards -from right and left into the various hollows—(you cannot -cut the fibres neatly if you try to go up-hill); and where -the two cuts meet in the hollows, you must do your best not<span class="pagenum"><a name="Page_168" id="Page_168">[168]</a></span> -to leave the least ridge or mark. You will be sure to need -a little glasscloth to finish off your work, but do without it -as much as possible, because it spoils the shape of mouldings, -rubbing off the sharp angles, which in many cases add -beauty to the work. If the piece of wood is longer than -necessary, cut it off with the chisel. In any case, you -must cut off a piece at the chuck end; and this being the -end of the handle which you will hold in your hand, the -ferule being at the end next to the back poppit, you will -cut it off neatly with the chisel in finishing it to the -required shape.</p> - -<p>You would hardly suppose it possible to turn off the end -of a piece squarely and accurately with the gouge, but it is -a good tool for the purpose. You must lay it on its side -upon the rest, so that its back or bevel rests flat against -the end of the piece from which the superfluous wood is to -be taken; the edge or point of the tool is then allowed to -cut the work by a slight movement of the handle. You -can only do it in this way, with the bevel against the piece -from which the cut is to be taken. Turned over to its -usual position, it will hitch in and spoil the work in a -moment. In the same way you can face up a bread-platter -or similar flat work; but such articles as these are not -mounted between centres, but screwed upon the taper -screw-chuck or the flat plate with the screw-holes, so that -you can get to the face of them. At first, however, until the<span class="pagenum"><a name="Page_169" id="Page_169">[169]</a></span> -work gets tolerably level, you may bring up the back-centre, -which will prevent the taper screw of the chuck from being -accidentally bent; and when all the rough part is cut -away, and the rim turned down, you can remove the back-centre -to finish the facing up. In this work, however, the -back and face do not need much turning, because the -platter is turned from plank wood, planed up truly on each -side, and cut roughly into the form of a circle. If accurately -planed, it will run true at once, and the small amount -of facing may be done with the gouge held as directed. -Afterwards it may be necessary to take a light <i>scrape</i> with -a <i>carpenter’s</i> chisel, which answers well for this. Then -finish up with glass or sand paper. Take care to make a -neat moulding to the edge, which will be about an inch -thick, and will therefore look very heavy unless turned off -so as to thin it down. A platter is a very good and useful -work for a beginner.</p> - -<p>In turning a platter you will certainly learn one lesson -in mechanics. You will find that it is very hard work to -turn anything that is larger than the pulley of your lathe, -and you will only be able to take a very light cut. Probably -you will find it the easiest plan to set the lathe in -rapid movement, and apply the turning-tool only for an -instant, and then to remove it until the work has recovered -its impetus, thus cutting it, as it were, by repeated brief -applications of the tool, instead of by one continuous cut.<span class="pagenum"><a name="Page_170" id="Page_170">[170]</a></span> -I do not mean that the tool is to be removed from the rest, -but only eased off for a second from the work. If the -latter is very large, and the pulley on the mandrel much -less in size, you can only work in this way, finishing with a -very light cut. There is a tool for the face of such flat -works, called a broad. It is like a broad chisel with the end -turned up at right angles to the side, only the edge is a -bevelled one and thick. They work well in hands accustomed -to them, but the gouge and chisel are sufficient for -your present need.</p> - -<p>I shall sketch here (Fig. 49) one or two articles not requiring -to be much hollowed out, which will help you to -decide upon such work as is suitable to a young mechanic -desiring, by steady practice and application, to become a -proficient at the lathe, and as soft-wood turning will -teach you more than that in hard wood, I shall direct -all the following to be made of it by gouge and chisel -alone.</p> - -<p><span class="pagenum"><a name="Page_171" id="Page_171">[171]</a></span></p> - -<div class="figcenter" style="width: 400px;" id="fig49"> -<img src="images/figure49.jpg" width="400" height="525" alt="" /> -<p class="caption">Fig. 49.</p> -</div> - -<p>These examples are not given as specimens of the rich -work which can be done in the lathe, but as easy examples -of elementary turning. No. 1 is a stand for an urn or hot -water jug, and a slight recess may be made in the upper -surface, in which a piece of cloth, or carpet, or oilcloth can -be glued, which will make a neat finish. No. 2 is a bread-platter, -showing how a little neat moulding takes away the -clumsy appearance of the thick board necessary for this<span class="pagenum"><a name="Page_172" id="Page_172">[172]</a></span> -purpose. No. 3 is a candlestick. The lower part or stand -is to be turned from a separate piece of thick board screwed -upon the taper-screw chuck. While it is in the lathe, the -hole must be made in the centre (or marked, if the piece is -not very thick) by holding a pointed tool a little on one -side of the centre, so as to describe a circle of the requisite -size. Into this will be fitted a tenon, fig. 3 <span class="smcapuc">B</span>, which is -turned on the pedestal, and which is to be glued into its -place. By and by you will learn how to cut a screw upon -such a tenon, which is a far more satisfactory method of -proceeding; at present glue will answer just as well. You -can make the upper part separate, forming the junction at -the line C (Fig. 49, No. 3), if you prefer it, or if your wood -is not long enough; but as you will not hollow out the top, -you may as well let it be cut out of one piece with the -pedestal. Turn the top quite level, drive in a piece of -stout wire, and point the end of it. Cut out a round piece -of tin to fit, and make a hole in the middle of it to let the -wire through; drop it over the point, and let it rest on the -candlestick; a wax candle can be spiked upon the wire, -and will stand firm.</p> - -<p>Figs. 7 and 8 are drawings of tool-handles. These are -the best shape to grasp in the hand, and they look neat -in the tool-rack. Tool-handles with a number of mouldings, -are not only absurd, but are uncomfortable to hold, -and not at all suited to their intended purpose. 9 and 10<span class="pagenum"><a name="Page_173" id="Page_173">[173]</a></span> -are other forms of mouldings, and are given merely to show -how angular and rounded forms should be combined to -produce a good effect. If these were to be made in hard -wood, they might be turned with beading and moulding -tools similar to those at A, B, C, D of this figure; such -tools are bevelled only on one side, and being held flat upon -the rest, cut the curves and hollows rapidly, and clean. -Sometimes a number of these are arranged side by side, so -as together to make up the outline of the intended moulding, -and being held in position by a handle designed for the -purpose, are presented all at once to the work as it revolves. -In other cases, a flat plate of steel is filed into shape, and -bevelled to form a compound moulding tool. Of course, -such contrivances greatly help the turner, especially if he -has to turn a number of articles of exactly the same pattern, -such as the pawns of a set of chessmen, or a set of -draughtsmen; but none of these tools answer upon soft -wood, because, as already explained, tools which have to be -held horizontally will cut and tear up the fibres of all -woods that are not very hard and compact in grain.</p> - -<p>Fig. 6 is a profile of a draughtsman, and fig. 6 <span class="smcapuc">B</span> shows -how they ought to be made, but for this you cannot use -soft wood, and had better make them of box and ebony, or -holly and ebony—(and, by and by, of black-wood and -ivory). A cylinder is first turned, then marked off as shown -with grooves cut by a parting-tool. The pieces are then<span class="pagenum"><a name="Page_174" id="Page_174">[174]</a></span> -separated with a fine saw, and a chuck is hollowed out to -fit them so that each can be readily turned upon the face. -The desired mouldings having been made on one side, the -disc is turned over in the chuck, and the other side operated -upon in the same manner.</p> - -<p>It is quite <i>possible</i>, you must understand, to cut these -out of soft wood, even pine or deal. We often see boxes of -toys, children’s wooden plates and cups, turned very neatly -of this material; but it is not worth while to use it if you -can obtain boxwood. Moreover, box can be stained black to -imitate ebony, and is very often made to serve instead of it.</p> - -<p>Figs. 4 and 5 are ring-stands for the toilette-table—very -useful presents these to mothers, sisters, and, last but not -least, lady cousins, and other young ladies too, perhaps, who -are not cousins. These can be made in a variety of ways, -and give great scope for the exercise of your powers of -design. The first is a simple pedestal on a stand, turned -quite smooth in an elegant and simple curve. The stand -is also made without elaborate mouldings, giving altogether -a chaste and elegant appearance to the design. The extremity -is tipped with ivory, and an ivory ring surrounds -the bottom of the pedestal. If this is made in plain deal, -and thoroughly well finished and varnished, it will look -very well. The nicest soft English wood, however, for this -is certainly yew, some of which is beautifully fine in grain; -and as it will take an excellent polish, it always looks<span class="pagenum"><a name="Page_175" id="Page_175">[175]</a></span> -well; moreover, it can be turned entirely with gouge and -chisel.</p> - -<p>This ring-stand will be made in two parts; the pedestal -being separately turned at one end, a tenon will have to be -made as in the case of the candlestick, and just above it -the wood is to be turned off a little as if you were going to -make a larger tenon. Over this a ring of ivory may be -slipped and glued on, and the two can then be turned -together. A carpenter’s chisel will do for the ivory, which -will be scraped into form by it. It may be polished with -a little chalk on a moist rag or flannel. You can buy odds -and ends of ivory from the turners in rings and solid -pieces, which will come in for all sorts of decorations, and -you should save all old handles of knives, tooth-brushes, -and such like, for a similar purpose. Both ivory and bone -smell very disagreeably when in process of being turned. -To tip such articles with ivory, you can drill a small hole -in the top of the pedestal with great care, and fit the ivory -after being turned into it; or you can, if the work is -larger, bore the ivory and slip it on the wood;—much -depends upon the size and nature of the work.</p> - -<p>The second ring-stand is of rather more elaborate construction. -The baskets are made of little turned pedestals fitted -into a round piece of wood to form the bottom, and into a -ring which makes the rim. Baskets of this form (even -apart from the ring-stand) are very neat and useful.</p> - -<p><span class="pagenum"><a name="Page_176" id="Page_176">[176]</a></span></p> - -<p>It is very easy to turn rings of any size. Mount a piece -of board in the lathe on the taper screw chuck—it need not -even be cut to a round form; then determine the size of -the proposed ring, and, holding a parting-tool upon the -rest turned round to face the work, mark two circles, -and deepen the cuts, until the ring falls off. Take care -that the outer one is cut through first. The ring thus cut -may be afterwards placed upon a cylinder turned to fit it, -and finished upon the outside, and then placed inside a -chuck of wood bored out to suit the work, and neatly -rounded off upon the interior surface. Of course, if you -have to make rings of bone or ivory which are already -hollow, you can at once run a mandrel or spindle of wood -or metal through them and subject them to the various -operations required.</p> - -<p>Mandrels, or tapered cylinders of brass or iron, fitted as -chucks to the mandrel of the lathe, are sold on purpose for -this work, but a wooden rod answers just as well, and costs -nothing. Turn such a rod a little tapering, and take care -not to drive the work too far upon it, because, although at -first you can safely drive it on very tightly, if it is of ivory or -bone, you will frequently find your ring suddenly split and -open when its thickness has been reduced to the required -standard. If a number of equal rings are required, it is -the best plan to turn a hollow cylinder and then saw off -the rings as you are directed to saw off the draughtsmen.<span class="pagenum"><a name="Page_177" id="Page_177">[177]</a></span> -They will, of course, have to be finished in a -chuck.</p> - -<p>If you look round any fancy warehouse in which Swiss -carvings are sold, you will see how beautifully soft white -pine can be worked in the lathe by keen tools and clever -hands. In Tunbridge, too, many thousands of soft-wood -articles are manufactured yearly, some plain and merely -varnished, and some curiously inlaid with coloured woods, -so that you need not despise such materials as willow and -sycamore and the various pine woods, which are all capable -of being made into pretty articles of one kind or another. -The varnish, however, for these is such as to coat them -with a glassy layer which does not sink into the wood. -Common rosin dissolved in turpentine or in linseed oil, -kept on the hob so as to get warm, answers well for these -deal articles, and is extensively used where the slight tinge -of yellow is not considered important. There are many -other much paler varnishes for works of greater value, or -where the white wood is to be carefully preserved. Any of -these can be had at oil and colour shops.</p> - -<p><span class="pagenum"><a name="Page_178" id="Page_178">[178]</a></span></p> - -<div class="figcenter" style="width: 350px;" id="fig50"> -<img src="images/figure50.jpg" width="350" height="600" alt="" /> -<p class="caption">Fig. 50.</p> -</div> - -<p>You will certainly find a difficulty in turning all exactly -alike the little pillars of these baskets. You should turn -several at once out of the same piece, separating them -afterwards. Thus your pattern will always be close to the -half-executed copy, which will somewhat assist you. Do -your best in this respect, but be specially careful, at any<span class="pagenum"><a name="Page_179" id="Page_179">[179]</a></span> -rate, to make all exactly the same length. One pillar is -shown separate, but you can design a pattern for yourself.</p> - -<p>Begin by turning a long cylinder; then set off the -respective lengths of the pillars. Turn one complete as a -pattern, and set the callipers to the largest part of it. -Then go to work upon a second, using callipers freely at -all parts of it. As these pillars will all be slender, you -will be in great danger of breaking them; therefore use -your tools lightly, taking only a very slight cut. But with -all your care you will find it difficult to turn a row of more -than two or three of the size wanted for such little baskets. -I shall therefore show you how to make a support to fit at -the back of the bar you are at work upon to support it -against the pressure of the tool.</p> - -<p>Fig. 50 gives a representation of one or two such supports, -which are often required in turning. The first is the -most simple, and is the one most generally in use, because -easy to make and to apply, and it answers tolerably well. -A is merely a piece of wood, about three-quarters of an inch -thick, cut as shown. This is stood up between the lathe-beds, -like C, and fastened with a wedge before and behind. It -allows the work in the lathe to revolve in the notch which -is cut in it, as is evident from the drawing. One, two, or -more such may be used if necessary. They must be carefully -adjusted, so as not to bend the piece which is to be turned, -and which is to be just supported, but no more. Where<span class="pagenum"><a name="Page_180" id="Page_180">[180]</a></span> -the <i>back-stay</i>, as this contrivance is called, comes in contact -with the work, the latter is to be left of the size it was when -this was adjusted to it as long as possible. It must then -be shifted a little, and that part which formerly rested -against it finished.</p> - -<p>B is another simple form of back-stay, capable of nicer -adjustment. The foot is that of a common rest, but if you -have not a spare one, any wooden support is quite as good. -Into this fits a turned part of the upright <i>x y</i>,—the upper -part, <i>y</i>, of this being planed flat. Neither should be of deal; -ash or elm is preferable. Thus the part <i>x y</i> can be raised -and lowered at pleasure in the rest-socket. The top part -is made of a half-inch board, about 2 or 2½ inches wide; -a slit is cut in it, and it is fastened to <i>x y</i> by a short bolt -and nut. Thus it is easy to raise and lower the end of this -part, and to put it nearer to, or farther from, the work in -the lathe, against which it can be adjusted with great -nicety. Although there are several forms of back-stay, of -more or less complicated construction, I know of none more -generally serviceable than this last, which the young -mechanic can make for himself. The notch should be -lubricated with soap, or, if the blackness is not of importance -(as when this part, which rotates in the notch, has -finally to be cut away), with a mixture of soap and blacklead. -This, remember, is always to be applied to wooden -surfaces that are to work easily upon each other.</p> - -<p><span class="pagenum"><a name="Page_181" id="Page_181">[181]</a></span></p> - -<p>It will sometimes happen that you require to bore a hole -through a long piece of wood, as would be the case in -making a wooden pipe, flute, bodkin-case, and many similar -articles. To hold these in a chuck only would be often -impossible, because the hole in the chuck would have to be -as deep at least as half the length of the piece to be -bored.</p> - -<p>For this kind of work, therefore, and for turning up a -point on the end of a cylinder of iron or steel, like that of -your back poppit, the following contrivance is used, which -is called a boring-collar or cone-plate. It is represented in -Fig. 50, D and E. This consists of a circular plate of -metal, three-quarters of an inch thick, turning upon a large -screw or pivot at its centre, by which pivot it is attached to -a short poppit head, fitting between the bearers of the lathe -as usual. There are six or eight conical holes bored round -the circular plate, each of a different size; and these are so -arranged as to height, or distance from the centre, that the -top one (being in a perpendicular line passing through its -centre and that of the bolt) is exactly as high as the axis -of the mandrel. Thus, if it is clamped in that position, -with the largest side of the conical holes next the mandrel, -a piece of wood might be held at one end in a chuck, while -the other might rest in such hole as was best suited to its -size, not actually passing through it, but resting in the -inside of the conical hole, in which it would rotate almost<span class="pagenum"><a name="Page_182" id="Page_182">[182]</a></span> -as freely and as truly as if it were supported by the ordinary -point of the back poppit.</p> - -<p>Sometimes it may be preferred to allow the end of such a -piece of work to project through the cone-plate, a collar -being turned on it to prevent it from going too far. A -tool-handle, for instance, of the pattern before given, may -be beautifully bored in the lathe by allowing the ferule to -rotate in one of the holes of the cone-plate, the shoulder -behind preventing it from going too far. The rest is -brought round in front of the end of the handle, and a hole -bored by a drill for wood; or, the point of a drill is brought -against it, while the other end (having had a slight hole -made by a centre-punch for the purpose) is allowed to -centre itself on the point of the back poppit. The screw of -the latter is then advanced, and the drill being prevented -from itself revolving either by being grasped by the hand -or a vice, a beautifully straight and even hole is rapidly -made.</p> - -<p>Fig. 50, F, shows the position of the various pieces. -The drill is here kept from rotating by a small spanner, the -handle of which comes against the bed of the lathe. A -great deal of work, both in wood and metal, is always -drilled in this way.</p> - -<p>For wood, a small nose-bit, or auger-bit, or one of the -American twist-drills, can be used, and this may be succeeded -by a larger, until the hole will allow of the introduction<span class="pagenum"><a name="Page_183" id="Page_183">[183]</a></span> -of a finishing-tool of some kind, held in the hand. -Of course the latter is not necessary in boring out handles -for the tang of a tool, but only in turning boxes for pencils, -needles, or other articles, which require to be neatly finished -inside as well as out; all these are to be bored before the -work is cut free from the superfluous wood out of which it -was turned. You can even use the cross-chuck for this -work.</p> - -<p>It matters little, when using the cone-plate, whether you -finish the turning of the outside before or after the boring -is done. Very generally the box or other article is bored -first, quite in its rough state, except that a short piece is -turned down to fit into a hole of the cone-plate; and, -keeping the latter in its place all the while, the wood is -turned down and polished before removing it from the -lathe. Sometimes, especially with metal, which is in no -danger of splitting, the cone-plate is removed as soon as -the hole has been made and replaced by the back-centre, -the point of which, entering the hole, retains the work in -its place while the outside is being fashioned. This of -course insures the exterior surface being exactly concentric -with the inside, which is often absolutely necessary in parts -of machinery; but if wooden articles are finished in this -way, there is great danger of their being split by the pressure -of the back-centre as the work grows thinner and -thinner under the action of the tools. Moreover, it must<span class="pagenum"><a name="Page_184" id="Page_184">[184]</a></span> -be remembered that the back-centre, being itself of a -conical form, will injure the form of the hole in metal by -making it wider at the mouth if used in this way, and -sometimes this may be of importance.</p> - -<p>There is a fault in the cone-plate which boys will understand, -and men, too, I imagine. <i>It costs money!</i> Therefore -I shall now show you how to make a substitute, which will -cost something under a shilling, if you do not mind a little -trouble; but, if you do, you will never make a good workman, -nor will you be good for much, I fear, in any way! A -metal cone-plate for a 5-inch lathe costs £2 at least.</p> - -<p>I shall suppose you want a cone-plate in which to -bore your tool-handles, for it is not easy to do this with -a gimlet, so that the tools, when inserted, shall stand -straight in their handles. If you have a 5-inch centre -lathe, <i>i.e.</i>, a lathe in which the central line or axis of -the mandrel is 5 inches from the lathe-bed (in which -case you can turn anything nearly 10 inches in diameter), -cut out of a piece of beech, 3 inches thick, a short -poppit 3½ inches high, of some such shape as seen in the -fig. G; and in the lower part (which must be cut to fit -between the lathe-bearers, and must be made square at the -sides and true, so that the whole will stand squarely across -the lathe-bed), either cut a mortice, <i>a</i>, for a wedge, or bore -a hole for a screw, which must have a plate and nut to fasten -under the bed like other poppits. Near the top, and exactly<span class="pagenum"><a name="Page_185" id="Page_185">[185]</a></span> -in the centre, bore a hole to receive the bolt K, similar to -that in the metal cone-plate already described, and which -will be tightened by a nut at the back. This supplies the -place of the short iron poppit, and now you have to contrive -something to replace the circular plate of holes. Cut -two or three strips of any tolerably hard wood, H (beech -will answer very well), 6 inches long, half an inch thick, -and 2 inches wide. Cut in these a slot and a round hole, -which must be carefully made with a centrebit. This hole -is to be for one of those in the usual round plate, so be -careful in making it. Work thus: Plane up the piece -from wood rather more than the half inch required; draw a -line exactly down the middle of it on both sides <i>e</i>, <i>f</i>; -choose a centrebit of the size you require; put the point -upon this line, about 1½ inches or more, according to the -size of the required hole, and bore steadily a little way -into the wood. Then turn it over, measure carefully so as -to get the precise spot right, and finish from that side. If -the centrebit is sharp, and the wood sound, you will now -have a neat round hole. Let the slot be also cut from both -sides of the piece of wood with a sharp chisel, taking care -that the centre of it agrees with the line that you made for -a guide.</p> - -<p>Three or four of these should be made, each with a different -sized hole, or more if required; but you can add new -ones at any time. The bolt, K, is to be made with a large<span class="pagenum"><a name="Page_186" id="Page_186">[186]</a></span> -head flat on the under side, and the upper part, above the -screw, is to be square for three-eighths of an inch, and the -slot in the pieces of wood must just fit this squared part. -Now, as this is three-eighths only, and the thickness of the -wood is four-eighths or half an inch, it is plain that the -nut will draw, and the head of the screw clamp this tightly. -You can, if you like, however, make the hole in the poppit -square also, and then let the squared part of the screw be -long enough to reach <i>almost</i> entirely through both pieces. -Then slip a washer (an iron plate with a hole in it like L) -over the end of the screw, and fix all with the nut. Thus -you have a boring collar with <i>one</i> hole, and this you can -raise or lower the length of the slot so as to get it exactly -the right height, and when it is so arranged, one turn of -the nut at the back will fix it.</p> - -<p>This you will find a very simple form of boring-collar, -easy to make, and of practical use. If you really take all -the care you can, and follow the directions I have given, I -do not see how you can possibly fail in constructing one. -You should have a sliding-plate with a hole for each size -of tool-handle ferule used, as you will frequently be making -these.</p> - -<h3>HOLLOWING OUT WORK.</h3> - -<p>As I have spoken of boring, I will go on to treat now of -the general practice of hollowing out chucks and boxes, -and such like. If this is to be done in soft wood, such as<span class="pagenum"><a name="Page_187" id="Page_187">[187]</a></span> -willow, no tool will answer so well as the hook-tools, of -which I have given drawings. But these are very difficult -indeed to use, owing to their tendency to catch in, or take -suddenly a deeper cut than was intended. Nothing but -practice will teach exactly how to use these tools; but then, -when the difficulty of so doing is once mastered, nothing -can be more rapid or more satisfactory than the work -which they will do. Small bowls are hollowed almost -instantaneously by their means in skilled hands; whereas, -with other tools, it becomes not only a tedious job, but if -it is done at all, it is but roughly, the wood having to be -rather scraped out than cut. Using, however, the back of -the gouge as explained before, in the directions given for -squaring up the end of a cylinder with this tool, it is -possible to hollow out soft wood with it, but not very -satisfactorily. In any case, other tools (generally a carpenter’s -chisel) must be used to work into the angle which -neither the gouge nor hook-tool can, of course, reach. -Hence it is generally so much easier to cut out boxes and -such like articles in box or <i>hard</i> wood, that this is nearly -always used by amateurs.</p> - -<p>The ordinary way to turn a box is as follows:—Prepare the -wood as usual, turning it cylindrical, using any chuck you -please for this work; cut off with the parting-tool rather -more than the box and its cover together will require, and -drive the piece thus separated into a cup-chuck. [You<span class="pagenum"><a name="Page_188" id="Page_188">[188]</a></span> -may, if you prefer it, screw upon the nose of the mandrel, -or upon the taper screw-chuck, the rough piece of the -proper length, instead of first turning a cylinder to cut -from. If you have several boxes to make of one size, the -cylinder method is to be preferred.] Turn it up again -quite true, for although it was correct before you cut it off, -it will not be so now. Square up the end, and turning -round the rest so as to stand across the face of the wood, -begin to hollow out <i>the cover</i>. Use either the round end or -pointed tool at first, and then a carpenter’s chisel or flat -tool to finish. Be very careful that the sides (I must call -it by this name, although a circle has not more sides than a -plum-pudding) are turned square to the bottom, or else, -when the cover is put on, it will perhaps fit just at the -entry, and be quite loose when fairly on; or, it may be -that it will be easy at first, and when you press it on, it -will be tighter and become split,—a very common but -unpleasant occurrence. Do not, moreover, turn down -these sides as thin as they will ultimately be; because, -after the box is hollowed and the cover fitted on, both will -have to be slightly turned together to finish them nicely. -Moreover, you may not wish your box to have plain sides, -but may prefer to mould them into a more elegant form. -All these little questions have to be duly considered in -turning, for a mistake is often made, and the work spoiled, -for want of a little timely consideration.</p> - -<p><span class="pagenum"><a name="Page_189" id="Page_189">[189]</a></span></p> - -<p>The next point on which you have to be on your guard is -this,—having turned out the cover, you have to cut it off, -not with a saw, but with your parting-tool. Now, be sure -to leave thickness enough for the top of the cover; or, just -as you think you have nearly severed the latter from the -rest of the piece of wood, you will see a beautiful little -ring tumble off,—sad relict of your box cover, which has -come to an untimely end.</p> - -<p>The sliding square of the turner, of which I gave a -description among the list of tools, will always enable you -to gauge both the depth to which the work is hollowed out, -and also the squareness of the inside to the bottom. But -if you have no turner’s square, you can easily gauge the -depth inside, and thus see how much is necessary to be -allowed for the thickness of the top. Keep the parting-tool -edgewise on the rest, which should be raised to such a -height that, when this tool is laid horizontally across it, it -will point nearly to the centre of the work, <i>i.e.</i>, the axis of -it. After the parting-tool has cut into the wood a little -way, widen the groove a little, and continue to give the tool -a little play right and left, unless its end is so much wider -than its blade generally that it will clear itself perfectly as -it goes deeper and deeper into cut. If it should bind, it is -almost certain to break, for it is a very thin tool; and it is -better to waste a little more of your material than to have -to replace a spoiled tool.</p> - -<p><span class="pagenum"><a name="Page_190" id="Page_190">[190]</a></span></p> - -<p>I shall suppose that you have now succeeded in cutting -off the cover; pick it up and lay it near you. Directions -are given generally to turn down next the flange upon -which the cover of the box is to be fitted, but this is not to -be wholly done yet, and you may proceed to hollow it out -as soon as you have turned down just so much of this flange -as will show you how much to leave in hollowing out the -box. If you <i>fit</i> the cover before you have hollowed out the -box, you will have the mortification of finding it a great -deal too loose when the box is finished, because the latter -will contract in size as soon as ever the solid core is -removed from it. <i>After</i> you have hollowed it out, you must -gauge the inside of the cover, and the outside of the place -that it is to occupy, with the in-and-out callipers, or with a -common pair, and turn the flange till it is almost correct -to this gauge, and only a very little larger than it ought to -be. When this is the case, do not trust any longer to the -callipers, but try on the cover again and again until you -get a nice fit. You must finish the flange with a chisel, -held flat; and again I repeat the caution about keeping it -truly square, so that the cover will hold equally tight in all -positions. When this is the case, leave it on, and give a -last touch to both box and cover together, when you ought -barely to be able to see the joint.</p> - -<p>You have now only to cut off the box as you did the -cover, using the same precautions. Before it is quite<span class="pagenum"><a name="Page_191" id="Page_191">[191]</a></span> -severed, however, you should give it a polish. Pick up -a handful of shavings, and while the work is revolving -as rapidly as possible, hold them with some pressure -against it. Every fibre will be at once laid smooth, and it -will look nice and bright at once. You can varnish it -afterwards if you like, or French-polish it. Varnish is -best for boxwood, and French-polishing requires special -directions, which I shall give you separately in a future -page.</p> - -<p>To be able to make a box <i>well</i>, with its cover well fitted, -is to be able to do all kinds of similar work. Yet in these -may be special <i>details</i> deserving notice. Probably, therefore, -when speaking in a future page of particular objects -which have to be turned, such special details will be more -fitting than if given here. I shall therefore pass on to -another part of the subject, namely, screwed and twisted -work.</p> - -<h3>SCREWS AND TWISTS.</h3> - -<p>Neither of these can be very accurately made without -special and somewhat expensive apparatus; but both can -with practice be done tolerably well by the young mechanic -with ordinary simple means. I need not describe a screw, -for all boys know what it is; and sporting boys, of which -in these days there are many, know what sort of <i>animal</i> a -screw is. Well, never mind. I am always riding a screw, -I believe, for it is my hobby, and there is a great deal of<span class="pagenum"><a name="Page_192" id="Page_192">[192]</a></span> -science in a screw; and as for the <i>variety</i> of the manufactured -article, there is plenty of it. There is the corkscrew, which -is, after all, not a screw, but a twist,—and this is often the -means of making men screwed; and the miserly screw, who -skins fleas for the sake of their fat; and there is the -mythical, invisible, moral (and im-moral) screw, which -hard-fisted men inflict upon their weaker brethren; and -there is the gigantic screw of the <i>Great Eastern</i> steamship; -and the minute, microscopic screw of the lady’s tiny -jewelled watch.</p> - -<p>There are several modes of cutting screws, in the lathe -and out of it. The small ones required for holding together -the different parts of machinery, as well as larger ones for -the same purpose, are always cut with stock and dies. -The very small ones used by watchmakers, and all below -one-eighth of an inch diameter, are made by the screw-plate. -But when either large or small screws are required -of great accuracy, they are invariably cut in the lathe, and -with the aid of mechanical appliances of the most delicately -accurate description. These are all metal screws. But the -young mechanic will often wish to put screwed covers to -his boxes, and to join various parts of his work by screwed -connections instead of glue; and all these may be cut in the -lathe by simple hand-tools skilfully applied, although the -operation is sufficiently fraught with difficulty to require a -great deal of practice before it can be done with certainty<span class="pagenum"><a name="Page_193" id="Page_193">[193]</a></span> -of success. At the same time, my young friends cannot -possibly do better than practise this operation, for there are -numberless cases in which screws cannot be conveniently -cut in any other way, and it is, further, an accomplishment -that will at once stamp them as skilful workmen.</p> - -<div class="figcenter" style="width: 400px;" id="fig51"> -<img src="images/figure51.jpg" width="400" height="325" alt="" /> -<p class="caption">Fig. 51.</p> -</div> - -<p>The tools required are represented at A, B, Fig. 51. A -is an outside, and B an inside screw chasing-tool. These -are always made in pairs, of exactly the same pitch, <i>i.e.</i>, -the outside tool being applied to the inside, the respective -notches and points will exactly fit into each other. If you -were to examine the under side of these tools, shown at C, -you would notice that the notches do not run straight, but -slanting. They are in fact parts of screw threads; and you<span class="pagenum"><a name="Page_194" id="Page_194">[194]</a></span> -could make a tool of this kind out of a common screw nut, -as I have shown you at D, only it would be too much hollowed -out to make a good tool.</p> - -<p>Now, supposing you were to hold the tool A flat on the -rest, while a cylindrical piece of wood revolved in contact -with it, you would cut a series of rings only; but if you were -at the same time to slide the tool sideways upon the rest, so -that by the time the wood had revolved once, the first point -of the tool would have just reached the spot which was occupied -by the second when you started, you would have -traced a screw thread of that particular pitch. This is what -you have to learn to do always, and with certainty, no -matter what pitch of tool you may be using, and it is easy -to understand how difficult the operation must be to a -beginner. Indeed, there are numbers of otherwise good -turners who have never succeeded in mastering this work. -Nevertheless it can be done, and, although difficult, it is -not so much so as might be supposed. Indeed, at first sight -it would hardly be believed <i>possible</i>, because each different -pitch of tool, and each different-sized piece of work, -requires a different speed of traverse to be given to the -tool. But a practised hand will strike thread after thread -without failure, and those whose trade is to make all sorts -of screw-covered boxes and similar articles, will execute -the work with as much speed and apparent ease, as they -would any ordinary operation of turning. I shall tell you<span class="pagenum"><a name="Page_195" id="Page_195">[195]</a></span> -by and by, however, of several ways to escape this difficulty -of screw-cutting,—lathes being fitted in various -ways to insure good work, in some cases by carrying -forward the tool at exactly the right rate of traverse, and -at others by moving along the work itself at the proper -speed, while the cutting tool is held immovably fixed in one -position,—and I will give one tool of great service which -will guide you in starting the ordinary chasing-tool; and -a good start is here truly “half the battle.”</p> - -<p>The chasing-tool must run from right to left for an -ordinary right-handed screw (and a left-handed one is very -seldom required), so that the young mechanic need not -trouble himself about it. Precise directions cannot be -given further than to have a rest with a very smooth and -even edge, which will not in the least hinder the traverse -of the chasing-tool, and to get the lathe into steady, -equable motion. Then hold the tool lightly, but firmly, -keeping it at right angles with the work. Allow it only -just to touch until you find you have got into the right -<i>swing</i>. It is all a matter of knack and practice; and if you -succeed quickly, you may congratulate yourself.</p> - -<p>The inside chasing-tool is used in precisely the same -way, running it from the outer edge of the hole inwards. -To some this is an easier tool to use than the outside -chaser. I cannot say that I find it so; especially as one -has to work more in the dark; unless the work is of large<span class="pagenum"><a name="Page_196" id="Page_196">[196]</a></span> -diameter like the cover of a box, and even then the work is -sufficiently difficult owing to the shallowness of the lid, -which necessitates the instant stopping of the tool for a -fresh cut. For you must understand that you have to -deepen the screw-threads very gradually, and it will take -several traverses of the tool to cut them to a sufficient -depth.</p> - -<p>The chasers require to be very sharp to cut wooden screws -neatly, but observe you must only rub the upper flat face -upon the oilstone, or, if a notch has been made by using -the tools upon metal (they will cut brass well with care), -grind them in the same way; the great secret being to hold -the tool quite flat on the stone. You will thus, even by -continual grinding, only thin the blade of the chaser, -which will thus last for a long time. A practised hand -will even cut a good thread with any flat piece of steel -filed into equal notches, but a screw-chaser is the only tool -really fit for the purpose.</p> - -<div class="figcenter" style="width: 400px;" id="fig52"> -<img src="images/figure52.jpg" width="400" height="475" alt="" /> -<p class="caption">Fig. 52.</p> -</div> - -<p>The most effectual remedy for the screw-cutting difficulty, -is unfortunately rather expensive in its best form. -But in another, it is by no means costly; and although it -may not look so well as the first, it is equally effective, and -extensively used by the turners at Tunbridge Wells, who -make those beautiful little inlaid boxes and other articles. -I shall explain this to you, therefore, first:—</p> - -<p>A, is a lathe-head, something like the one I have already<span class="pagenum"><a name="Page_197" id="Page_197">[197]</a></span> -described, but you will notice that the mandrel is a much -longer one, and has several short screws cut upon it, each -one being of a different “thread” or “pitch.”<a name="FNanchor_1" id="FNanchor_1"></a><a href="#Footnote_1" class="fnanchor">[1]</a> This -mandrel runs through two collars, so that, besides turning -round, it can be pushed endwise. Now, supposing<span class="pagenum"><a name="Page_198" id="Page_198">[198]</a></span> -I was to hold the point of a tool firmly against either of -the screws, and at the same time was to turn the pulley -and mandrel, you will understand that it would run backwards -or forwards in its collars, at such a rate as the -screw-thread compelled it to move. This is the plan of -the traversing mandrel; and now supposing that you had -a box held as usual in a chuck, and while the mandrel was -compelled to move endwise as described, you were to hold -a pointed tool against it, the tool would evidently cut a -screw-thread of exactly the same pitch as that upon the -mandrel against which the pointed tool first spoken of was -applied. But in practice, a single-pointed tool held against -the mandrel would not answer very well, and so the following -plan is adopted instead, which answers perfectly.</p> - -<p>Fig. 52, C, is called a half-nut. It has a set of screw-threads, -cut where the semicircular hollow is, which threads -fit one of the screws on the mandrel. A whole row of these -half-nuts are fitted to turn at one end upon a long bar, -so that either one can be raised up at pleasure to touch the -screw upon the mandrel, which has threads of the same -pitch as itself, B. These, then, are ranged under the -mandrel, and when it is desired to make it traverse in its -collars, one of these half-nuts is raised and kept up by a -wedge placed underneath it. When no screw is required, -a somewhat similar half-nut, but with merely a sharp edge -instead of a thread, is raised, and this edge falls into a<span class="pagenum"><a name="Page_199" id="Page_199">[199]</a></span> -notch or groove turned upon the mandrel, or sometimes a -back centre-screw is added like D, and when no screw has -to be cut, this is run up against the mandrel like an -ordinary lathe.</p> - -<p>In the more expensive traversing mandrels, although the -principle is the same, there is a little difference in the arrangement -of the different parts. The mandrel is not very -much longer than usual; and it has no screw-threads cut -upon it. But a number of ferules like K, are made each -with a screw upon its edge, and one of these of the desired -pitch is slid upon the end of the mandrel at <i>b</i>, fig. P, -and is there held by a nut or otherwise, so that it cannot -move out of its place. The half-nut is seen at <i>a</i>. It consists -of a piece of brass or steel of the form shown with a -hole in the middle, and a screw cut upon <i>each hollow</i>, so -that it is a circle or set of half-nuts of different pitches. -This slips over a pin at <i>a</i>, and when the screw <i>b</i> is turned, -it draws up this pin and the nut attached, until the latter -comes in contact with the ferule upon the end of the -mandrel. This is very neat but expensive. Now, by far -the cheapest and best way for the young mechanic, is to set -boldly to work to conquer the difficulty of chasing screws -by hand. There are even disadvantages in the expensive -form of a traversing mandrel, which render it by no means -a desirable mode of fitting up a lathe, and after all, the -length of screw which it enables one to cut is very limited,<span class="pagenum"><a name="Page_200" id="Page_200">[200]</a></span> -and in addition, it is not every day, nor probably once a -month, that screw-cutting will be necessary at all. My -advice, therefore, is, do not get a traversing mandrel until -you can cut screws well with the chaser. When you can -do this, you will be able to judge of the advantage or disadvantage -of one.</p> - -<p>By far the greater number of common screws are cut -without the lathe, by screw-plates, or stocks and dies, -and the nut, or hole into which such screws are to fit, -is cut with a tap. A screw-plate is a simple affair,—a -mere flat plate of steel, in which several holes are -drilled, which are afterwards threaded by screwing into -them taps, or hard cutting steel screws of the size required; -the plate is then hardened by being heated red-hot -and suddenly cooled, after which being much harder -than brass, iron, or steel which has not gone through such -process, it will in turn cut a thread upon any of these by -simply screwing them into it. But although this will -answer for small and common screws, it is not at all suitable -for better ones, because the thread is <i>burred</i> up, not -<i>cut</i> cleanly as it would be with a proper tool. A far better -plan is a stock and dies; the latter being practically a -hardened steel nut sawn in half, and fitted so that the two -halves can be pressed nearer and nearer together as the -screw thread becomes deeper. The dies are screwed up -by means of a thumbscrew opposite to the handle.</p> - -<p><span class="pagenum"><a name="Page_201" id="Page_201">[201]</a></span></p> - -<p>To use it, a piece of iron is filed up or turned to the -required size, which must be exactly that of the finished -screw. The dies are then loosened and slipped on to the -end of this screw-blank as it is called, and are then slightly -tightened upon it. All that is now required is to keep -turning the tool round and round upon the pin, which it -will soon cut into a screw thread. When the stock is at -the bottom or top, you may tighten the dies, and so work -up or down; but never tighten them in any other part. If -iron or steel is to be cut, use oil with the tool, but brass -may be dry. If the screw is of steel, heat it red-hot and -let it cool very gradually, to make it as soft as possible.</p> - -<p>The hole or nut, into which the screw is to fit, is to be -drilled so as just to allow the taper tap to enter about a -couple of threads; a wrench, or, if small, a hand-vice is -then applied to twist it forcibly into the hole, when the -thread will be completed. Take great care to hold the tap -upright, or else, if it is a screw with a flat head which has -to fit into it, it will not lie correctly, but one side of the -head will touch while the other is more or less raised.</p> - -<p>There are other modes of screw cutting, but at present I -need only mention one, which is used for wooden screws -alone. It is called a screw-box, and is only made to cut -one size, a tap being always sold to match. You can, however, -purchase any size you like, from a quarter of an inch -to 2 or 3 inches; but the latter are only intended for very<span class="pagenum"><a name="Page_202" id="Page_202">[202]</a></span> -large screws, such as are used for carpenters’ benches and -various kinds of presses. A screw-box looks like a small -block of wood with a hole in it, but if you take out two -screws you will find a blade of a peculiar shape, which -forms the thread by cutting the wood as it is screwed into -the hole in the box.</p> - -<div class="figcenter" style="width: 250px;"> -<img src="images/footer3.jpg" width="250" height="125" alt="" /> -</div> - -<hr /> - -<p><span class="pagenum"><a name="Page_203" id="Page_203">[203]</a></span></p> - -<div class="figcenter" style="width: 500px;"> -<img src="images/header3.jpg" width="500" height="110" alt="" /> -</div> - -<h2 id="CHAPTER_XI"><span class="smcap">Chapter XI.</span></h2> - -<h3>HARD-WOOD TURNING.</h3> - -<div> -<img class="dropcap" src="images/dropcap-w.jpg" width="100" height="120" alt="" /> -</div> - -<p class="dropcap">We now discard almost entirely the gouge and -chisel used for soft woods, and fall back upon -an entirely different set of tools, similar to those -used for metal, but ground to rather more acute -angles. These tools are held horizontally upon the rest, -because depressing the handles causes the bevel below the -edge to rub upon the work; and in addition, the grain of -hard foreign woods is such that it cannot well be cut by -placing the tool at a more acute angle, as would theoretically -be required. Hence we can only regard these as -scraping tools; but as such they will do excellent work in -skilful hands. I have said that we discard the gouge, but -there are some woods that will bear this tool, to take off the -roughest parts of the work, before the application of others. -The roughing-tool, however, may now be considered to be -the point-tool, and the round-end tool, or “round” as it is<span class="pagenum"><a name="Page_204" id="Page_204">[204]</a></span> -often called; a narrow one makes a good tool for this -purpose.</p> - -<p>Hard wood is easier on the whole to work than soft, -because we have for the purpose a large stock of tools of -all shapes, suitable to the various mouldings required. -Hollows, round-beading tools, compound and simple -moulding tools of various sizes, to say nothing of those -which are made for use with ornamental apparatus, such -as are required for fluting, beading, and eccentric work, -spirals, and so forth. It is indeed in hard wood that most -amateurs are accustomed to work; ebony and ivory, -singly or in combination, being more extensively used -than any other.</p> - -<p>To turn a cylinder, or any work requiring to be held at -both ends, you will invariably find the cross-chuck the best -to use,—the fork or prong not taking hold in the hard -material. Rough down to shape as before, using the gouge -if it will work, but keeping the rest as close as possible, -and only taking a light cut. Then finish roughing with a -round-tool, and proceed generally as in soft wood turning, -except inasmuch as you have to scrape instead of cutting -the work into form.</p> - -<p>In addition to the tools already described, you will have -to obtain a few beading-tools, if you want to do very good -work, for these give far more beautiful mouldings than you -can cut in any other manner. Fig. 53, A to C, represent<span class="pagenum"><a name="Page_205" id="Page_205">[205]</a></span> -these. The bevel is on the under side, and it is better to -interfere with it as little as possible, by always sharpening -the flat face only. If it should be <i>necessary</i>, however, to -touch the bevel, it must be rubbed by a slip of oilstone, -rounded on the edge, as used for sharpening gouges. -Conical grinders, revolving in the lathe, are also used, -especially for small beading-tools, to be fixed in the slide-rest. -In the same figure, D and E represent another useful -hard-wood and ivory tool. It is called the side-parting -tool; and it is usual to have several of these, the hooks -increasing in length. The edge is only on the extreme end -of the hook. These tools are used for economy’s sake to -cut solid blocks of ivory and hard-wood from the inside of -boxes, instead of cutting the material into a heap of useless -shavings. Similar tools, G, H, curved instead of rectangular, -serve to cut out a solid piece from the inside of a -bowl. In ivory work it is essential to use these tools, -because such material is very costly; $2.50 a lb., and upwards, -being a common price.</p> - -<p><span class="pagenum"><a name="Page_206" id="Page_206">[206]</a></span></p> - -<div class="figcenter" style="width: 600px;" id="fig53"> -<img src="images/figure53.jpg" width="600" height="350" alt="" /> -<p class="caption">Fig. 53.</p> -</div> - -<p>K is given to show what are meant by beadings. If -these are exactly semicircular in section, they are far -more beautiful in appearance than if of such curves as can -be roughly cut by a chisel. The bead-tools are beautifully -formed for this very purpose. To use the same side-parting -tool, you must proceed as follows, which you will understand -by the fig. L:—A common straight parting-tool or<span class="pagenum"><a name="Page_207" id="Page_207">[207]</a></span> -narrow chisel is first applied to the face of the work to cut -a deep circular groove or channel, as shown by the white -space at N, and in section at L. This allows the narrowest -of the hooked tools to be applied to <i>under-cut</i> the solid core -<i>x</i>. This being withdrawn, a rather longer hook is applied, -the hook being held downwards as at O, until it reaches -the spot where it is to work, when it is gradually turned -up (bevel below). Eventually, it is plain that the solid -core or centre block <i>x</i> will fall out entire, which may be -used for other purposes. M shows how a similar but -curved block can be removed from the inside of a -cup or bowl, the curved tool not requiring an entry to be -made for it, as it cuts its own way entirely from first to -last.</p> - -<p>P and Q show a ring-tool and the method of using it. -A recess is turned in the face of a piece of wood as if -it was intended to hollow out a box. The ring-tool is -then applied bevel downwards, and with the left cutting -edge a bead is cut half-through from the inside. The -right edge is then applied to the outside, and when the -cuts meet the ring neatly finished, will fall off. With this -tool you can turn them very rapidly, and they will require -only a rub of sand-paper to finish them.</p> - -<p>R, S, T are three more tools for hard wood. The first -two cut on the outside of the curved part all round. These -would be used to hollow out humming-tops and all similar<span class="pagenum"><a name="Page_208" id="Page_208">[208]</a></span> -articles, and to finish the insides of bowls, for which T is -also designed. Indeed, I might go on to describe all possible -shapes of curved tools, each intended for some special -work; but you will not do better than to go to Fenn, Buck, -or any tool-maker in London, or elsewhere, and pick out at -7s., or so, per dozen, all shapes and sizes, or if you live at -a distance and write to either of the above, they will select -you the most useful; and you can trust these tradesmen -and all first-class ones to send you no tools which are not -of the best quality.</p> - -<p>In finishing best work in hard wood, be very careful of -all sharp edges of mouldings. Sand and glass paper round -off these, and spoil the beauty of the work. If you are -<i>obliged</i> to use such substances, touch off again the edges -with very keen tools, which ought to leave brighter and -more beautiful surfaces than any sand-paper can produce. -Indeed, the secret of <i>finished</i> work in hard wood is to have -tools whose edges and bevels are <i>polished</i>. In ornamental -eccentric and rose-engine turning, where to use sand-paper -would be to ruin the appearance of it, the little drills and -cutters pass through three stages of sharpening, being -ground on the oilstone, finished on a slab of brass, fed with -oil and oilstone powder, and polished on a slab of iron with -oil alone or oil and rouge. After this every cut that is made -with them reflects the light; and as the surface is otherwise -purposely grailed or dulled by cutting a series of fine light<span class="pagenum"><a name="Page_209" id="Page_209">[209]</a></span> -rings with a point tool, the pattern itself shows out clearly -and lustrously.</p> - -<h3>TURNING BRASS AND OTHER METALS.</h3> - -<p>I shall now teach you how to turn iron and brass, which, -though harder than wood, are not very difficult to cut, if -you go to work in a proper manner and understand how to -use your tools. What these are like I have already told -you, and also how to mount a bar in the lathe by using the -driver or point-chuck with a carrier. If the piece to be -turned is <i>not</i> a bar, you will have to drive it into a chuck -of wood, or clamp it upon a face-plate, or in a self-centring -chuck if you have one.</p> - -<p>I shall suppose, first of all, a mere straight bar of iron, -centred at the ends, as I have shown you. Take off the lathe-cord -that you use for wood, and fit one to go upon the largest -part of the mandrel pulley, and the smallest upon the fly-wheel. -When you now put your foot upon the treadle to work -at your usual speed, you will find the mandrel turn quite -slowly; but I may at once tell you, that what you lose in -speed you gain in power. Set your rest for iron (which is -not that used for wood, but one with a broad, flat top) so -that it stands a little below the central line of the lathe -mandrel and work, which will bring the edge of the tool -exactly <i>upon</i> that line. This is always the position of the -tool for metal-turning, at any rate for iron.</p> - -<p><span class="pagenum"><a name="Page_210" id="Page_210">[210]</a></span></p> - -<p>Begin by trimming the end of the bar next to the back -centre. Use a graver, held as I directed you; that is, with -the bevel flat upon the <i>face</i> of the iron, which is in this case -the <i>end</i> of it. Only let the point cut, and a very little of -the edge beyond it, and do not expect to take a <i>deep</i> cut so -as to bring off a thick shaving. In metal work you will -always have to proceed slowly, but nothing is more pleasant -when once you can do it well.</p> - -<p>You will at first have to experimentalise a little as to the -exact angle at which to hold the tool, but you will soon find -out this; and the advantage of hand-tools is, that you can -always <i>feel</i> as well as <i>see</i> how they are working, and can -ease them here and there to suit the material. It is rather -difficult at first to hold the tool still in metal-working, but, -like all else, it becomes easy by practice; so much so, that -to hold the tool steadily in one hand is not only possible, but -is the mode always followed by watchmakers. While you are -about it, you should turn the graver over and try it in other -positions; for although the two sides of the bevel nearest to -the point are the only ones to be used, these may be applied -in either direction, because they are both sharpened to angles -of 60°, and so long as you present them at the correct angle -(the smallest possible in respect of the work), it matters not -which face of the tool lies uppermost. After squaring off -one end, the approved plan is to remove the carrier, reverse -the bar, and do the same to the other end. Then begin to<span class="pagenum"><a name="Page_211" id="Page_211">[211]</a></span> -turn from the right hand. Place the graver as before, with -the point overlapping the end very slightly (so as only to -use the extremity of the cutting edge close to the point), -and take off a light shaving along the bar for a distance -of about half an inch, or even a quarter, keeping the edge -of the graver which is on the rest in one position, and -moving the tool, not by sliding it along the rest, but by -using the point upon which it lies as a pivot. It is very -difficult to describe this exactly, but Fig. 52, O, will help to -explain it. The tool is to rest upon one spot, and the point -to move in short curves like the dotted lines, being shifted -to a new position as you feel it get <i>out of cut</i>. The left -hand should grasp the blade and hold it tightly down upon -the rest, while the right moves the handle to and fro as -required. The curved dotted lines are necessarily exaggerated, -but the <i>principle</i> of the work is this, whether -you use a graver or a heel-tool. You should turn about -half an inch quite round, and then go on to the next, by -which you will always have a little <i>shoulder</i> upon the work -for the tool to start upon, and this will be nice, clean, bright -metal, and will not blunt the tool. But if you go to work -differently, so that the edge of the tool comes continually -in contact with the rough outside of the iron caused by -the heat of the fire, and which is exceedingly hard, the -point of the tool will be quickly ground down, while the -iron will not be cut into at all.</p> - -<p><span class="pagenum"><a name="Page_212" id="Page_212">[212]</a></span></p> - -<p>I need tell you no more about turning a <i>bar</i> of iron in -the lathe, because the above directions apply in all cases; -but if you have to turn the <i>face</i> of a piece of metal that is -carried in a chuck of some kind, you should always work -<i>from</i> the middle towards the edge, and if the graver is -used, its bevelled face will lie towards you during the process. -Take care to chuck the metal very firmly, for it is -most annoying to have it suddenly leave the chuck or shift -its position after you have been at the trouble of turning -part of it truly. In such case it is very difficult to replace -it exactly as it was before, and all your work has in consequence -to be gone over again. When taking the final -cut, or before, if you like, dip the end of the tool into water, -or soap and water, and see the effect. The surface turned -in this way will be highly polished at once, and the tool -will cut with much greater ease, so that a large, clean -shaving will come off. When using a slide-rest, you will -find it always better to keep water just dripping upon the -work and point of the tool; but there is a drawback, nevertheless, -to this plan, for, as might be expected, it makes a -mess and rusts the lathe, and sometimes the work as well, -so the water must be constantly wiped off it.</p> - -<h3>THE SLIDE-REST.</h3> - -<p>I shall now pass on to describe a mechanical arrangement -called a slide-rest, of which there are two separate and distinct<span class="pagenum"><a name="Page_213" id="Page_213">[213]</a></span> -forms, one for metal and one for ornamental turning -in ivory and hard wood. The ornamental work that can -be done I shall pass by for the present, because few boys -are provided with the costly apparatus required, and I am -rather addressing those young mechanics whose tastes incline -them to model machinery and to practise the various -operations of mechanical engineering on a small scale. To -such a slide-rest is an <i>almost</i> necessary addition to the lathe, -for there is a great deal of work which, I may say, cannot -be done without it; for instance, boring the cylinders of -engines (except small ones of brass), turning the piston-rods -and various pieces which require to be accurately -cylindrical and of equal size, perhaps for the length of a -foot or more. Hand-work has accomplished <i>something</i> in -this way in olden days, but the inability of workmen to -advance beyond a certain standard of perfection with hand-tools -alone, became such a hindrance to the manufacture of -the steam-engine, as improved by Watt and others, that -had not Maudsley, Naysmith, and others developed the -principle of the slide-rest and planing machine, we should -not yet have lived to see those gigantic engines which tear -along like demon horses with breath of fire, at the rate of -sixty miles or more in as many minutes. So likewise -would various other machines, which now appear absolutely -necessary to supply our various wants, have stood in their -primitive and imperfectly developed forms; for it is necessary,<span class="pagenum"><a name="Page_214" id="Page_214">[214]</a></span> -before constructing a machine, to have the means of turning -cylindrical parts truly, and producing perfectly level plates -where required.</p> - -<p>The object of a slide-rest is to provide means for holding -a tool firmly, and giving it a power to traverse to and fro -and from side to side, so that by the first we may be able -to cause such tool to approach or recede from the work, -and by the second we may cause it to move in a perfectly -straight line along its surface from end to end. This is -accomplished in the following manner:—The drawing -being a representation of one of the first machines constructed -for the purpose. A rectangular frame, A, of iron -is carried by a pair of strong uprights, B B, fixed to the -sole-plate, C, by which it is attached by a bolt to the bed -of the lathe. Lengthwise of this frame runs a screw, prevented -by collars from moving endwise, but which can be -turned round by the winch-handle, D. Thus a nut through -which this screw passes, and which only has endwise -motion, will, when the latter is turned by its handle, -traverse it from end to end in either direction, according -as the screw may be turned from right to -left or the contrary. This nut is attached to the under -part of a sliding-plate, E, which has a part projecting -between the sides of the frame, and also two others on its -outside, by which it grasps the same with great accuracy, -and is prevented from any shake or play as the whole<span class="pagenum"><a name="Page_215" id="Page_215">[215]</a></span> -with the nut is made to traverse to and fro along the -frame.</p> - -<p>Lengthwise of this sliding-plate, that is, in a direction -the opposite to that of its own traverse, are two bars bevelled -underneath, fixed exactly parallel to each other, which are -so arranged to guide the cross traverse of another plate -with chamfered edges to fit the bevels of the guide bars. -This second plate has on its upper surface two clamps -which secure the tool. It is plain, then, that by this arrangement -the two required movements are attained, the -lower plate sliding along in one direction parallel with the -lathe-bed, and the other across it. In the original rests, -this upper plate with the tool was moved by hand, and in -the modern rest for ornamental turning (which this was -also constructed for) the same is done, but a hand-lever is -added for the purpose.</p> - -<p>But although a similar arrangement is needed for metal, it -is plain that the top plate should have a more easily regulated -motion, and that we should be able to advance the tool as -near the work as may be desired, and then to retain it -securely at that distance while giving the necessary movement -in the direction of the length of the object to be turned. -The method of effecting this is at once suggested by the -screw and nut of the lower part, and by merely adding to -the top a similar arrangement, the desired end is at once -attained.</p> - -<p><span class="pagenum"><a name="Page_216" id="Page_216">[216]</a></span></p> - -<div class="figcenter" style="width: 400px;" id="fig54"> -<img src="images/figure54.jpg" width="400" height="450" alt="" /> -<p class="caption">Fig. 54.</p> -</div> - -<p>The actual construction of such rest varies somewhat, -but Fig. 54, H, shows it in its most ordinary form. The -lower part is, of course, to be clamped down securely to the -lathe-bed, there being a projection below which is made to -fit accurately between the bearers similar to that beneath -the poppits. This projection secures the correct position -of the rest, of which one frame or plate will travel lengthwise<span class="pagenum"><a name="Page_217" id="Page_217">[217]</a></span> -of the bed, while the other will move exactly at right -angles to it. But in the <i>compound</i> slide-rest, which is very -general, there is also a third circular motion, by which the -upper part can be set at any angle with the lower, instead of -being permanently fixed at right angles to it. By this the -tool can be made to approach the work more and more as -it passes along it; and it will therefore cut deeper at one -end of its traverse than at the other. The result will be -that what is thus turned will not be a true cylinder, but a -cone, <i>i.e.</i>, it will be larger at one end than the other, -although otherwise smooth and even.</p> - -<p>We are thus provided with the most valuable addition to -the lathe ever devised by mechanics, and it is no longer a -question of the strength and skill of the workman whether -we can produce a perfect piece of work, but simply of the -accuracy with which the lathe and rest are constructed, and -of the form and condition of the tools to be used. The latter -are not exactly like those ordinarily used, although the -principle of the cutting angles already laid down needs to -be adhered to even with more unfailing attention than that -required for the correct formation of hand-tools. Moreover, it -is plain that—here we shall no longer feel whether the tool -is working as it ought to do—we shall be unconscious of -the precise amount of <i>strain</i> that is being brought to bear -against its edge, and if it is by chance working in a bad -position, at a wrong angle, we cannot re-adjust it in a<span class="pagenum"><a name="Page_218" id="Page_218">[218]</a></span> -moment as we could a hand-tool by a slight movement of -the fingers or wrist.</p> - -<p>Hence you will see at once how very important it is that -tools for the slide-rest should be shaped with the <i>most rigid -adherence</i> to correct principles; and, further, that they -should be so fixed in the slide-rest as to meet the work at -the precise angle, and at the height exactly suited to the -material of which it is composed. As regards the latter -point, it may be taken as an almost invariable rule that the -work should be attacked on its axial line (that is, a line -that would run from end to end of it dividing it lengthwise -into equal parts, or, as it would commonly be named, its -<i>middle</i> line). If the tool meets it above this, it is most -likely that it will rub against it, and the point will be out -of cut. If it meets it below, there will be a tendency for -the point to catch in, and the work to roll up upon the face -of the tool, which, in fact, it very often does with careless -workmen, and then there comes a smash of some kind—lathe -centres snapped off, the tool broken, the bar bent -beyond remedy, and possibly the operator’s toes made unpleasantly -tender.</p> - -<p>The most common slide-rest tool for outside work is -that given at H². It is made straight, as shown, or bent -sideways to right or left to cut shoulders on the work, or -enter hollows, or creep sneakingly round corners, or any -other of those crooked ways in which man delights; but<span class="pagenum"><a name="Page_219" id="Page_219">[219]</a></span> -whether straight or not, these tools have all most commonly -the cranked form shown here. This gives the tools -a <i>slight</i> degree of elasticity—not very much, because that -would only injure the perfection of the work; therefore -they are not very considerably cranked. The angles are -ground as directed in the table of tool-angles, and if the -point is too low, slips of iron are placed below the shank -upon the tool-plate of the slide-rest; if too high, the grindstone -must be resorted to; and the advantage of these -cranked tools is, that they can be ground down several -times without being brought too low to be packed up with -iron slips to the right level. Thus a cranked tool is by far -more advantageous for the slide-rest than one made straight -like those used for hand-turning. For inside work, however, -or “holing,” the crank form is not possible, unless -the hole is of large size, and so, for this purpose, straight -side-tools are used, like K.</p> - -<p>If the tool is well placed, as well as correctly made, -nothing can be more easy and delightful than slide-rest -work. You merely advance the tool to take the required -cut (beginning generally at the right-hand end of the bar), -and then gently turning the other handle, you will see it -traverse along, as if work was a pleasure to it, as it ought -to be to all young mechanics. Not infrequently, however, -instead of this even, steady work, the tool jumps and -catches, or rubs and shrieks: it is out of temper, I suppose;<span class="pagenum"><a name="Page_220" id="Page_220">[220]</a></span> -at any rate, in some one or more particulars it needs -correction.</p> - -<p>Although with the slide-rest you can generally venture -upon taking a deeper cut than you could with hand-tools, -it is by no means well to hurry the work. At first, -especially before it has become cylindrical, the tool will -only cut partly round its surface, and the work is done in -an uncomfortable, jerking, dissatisfied sort of way, and the -deeper you drive the tool the worse it is; but as soon as -the outer skin is off, and the work has become cylindrical, -a long, clear, bright shaving curls off pleasantly from end to -end, and the surface ought, if the tool is wetted, to become -at once of a finished appearance.</p> - -<p>You should always, with a slide-rest, take the whole run -of the piece from end to end to a certain depth, and then, -commencing again at the end, repeat the same process, and -so on until the required size is almost attained. When it -is, take out the tool with the pointed end which has been -in use, and insert one freshly sharpened with a broad point, -getting it so placed as to cut the shaving both from the -surface below, and from the shoulder to which it is attached -at the side, as I explained to you in the chapter on grinding -and setting tools, and which must be well understood -before you can hope to make good work with tools rigidly -fixed in a slide-rest. With this tool, kept wet with soap -and water (or soda water, which is better for this than for<span class="pagenum"><a name="Page_221" id="Page_221">[221]</a></span> -your stomach), take a <i>very</i> light shaving from end to end, -taking especial care to turn the handle which gives the -traverse slowly and <i>evenly</i>. If you stop, or almost stop, -the tool will be sure to draw a little deeper into cut, which -will make a scratch upon the work, or, it may be, plough -a groove, and so far spoil the appearance of it.</p> - -<p>Whenever you finish turning any bar that has been -centred at each end, be careful to leave the centre marks -just as they were when the work was in the lathe. The -ends will have been otherwise trimmed off at the very commencement, -and it may happen that at some future day it -may be desired to re-mount the piece for repair, when, if -these marks are gone, and new centres have to be drilled, -the whole will run so much out of truth that it will have to -be entirely re-turned from the commencement. Do not, -therefore, fancy that these centre marks are unsightly, and -forthwith file them out, but be content to leave them.</p> - -<p>Slide-rest tools, made in the ordinary way, are so far -troublesome in use that if they get broken you must have -them re-forged, and few country smiths know anything -about such matters. I have a tool now lying by me made -by a smith (true, it was a Welsh smith), and although I -stood by and explained how it should be done, and cut one -out of a piece of wood, it never arrived at a proper shape, -and was never even placed upon the rest. I keep it as old -Izaak Walton kept the Londoner’s artificial fly, viz., “to<span class="pagenum"><a name="Page_222" id="Page_222">[222]</a></span> -laugh at,” and as a caution to all concerned, never to go -to a country blacksmith for slide-rest tools. The following -plan answers very well for many kinds of outside work, -and is on the whole a plan that may be satisfactorily followed -by the young mechanic.</p> - -<p>Instead of having the tools constructed from a large bar -of steel half an inch or so in the square, they are made of -short pieces about an inch long, fitted into a peculiar -holder.</p> - -<p>The advantage of this arrangement consists in the ease -with which you can make your own tools out of broken -round, triangular, or square pillar files, small chisels and -such like. These can be shaped by the grindstone alone, -and the blacksmith will not have to be called into requisition. -I shall give you two forms of tool-holders, more -or less simple, because I may suppose my young mechanic -to be fast growing into an old hand, and able to appreciate -differences in these arrangements.</p> - -<p>Fig. 55, A, B, represents two of such holders, one for -round, the other for flat steel cutters. You can see at once -that when these are upon the bed of the rest, they form a -tool with cranked end, as previously described, and can -therefore be used in precisely the same manner. I shall -give no directions for <i>making</i> these tool-holders, which are, -nevertheless, very simple affairs, and can be readily understood -from the drawings here given.</p> - -<p><span class="pagenum"><a name="Page_223" id="Page_223">[223]</a></span></p> - -<div class="figcenter" style="width: 400px;" id="fig55"> -<img src="images/figure55.jpg" width="400" height="450" alt="" /> -<p class="caption">Fig. 55.</p> -</div> - -<p>Another form is shown at C. The part <i>d e</i> is a clamp, -which is separately drawn at <i>f</i>. This, like the last, enables -one to use all sorts of odds and ends for tools. There are -several other patterns of tool-holders, arranged either to use -the little pieces of square, round, or triangular steel bars, -so that one side, at least, of these may remain without -grinding, and others in which two entirely new faces must -be given to the tool by the grindstone. The latter are, -perhaps, generally the best, because you can then, with the<span class="pagenum"><a name="Page_224" id="Page_224">[224]</a></span> -aid of the table of tool-angles, shape your cutters very -accurately to the work required of them.</p> - -<p>Although such tool-holders and cutters are generally -used for metals, there are others intended for wood; and -constructed to hold miniature gouges and chisels, which -perform their work admirably. A capital tool for outside -work, Fig. 55, E, which was used extensively at Portsmouth -dockyard for brass turning, is made simply by filing off at -an angle of about 45° a round short bar of steel. This -angle, however, is unusually small for brass and gun-metal, -80° being better. For iron it will answer better, because -though filed, or rather ground at 45°, the cutting edge, a -little way from what may be called the point of the tool, -is nearer 60°.</p> - -<p>Similar to these last are the tube gouges, short bits of -steel tube ground off and sharpened. These fixed in a -holder answer beautifully for soft wood, and do not “catch -in.” If the holder is bent so as to bring the tool into -proper position, inside work can be rapidly effected by -these, such as hollowing out large bowls and similar heavy -work. All this can, of course, be done rapidly with the -slide-rest, so far as regards the removal of the greater part -of the wood. But in the case of a bowl, in which a curve -predominates over a straight line, hand-tools must be used -to finish it (generally the inside hook-tool). This last is, -in fact, almost identical with the tube gouge; for the<span class="pagenum"><a name="Page_225" id="Page_225">[225]</a></span> -slide-rest, and that which makes it so difficult a tool to -use, is that, being a hand-tool, and subject to slight unintentional -changes of position upon the part of the workman, -it catches in, and is either wrenched out of the hand, -or a piece is chopped off the wood. Rigidly held in the -slide-rest, the exact angle, once found, is of course maintained.</p> - -<div class="figcenter" style="width: 150px;"> -<img src="images/footer1.jpg" width="150" height="125" alt="" /> -</div> - -<hr /> - -<p><span class="pagenum"><a name="Page_226" id="Page_226">[226]</a></span></p> - -<div class="figcenter" style="width: 500px;"> -<img src="images/header4.jpg" width="500" height="110" alt="" /> -</div> - -<h2 id="CHAPTER_XII"><span class="smcap">Chapter XII.</span></h2> - -<div> -<img class="dropcap" src="images/dropcap-i.jpg" width="100" height="120" alt="" /> -</div> - -<p class="dropcap">I now propose to assist the young mechanic in -special work, instead of continuing general -directions. This will enable me to explain to -him various lathe appliances, and other details -of mechanical work hitherto passed by.</p> - -<p>Of all models which boys (and very big boys too) are -desirous to construct, the steam-engine holds the chief -place, and deservedly so; for every boy calling himself -mechanical, ought to know how this is made, and the -general <i>principles</i> of its construction as well. However, I -am aware, from experience, that many a youngster, who is -even in possession of a model engine, is utterly ignorant of -the cause of its motion; although it is a great delight -to them to see the steam puffing out, and the wheel -revolving “nineteen to the dozen,” as schoolboys say. -Now, an engine is a very simple affair, and can be easily -explained; and, as I wish my readers to work rationally,<span class="pagenum"><a name="Page_227" id="Page_227">[227]</a></span> -I shall show them what they have to do before I tell them -how to do it.</p> - -<div class="figcenter" style="width: 400px;" id="fig56"> -<img src="images/figure56.jpg" width="400" height="500" alt="" /> -<p class="caption">Fig. 56.</p> -</div> - -<p>A, Fig. 56, represents a cubical vessel of tin or any<span class="pagenum"><a name="Page_228" id="Page_228">[228]</a></span> -other substance. By cubical, I mean that all its sides are -squares, and all exactly equal; each side in the present -case is to be 1 inch wide and long, or a square inch. B is -a similar vessel, 1 foot cube. It contains, therefore, 1728 -cubic inches, or is 1728 times as large in capacity as the -first. Now, if I were to fill the little vessel with water and -tip it into the second, and put a lamp under it, the water -would all soon boil away, as it is called. It would be -converted into steam; and the quantity of steam it would -produce would exactly fill the larger vessel, without exciting -any particular pressure upon its sides.</p> - -<p>Steam, thus allowed plenty of elbow room, is like a lazy -boy; it will play and curl about very prettily, but will do -no work. We must put some sort of pressure, therefore, -upon it—confine it, and we shall soon see that, by struggling -to escape, it will serve our purpose, and become a -most obedient workman. We have, therefore, only to put -double the quantity of water into our larger vessel, that is, -<i>two</i> cubic inches. We will put on a cover tightly, adding -a pipe through which to pour in the water. Soon we shall -have the steam formed as before; but it has no longer room -enough, and out it comes fizzing and roaring, very savage -at having been shut up in so small a cage. And we can -make it work too, for if we set up a little fan-wheel of tin -right in its way, we shall see it spin round merrily enough; -or if we cork the tube lightly, we shall find this cork soon<span class="pagenum"><a name="Page_229" id="Page_229">[229]</a></span> -come out with a bang. We have, in fact, already constructed -a steam-engine and a steam-gun on a small scale. -The pressure in this case is, indeed, not great, but what it -is I must now try to explain.</p> - -<p>The air or atmosphere, which surrounds us on all sides, -exercises a pressure upon everything of 15 lbs. on every -square inch of surface. If our little cubical inch box of -tin had no air inside it, and no steam, but was absolutely -empty, each side, and top, and bottom would have 15 lbs. -pressure upon it; which would be evident if it were not -very strong, for it would sink in on all sides directly, just -as much as if you were to <i>add</i> a weight of 15 lbs. when it -was full of air, as it would ordinarily be.</p> - -<p>When I spoke of the larger box being exactly filled -with steam from the evaporation of the cubic inch of water -poured from the smaller box, I supposed it empty of air. -The steam from that quantity of water, occupying the place -of the air, would also be of the same pressure, 15 lbs. per -square inch of surface; and as this only balances the pressure -of the atmosphere, which would be, in such a case, -pressing in on all sides, the steam would not show any -pressure; just as, if you put equal weights into each scale of -a balance, the beam of it would remain horizontal, neither -scale showing to the outward senses that it had any pressure -upon it. But in the second case, we have doubled the -quantity of steam, but compelled it to occupy the same<span class="pagenum"><a name="Page_230" id="Page_230">[230]</a></span> -space; therefore we have now real, visible pressure of 15 lbs. -upon each square inch; and if we again halve the space -which the steam has to occupy, or double the quantity of -water, we shall obtain a pressure of 30 lbs. beyond the -pressure of the atmosphere.</p> - -<p>Let us now disregard atmospheric pressure, and fit up -such an apparatus as Fig. 56, D. Here we have first our -small box, closed on all sides, and from it a small tube -rising and entering into the bottom of a larger one, which is -very smooth in the inside; in this is a round plate or disc, -called a piston, which fits the tube nicely, but not so tight -as to prevent it from moving up and down easily; and let -a weight of 15 lbs. be laid upon it. Let us suppose this -large tube or cylinder to be 1700 times larger than the -cubic inch box, into which water is to be poured till full. -Now we heat it as before, and when 212° of heat are -attained by the water (which is its boiling-point) when it -begins to be converted into steam, the piston will be seen -to rise, and will gradually ascend, until quite at the top of -the tube, because the steam required exactly that amount -of room.</p> - -<p>Now we have arrived at the same conclusion which we -came to before; for you see that not only has the cubic inch of -water become a cubic foot of steam (<i>about</i> 1700 to 1728 of its -former volume), but it is supporting 15 lbs. weight, which -represents that of the atmosphere, and if we could get rid<span class="pagenum"><a name="Page_231" id="Page_231">[231]</a></span> -of the latter, a solid weight of 15 lbs. would be thus supported. -Now, still neglecting the atmospheric pressure, -suppose instead of 15 lbs. we add another 15 lbs., making -the weight 30 lbs., down goes our piston again, and stands -at about half the height it did before. We have thus, as we -had previously, a cubic foot of steam made to occupy half a -cubic foot of space, giving a pressure (which is the same as -supporting a weight) of 30 lbs.</p> - -<p>I ought, perhaps, to add in this place, however, that -under 30 lbs. pressure, or atmospheric weight and 15 lbs. -additional, the water would not become steam at a temperature -of 212°, but it would have to be made much hotter, -until a thermometer placed in it would show 252°.</p> - -<p>So far we have seen what a cubic inch of water will do -when heated to a certain degree, and at first sight it may -not seem a great deal. Far from being light work, however, -this is actually equal to the work of raising a weight -of 1 ton a foot high. Let us prove the fact. Suppose the -tube or cylinder to be square instead of round, and that -its surface is exactly 1 square inch, how can we give 1700 -times the room which is occupied by the water? It is plain -that the piston must rise 1700 inches in the 1-inch cylinder -or tube, carrying with it, as before, its weight of 15 lbs.—that -is, it has raised 15 lbs. 1700 inches, or about 142 <i>feet</i>. -But this is the same as 15 times 142 feet raised 1 foot, -which is 2130 lbs. raised 1 foot, very nearly a ton, the latter<span class="pagenum"><a name="Page_232" id="Page_232">[232]</a></span> -being 2240 lbs. So, after all, you see that our little cubic -inch of water is a very good labourer, doing a great deal of -work if we supply him with sufficient warmth.</p> - -<p>Now this is exactly the principle of the ordinary steam-engine: -we have a cylinder in which a piston is very nicely -fitted, and we put this cylinder in connection with a boiler, -the steam from which drives the piston from one end of the -cylinder to the other. In the first engine that was made, -the cylinder actually occupied the very position it does in -our sketch; it was made to stand upon the top of the boiler, -a tap being added in the short pipe below the cylinder, so -that the steam could be admitted or shut off at pleasure. -But it is plain that although our little engine has done some -work, it has stopped at a certain point; there is the piston -at the top, and it cannot go any farther; we must get it -down again before it can repeat its labour.</p> - -<p>How would you do this, boys? Push it down, eh? If you -did, you would find it spring up again when you removed -your hand, just as if there were underneath it a coiled steel -spring; by which, however, you would learn practically -what is meant by the <i>elasticity</i> of steam. Besides this, if -you push it down, you become the workman, and the engine -is only the passive recipient of your own labour. Try -another plan; remove the lamp, and see the result—gradually, -<i>very</i> gradually, the piston begins to descend.</p> - -<p>Take a squirt or syringe, and squirt cold water against<span class="pagenum"><a name="Page_233" id="Page_233">[233]</a></span> -the apparatus. Presto! down it goes, now very quickly indeed, -and is soon at the bottom of the cylinder. But we -may as well try to get useful work done by the descent of -the piston as well as by its ascent.</p> - -<p>Set it up like Fig. 56, E. Here is a rod or beam, <i>b a c</i>, -the middle of which is supported like that of a pair of -scales. From one end we hang a scale, and place in it 15 -lbs.; and as the piston sinks the weight is raised, and exactly -the same work is done as before. Thus was the first engine -constructed; but instead of the scale-pan and weight, a -pump-rod was attached, and as the piston descended in the -cylinder this rod was raised, and the water drawn from the -well. This, however, was not called a steam-engine, because -the work is not really the effect of the steam, which is only -used to produce what is called a vacuum (<i>i.e.</i>, an empty -space, devoid of air) under the piston. In fact, the up-stroke -of the piston was only partly caused by steam, and the rod -of the pump was weighted, which helped to draw it up.</p> - -<p>I must get you to understand this clearly, so that the -principle may become plain—“clear as mud,” as Paddy -would say. I told you that the air pressed on every square -inch of surface with a force of about 15 lbs. We do not -feel it, because we are equally pressed on all sides—from -within as well as from without—so that atmospheric pressure -is balanced. Sometimes this is a very good thing. -We should, I think, hardly like to carry about the huge<span class="pagenum"><a name="Page_234" id="Page_234">[234]</a></span> -weight pressing upon our shoulders, if something did not -counteract it for us, so that we cannot feel it. Indeed, if -it were otherwise, we should become flat as pancakes in no -time—“totally chawed up.”</p> - -<p>But sometimes we should prefer to get rid of the air -altogether—and I can tell you it is not easy to do so, unless -we put something into its place; and we want perhaps -simply to get rid of it, and make use of the room it occupied. -We require to do this in the present instance, and -in fact we have just done it. If the whole space below the -piston, when we begin to work, is filled with water, it is -plain there can be no air below it; and when the steam has -raised it, there is still no air below it, but only steam. -We then apply cold to the cylinder by removing the lamp -and squirting cold water against it, which has the effect of -reducing the steam to water again, which will occupy 1 -inch of space only. We, therefore, now have a space of -1600 cubic inches with neither air nor water in it; and -so, if the piston is 1 inch in size, there will be the 15 lb. -pressure of the atmosphere upon it, and nothing below to -balance it, for we have formed a vacuum below it, and of -course this 15 lb. weight will press it rapidly down. It did -so; and we therefore were enabled to raise 15 lb. in the -scale-pan. You will know, therefore, henceforth, exactly -what I mean by a vacuum and atmospheric pressure. It is, -you see, the latter which does the work when a vacuum is<span class="pagenum"><a name="Page_235" id="Page_235">[235]</a></span> -formed as above; but you can easily understand that it -might be possible to use both the atmospheric pressure <i>and</i> -the pressure of steam as well, which is done in the condensing -steam-engine.</p> - -<p>In the earliest engine, called the <i>Atmospheric</i> for the -reason above stated, the top of the cylinder was left entirely -open, as in our sketch; but the condensing water was -not applied outside the cylinder, but descended from a -cistern above, and formed a little jet or fountain in the -bottom of the cylinder at the very moment that the piston -reached its highest point. Down it, therefore, came, drawing -up the pump-rod. When at the bottom the jet of -water ceased. Steam was again formed below the piston, -which raised it as before; and the process being repeated, -the required work was done. A boy, to turn a couple of -taps, to let on or off the water or steam, was all the attendance -required.</p> - -<p>For some time the atmospheric engine, the invention of -Newcomen, was the only one in general use; and even this -was, in those days (1705-1720), so difficult to construct -that its great power was comparatively seldom resorted to, -even for pumping, for which it was nevertheless admirably -suited. The huge cylinder required to be accurately bored, -while there were no adequate means of doing such work; -and although the piston was “packed,” by being wound -round with hemp, it was difficult to keep it sufficiently<span class="pagenum"><a name="Page_236" id="Page_236">[236]</a></span> -tight, yet at the same time to give it adequate “play.” -Then, another drawback appeared, which, though of less -importance in some districts, absolutely prevented the -introduction of this engine into many parts of the country. -The consumption of coal was enormous in proportion to -the power gained. We can easily understand the reason of -this, when we consider the means used for producing a -vacuum in the cylinder below the piston. The water introduced -for the purpose, chilled, not only the steam, but -cylinder and piston also; and therefore, before a second -stroke could be made, these had to be again heated to the -temperature of boiling water. The coal required for the -latter purpose was therefore wasted, causing a dead loss to -the proprietor.</p> - -<p>So matters continued for some time, until a mathematical -instrument-maker of Glasgow, named Watt, about the year -1760, began to turn his attention to the subject; and having -to repair a model of Newcomen’s engine belonging to the -University of Glasgow, the idea seems to have first struck -him of condensing the steam in a separate vessel, so as to -avoid cooling the cylinder after each upward stroke of the -piston. This was the grand secret which gave the first -impetus to the use of steam-engines; and from that day to -this these mighty workmen, whose muscles and sinews -never become weary, have been gradually attaining perfection. -Yet it may be fairly stated that the most modern<span class="pagenum"><a name="Page_237" id="Page_237">[237]</a></span> -form of condensing engine in use is but an improvement -upon Watt’s in details of construction and accuracy of -workmanship. For Watt did not stand still in his work; -but after having devised a separate condenser, he further -suggested the idea of closing the top of the cylinder, which -had hitherto been left open to the influence of the atmosphere; -and rejecting the latter as the means of giving -motion to the piston, he made use of the expansive power -of steam on each side of the piston alternately, while a -vacuum was also alternately produced on either side of it -by the condensation of the steam.</p> - -<p>The atmospheric engine was thus wholly displaced. -The saving of fuel in the working of the machine was so -great, that the stipulation of the inventor, that one-third -of the money so saved should be his, raised him from -comparative poverty to affluence in a very short time. -Watt, however, had still to contend with great difficulties -in the actual construction of his engines. He was in the -same “fix” as some of my young readers, who are very -desirous to make some small model, but have little else -than a pocket-knife and gimblet to do it with. For there -were no large steam-lathes, slide-rests, planing and boring -machines, procurable in those days, and even the heaviest -work had to be done by hand, if indeed those can be called -hand-tools which had frequently to be <i>sat upon</i> to keep -them up to cut. It was therefore impossible for Watt to<span class="pagenum"><a name="Page_238" id="Page_238">[238]</a></span> -carry out his designs with anything like accuracy of workmanship, -else it is probable that he would have advanced -the steam-engine even further towards perfection than he -did. In spite of these drawbacks, however, this great -inventor lived to see his merits universally acknowledged, -and to witness the actual working of very many of these -wonderful and useful machines.</p> - -<p>The first necessity which occurred from closing the -cylinder at both ends was the devising some means to -allow the piston-rod to pass and repass through one end -without permitting the steam to escape. This was effected -by a stuffing-box, which is represented in Fig. 57, A, B,—the -first being a sectional drawing, which you must learn -to understand, as it is the only way to show the working -details of any piece of machinery. We have here a -cylinder cover, <i>a</i>, which bolts firmly to the top of the -cylinder, there being a similar one (generally without any -stuffing-box) at the other end or bottom of the same. On -the top of this you will observe another piece, which is -marked <i>b</i>, and which is indeed part of the first and cast in -one piece with it. Through the cylinder cover, <i>a</i>, is bored -a hole of the exact size of the rod attached to the piston, -which has to pass through it, but which hole, however well -made, would allow the steam to leak considerably during -the working of the piston-rod.</p> - -<div class="figcenter" style="width: 500px;" id="fig57"> -<img src="images/figure57.jpg" width="500" height="425" alt="" /> -<p class="caption">Fig. 57.</p> -</div> - -<p>To obviate this, the part <i>b</i> is bored out larger, and has<span class="pagenum"><a name="Page_239" id="Page_239">[239]</a></span> -a cup-shaped cavity formed in it, as you will see by inspecting -the drawings. Into this cavity fits the gland, <i>c</i>, -which also has a hole in it, to allow of the passage of the -piston-rod. This gland is made to fit into the cavity in <i>b</i> -as accurately as possible; and it can be held by bolts as in -the fig. A, or be screwed on the surface as shown at B, in -which latter case the greater part of the interior of <i>b</i> is -screwed with a similar thread. The piston-rod being in -place, hemp is wound round it (or india-rubber packing-rings<span class="pagenum"><a name="Page_240" id="Page_240">[240]</a></span> -are fitted over it), and the gland is then fitted in -upon it, and screwed down, thus squeezing the hemp or -rubber tightly, and compelling it to embrace the piston-rod -so closely, that leakage of steam is wholly prevented. -Whenever you have, therefore, to prevent steam or water -escaping round a similar moving-rod in modelling pumps -or engines, you will have to effect it in this way. The -piston was also packed with hemp or tow, either loosely-plaited -or simply wound round the metal in a groove -formed for the purpose. In Fig. 57, C and D, I have -added drawings of a piston, so made, partly for the purpose -of again explaining the nature of sectional drawings. In -this one, C, you are shown the end of the piston-rod -passing through the piston, and fastened by a screwed nut -below, a shoulder preventing the rod from being drawn -through by the action of this nut. The hemp packing is -also shown in section, but in the drawing D the groove is -left for the sake of clearness.</p> - -<p>In all your smaller models you will have to pack your -piston in this way, except in those where you entirely -give up all idea of <i>power</i>. The little engines, for example, -sold at $1 and upwards, with oscillating cylinders, have -neither packed pistons nor stuffing-boxes; the friction of -those would stop them, and escape of steam is of no great -consequence. It will, however, be found advantageous to -turn a few shallow grooves round these unpacked pistons<span class="pagenum"><a name="Page_241" id="Page_241">[241]</a></span> -after they have been made to fit their cylinders as accurately -as possible, like fig. C. These fill with water from -the condensation of steam, which always occurs at first -until the engine gets hot; and thus a kind of packing is -made which is fairly effectual.</p> - -<p>In Fig. 58 I have given a drawing of Newcomen’s -engine, in case you would like to make a model of one; -but I do not think it will repay you as well for your labour -as some others. There is the difficulty of the cistern of -cold water and the waste-well; and the condensation of the -steam is a troublesome affair in a small model, so that, on -the whole, I should not recommend you to begin your -attempts at model-making with the construction of one -of these. I shall, however, add a few directions for this -work, because what I have to say about boring, screwing, -and so forth, will apply to all other models you may desire -to construct.</p> - -<p>The cylinder, in this case, will be more easily made by -obtaining a piece of brass tubing, which can be had of any -size, from 3 or 4 inches diameter to the size of a small quill. -The first you will often use for boilers, the latter for steam -or water pipes. You can also obtain at the model makers—Bateman, -for instance, of High Holborn—small taps and -screws, and cocks for the admission of water and steam, -and all kinds of little requisites which you would find -great difficulty in making, and which would cost you more -in spoiling and muddling than you would spend in buying -them ready made.</p> - -<p><span class="pagenum"><a name="Page_242" id="Page_242">[242]</a></span></p> - -<div class="figcenter" style="width: 400px;" id="fig58"> -<img src="images/figure58.jpg" width="400" height="600" alt="" /> -<p class="caption">Fig. 58.</p> -</div> - -<p><span class="pagenum"><a name="Page_243" id="Page_243">[243]</a></span></p> - -<p>The drawing is given on purpose to show the best and -easiest arrangement for a model. It has all parts, therefore, -arranged with a view to simplicity. A is the boiler -made of a piece of 3-inch brass tubing, as far as <i>a</i>, <i>b</i>, <i>c</i>, <i>d</i>, -the bottom being either of brass or copper at the level of -<i>a</i>, <i>b</i>; the upper domed part may be made by hammering -a piece of sheet brass, copper, or even tin, with a round-ended -boxwood mallet upon a hollowed boxwood block, of -which T, T is a section. You should make one of these if -it is your intention to make models your hobby, as it will -enable you to do several jobs of the same kind as the present. -Probably you will not be able to make the dome semicircular, -or rather hemispherical; but at all events, make it -as deeply cupped as you can—after which, turn down the -extreme edge one-sixteenth of an inch all round to fit the -cupped part exactly. This requires a good deal of care and -some skill. If you find that you cannot manage it, make -your boiler with a flat top instead. Whichever way you -make it, a very good joint to connect the parts is that -shown in section at V.<a name="FNanchor_2" id="FNanchor_2"></a><a href="#Footnote_2" class="fnanchor">[2]</a> The edge of the lower part is -turned outwards all round; that of the upper part is also -turned outwards, first of all to double the width of the -other, and is then bent over again, first with a pair of pliers<span class="pagenum"><a name="Page_244" id="Page_244">[244]</a></span> -and afterwards with a hammer, a block or support being -placed underneath it. All this is done by the manufacturer -with a stamping machine on purpose, and would be -completed by the Birmingham brass-workers before I could -write the description. It can, however, be done without -any more tools than shown.</p> - -<p>You will often need a tinman’s boxwood mallet with one -rounded end and one flat one, which, of course, you can now -turn for yourself, as it is an easy bit of work. With the -rounded end you can cup any round piece of tin; but it -requires gentle work; do it gradually by hammering the -centre more than the edges. I will show you presently how -to do similar work by spinning in the lathe, which is a -curious but tolerably easy method of making hollow articles -of many kinds from round discs of metal without any seam.</p> - -<p>After you have hammered the joint of the upper and -middle parts together, you must solder them all round with -tinman’s solder. For this purpose you require a soldering-iron -represented at W. This is a rod of iron, flattened and -split at the end, holding between the forked part a piece of -copper, which is secured to the iron by rivets. I should not -recommend a heavy one, not so heavy nearly as what you -may see at any blacksmith’s or tinman’s shop, because your -work will be generally light, and such irons are all top heavy -to use. The end, which may be curved over as shown, will -require to be <i>tinned</i>, for without this it will not work at all<span class="pagenum"><a name="Page_245" id="Page_245">[245]</a></span> -well. File the end bright, and heat it in the fire nearly red -hot. Get a common brick, and with an old knife or anything -else, make a hollow place in it—a kind of long-cupped recess -like a mussel shell, if you know what that is, and put a little -rosin into it. Take your iron from the fire, and holding it -down close to the brick, touch it with a strip of solder, which -will melt and run into the cavity. Now rub the iron well in -the solder and rosin, rub it pretty hard upon the brick, and -presently you will see it covered with bright solder, from -which wipe what remains in drops with a piece of tow. -The iron is now fit for immediate use; but remember, the -first time you heat it red-hot, you will burn off the tinning, -and you must file it bright again, and repeat the process. -So when you want to solder, heat the iron in a clean fire, -until, when you hold it a foot from your nose, you find it -pretty warm; and avoid a <i>red</i> heat. You will now find, -that when the soldering-iron is hot, it will not only melt -but pick up the drop of solder; and as you draw it slowly -along a joint (previously sprinkled with powdered rosin, or -wetted with chloride of zinc, or with Baker’s soldering -fluid), the solder will gradually leave the iron, and attach -itself to the work in a thinly-spread, even coat.</p> - -<p>The secret of soldering is to have the iron well-heated, -and wiped clean with a bit of tow, and to apply it along -the joint so slowly and steadily that the tin or other metal -will become hot enough just to melt solder. Try to solder,<span class="pagenum"><a name="Page_246" id="Page_246">[246]</a></span> -for instance, a thick lump of brass; file it bright if at all -tarnished—for this must invariably be done with all metals. -You will be unable to do it at first, for the moment the -solder touches it, it will be chilled, and rest in lumps, which -you can knock off directly when cold. Now place the brass -on the fire for a few seconds until hot, and try again; the -solder will flow readily as the iron passes along it, for it is -kept up to the melting-point until it has fairly adhered. -This is why in heavy work a large iron is required; it -retains heat longer, and imparts more of it to the metal to -be soldered. But you will find it often better to use a light -soldering-iron, and to place the brass-casting upon the bar -of the grate for a short time. You may, indeed, often work -without any soldering-iron as follows:—</p> - -<p>Heat the pieces to be soldered (suppose them castings -and not thin <i>sheets</i> of metal) until they will melt solder. -Take a stick of the latter, and just dip it in one of the soldering -solutions named, and rub it upon the work previously -brightened. The solder will adhere to both such pieces. -Now, while still hot, put them together and screw in a vice, -or keep them pinched in any way for a few minutes, and -you will find them perfectly secured. In making chucks -for the lathe, and in forming many parts of your models, -you will find it advantageous to work in this way; but, -notwithstanding, you will often require a light soldering-iron, -and sometimes also a blowpipe, which I shall likewise<span class="pagenum"><a name="Page_247" id="Page_247">[247]</a></span> -teach you to use, as also how to make a neat little fireplace -or furnace to stand on your bench by which to heat the iron.</p> - -<p>I must now suppose that you have carefully soldered the -dome to the middle of your boiler; and as the solder will -be underneath, the joint will be concealed even if (as is -likely) you should not have made a very neat piece of work. -Before you put on the bottom of the boiler, you will have -to make two holes in the top—one for the steam-pipe -three-eighths of an inch in diameter, the other for the -safety-valve also three-eighths—because this will require a -plug of brass to be soldered in, which plug will have a hole -drilled through it of a quarter of an inch diameter. These -may be punched through from the inside, or drilled; they are -easily made, but should be as round and even as possible.</p> - -<p>Take a piece of three-eighths-inch tubing, with a stop-cock -soldered into the middle of it. I shall suppose you -have bought this. It need not be over an inch in length -altogether; and you must put it through the hole in the top -of the boiler, and solder it round on the inside of the same. -The nearer you can get the stop-cock to the bottom of the -cylinder the better the engine will work, because the steam -will have to rise through whatever water is left in this pipe -from the jet used to cool the steam. You will see that it -cannot run off by the pipe C into the pump well, like that -which collects in the cylinder itself. In a real engine the -steam-tap was a flat plate which slid to and fro sideways,<span class="pagenum"><a name="Page_248" id="Page_248">[248]</a></span> -level with the bottom of the cylinder; but this you would -not make easily at present.</p> - -<p>The plug for the safety-valve you must turn out of a -little lump of brass. It must be about three-eighths of an -inch long; and you must drill a quarter-inch hole through -it, and countersink one end of the hole (that is, make it -wider and conical by turning a rosebit or larger drill round -in it a few times), to make a nice seat, as it is called, for the -valve itself, which need not be now attended to. Remember -you can buy at Bateman’s, or any model-maker’s in -London, beautiful safety-valves ready-made, as well as any -part of a model engine that you cannot make yourself; -and indeed it is so far a good plan at first that it saves you -from becoming tired and disgusted with your work, owing -to repeated failures. If you buy them, therefore, you must -do so before you make the holes above alluded to, but in -some respects it will be more to your advantage to try and -make all the details for yourself. I cannot call it making -an engine, if, like many, you buy all the parts and have -little left to do but screw them, or solder them, together. -Don’t do this, or you will never become a modeller.</p> - -<p>Your boiler from <i>c</i> to <i>a</i> is, in height, maybe 2 inches, -the dome 1½ or thereabout. This will slip inside the part -that you see in the drawing, and which I here sketch again -separately.<a name="FNanchor_3" id="FNanchor_3"></a><a href="#Footnote_3" class="fnanchor">[3]</a></p> - -<p><span class="pagenum"><a name="Page_249" id="Page_249">[249]</a></span></p> - -<div class="figcenter" style="width: 400px;" id="fig59"> -<img src="images/figure59.jpg" width="400" height="600" alt="" /> -<p class="caption">Fig. 59.</p> -</div> - -<p><span class="pagenum"><a name="Page_250" id="Page_250">[250]</a></span></p> - -<p>A is the boiler lifted out of B, the outer case or stand, -which you can make out of tin, and paint to imitate bricks. -It is almost a pity to waste sheet-brass upon it, because it -is not very important, its object being only to carry the -boiler. It is like D before being folded round and fastened -(not with solder, which would soon melt, but) by a double -fold of the joint, similar to that which you made round the -boiler itself, but turned over once more and hammered -down. The holes are punched with any round or square -punch with a flat end, and are intended to give more air to -the lamp C, which should have three wicks, or two at the -least, to keep up a good supply of steam. I have shown -the <i>flat</i> piece of tin with three legs only, which is as well -as if it were made with four; but you can please yourself in -this matter.</p> - -<p>The lamp I need hardly tell you how to make, for it is -easier than the boiler, being merely a round tin box, in the -top of which are soldered three little bits of brass tube for -the wicks, and a fourth for the oil to be poured in—the -latter being stopped with a cork.</p> - -<p>You should remember that no soldered work, like the inside -of the boiler, must come in contact with the heat of -the lamp, unless it has water about it, because if the water -should at any time entirely boil away, the boiler will leak -and be spoiled. A little care in this respect will insure -the preservation of a model engine for a long time; but<span class="pagenum"><a name="Page_251" id="Page_251">[251]</a></span> -boys <i>generally</i> destroy them quickly by careless treatment.</p> - -<p>Let us now turn our attention to the cylinder. Cut off -a piece of three-quarter-inch brass tube, 2½ inches in -length—you can do this with a three-square file—mount it -in the lathe by making a chuck like Fig. 59, E, of wood, -the flange of which is just able to go tightly into one end -of the tube. The other end will probably centre upon the -conical point of the back poppit, over which it will go -for only a certain distance. If your back centre will not -answer on account of its small size, you must make a -similar flange to go into the other end; but take care that -when the back centre is placed against it, it runs truly. -If the chuck is well made, it will do so. You can now -with any pointed tool turn off the ends of the tube quite -squarely to the side; but you should only waste one-quarter -of an inch altogether, leaving it 2¼ inches long. When -this is done, take it out of the lathe, and in place of it, -mount a disc of brass rather more than one-eighth of an -inch thick, or if you have none at hand, take an <i>old</i> half-penny -or penny piece, which is of copper, and lay it upon -the flat face of a wooden chuck, driving four nails round -its edge to hold it, and with a point-tool cut out neatly the -centre, of a size to fit inside your tube. You will scarcely, -however, effect this perfectly without further turning; so -take care to cut it too large; but before you cut it completely<span class="pagenum"><a name="Page_252" id="Page_252">[252]</a></span> -through, make the hole for the tube which you -soldered into the top of the boiler, which is three-eighths -diameter. This you can do beautifully in the lathe with a -pointed tool, or with a drill, centred against the point of -the back poppit, as I showed you before.</p> - -<p>Cut the disc quite out (too large, mind) and then turn a -spindle like G, mount the disc upon it as shown, by its -central hole, and turn the edge with a graver or flat tool, -such as is used for brass, until it will exactly fit the brass -tube. You can cut out round discs of one-eighth or one-fourth -sheet-brass by mounting any <i>square</i> piece on a -wooden face chuck, keeping it down by four nails or -screws, and then with a point-tool cutting a circle in it -until the disc falls out. You will often save time by so -doing. You now have a disc of brass or copper with a hole -three-eighths of an inch wide in it; and as the disc is -three-fourths of an inch in diameter (<i>i.e.</i>, six-eighths), you -will have three-eighths remaining, or three-sixteenths, each -way on the diameter between the edge of the hole and that -of the disc. This will just give room for the two small -holes required, one on each side of the central one, for the -pipes from the cold-water cistern and to the well below the -pump. These must both be of brass; and the first should -be turned up and end in a jet, like a blowpipe, so as to -make the water rise in a spray under the piston; the other -should be as long as can be conveniently arranged.</p> - -<p><span class="pagenum"><a name="Page_253" id="Page_253">[253]</a></span></p> - -<p>The bottom of the cold-water cistern is drawn a little -above the top of the cylinder, which is 2¼ inches high. A -jet would theoretically rise in the cylinder to nearly the -height of the level of water in the cistern; but with a small -pipe, and other drawbacks inseparable from a model, you -must not reckon on more than about half that height, -which should be sufficient to condense the steam. The -piston had better be nicely fitted, but not packed. You -cut a disc of brass as before, drill the hole for the piston, -make a spindle, or put in the piston-rod, and centre this as -a spindle, which is the <i>best</i> plan, and then with a flat brass -tool turn the piston accurately to fit the tube. Or, if you -think it easier, or wish to fasten the piston with a nut, as -drawn, you can, if you like, turn it on a separate spindle; -and thirdly, you may tap the hole in the piston, and screw -the end of the piston-rod. The great thing to attend to is, -to turn the edge of the piston square to the sides.</p> - -<p>For the piston-rod, a steel knitting needle or piece of -straight iron wire will do very well; but it will have to be -flattened at the upper end, or screwed into a little piece of -brass, which must be sawn across to make a fork by which -the chain can be attached which goes over the beam. Do -not solder the cistern pipes in just yet, but go on to other -parts.</p> - -<p>The cistern itself can be made out of any tin box. A -seidlitz-powder box will answer well, or you can make one<span class="pagenum"><a name="Page_254" id="Page_254">[254]</a></span> -about that size, say 4 inches long, 2½ wide, and 2 deep. -The cistern for the pump will, of course, require to be the -same size or a little larger; it may stand on legs or be -fastened to the bed-plate direct.</p> - -<p>This bed-plate is shown below the picture of the engine. -It is merely an oblong plate of iron one-sixteenth inch thick, -or in this particular engine may be of tin neatly fastened to -a half-inch mahogany board, which will keep all firm. The -white places show the position of the boiler and of the -pump cistern, the inner rounds indicating the lamp, and -pump, and cylinder. The square is merely made to show -a boiler of that shape, which some prefer;—it is not so -good as a cylindrical one.</p> - -<p>Whenever you have to make an engine, you should draw -upon the bed-plate the position of each part, as I have done -here, because it will serve you as a guide for measurement -of the several pieces. The four small circles at S S show -the positions of the legs of the support C, which carries -the beam. In the drawing only two are given, but there -would be a similar triangular frame upon this side. This -may be made very well of stout brass wire, but in a bought -engine it would be a casting of brass, painted or filed -bright.</p> - -<p>The beam itself should be of mahogany, 6 inches long, -half an inch wide (on the <i>side</i>), and a quarter of an inch -thick. The curved pieces you will turn as a ring 3 inches<span class="pagenum"><a name="Page_255" id="Page_255">[255]</a></span> -diameter with a square groove cut in the edge for the -chain. You can then saw into four, and use two of these, -morticing the strip of mahogany neatly into them. Then -finish with four brass wires, as shown, which will keep the -curved ends stiff and give a finished appearance. The pin -in the centre should be also of brass, as a few bright bars -and studs of this metal upon the mahogany give a handsome -look to the engine.</p> - -<p>The pump will be of brass tube, made like the cylinder, -but the bucket may be of boxwood, and so may the lower -valve, each being merely a disc with a hole in it, and a -leather flap to rise upwards. The bucket, however, should -have a groove turned in its edge, to receive a ring of india-rubber, -or a light packing of tow. The end of the pump-rod -must be split to make a fork like Y, to allow the valve -to rise. You can get just such a fork ready to hand out of -an umbrella, if you can find an old one; if not, and you -cannot split the wire, make the rod rather stouter, and -bend it, as shown, so as to form only one side of a fork, -which will probably answer the same purpose in so light a -pump.</p> - -<p>The valve in both of these may be made of a flap of -leather—bookbinder’s calf, or something not too thick—and -it may be fastened at one edge by any cement that -will not be affected by water, or by a small pin,—cut off -the head of a pin with half an inch of its shank, and point<span class="pagenum"><a name="Page_256" id="Page_256">[256]</a></span> -it up to form a small tack. If the valve-box is of boxwood, -you must drill a hole;—you may make it, if preferred, -of softer wood.</p> - -<p>There is no support shown in the drawing for the cold-water -cistern; but you must stand it on four stout wires, or -on a wooden (mahogany) frame, which can be attached to -the bed-plate. As this last is always of some importance, -I shall add it again in this place (Fig. 60), to a scale of -three-quarters of an inch to the foot, showing the position -of each part.</p> - -<p><span class="pagenum"><a name="Page_257" id="Page_257">[257]</a></span></p> - -<div class="figcenter" style="width: 600px;" id="fig60"> -<img src="images/figure60.jpg" width="600" height="325" alt="" /> -<p class="caption">Fig. 60.</p> -</div> - -<p>Always begin with a centre line and take each measure -from it, and draw another across for the same purpose, at -right angles to the first. You will quickly see the use of -this. We draw two lines as described A, B, C, D, crossing -in <i>o</i>. The longest is the centre line of beam, cylinder, -and pump. The beam is to be 6 inches long to the outside -of the middle of each arc, whence the chain is to hang. -We, therefore, from the centre point, set off 3 inches each -way. At the exact 3 inches will be the centres of the -cylinder and pump;—set these off, therefore, on the plan. -The end of the tank we must have near the cylinder, -because we have to bring a pipe from it into the bottom -of the cylinder. Set off, therefore, the end of the tank 2½ -inches—<i>i.e.</i>, 1¼ on each side of the central line, and draw it -4 inches in length. N shows the position of the pipe close -to the end and on the line. The centre of the boiler is the<span class="pagenum"><a name="Page_258" id="Page_258">[258]</a></span> -same as that of the cylinder, so we draw a circle round it -with a radius of 1½ inches, which gives us the 3-inch -circle of the boiler. Then we may set off equal distances, -N, N, for the extremities of the legs of the frame which -is to support the beam, and we complete our plan. M is -the waste pipe, and K is the opening for the water to flow -into the tank. We now find, therefore, that the bed-plate -must be 13 inches long and 6 inches wide to take the -engine of the proposed size, and we may, of course, extend -this a little, if thought desirable. Mark off on the bed all -the lines of the plan as here given, and always start any -measurement from one of the two foundation lines, or else, -if you make one false measure, you will carry it on, probably -increasing the amount of error at every fresh -measurement. Let this be with you a rule without exception. -It is plain that if you work all parts of your -engine to size, you can set it up on the marked bed-plate -with perfect accuracy.</p> - -<p>The description I have given will not only enable you to -make a Newcomen engine with very little difficulty, but -will give you an insight generally into this kind of work; -and you will learn, too, a practical lesson in soldering, turning, -and fitting. I must, nevertheless, help you a little in -putting your work together.</p> - -<p>You had better begin by soldering into the bottom of the -cylinder the end of the <i>steam-pipe</i>, which you have already<span class="pagenum"><a name="Page_259" id="Page_259">[259]</a></span> -fixed upright in the middle of the dome of the boiler, taking -care that it stands squarely across the pipe, or your cylinder -will not be upright. Then place the boiler in position, and -you may fix it by turning out slightly the ends of the legs, -and putting a tack through, or screwing, if the bed-plate is -of iron,—or with help of Baker’s fluid you can solder; but -this is hardly safe work, and you had better have a wooden -plate, covered with tin, and tack down the legs. I have -drawn you a circular lamp, and given three and four legs to -the boiler-stand; but take care that you so arrange size -of lamp and openings of the stand as to enable you to -withdraw the former for trimming and filling. Now fit in -the two small pipes, previously bent as required. To bend -them, if hard soldered or brazed, fill with melted lead, and -then bend; after which melt out the lead again. If soft -soldered, you must fill with a more fusible metal. There is -a composition called “fusible metal,” very convenient for -this work, and well worth making, because you will often -need to bend small pipes into various forms. Melt -zinc, 1 oz.; bismuth and lead, of each the same quantity—this -will melt in <i>hot</i> water; 8 parts bismuth, 5 lead, -and 3 tin, will melt in <i>boiling</i> water. You can buy -these at any <i>operative</i> chemist’s, either mixed, ready -for use, or separately. Rosin and sand are also used -for bending tin pipes, the sole object being so to fill -them that they will become like a solid strip of metal, and<span class="pagenum"><a name="Page_260" id="Page_260">[260]</a></span> -thus bend slowly and equally, with rounded and not sharp -angles.</p> - -<p>Pass the two pipes through from beneath the bottom of -the cylinder, and solder them on the upper side of it, so -that when the cylinder itself is added these two joints will -not be visible. Then set up the cold-water cistern; block -it up with anything you like so as to keep it in position, -and, inserting the pipe from below, solder this also from -above, <i>i.e.</i>, on the <i>inside</i> of the cistern. Now, arrange the -frame that is to support it, either stout wire or wood, and -set it up so as finally to secure it in its place. Now, you -had better set up the pump cistern, so as to secure the other -small pipe in position, and prevent it from becoming displaced -by any accidental blow. Fix this cistern therefore -also, but leave the cover off for the present, that you may -be able to solder the small pipe <i>inside</i> it.</p> - -<p>You will now, at all events, have secured the position of -the most important parts, and you may drop the cylinder -into place, and solder this also round the bottom. This -would be facilitated by turning a slight rebate, Fig. 60, S, -round the disc which forms the bottom of the cylinder, so -that the smaller part of it will just fit inside it; but you -will be able to manage it without. Let the cylinder project -a very little beyond the bottom, just to allow a kind of -corner for the solder to run in; it will not show when all -is fixed. Do this as quickly as you can, so as not to melt<span class="pagenum"><a name="Page_261" id="Page_261">[261]</a></span> -off the solder round the small pipes. Now, make the pair -of A-shaped supports for the beam. Measure the height of -your cylinder top, above the bed-plate, and allow about -another inch, and you will get the perpendicular height to -the axis of the beam. Allow 3 inches more for each side, -that is, in all for <i>each</i> side, 3 inches longer than if it was to -be perpendicular instead of spreading. Take enough brass -wire, about as thick as a small quill, to make two such legs. -Bend it in the middle, like T, Fig. 60, and flatten the bent -part by hammering, so as to allow you to drill a hole to -take the pivot on which the beam is to oscillate. If you -like to flatten all of it, and then touch it up with a file, -so as to get quite straight edges, it will look much more -handsome. Make two such pieces exactly alike, and, at -distances alike in each, put cross-bars. File a little way -into each, making square, flat notches, which will just take -two flattened bars of the same wire; heat them, and solder -very neatly, so that no solder appears on the outside; file -all flat and true. In this way you can make almost as neat -supports as if they were of cast brass, and you are saved all -the trouble of making patterns. By and by, nevertheless, -you must do better.</p> - -<p>As I have directed you in this instance to put a wooden -bed-plate to your engine, you may point the ends of the -wires, and, making holes sloping at the same angle in the -wooden stand, drive the wires into them. You have an<span class="pagenum"><a name="Page_262" id="Page_262">[262]</a></span> -advantage here, inasmuch as you can raise or lower your -stand until the position of the beam comes exactly right, -and you find the ends drop over the centre of the cylinder -and pump-barrel as it ought to do. When this is the case, -you can cut off any wire that projects below the stand and -file it level, for it will not be likely to need more secure -fixing. The pump may now be soldered into the cover of -the cistern (before the cover itself is fastened on), and a -hole must be then cut to receive the water that will flow -from the spout, and then the cover can be fitted on. There -is no need to solder it, if it is made to <i>fit</i> over-tightly; and -you may wish, perhaps, to get at the lower valve of the -pump now and then.</p> - -<p>The only thing left to do is to arrange the safety-valve -of the boiler, which is in many cases the place through -which the water is poured to charge it. In this engine it -is, however, plain that you can fill the boiler by turning -both the taps at the same time. A little will run off by the -waste-pipe, but not enough to signify, because the tube -below the cylinder is so much the larger of the two. The -safety-valve is a little bit of brass turned conical to fit the -“seat,” made by counter-sinking the hole. It is shown at -K, Fig. 59, N being the seat, O P the dome of the boiler, -and close to O is the gauge-tap for ascertaining the height -of water in the boiler. L M is a lever of flattened wire, -pivoted to turn on a pin at L,—L O being an upright wire<span class="pagenum"><a name="Page_263" id="Page_263">[263]</a></span> -soldered to the boiler. A notch is filed across the top of -the valve, on which the lever, L M, rests. The weight is -at M. One, as large as a big pea, hung at the end of a -lever 2 inches long, the valve at half an inch from the -other end, will probably suffice for this engine.</p> - -<div class="figcenter" style="width: 275px;"> -<img src="images/footer4.jpg" width="275" height="125" alt="" /> -</div> - -<hr /> - -<p><span class="pagenum"><a name="Page_264" id="Page_264">[264]</a></span></p> - -<div class="figcenter" style="width: 500px;"> -<img src="images/header2.jpg" width="500" height="110" alt="" /> -</div> - -<h2 id="CHAPTER_XIII"><span class="smcap">Chapter XIII.</span></h2> - -<h3>WATT’S ENGINE.</h3> - -<div> -<img class="dropcap" src="images/dropcap-i.jpg" width="100" height="120" alt="" /> -</div> - -<p class="dropcap">I have already told you that Watt suggested -the use of steam alternately on each side of the -piston; and carried it out by closing the top of -the cylinder, and allowing the rod of the piston -to pass through a stuffing-box or gland. I now have to -explain to you how this alternate admission of the steam -may be effected.</p> - -<p>You evidently require first an opening at the top and -bottom of the cylinder, communicating with the boiler, one -only being open at a time; but in this case, where is the -steam to escape that was on one side of the piston when -the opposite side was being acted upon? It must go -somewhere, but evidently must not return to the boiler. -Hence, some method has to be contrived by which, when -one end of the cylinder is open to the boiler, the other -may be open to the air or to the condenser (in which the -steam is cooled under Watt’s plan). Fig. 61 will, I think, -render clear one or two of these arrangements.</p> - -<p><span class="pagenum"><a name="Page_265" id="Page_265">[265]</a></span></p> - -<div class="figcenter" style="width: 400px;" id="fig61"> -<img src="images/figure61.jpg" width="400" height="600" alt="" /> -<p class="caption">Fig. 61.</p> -</div> - -<p><span class="pagenum"><a name="Page_266" id="Page_266">[266]</a></span></p> - -<p>The first is the four-way cock, a very simple contrivance, -easily and frequently used in models. You must -first understand how a common water or beer tap is made. -Fig. 61, A, represents one in section, turned so as to open -the passage along the pipe to which it is attached; C is the -pipe in which is the tap, a conical tube of brass set -upright, and with a hole right and left made through it, -fixed into a short horizontal tube (generally cast with it -in one piece). Into this fits very exactly the conical plug -B, also with a hole through it sideways. When this is put -into place, no water or other liquid can pass, unless the -hole in the plug is in the same direction with the hollow -tube forming an open passage. If a key is put on the -square part of the plug, and it is turned half round, the -passage through the pipe will be closed. A steam tap -would be made in a similar manner, if its only office were -to open and close a passage in a tube. But we now want -two passages closed and two opened, and then the alternate -pair closed and opened. This is cleverly effected by a four-way -cock.</p> - -<p>At D is shown a section of the steam cylinder and piston, -with the stuffing-box and all complete. A pipe enters this -at the top and bottom, and another crosses it in the middle, -making four passages. Shaded black is the four-way cock,<span class="pagenum"><a name="Page_267" id="Page_267">[267]</a></span> -the white places showing the open channels through the -plug. When this plug stands as at D, steam can pass from -the boiler to the top of the cylinder only, above the piston, -which it drives downward; the steam below the piston -escapes through the other open-curved channel into the air, -or to the condenser. Just as the piston reaches the bottom -of the cylinder, the tap is turned, and the passage stands -as seen at E. Steam now passes to the bottom below the -piston, driving it upward, and the steam above it, which -has done its work, passes outward through the other open -channel of the tap.</p> - -<p>You must understand that when Newcomen first set up -his engine, a man had to turn the taps at the proper -moment; and it is said that one Humphrey Potter, a boy, -being left in charge, and getting tired of this work, first -devised means to make the engine itself do this, by connecting -strings tied to the handles of the taps to the beam -that moved up and down above his head. Beighton and -others improved on this, and very soon it became unnecessary -for the attendant to do anything but keep up a good -fire, and attend to the quantity of water in the boiler, and -the pressure of the steam.</p> - -<p>In the model I gave you of Newcomen’s engine, I purposely -left the taps to be moved by hand; but F of the -present figure shows how, by bringing them near together, -and adding cogged wheels or pulleys, you would make one<span class="pagenum"><a name="Page_268" id="Page_268">[268]</a></span> -handle answer for both; and I shall leave you to devise an -easy method of making the engine work this one handle for -itself. When Watt made his first engine, therefore, this -work had been already done, and he only had to improve -upon it, and to make it work more accurately to suit the -engine designed by himself.</p> - -<p>If you should chance to pay a visit to the Museum at -South Kensington, you may see, I believe, Watt’s original -engine, if not Newcomen’s. The cylinders are so large and -cumbrous, that the wonder is they were ever bored by the -inefficient means then in use; and the beam is a most -unwieldy mass of timber and iron, that looks as if no -power of steam could ever have made it oscillate. Yet it -was in its day a successful engine, the wonder of the age; -and did good work for its inventor and purchaser. I -strongly advise my readers to try and visit Kensington, -for there are many interesting models there, besides engines -and appliances of older days. They will thus learn what -rapid progress has been made since the days of Savery, -Newcomen, and Watt; not only in the improvement of the -arrangement of the parts, but in the workmanship, which -last is mainly due to the invention of the slide-rest and -planing-machine.</p> - -<p>We must now return to the double-acting or real steam -engine, and consider a second means whereby the steam -can be alternately admitted and exhausted.</p> - -<p><span class="pagenum"><a name="Page_269" id="Page_269">[269]</a></span></p> - -<p>The four-way cock, already explained, was found to wear -very considerably in practice, and hence work loose, and a -new contrivance, called the slide-valve, soon took its place. -Of this there are two patterns, the long D-valve and the -short one, which latter is used for locomotives. There is -also a form called a tappet-valve, often used for large -stationary engines, but which is noisy and subject to rapid -wear. I shall describe the long D first, in the form in -which it would be most easily made for a model engine.</p> - -<p>The two ports by which steam passes to the cylinder are -shown at <i>d</i>, <i>e</i>, of H, Fig. 61. C is the passage to the -boiler, K is that to the condenser. These are openings in -a tube smoothly bored within, and having at the top a -stuffing-box like that on the cylinder. Within this tube -works an inner one, <i>b</i>, having rings or projections at the -ends fitting perfectly, and which are packed with india-rubber, -hemp (or, in modern days, with metal), to make -a close fit. In a model, two bosses of brass, K, soldered -on the tube and then turned, make the best packing. -These packed portions of the inner tube form the stoppers -to the steam ports, <i>e e</i>, alternately, at the top and bottom. -The upper part of the inner tube has a cross arm, 3, -affixed, from the centre of which rises the valve-rod by -which it is moved up and down. In the position 1, the -steam can pass from <i>c</i> round the tube to <i>d</i>, and thence to -the top of the cylinder to which <i>d</i> is attached. The exhaust<span class="pagenum"><a name="Page_270" id="Page_270">[270]</a></span> -steam passes from <i>e</i> below the piston by <i>k</i> to the condenser. -In the second position, 2, the steam is evidently shut off -from <i>d</i>, but can pass out at <i>e e</i> below the cylinder, while -the communication is still open to the condenser from <i>d</i>, -through the middle of the tube to K. This is a very good -form of valve, because the exhaust is always open, and the -motion is smooth and equal.</p> - -<p><span class="pagenum"><a name="Page_271" id="Page_271">[271]</a></span></p> - -<div class="figcenter" style="width: 350px;" id="fig62"> -<img src="images/figure62.jpg" width="350" height="600" alt="" /> -<p class="caption">Fig. 62.</p> -</div> - -<p>There are many modifications of the long D-valve, but -the principle of all is the same; I shall therefore describe -the short slide-valve which is nearly always used in the -models which are purchased at the shops. This, too, is -the usual form of valve in locomotives, traction-engines, -and the majority of those in use for agricultural and -similar purposes. A, Fig. 62, is the cylinder as before -in section with piston. A thick piece is cast with the -cylinder, on one side of it, having steam ports also cast in -it, which are here left white. The two as before go to the -top and bottom of the cylinder, and have no communication -with the central one, which is bored straight into -the boss, and generally is turned at right angles and connected -with the condenser, or with a pipe opening into the -chimney of the engine to increase the draught by means of -the jets of steam, as is the case always in locomotives, or into -the air, which is less usual. Seen from behind, these ports -are like B, being cast and cut rectangular; and the face, B, -is planed quite level, which is absolutely necessary to the<span class="pagenum"><a name="Page_272" id="Page_272">[272]</a></span> -proper action of the slide-valve which has to work upon -it. This valve is a box of iron, C, with a wide flange or -rim, this flange being of sufficient width to close either -port. If this valve is placed as it stands when the engine -is at rest, <i>b</i> covers the upper steam port, and <i>a</i> the lower; -while the exhaust or middle port is open to the hollow part -of the box. Now, if we slide the valve downwards until the -upper port is open, the other two will be in communication, -being united by being both together in the inside of this -box or valve. Suppose the valve then cased in, and that -steam is admitted from the boiler into the case, it is -evident that such steam could freely pass to the top of -the cylinder above the piston to force it downwards, while -that which was below would escape by the lower port into -the box, and thence pass to the condenser. If, instead of -pushing down the valve, we had drawn it upwards, the -lower port would have been opened, and the upper and -middle would have been brought into communication inside -the valve, and the contrary effect would have been -produced upon the piston.</p> - -<p>This is the arrangement adopted, and which will be -clearly understood from the following sectional drawing, -D. <i>a</i>, <i>a</i>, is the thick casting upon the cylinder, with the -upper and lower steam ports, which end towards the middle -of the cylinder, with the third port lying between; then <i>b</i> -is a section of the valve, in such a position that the flange<span class="pagenum"><a name="Page_273" id="Page_273">[273]</a></span> -of it no longer covers the lower steam port, while the other -two are open together on the inside of the valve. The -latter is cased in by the valve-box, <i>e e</i>, in the back of -which is the steam pipe <i>f</i> coming from the boiler. The -valve-rod, which is moved by the engine, passes at <i>o</i> -through a stuffing-box. It is evidently necessary that -this slide-valve should fit, and work very smoothly and -correctly against the face of the ports, so as not to allow -any escape of the steam. It is not, however, packed in -any way at the back (although springs have been sometimes -added), because, as the back is subjected to the full -pressure of the steam from the boiler, this keeps it quite -close to its seat. The rod, however, by which it is worked, -might prevent this close contact of the two surfaces if it -was screwed into the valve; it is therefore made with a -cross, E, at the end, which falls into a notch in a boss -cast upon the back of the valve as seen at F. This allows -a certain degree of play in one direction, and permits the -steam to press it close even after it has become worn by -use.</p> - -<p>You will, I think, now clearly understand how steam -can be admitted alternately to the top and bottom of a -cylinder, and how the exhausted steam that has done its -work escapes. I must therefore now tell you how the rod -of the slide-valve is moved up and down by the engine, -but to do this, I must draw such engine complete.</p> - -<p><span class="pagenum"><a name="Page_274" id="Page_274">[274]</a></span></p> - -<div class="figcenter" style="width: 450px;" id="fig63"> -<img src="images/figure63.jpg" width="450" height="600" alt="" /> -<p class="caption">Fig. 63.</p> -</div> - -<p><span class="pagenum"><a name="Page_275" id="Page_275">[275]</a></span></p> - -<p>The cylinder, A, is screwed down on its side upon the -bed-plate, R R, out of which are cut two holes, one for -the fly-wheel, P, of which part only appears for want of -space, the other for the crank, L, on the end of the axle, -M M, running through bearings, N N. The slide-valve-box -is at B, C being the steam-pipe from the boiler. The piston-rod -has necessarily to move only in a straight line in the -direction of its length, but the crank which it has to work -to turn the fly-wheel must needs move round in a circle. -Hence, a poker-and-tongs joint, F O F, is arranged. -The connecting-rod, H, which is attached to the crank by -brasses at K, divides or is attached to a forked piece, at -the lower end of which are a pair of bearings or brasses, -F F. The piston-rod carries the piece O, the cross-bar of -which is turned, being, in fact, the pin which passes into -these bearings at F F. This forms, therefore, a hinge-joint -at this place, so that although the piston-rod cannot -leave the right line, and can only slide in the guide, E, -the rod, H, has an up-and-down motion upon this hinge, -allowing the revolution of the crank-pin to take place. D -is the valve-rod, in which is a hinge at S, which suffices for -the slight movement required in the rod, as it rises and -falls by the action of the eccentric, T, the motion and effect -of which I now have to explain.</p> - -<p>V is a round disc of metal with a recess on its edge, so -that it is like an ordinary pulley, but large in proportion to<span class="pagenum"><a name="Page_276" id="Page_276">[276]</a></span> -its thickness. A hole for the main crank axle, to which it -has to be firmly keyed, is made through it, but <i>not in its -centre</i> (hence its name, eccentric—out of the centre). As -the axle revolves, it is evident that this disc revolving with -it will carry any point, Y, of its surface round in a circle; -the centre of which is on the central line or axis of the -crank-shaft. I have drawn such circle as described by the -point Y, farthest from the axis; but any and all points -describe larger or lesser circles round the same centre. -The point Y may, therefore, be considered as the centre of -a crank-pin; and the eccentric might, so far as its effects -are concerned, be replaced by a crank. Now, if you turn -the fly-wheel of your lathe by hand, the crank will revolve, -but the treadle will rise and fall only in a straight line; -and you will presently see how the eccentric, in its revolution, -gives just such a to-and-fro motion to the rod D, -and consequently also to the slide-valve, which it has to -move.</p> - -<p>Round the disc V, closely encircling it, is a flat ring, -shown separately at X, with a rod, W, attached to and part -of it. This ring is generally made in separate halves, -united by bolts passing through projecting lugs or ears. -The ring also fits into the groove turned on the edge of the -disc V, so that it cannot slip off sideways. This outer ring -is turned quite smooth and true on the inside, so that the -eccentric disc can revolve within it. In doing so, it is<span class="pagenum"><a name="Page_277" id="Page_277">[277]</a></span> -plain that the whole ring will rise and fall, and that the -rod W will move up and down, or to and fro, like the -treadle of the lathe, thereby giving motion to the valve-rod, -which is a continuation of the rod W. As the upper -end, however, of this rod has an oscillating, or up-and-down -motion, this is imparted, in a certain degree, to its -other end, at the farthest distance from the eccentric; and -hence the necessity for a hinged joint at S, to prevent the -valve-rod from partaking of this movement. It is, however, -very slight, so that the rod of the valve is not often -made to pass through guides like the piston. The whole -movement of the valve-rod is very limited, its traverse only -being required to be sufficient to shift the valve the width -of one of its ports at each stroke. The length of <i>stroke</i> or -traverse which can be obtained by the eccentric is always -equal to twice the distance between its real centre, and that -on which it turns, which will always be a guide to you in -making an engine.</p> - -<div class="figcenter" style="width: 400px;" id="fig64"> -<img src="images/figure64.jpg" width="400" height="500" alt="" /> -<p class="caption">Fig. 64.</p> -</div> - -<p>The drawing here described is a plan, <i>i.e.</i>, a drawing -viewed directly from above; therefore I cannot show you -the perspective view of the parts, which are, indeed, in -many cases only suggested by the shading. I have, therefore, -added a second drawing of the several details. This -engine is, in construction, the simplest that can be devised -with a slide-valve, there being no additions beyond what -are absolutely necessary to make it work; the exhaust-port<span class="pagenum"><a name="Page_278" id="Page_278">[278]</a></span> -is below, opposite to the letter B on the valve-box. A, -Fig. 64, is the forked connecting-rod, marked H in the -previous drawing. This is cast with forked ends, <i>x</i>, and <i>x</i><span class="pagenum"><a name="Page_279" id="Page_279">[279]</a></span> -Y (the latter being F F of Fig. 63). These ends receive -brasses in the following way, the end <i>x</i> being represented -on a larger scale at B, with such brasses in place; of these -there are two shaped like D. One of these lies in the fork -of the connecting-rod end. A second similar one lies in -the strap of iron C, which reaches beyond the first. A -cotter or key, which is, in fact, a wedge of iron, is then -passed through a slot in the strap, and a similar one in the -rod; and being driven home, draws the two brasses tightly -together, causing them to embrace the crank-pin, L, Fig. -63, or any similar bearing. All shafts that revolve in -bearings are made to pass through brasses, and whenever -these occur at the end of a rod, they are fitted as here -described. E is another bearing of cast-iron, also fitted with -brasses; but in a case like this, a plate lies on the upper one, -and is screwed down by bolts and nuts as required. This -bearing would do very well at E, Fig. 63, as a guide for -the piston-rod; but in models such guide is commonly -made without brasses, like F or G of the present drawing.</p> - -<p>At H, I have shown the part F O F of the drawing 63. -The middle is of brass or iron; if of the former, <i>g g</i> must -be separate, as these gudgeons would not be substantial -enough, unless of iron or steel. It is essential that K L, -the piston-rod, should be in one right line; but, if this is -attended to, they need not necessarily be one piece; and -frequently the piston-rod, L, is fixed into one end of the<span class="pagenum"><a name="Page_280" id="Page_280">[280]</a></span> -central casting, and another rod, K, is screwed into the -other. In a model, the piston-rod should pass quite -through, and <i>g g</i> should be two separate gudgeons screwed -in, and then turned together in the lathe, to insure their -being exactly in one line. These go into the brasses in -the forked ends of the connecting-rod, to form a hinge at -that part, as will be understood by a reference to Fig. 63.</p> - -<p>At M, I have shown another simple eccentric and rod, -which is less trouble to make in a model than the other. -In this the ring is made in one piece, with a round rod -screwing into it. The disc has a slight groove turned in -its edge, and a small screw, P, passes through the ring and -falls into this groove. This suffices to prevent the ring -from falling off sideways, and of course is not screwed -down so tight as to prevent the disc from revolving. This -is a very easy way to fit the eccentric, and is generally -followed in small engines. The lattice eccentric rod is -nearly always used in large beam engines.</p> - -<p>I do not think the reader will now have any difficulty in -understanding the precise arrangement of the various parts -in the simple horizontal engine of which I have given a -sketch. It is a neat and convenient form, easily arranged -as a model, and I shall proceed at once to the practical -work of constructing this, and engines in general, presupposing -a knowledge of the use of the lathe, and of the few -tools required.</p> - -<hr /> - -<p><span class="pagenum"><a name="Page_281" id="Page_281">[281]</a></span></p> - -<div class="figcenter" style="width: 500px;"> -<img src="images/header2.jpg" width="500" height="110" alt="" /> -</div> - -<h2 id="CHAPTER_XIV"><span class="smcap">Chapter XIV.</span></h2> - -<h3>HOW TO MAKE AN ENGINE.</h3> - -<div> -<img class="dropcap" src="images/dropcap-t.jpg" width="100" height="120" alt="" /> -</div> - -<p class="dropcap">The very first mechanical work of difficulty, but of -pre-eminent importance, in making an engine, -is boring the cylinder, that is, if the same is a -casting, and not a piece of tube ready made and -smooth on the inside. This is, properly speaking, lathe -work, yet may be done in a different way. Suppose you -have bought your entire set of castings, which is the best -way, and that the cylinder is half an inch diameter inside, -which is a manageable size to work upon. Get a half-inch -rosebit, which is very like the countersinks sold with the -carpenter’s brace and bits. Mount it in the lathe in a -chuck, A, Fig. 65. Unscrew the point of the back poppit, -and slip over the spindle a boring-flange, B, which is -merely a flat plate like a surface chuck, only the socket is -not screwed but bored out, generally large enough to slip -over the spindle. Sometimes there is, however, a screw at<span class="pagenum"><a name="Page_282" id="Page_282">[282]</a></span> -the back, to screw <i>into</i> the spindle, the same as the points -or centres. On the face of this lay a piece of board of equal -thickness, but it is as well if not planed, as its object is -partly to prevent the cylinder from slipping about during -the operation, as it is sometimes inclined to do upon the -smooth metal flange, and partly to prevent the borer or -rosebit from coming in contact with the flange when it -has passed through the cylinder. Grasp the latter in the -left hand, and you can easily prevent it from revolving with -the drill, which will go through rapidly, and leave the hole -beautifully finished and quite true from end to end,—indeed, -I have bored iron also, rapidly and with great ease, -with this tool.</p> - -<div class="figcenter" style="width: 400px;" id="fig65"> -<img src="images/figure65.jpg" width="400" height="600" alt="" /> -<p class="caption">Fig. 65.</p> -</div> - -<p><span class="pagenum"><a name="Page_283" id="Page_283">[283]</a></span></p> - -<p>It is absolutely necessary, remember, that this hole bored -in the cylinder should be at right angles to the <i>ends</i> of the -same, and to secure this you must now make use of it to -mount the cylinder in the lathe to turn these ends or -flanges. I will show you a simple and easy way to do this. -C is a bar of iron or steel, preferably of the latter, about 6 -inches long, and three-eighths diameter, filed into six sides. -It is a good plan to have three or four sizes of such bars, -with centre holes drilled carefully into each end, so that -you can mount them with a carrier-chuck, as you would if -you were going to turn them. Taking one of about the -size named, mount upon it a piece of wood, and turn this -down until your cylinder will just go tightly upon it.<span class="pagenum"><a name="Page_284" id="Page_284">[284]</a></span> -Being a six-sided bar, it is easy to mount the wood upon it -by boring the latter with a gimlet and then driving the bar -into it. It will hold tightly, and not turn round upon the -metal. The cylinder being fixed in this way, you must -turn the two flanges with a graver if the cylinder is of iron, -but with a flat tool or the four-sided brass tool if of the -latter metal; and also turn the edges of the flanges. The -rest of the cylinder will be left in the rough, and may be -painted green or black. I should advise you always to bore -the cylinder first when possible, and then to mount it as -described and turn it on the ends, which are thus sure to -be correctly at right angles to the bore. Some cylinders, -however, especially short ones, may be squared up first, and -then mounted on a face-plate and bored. Unless, however, -you have either a grip-chuck, which is self-centring, or -some clamps properly constructed for this particular work, -you will find the first method the easiest, especially for -small light work.</p> - -<p>You should now make the ports for steam and exhaust. -Mark them upon the flat part of the casting, after you -have filed this as level as you can, and do not mark them -so long as not to leave you room beyond the <i>ends</i> of the -ports for the steam-box or case which has to be placed here. -The upper and lower ports are to be the same size, but the -middle one may be a trifle larger with advantage. In -larger engines these are cast in the metal, and have only<span class="pagenum"><a name="Page_285" id="Page_285">[285]</a></span> -to be trimmed and faced; but in the small models you have -to drill them out in the boss cast on the cylinder. Drill -down from the top, as shown at D by the dotted lines, but -take great care not to go farther than the <i>outer</i> ports, which -are to be therefore first made, so that you can tell when the -drill has gone far enough. If you pierce the middle port -from either end, the cylinder is spoiled. To cut the middle -one, you merely drill a hole straight in towards the cylinder, -and meet it by another drilled from the side, into which the -pipe for the exhaust is to be screwed. You also drill -straight through into the cylinder at <i>a b</i>, and you then -plug the end of <i>f</i>, and that at the other end of the cylinder. -Your port faces, however, are generally oblong, and not -round. Make a row of holes with the drill, and then, with -a little narrow steel chisel and light hammer, chip out -the superfluous metal, and finish with a small file. You -can always make narrow channels with squared sides by -thus drilling two or more holes, and throwing them into -one with a file; but in reality, for these small engines, it is -very little matter whether the ports are round in section or -square.</p> - -<p>The bottom and top of the cylinder demand our next -attention. E and F show these. They are easily and instantly -mounted in a self-centring chuck, but can be held -very well in one of wood carefully bored with a recess of the -right size and depth. You must here, nevertheless, be very<span class="pagenum"><a name="Page_286" id="Page_286">[286]</a></span> -particular, else you will get your work untrue at this point, -and then your piston-rod will stand awry, and all your -subsequent fitting will be badly done. I therefore give you -at G a section of the chuck bored to take the cover truly. -Recess the part down to the line <i>a b</i>, to fit the cover exactly, -taking care to level very carefully the bottom of the recess. -Below this cut a deeper hole, to allow the flange in which -the stuffing-box will be to go into it. It need not, however, -<i>fit</i> the flange. The rough casting will hold very well -in a chuck like this, even if it is of iron. You now carefully -face the bottom of the cover, and turn the slight -flange exactly to fit into the cylinder; then reverse it in the -chuck, so as to get the stuffing-box outside; and in doing -so, take the greatest care that it beds flat upon the bottom -of the chuck. Turn off level the top of the flange first at <i>x</i> -of fig. E, and then place a drill with its point against the -middle of this, and its other end (with a little hole -punched in it to keep it steady) against the back poppit -centre, and carefully drill a hole down to the level of <i>c</i>, -large enough to admit the gland of the stuffing-box or nearly -so; but remember that you must not go too far, because -the rest of the hole must only just allow the piston-rod to -go through it. Therefore, after you have drilled about -three-fourths of the distance, replace this drill by a smaller -one, and with it bore quite through. The advantage of beginning -in this way is, that you can now bring up the back<span class="pagenum"><a name="Page_287" id="Page_287">[287]</a></span> -centre of your lathe to steady the cylinder cover while you -finish turning it; and as you will have to make a chuck -only to take hold of the flange <i>b</i>, while you turn the edge, -you will need probably some extra support of this kind. I -have, nevertheless, turned an iron cylinder cover 2½ inches -diameter without any such support; the actual strain not -being very severe, provided you understand how a tool -should be made and held.</p> - -<p>The above directions apply equally to the cylinder bottom, -the great secret in this and all similar work being to take -care to bed the work well and truly against the bottom of -the recess, turned in the chuck; this being neglected, will -result in the two faces not being parallel, which will terribly -throw out of truth the rest of your work. Indeed, in all -fitting of this kind, it is absolutely necessary to be exact -in the squaring and truing of each several piece that has -to be turned or filed; otherwise no planning or clumsy -arrangement will make your mechanism work as it ought -to do. Take a week, if necessary, over any part, and don’t -be content until it is <i>well</i> done.</p> - -<p>Your cylinder ought now to have a finished appearance -when the cover and bottom are placed in position, but the -latter have to be permanently attached by small screws, -and these I strongly advise you to buy. They cost about -50 cents a dozen, including a tap with which to make a -thread in the holes made to receive them; or, if you prefer<span class="pagenum"><a name="Page_288" id="Page_288">[288]</a></span> -it, you can buy miniature bolts and nuts at almost as -cheap a rate, which would cost you much time and trouble -to make for yourself, if, indeed, you succeeded at all. You -will want four of these for the top, and the same for the -bottom, the holes for which you will make with a small -archimedean or other drill.</p> - -<p>The mention I have made of this reminds me that I am -gradually adding considerably to your list of tools, and it -is necessary to do so if you take up model-making. Set -down, at any rate, the following:—</p> - -<ul> -<li><span class="smcap">Archimedean Drill-Stock</span> and <span class="smcap">6 Drills</span>.</li> -<li><span class="smcap">Table-Vice.</span></li> -<li><span class="smcap">Hand-Vice</span> or <span class="smcap">Pin-Vice</span>.</li> -<li><span class="smcap">Small Brass-Back Saws</span> for <span class="smcap">Metal</span>.</li> -<li><span class="smcap">Pair</span> of <span class="smcap">Small Pliers</span>.</li> -</ul> - -<p>And for use in the lathe, either two or three sizes of rose-bits, -or engineer’s half-round boring bits, of which I shall -have to speak presently; and, unless you buy <i>all</i> screws -and nuts, you will want screw-plate and taps, or small -stock and dies. Files of square, round, and oblong section -are matters of course. Remember, too, that after a file -has been used on iron and steel, it is useless for brass; so -use new ones on the latter metal first, and after such use -they will answer for cast iron and then for wrought iron. -You will find the cost of files rather heavy unless you -attend to this. Have neat handles to all your smaller files, -with ferules to prevent splitting.</p> - -<p><span class="pagenum"><a name="Page_289" id="Page_289">[289]</a></span></p> - -<p>When you purchase the castings of the engine, you will -find a valve-box to enclose the slide and become a steam-chest, -as explained. It is like a box with neither top nor -bottom, but with a flange, or turned-out edge all round, for -the screws by which it is to be attached to the valve-facings -of the cylinder. This box must have its flanges filed up -bright on their flat sides and edges—the rest may be painted. -It will exercise your skill to get the two faces flat and true, -to fit upon the cylinder; and at last you will find it expedient -to put a brown paper rim or washer between the -surfaces, or a bit of very thin sheet lead, to make a steam-tight -joint. Do not solder it, if it is possible to use screws, -because this is nearly certain to get melted off; and, if not, -it is not nearly so neat and workmanlike a way of uniting -the parts. You should, indeed, in all models, put them -together in such a way as to be able at any time to -separate the different pieces again, either for the purpose -of cleaning or repair; and, if you solder, you cannot easily -do this.</p> - -<p>The valve-casing and its back are generally put on -together; four screws at the corners passing through the -back and <i>both</i> flanges into the flat side of the cylinder. -This depends, however, upon the exact shape of these -different pieces; and I can give you no special directions -for a particular case unless I could see the castings which -you have to fit together. The stuffing-box you will make<span class="pagenum"><a name="Page_290" id="Page_290">[290]</a></span> -quite separate, both its outer and inner part, and screw or -solder the former into place. It is seldom cast upon the -valve-casing, because of the difficulty of chucking a cubical -object safely so as to turn any part of it.</p> - -<p>You are not to screw or solder the valve-box to the -cylinder until you have carefully filed up the valve itself to -slide upon the port face, without the possibility of any escape -of steam taking place. This needs the greatest possible -care; and probably, after doing what you can with a flat -file, you will have to put a little emery and oil between -the surfaces, and grind them to a perfect fit, by rubbing -them together. This grinding with emery is an operation -frequently required in mechanical engineering. Lathe-mandrels -are fitted in this way into the collars; the -cylinder is also ground into the back poppit-head. It is -not a very long or difficult operation, but whenever you -have had to use it, take care to wipe off the emery, or it -will keep on grinding. It is indeed very difficult to do -this perfectly; and for very fine work, such as fitting the -mandrel of a screw-cutting lathe (<i>i.e.</i>, a <i>traversing</i> mandrel), -oilstone powder and crocus are used, in place of emery. -These, however, cut very slowly, making the operation of -grinding exceedingly tedious; and in the present instance, -emery will answer quite well enough. In <i>very</i> small -engines, a stroke or two of a file is all that is needed to fit -the valve, which is so small as hardly to be worthy of the<span class="pagenum"><a name="Page_291" id="Page_291">[291]</a></span> -name; but in an engine with cylinder of 1 or 2-inch bore, -it will be impossible to do with file alone, as well as you -can with grinding.</p> - -<p>The piston and piston-rod should be turned at the same -time, as already suggested in treating of the atmospheric -engine of Newcomen. By this, you will avoid getting the -piston “out of square” with its rod, as if you had bored -the hole for the latter askew—a not unusual occurrence.</p> - -<p>I do not mean to say that it is absolutely necessary for -you to turn the piston-<i>rod</i> at all, for, in models, it is generally -of round iron or steel-wire, which is as cylindrical as -you can possibly make it. Knitting-needles are in general -use for this, as being well finished and equalised from end -to end. But these are rather hard, being tempered only to -about the degree of steel-springs; therefore you must never -attempt to cut a screw on them until you have first heated -the end to be screwed red-hot, and allowed it to cool again -very slowly. If you do this, a screw-plate will put a sufficiently -good thread to allow you to attach either the piston, -or the small piece of brass necessary to form the hinge, -upon the other end of the rod—that is to say, the piece -marked H in Fig. 64. Leave this for the present, however, -not attempting at present to cut either the piston-rod -or valve-rod to its intended length. You cannot do this -until you have laid down the exact plan of the engine, and -marked on the bed-plate the position of all the parts.</p> - -<p><span class="pagenum"><a name="Page_292" id="Page_292">[292]</a></span></p> - -<p>I shall now suppose that you have finished the cylinder, -with its slide-valve, casing, stuffing-boxes, and piston, so -that you have these in exactly the state in which you might -buy them at Bateman’s and elsewhere, if you preferred, to -spare yourself the trouble of boring the cylinder and fitting -it. You can buy them just in this condition, with the rest -of the castings in the rough; but I rather hope you may -prefer to try and do for yourself the not <i>very</i> heavy or difficult -work which I have described.</p> - -<p>I suppose you, indeed, to have bought the forked connecting-rod, -either arranged for brasses, or with holes -drilled (or to be drilled) in the ends, which would probably -be the case for a model of the size named, and also the -various bearings, guides, and so forth required—some of -which would have to be turned, and some filed, but which -ought now to present little difficulty to our young -mechanic.</p> - -<p>Try to keep sharp edges to all your filed work, unless <i>evidently</i> -intending to round them; for surfaces pretending to -be flat, but partaking of a curved sectional form, characterise -the workman as undeniably a bad hand with the file, -and not worth his wages. Still I may tell you at once that -nothing is so difficult as to use a file well. It has a knack -of rounding off edges, which always get more than their -proper share of its work. But this being the case, you will -know what to try and avoid. Therefore, always endeavour<span class="pagenum"><a name="Page_293" id="Page_293">[293]</a></span> -in filing a flat surface to make it slightly hollow in the -middle, which it is scarcely possible, however, for you to -do; but the endeavour to effect this by filing the middle -more than the edges will help you wonderfully in keeping -the latter sharp. Those, for instance, on the fork of the -connecting-rod, especially the inside ones, should be as -straight and sharp as possible; and if you round the outside -edge, take care to do it so that it shall be evident you -intended it; and so with all edges, whether turned or -filed.</p> - -<p>The disc of the eccentric can only be turned by letting it -into a chuck to something less than half its thickness, and -levelling one side and half the edge, and then reversing it; -unless you prefer to drill and mount it on a spindle upon -its centre. If you do this, you will of course eventually -have two holes in it; because this first one is not that by -which it will be mounted when in place. This second hole -is not, however, of the least importance, and may be left -without plugging, and, if preferred, may become in part -ornamented by drilling additional holes, and filing them -into some pattern; or if it is desired to conceal the one it -was turned upon, this can be plugged and faced off, and -will then not be the least apparent. If the outer ring, or -strap, as it is called, is to be made in two pieces, with projecting -lugs, it is evident the outside edge cannot well be -turned; and, unless you have that most useful addition to<span class="pagenum"><a name="Page_294" id="Page_294">[294]</a></span> -the lathe, a grip or jaw-chuck, you will have some little -difficulty in letting the ring into a wooden chuck, so as to -turn the inside. The solid ring is, therefore, preferable (if -you use the first, however, you turn it up as a single ring, -and then saw it across through the lugs), which can be let -into a common chuck, with a place chiselled out to allow -the boss to project, into which the eccentric rod has to be -screwed. This boss also has to be drilled and turned on -the outside. There are several modes of chucking it which -can be applied, but the simplest is to use the carrier-chuck, -and to let the ring become its own carrier by coming against -the pin, as shown in Fig. 66, A.</p> - -<p>When the ring is <i>very</i> small, I should first drill the hole -for the wire rod, and then screw and mount it upon a little -wire spindle, as in fig. B, aiding this, if necessary, by the -back centre. But the smallest models require to be put -into a watchmaker’s lathe or throw, and, except as curiosities, -are scarcely worth making.</p> - -<p>I have already told you never to undertake engine-making -without first laying down a full-sized plan on paper, -with centre lines through the principal parts, from which -to take all measurements, and to mark these upon the base-plate, -as a guide to the perfect adjustment of the various -parts. Some of these are capable of a little extra adjustment -after being put in place: the eccentric rod, for -instance, can be lengthened or shortened by screwing into<span class="pagenum"><a name="Page_295" id="Page_295">[295]</a></span> -or out of the eccentric ring; and the piston-rod, too, may -be similarly lengthened or shortened slightly; but try to -work as near as you can to precise measure without such -adjustment.</p> - -<p>To turn the fly-wheel, which is the last operation (including -the crank-axle), it is better carefully to drill the -boss, if not already done, marking the centre on each side, -and working half through from each, so as to insure the -squareness of the hole with the side of the wheel, which is -very important. Then mount it at once upon its axle, previously -turned slightly conical, where the wheel is to be -placed, and run both together in the lathe. This will -insure the wheel running true when the engine is put -together.</p> - -<p>In the horizontal engine which I have sketched, the -crank is quite separate from the axle; and this is the easiest -way to make it. The crank itself is filed up, like C of fig. -66, and drilled for the axle and the pin upon which the -brasses on the connecting-rod work. Turn down the end -of the crank-shaft <i>very</i> slightly conical, until the crank -will <i>almost</i> go over it. Then heat the crank, which will -expand it and enable you to slip it on the shaft. Dip it in -cold water, and it will be as firm as if made in one piece -with the axle. This is called shrinking it on, and the -operation will often stand you in good stead, and save the -trouble of filing key-ways and making the small wedges<span class="pagenum"><a name="Page_296" id="Page_296">[296]</a></span> -called keys. The pin D can in this case be turned -up separately, and screwed in, which will complete the -work.</p> - -<p>The eccentric must evidently be placed in position before -the crank is added, and this, too, might be shrunk on, were -it not that it cannot easily be fixed in a model until the -engine is set up. The best way, therefore, is, in this case, -to turn the eccentric with a little projecting boss to take -a set screw, E, Fig. 66.</p> - -<p>Where the axle has to pass through bearings, it must be -turned down at these parts, so that the whole will be like F. -First on the right is the journal, <i>e</i>, then the place for the -fly-wheel, <i>d</i>, very slightly conical—the smallest part being -towards <i>e</i>—then the second journal, and then another -slightly conical part, the smallest end towards <i>a</i>, to take -the eccentric and crank. The fly-wheel you will key on shaft, -thus:—G represents the boss or centre of the wheel bored -for the axle, and a key-way or slot filed on one side at <i>a</i>. -There is a flat place filed on the axle, and the wheel is -turned round to bring this opposite to the key-way. A -wedge or key, <i>b</i>, is then driven in, which keeps the wheel -secure, and prevents it from turning round or working -loose on the axle. If inconvenient to turn a boss and add -a set-screw to the eccentric, this also may be keyed in its -place after its position has been found; but, for the latter -purpose, it should fit rather tightly on the axle, so that it -can be just moved round with the finger stiffly until its -position with respect to the crank is ascertained.</p> - -<p><span class="pagenum"><a name="Page_297" id="Page_297">[297]</a></span></p> - -<div class="figcenter" style="width: 400px;" id="fig66"> -<img src="images/figure66.jpg" width="400" height="600" alt="" /> -<p class="caption">Fig. 66.</p> -</div> - -<p><span class="pagenum"><a name="Page_298" id="Page_298">[298]</a></span></p> - -<p>This position I shall now endeavour to explain, using a -diagram from an American work, in which this generally -supposed difficult point is thus ably and satisfactorily explained. -First, put your engine together as if for work, -and having cut the eccentric rod to about the length you -seem to require, judging from your plan drawn upon the -bed-plate, turn round the eccentric, with your fingers upon -the crank-shaft, and, having removed the cover of the -valve-box, so that you can see the action on the valve, -watch the motion of the latter. Doubtless, the result will -be that one of the steam-ports will be opened clear to the -exhaust-port, while the other is nearly or entirely shut. -The rod is then too long or too short. If in a horizontal -engine the port nearest to the crank is wide open and the -other shut, the rod is too long, and must be shortened <i>half</i> -the difference only (<i>you</i> will do this by screwing it farther -into the eccentric hoop). When the valve “runs square,” -or opens and shuts the ports correctly, set the eccentric as -in the diagram, H, in respect to the crank, <i>i.e.</i>, with its -widest part at right angles to it. By running square is -meant that when the eccentric is turned round as described, -the valve opens the ports equally, and does not affect one -more than the other. The line <i>a</i> of the diagram shows -that the position of the eccentric may advantageously be a<span class="pagenum"><a name="Page_299" id="Page_299">[299]</a></span> -little <i>beyond</i> the right angle to the crank, to give what is -called “lead,” <i>i.e.</i>, to open the valve a little before the -piston commences its return-stroke.</p> - -<p>The boilers of model engines are made of tin, sheet-brass, -or copper; seldom of the latter, which is, nevertheless, by -far the best material, and one that you can braze, rivet, or -solder satisfactorily, or bend into any shape with a hammer -or wooden mallet. When polished, too, its rich red colour -is very handsome. Brass is chiefly used from the facility -of obtaining tubes of it ready brazed or soldered, from -which any desired length can be cut. A brazed copper -boiler will stand a great deal of pressure; will tear, and -not fly into pieces when it bursts; and may be heated after -the water has boiled away without suffering any injury. It -would certainly not be worth while to make one for a model -engine with a half-inch cylinder, but for one of 1 inch diameter -and 2½ stroke; and for larger sizes, it will amply repay -the trouble; and I will show you how to make one, with a -tube or flue inside to add to the heating surface.</p> - -<p>I shall endeavour presently to give the proper dimensions -of boilers to work cylinders of given diameters, but the -general directions here subjoined apply to all boilers of -models, whether large or small. The main body of the -boiler is generally cylindrical, and is, in fact, a tube of -sheet-metal, with riveted, brazed, or soldered seams, the -last greatly predominating in the toy engines; the result of<span class="pagenum"><a name="Page_300" id="Page_300">[300]</a></span> -which is, that the first time the water gets too low, out -drops the bottom, or, at the least, divers leaky places appear, -and the boiler is obliged to go to the tinman’s for repair, -its beauty being ever after a thing of the past. It is difficult -to braze in an ordinary fire; because even if, by blowing -it with a pair of bellows, you get sufficient heat, you cannot -always manage to apply your work in a good position, as -you can over the hot coals of a forge fire, where there are -no bars, hobs, or other parts of the grate standing in the -way. Moreover, you often want both hands free just as the -solder commences to “run,” and forge-bellows will keep up -the blast for a few seconds after your hand is taken from -the staff or handle of them. Still, if you have no forge, -which is probable, you should make a fire of cinders or coke -(the latter if possible); and if you can contrive a grate by -putting together a few bricks in some out-house, with a -bar or two of hoop-iron below for the coke to rest upon, you -will have a far more convenient fire to work at than can -possibly be obtained in any ordinary household grate or -stove. You will require a pair of light tongs, which <i>ought</i> -to be something like A, Fig. 67; but it is quite possible to -do without these if you can hold your work in any other -way; as, for instance, with a loop of iron wire twisted -round it and left long enough to form a handle.</p> - -<p>The first thing to do is to cut a strip of copper large -enough to make the required tube. A piece 6 inches wide<span class="pagenum"><a name="Page_301" id="Page_301">[301]</a></span> -will roll up into a cylinder of about 2 inches diameter (the -circumference of a circle being nearly equal in all cases to -three times its diameter, or measure through the centre). -If, therefore, you want one 6 inches across, which is the -smallest size that can be advantageously fitted with a flue -or internal tube, you must cut it out 18 inches wide, and if -it is 8 in length to the bottom of the steam dome, it will -be a large and serviceable boiler, fit to work an engine with -a cylinder of 1½ bore by 2½ or 3 inch stroke, which would -drive a small lathe. But observe that if you really have -pluck and skill enough to try your hand upon an engine -that will give you real <i>power</i>, you must take care to remember -that “the strength of anything is the strength of its -<i>weakest</i> part.” So don’t make the very common mistake -of having a good boiler and ample cylinder, and then fit -the engine with piston-rod, valve-rod, and such like, too -small to bear the strain which you propose to put upon the -engine. Remember that every screw and nut and pin upon -which strain is liable to fall, must be of sufficient size and -strength to bear it safely: if not, your engine will not only -come to grief in the heavy trial, but it is quite possible that -you also may become subjected to a bad scald or other -disagreeable consequence of your error.</p> - -<p>Whatever sized strips of copper you use for a boiler, the -edges have to come together to form what is called a butt-joint; -<i>i.e.</i>, they do not overlap like the ordinary joints you<span class="pagenum"><a name="Page_302" id="Page_302">[302]</a></span> -see made in tin. Before you coil up the strip into a tubular -shape, you have to cut out holes for any boiler fittings you may -wish to add, such as safety-valve, steam-dome, and gauges -to ascertain the level of the water. These, however, do -not all come into the cylindrical part of our present boiler; -the gauge-taps and glass water-gauge alone having to be -provided for. The man-hole, too, which is added to all -large boilers, may be dispensed with, its object being to -enable one to get at the inside, which will scarcely be -necessary if our work is well done at first. A boiler of the -proposed size should be heated with charcoal, as it would -require a very large lamp; but where gas can be obtained, -it may be preferably used, a ring gas-burner being placed -below within the furnace. The object of a steam-dome, -which, in a horizontal boiler, would have to be placed -somewhere on the tube itself, is to prevent what is called -priming, <i>i.e.</i>, the carrying into the cylinder water as well -as steam, which arises from the spurting caused by the -violent boiling of the water. The dome merely provides -a chamber for dry steam above the general level of the -boiler, the steam-pipe passing from it direct to the cylinders. -Our present boiler will be vertical like the last, but -with a flue up the middle, and a grate fitted below. It -is shown complete in Fig. 67, B, with all the fittings -usually attached.</p> - -<p>Having coiled up the tube by hammering it over a<span class="pagenum"><a name="Page_303" id="Page_303">[303]</a></span> -cylinder of wood turned for the purpose, a little smaller -than the intended size of the boiler (the edges having been -previously filed up bright, and a width of a quarter of an -inch of the upper being similarly cleaned on the inside all -along the seam), a few loops of iron wire are tied round -it, at intervals of 1 inch or 1½ inches; there being a short -piece put round, and twisted together at the ends by a -pair of pliers. The object of these is to prevent the seam -from opening on the application of heat, which it is otherwise -certain to do by the expansion of the metal. Some -borax, pounded in a mortar, and heated to drive off the -water of crystallisation, is next mixed with a little water -to form a creamy paste, and smeared along the inside of -the tube, upon the brightened part, the full length of the -seam. It is generally better to heat this salt first sufficiently -to dry it (or rather fuse it), because it swells -prodigiously by the first application of heat, and if the -spelter is laid on it, it often carries it off; after once -fusing, it only melts quietly.</p> - -<p>Before applying the little lumps of spelter, turn over -the tube to heat the part opposite to the seam, so as to -equalise the expansion. Then hold it in a pair of light -tongs, lay the spelter all along upon the borax, and expose it -without actually touching the coals to the heat of the fire, -urged by a strong blast. Continue this until a blue flame -arises, which shows that the spelter has melted; this blue<span class="pagenum"><a name="Page_304" id="Page_304">[304]</a></span> -flame being, in fact, that caused by the burning of the -zinc in the solder—spelter being copper and zinc fused -together, or, if required softer, brass, tin, and zinc. The -former is generally used, however, on copper. When the -blue flame arises, the solder runs into the joint, and the -work is done. With the hardest of these spelters, a red -heat will not seriously affect the joint, and, therefore, if at -any time the water should get below the line of this seam, -so that it becomes exposed to the heat, no harm will be -done. Nevertheless, this ought never to occur, as a gauge -should be attached to every boiler to show the exact -position of the water at any given time.</p> - -<p>The inside tube of this boiler will be seen, from the -section, to be conical up to the level of the lower part of -the chimney. This is of copper, brazed like the cylindrical -part, and is 2 inches wide below, and 1 inch above; consequently, -the strips to make it must be 6 inches wide at -one end, and taper to 3 inches at the other. If the dome -rises 2 inches from the level of the top of the cylinder, it -will be sufficient; and as this is a difficult piece of work -for a boy to manage, a coppersmith should be asked to -hammer the dome into the required form, as he will know -from experience the best size of circular disc to use for the -purpose. This part is so far removed from the action of -the fire that it may safely be soldered, but it is, nevertheless, -as well to rivet it, turning <i>out</i> both the edge of the<span class="pagenum"><a name="Page_305" id="Page_305">[305]</a></span> -cylinder and that of the dome. Use copper rivets, and -make the holes half an inch apart. If you find any -leakage, you can run a little solder into the joint on the -inside. The bottom of the boiler may be quite flat and -brazed, a few rivets being first put in to hold the parts -accurately together. The same may be said of the tube -which passes through both this and the dome. There is -nothing equal to riveting and brazing for this kind of -work.</p> - -<p>I may as well state however here, that as such a boiler -as I have now described is worth very good work, it would -be a great pity to spoil it; and it will be better to content -yourself with smaller boilers and engines soldered, where -necessary, until you have had some practice in brazing. -This indeed is not difficult in reality, but, at the same time, -requires great care, because sometimes the solder and the -work melt at so nearly the same temperature, that, like a -bad tinker, you will sometimes make two holes instead of -mending one. The brass, for instance, used for beer-taps -is very soft, and contains lead, and to a certainty would -itself melt before ordinary spelter, and could not therefore -be brazed; but the best Bristol brass, or yellow metal, -will braze easily. A blacksmith, brazing a key or other -iron article, will braze it in a different way, using brass -wire, with which he will envelop the parts thickly which -are to be united, after securing their position with <i>iron</i> -binding-wire. He then sprinkles with borax, and heats -the work until the wire runs into the joint; after which he -files and cleans off level. This makes a very good medium.</p> - -<p><span class="pagenum"><a name="Page_306" id="Page_306">[306]</a></span></p> - -<div class="figcenter" style="width: 400px;" id="fig67"> -<img src="images/figure67.jpg" width="400" height="600" alt="" /> -<p class="caption">Fig. 67.</p> -</div> - -<p><span class="pagenum"><a name="Page_307" id="Page_307">[307]</a></span></p> - -<p>I have spoken of <i>riveting</i> in this place. There is no -difficulty in this work. You can buy copper rivets of all -sizes, and have only to punch holes, put a rivet in place, -and hammer it so as to spread the metal to form a second -head. If the rivets are heated before being applied, they -will draw the parts closer together, because they shrink -in cooling. All large boilers are made in this way, but -smaller ones of iron are often <i>welded</i>, where such a mode of -junction is possible. When you can rivet boilers water -and steam tight, you will find no difficulty in constructing -them, for you can make riveted joints where brazing -would be difficult or impossible.</p> - -<p><span class="pagenum"><a name="Page_308" id="Page_308">[308]</a></span></p> - -<div class="figcenter" style="width: 400px;" id="fig68"> -<img src="images/figure68.jpg" width="400" height="600" alt="" /> -<p class="caption">Fig. 68.</p> -</div> - -<p>Fig. 67, B, is a half-section of such a boiler as I have -just described. Fig. 68, A, is the lower part, which is -separate, and forms the furnace in which the boiler stands, -fitting it closely. This is drawn to scale, and is half the -real size. <i>a</i> is the steam-pipe, fitted high up in the dome, -the tap, <i>b</i>, serving to turn on or off the supply of steam for -the cylinder; <i>c</i> is the safety-valve shown in section, and -care must be always taken to make the conical part short -and of a large angle, or it may stick fast, and cause an -explosion; <i>d</i> is the glass gauge, to show the exact height -of the water in the boiler. Its construction will be understood<span class="pagenum"><a name="Page_309" id="Page_309">[309]</a></span> -from the other which is attached, where the boiler is -seen in section. There is no need to have two, and this is -added solely to explain the nature of glass-gauges. The -top and bottom are of brass, being tubes screwing into the -boiler, or fastened by a nut inside; a tube, <i>g</i>, of thick -glass, connects these two, so as to form a continuous tube, -one end of which opens into that part of the boiler which -is full of steam, the other opening below the water-level. -Thus the tube forms practically part of the boiler, and the -level of the water is clearly seen. The lower tap is used -for blowing off water, to insure the communication being -kept open, as it might get stopped up with sediment.</p> - -<p>Gauge-cocks, <i>e</i>, <i>f</i>, are generally added, even where the -glass water-gauge is used. One of these should always -give steam, the other water,—the level of the latter being -between the two. If the upper one gives water, the boiler -is too full; if both give steam, the boiler needs to have -water added. With these fittings, even a soldered boiler -ought never to get burnt, and will last a long time with -care.</p> - -<p>The lower part, Fig. 67, is made like that before described, -except that, being intended for charcoal, a circular grate -is used, which simply rests upon little brackets fixed by -rivets for this purpose. The flame and heat play upon the -bottom of the boiler, and also pass up the central tube—the -latter adding greatly to the quantity of steam produced.<span class="pagenum"><a name="Page_310" id="Page_310">[310]</a></span> -This furnace, when lighted, may be fed with bits of coke as -well as charcoal, about the size of filberts, and will give -plenty of heat. If the draught, however, is deficient, turn -the waste steam into the tube, so as to form a jet at each -stroke, and it will greatly increase it. It is in this way -that the locomotive engines are always fitted, George -Stephenson having first suggested the arrangement. Previously -to this a fan had been fitted below the grate, which -was put in rapid motion by the engine, and thus a sufficient -draught was obtained.</p> - -<h3>THE SAFETY-VALVE.</h3> - -<p>To find out what pressure is exerted by the safety-valve, -it must be clearly understood upon what principle it acts. -I have in a previous chapter told you that the atmospheric -pressure equals 15 lbs. on each square inch, so that if the -surface of the valve which is exposed to the air is 1 inch -in area or surface, it is pressed down with a force of 15 lbs. -The steam, therefore, inside the boiler will not raise it until -its elasticity exceeds this atmospheric pressure. If, therefore, -we desire to have only just 15 lbs. per square inch -pressing against the inside of the boiler (<i>i.e.</i>, a pressure of -“one atmosphere,” as it is called), we have only to load -the valve so that, inclusive of its own weight, it shall -equal 15 lbs. But it is plain that we must not load it at -all in reality; for a flat plate, 1 inch square, of <i>no weight</i>,<span class="pagenum"><a name="Page_311" id="Page_311">[311]</a></span> -is all that is needed, the atmosphere itself being the load. -Suppose, then, that we <i>do</i> load it with 15 lbs. in addition to -the 15 lbs. with which nature has loaded it, we shall not -find the steam escape until it presses with a force of 30 lbs. -on the square inch, or two atmospheres (which, however, -is not 30 lbs. of <i>useful</i> pressure upon one side of the piston, -if the cylinder is open as in an atmospheric engine, but -only 15 lbs.) This is not the <i>strain</i> which the boiler has -to stand, because the atmosphere is pressing upon it and -counteracting it up to the 15 lbs., so that this strain tending -to burst it is but 15 lbs. The number of pounds, therefore, -which is straining the boiler can readily be seen; being -always that with which the safety-valve is loaded, and this -is also the useful pressure for doing any required work. Unfortunately, -however, even in the best constructed engines, -a pressure of 15 lbs. upon the boiler by no means represents -that in the cylinder. Now it would be inconvenient to -place weights upon the safety-valve itself, and therefore a -lever is added, as seen in the sketch, with a weight hung -at one end of it. This is shown at B, Fig. 68, where a -section of the valve is given with its stem passing through -a guide to insure the correct motion of the valve. The -lever is hinged at one end; and the rule of the pressure or -weight which is brought to bear upon the valve is, that it -is multiplied by the distance at which the weight hangs -from the valve, compared with its distance from the hinge<span class="pagenum"><a name="Page_312" id="Page_312">[312]</a></span> -or fulcrum. If a weight of 7 lbs. is hung at 1, <i>i.e.</i>, at a -distance as far on that side of the valve as the fulcrum is -on the other side of it, 7 lbs. will be the actual power -exerted; at 2, where it is twice the distance, it will be -doubled, and, as shown in the drawing, a pressure of 14 lbs. -will be brought to bear upon the valve; while, if the weight -is hung at 3, it will exercise a force of 21 lbs. This is very -easy to understand and to remember. Sometimes (always -in locomotives) the weight is removed and a spring balance -is attached at the long end. Upon this is marked the -actual pressure exerted; there being a nut to screw down, -and thus bring any desired strain upon the spring. Mind, -however, in case you should try this in any of your models, -that the scale marked on the balance when you buy it must -be multiplied, as before, according to the length of your -lever. Thus, if I attach such a balance at 3 of the drawing, -a real weight of 5 lbs. shown by the balance will be -3 × 5, or 15 lbs. upon the valve, and a balance <i>made for -such engine</i> would be marked 15 lbs., to prevent the possibility -of dangerous error.</p> - -<h3>ENGINES WITHOUT SLIDE-VALVES EASY TO MAKE.</h3> - -<p>Having been led on from the atmospheric engine to that -of Watt’s, and to slide-valve engines generally, I am now -going backward a little to a class easier to make, because -they have no slide-valves, nor even four-way cocks; and<span class="pagenum"><a name="Page_313" id="Page_313">[313]</a></span> -then I shall have done with engines. But I dare say some -of my readers will wonder why I have said so little about -condensers and condensing engines. I am sure they will -wonder at it if they understood what I explained of the -advantage of a vacuum under the piston; so that 15 lbs. -pressure upon the piston means 15 lbs. of <i>useful</i> work, instead -of 30 lbs. being required for that purpose. But condensing -engines are utterly beyond a boy’s power. They -require not only a vessel into which the steam is injected -at each stroke, but there must be a pump to raise and -inject cold water to condense the steam, and a pump to -extract from the vessel again this water, after it has been -used, and a cistern, and cold and hot wells; and all this is -difficult to make <i>so as to act</i>; and I am sure no boy cares for -a steam engine that will not work. Moreover, I have given -you difficult work as it is—work that many of my readers -will no doubt be afraid to try—yet I did it on purpose; -because if small boys are unequal to some of it, their big -brothers are not, or ought not to be; and mechanical boys -must look at difficulties as a trained hunter looks at a -hedge—viz., with a strong desire to go over it, or through -it, or any how and some how to get to the other side of it. -Indeed, you must ride your mechanical hobby very boldly -and with great pluck, or you won’t half enjoy the ride. -However, I am quite aware that I have led you into several -difficulties, and therefore now I propose to set before you<span class="pagenum"><a name="Page_314" id="Page_314">[314]</a></span> -some easy work as a kind of holiday task which will send -you with fresh vigour to what is <i>not</i> so easy.</p> - -<p>The engines without slide-valves have also no eccentrics -and no connecting-rods. There is just a boiler, a cylinder, -piston, piston-rod, and crank, and you have the sum total, -save and except the fly-wheel. These are direct-action -engines, the cylinders of which oscillate like a pendulum, -and the piston-rod itself is connected to the crank, doing -away with the necessity for guides.</p> - -<p>Fig. 69, A, shows one of these engines, and you see that -the cylinder leans to the left when the crank is turned to -that side; and if you turn the wheel to the right, the crank -will presently cause it to lean the other way; and thus, as it -turns on a pin, or “trunnion,” as it is called, it keeps -on swinging from side to side as the wheel goes round.</p> - -<p>Now, when it is in its first position, the piston is at the -bottom of the cylinder, and it then needs to have the steam -admitted below it to drive up the piston; but when this -has passed its highest position, and the cylinder is turned -a little to the <i>right</i>, the piston must be allowed to descend, -and, therefore, we must let out the steam below it. We -<i>ought</i>, at the same time, to admit steam above the piston -to force it down; but, in the simplest models, which are -called single-action engines, this is not done. The fly-wheel, -having been set in motion, keeps on revolving, and, -by its impetus, sends down the piston quite powerfully<span class="pagenum"><a name="Page_315" id="Page_315">[315]</a></span> -enough to overcome the slight resistance which is offered -by the friction of the parts.</p> - -<p>Now, you can, I daresay, -easily understand that it is possible -to make this to-and-fro -motion of the oscillating cylinder -open first a steam-port to -allow steam to raise the piston, -and then an exhaust-port to let -it blow off into the air. This -is exactly what is done in practice, -and it is managed in the -following manner:—</p> - -<div class="figcenter" style="width: 200px;" id="fig69"> -<img src="images/figure69.jpg" width="200" height="500" alt="" /> -<p class="caption">Fig. 69.</p> -</div> - -<p>B, of Fig. 69, shows the -bottom of the cylinder, which -is a solid piece of brass filed -quite flat on one side, and -turned out to receive the end -of the brass tube, which, generally -speaking, is screwed into -it to form the cylinder, this -being the easiest way to make -it. In the middle of the upper -part of the flat side you see a -white steam-port, and below it -a round white spot, which is the position of the pin, or<span class="pagenum"><a name="Page_316" id="Page_316">[316]</a></span> -trunnion, on which it oscillates. Fig. 69, C, is a similar -piece of brass, which is fixed to the top of the boiler. In -this, on the <i>left</i> of the upper part, is also a port, which is -connected with the boiler by a hole drilled below it to -admit steam. On the right is also a port, which is merely -cut like a notch, or it may go a little way into the boss, -and then be met by a hole drilled to meet it, so as to form -the escape or exhaust port. Between and below these is -the hole for the trunnion.</p> - -<p>Now, you can, I think, see that if the cylinder stands -upright against this block, as it does when the crank is -vertical (or upright) and on its dead points, the port at the -bottom of the cylinder would fall between the two on this -block of brass, and, as they are both flat and fit closely, no -steam from the boiler can enter the cylinder. Nor do we -want it to do so, because, if the crank is on a dead point, -no amount of steam can make the piston rise so as to move -it. But now, if we move the cylinder to the left, which we -can do by turning the wheel, we shall presently get the -crank at right angles to its former position, and, also, we -shall bring the steam-ports in the cylinder and block -together, so that steam will enter below the piston. But, -practically to get as long a stroke as possible, steam is not -allowed to enter fully until the crank is further on than in -a horizontal position, that is, <i>approaching</i> its lower dead -point; and this is the position in which to put it to start<span class="pagenum"><a name="Page_317" id="Page_317">[317]</a></span> -the engine. By altering the shape or the position of the -port a little, we can so arrange matters as to let steam -enter at any required moment.</p> - -<p>Steam having entered, the piston will rise rapidly, forcing -up the piston, and presently, by the consequent revolution -of the fly-wheel, the cylinder will be found leaning to the -left, and at this moment the piston must evidently begin -to descend. At this very time the steam-ports will have -ceased to correspond, but the port in the <i>cylinder</i> will come -opposite the exhaust-port in the brass block, and this port -is made of such size and shape that the two shall continue -to be together all the time the piston is descending; but, -the moment it has reached the end of its downward stroke, -they cease to correspond in position, and the steam-port -begins again to admit a fresh supply of steam.</p> - -<p>The pillar attached to the brass boss has nothing to do -with it, but is one of the supports of the axle of the fly-wheel, -as you will understand by inspection of A of this -same drawing.</p> - -<p>Such is the single-action model engine, <i>of no power</i>, but -a very interesting toy and real <i>steam</i> engine.</p> - -<p>The double-action engine is very superior to the foregoing, -which, I may remark, has no stuffing-box, and of which the -piston is never packed. I may also add, that the crank is -formed generally by merely bending the wire that forms the -axle of the wheel, and putting the bent end through the hole<span class="pagenum"><a name="Page_318" id="Page_318">[318]</a></span> -of a little boss or knob of brass, screwed to the end of -the piston-rod. Here you have no boring of cylinders -to accomplish, but the cylinder cover, piston, and wheel -(often of lead or tin) require the lathe to make them neatly. -Many an engine, however, has been made without a lathe, -and I have seen one with a bit of gun-barrel for a cylinder, -and a four-way cock of very rough construction, that was -used to turn a coffee-mill, and did its work very well too.</p> - -<p>But I must go at once to the double-action oscillating -cylinder, in which, although a similar mode of admitting -steam is used, it is arranged to admit it alternately above -and below the piston, the exhaust also acting in a similar -manner.</p> - -<p>After the explanation I have given you, however, of the -single-action engine, you will, some of you, I think, jump -at a conclusion almost directly, and perhaps be able to plan -for yourselves a very easy arrangement to accomplish the -desired end. All boys, however, are not “wax to receive, -and adamant to retain” an impression; for I have known -some who need an idea to be driven into their brains with a -good deal of hard hammering. Stupid?—No. Dull?—No, -only slow in <i>getting hold</i>, and none the worse for that generally, -if the master will but have a little patience; for when -they <i>do</i> get hold, they are very like bulldogs, they won’t -let go in a hurry, but store up in most retentive minds -what they learned with such deliberation.</p> - -<p><span class="pagenum"><a name="Page_319" id="Page_319">[319]</a></span></p> - -<h3>THE DOUBLE-ACTION OSCILLATING ENGINE.</h3> - -<p>The cylinder of the double-action engine is of necessity -made with ports very similar to those of the horizontal -engine already described. There is a solid piece attached -to the cylinder as before, which is drilled down to the upper -and lower part respectively of a central boss, turned very flat -upon the face, and which has to work against a similar flat -surface as in the last engine. But the ports in the latter -are four instead of two, and in an engine with upright -cylinder would be cut as follows, and as shown in Fig. -70, C.</p> - -<div class="figcenter" style="width: 500px;" id="fig70"> -<img src="images/figure70.jpg" width="500" height="500" alt="" /> -<p class="caption">Fig. 70.</p> -</div> - -<p>Those on the right marked <i>st</i> are steam-ports, which, being -drilled into one behind, are connected with the boiler. The -other two marked <i>ex</i>, are similarly exhaust-ports opening into -the air. The spaces between <i>a b</i> and <i>c d</i> of fig. C must be -wide enough to close the steam-ports in the cylinder, when -the latter is perpendicular and the engine at rest. When -the cylinder leans to the left, oscillating on the central pin -between the ports in the middle of the circle, the lower port -of it will evidently be in connection with the steam-port in -C, while the upper port of the cylinder will be opposite to -the exhaust. As the cylinder is carried over towards the -right, the upper steam-ports will come into action in a -similar way, while the lower exhaust-port is also carrying -off in turn the waste steam. The impetus, therefore, of the<span class="pagenum"><a name="Page_320" id="Page_320">[320]</a></span> -fly-wheel has here only to carry the ports over the spaces -<i>a b</i>, <i>c d</i>, and to prevent the crank stopping on the two dead -points. This, therefore, is a genuine double-action engine, -and will answer, even on a large scale, very satisfactorily. -If you do not quite understand the action of these ports, cut -out two pieces of card, E F. Let E represent the cylinder. -Draw circles, and cut two ports. Cut another piece of card<span class="pagenum"><a name="Page_321" id="Page_321">[321]</a></span> -to represent the brass block, with ports, <i>c d</i>; pin them -together through the centres of the circles, and they will -easily turn on the pin. Mark the ports, so that you will -see at a glance which are steam and which exhaust. Now -cut out the ports with a penknife, and as you work the two -cards together, swaying that which represents the cylinder -to and fro upon the other, you will see when the ports in -each card agree with one another, and which are opposite to -which. This will teach you far better than any further -written explanation. You will also see that, instead of -making the steam and exhaust ports respectively with a -division between, the two steam-ports may be in one curve -united, and likewise the two exhausts; but take care not to -unite the exhaust with the steam-ports. There is no way -so easy as this of reversing the action of the steam; it is, in -fact, a circular slide-valve, but wonderfully easy to make, -because you have no steam-case to make, nor any attachments -whatever.</p> - -<p>The faces of the valve are kept in close contact in one of -two ways—either the centre-pin is fixed into the cylinder -face, and after passing through the brass boss with the -ports, is screwed up with a nut at the back; or else there is -fixed a small pillar or upright on the opposite side of the -cylinder, and a little pointed screw passing through this -presses against the cylinder, and makes a point of resistance, -against which it centres, and on which it turns. This<span class="pagenum"><a name="Page_322" id="Page_322">[322]</a></span> -is shown at fig. A. A small indentation is made where the -point comes in contact with the cylinder.</p> - -<p>In a locomotive engine there are two such cylinders, -working against opposite faces of the same brass block -containing the ports. The cranks are also two, on the -shaft of the driving-wheels, and are at right angles to each -other; so that when one piston is at the middle of its -stroke, the other is nearly or quite at the end of it. Thus, -between the two there is always some force being exerted -by the steam; and the dead points of one crank agree with -the greatest leverage of the other. In locomotives, too, the -cylinders generally are made as in the present drawing, -viz., to oscillate on a point at the middle of their length; -but it is just as easy to have the two ports meet at the -bottom instead, so that the point of oscillation may be low -down, like the single-acting cylinders of the last sketch, -and this is generally done when the cylinder is to stand -upright.</p> - -<p>There is no occasion for me to draw an engine with -double-acting oscillating cylinders, because in appearance -it would be like the single-acting one; but whereas the -latter is of absolutely no use, seeing that the greater part -of its motion depends on the impetus of the fly-wheel, the -former can be made to do real work, and is the form to be -used for marine and locomotive engines. For the former, -oscillating cylinders with slide-valves are used in practice;<span class="pagenum"><a name="Page_323" id="Page_323">[323]</a></span> -but for real locomotives fixed cylinders are always used. -Of course either will answer in models, and it will be good -practice to try both.</p> - -<p>I have now given sufficient explanation of how engines -work, and how they may be made, to enable my young -mechanic to try his hand at such work. The double-action -oscillating engines especially are well worthy of his attention, -as he may with these fit up working models of steam-boats -and railway trains, which are far more difficult to -construct with fixed cylinders and slide-valves. I shall -therefore close this part of my work with a description of -one or two useful appliances to help him in the manipulative -portion of his labour,—for here, as in most other -matters, head and hand and heart must work together. -The heart desires, the head plans, the hands execute. I -think, indeed, I might without irreverence bring forward -a quotation, written a very long time ago by a very clever -and scientific man, in a very Holy Book: “Whatsoever thy -hand findeth to do, do it with all thy might.” Depend -upon it, success in life depends mainly upon carrying into -practice this excellent advice. If you take up one piece of -work, and carelessly and listlessly play at doing it, and -then lay it down to begin with equal indifference something -else, you will never become either a good mechanic or a -useful man. If you read of those who have been <i>great</i> men—lights -in their generation—you will find generally that<span class="pagenum"><a name="Page_324" id="Page_324">[324]</a></span> -they became such simply by their observance of that ancient -precept of the wise man. They were not so marvellously -clever—they seldom had any unusual worldly advantages; -but they worked “with all their might,” and success -crowned their efforts, as it will crown yours if you do the -same.</p> - -<div class="figcenter" style="width: 250px;"> -<img src="images/footer2.jpg" width="250" height="125" alt="" /> -</div> - -<hr /> - -<p><span class="pagenum"><a name="Page_325" id="Page_325">[325]</a></span></p> - -<div class="figcenter" style="width: 500px;"> -<img src="images/header5.jpg" width="500" height="110" alt="" /> -</div> - -<h2 id="CHAPTER_XV"><span class="smcap">Chapter XV.</span></h2> - -<h3>HARDENING AND TEMPERING TOOLS.</h3> - -<p>I promised in a previous page to describe a little -stove for heating soldering-irons, and doing -other light work. It is made as follows, and -will be found very useful.</p> - -<p>Fig. 71, A, is a tube of sheet-iron, which forms the body -of the little stove. Four light iron rods stand out from it, -which form handles, but these are forked at the ends, and -thus become rests for the handles of soldering-irons, or any -light bars that are to be heated at the ends. Below is a -tray, also of sheet-iron, upon short legs to keep it off the -table—for this is a little table-stove. C is the cast-iron -grate. You can buy this for a few pence first of all, and -then you fit your sheet-metal to it. It will rest on three -or four little studs or projections riveted to the stove inside; -or you can cut three or four little places like D, not -cutting them at the bottom line, <i>a b</i>, but only on three -sides, and then bend in the little piece so as to make a<span class="pagenum"><a name="Page_326" id="Page_326">[326]</a></span> -shelf. If the stove is about 4 inches high above the grate, -and 2 or 3 inches below it, and 6 inches diameter, it will -be sufficiently large for many small operations; but that -the fuel may keep falling downwards as it burns, the lower -part should be larger than the upper, and, to admit plenty -of air, should be cut into legs as shown. Round the top -are cut semicircular hollows, in which the irons rest. To -increase the heat, a chimney or blower, B, is fitted, which -has also openings cut out to match those of the lower part, -so that the soldering-irons can be inserted when this -chimney is put on. If, however, this is not required, but -only a strong draught, by turning the chimney a little, all -the openings will be closed. A still longer chimney can -be added at pleasure. A hole should be made at the level -of the grate to admit the nozzle of an ordinary pair of bellows. -This stove you would find of great service, and it -may be fed with coke and charcoal in small lumps. Now -you <i>may</i> make the above far more useful. It will make a -regular little furnace, and not burn through, if you can line -it with fireclay. In London and large towns you can -obtain this; and it only needs to be mixed up with water, -like mortar, when you can plaster your stove inside an inch -thick or more, making it so much larger on purpose. -There is no need to do this below the level of the grate; -but if you cannot get fireclay, you may do almost as well -by getting a blacklead-meltingpot from any ironfoundry,<span class="pagenum"><a name="Page_327" id="Page_327">[327]</a></span> -and boring a few holes round the bottom for air, and fitting -it inside your little iron stove. In this you can obtain -heat enough to melt brass, and it will last a great deal -longer than the iron alone, which will burn through if you -blow the fire much; but for general soldering, tempering -small tools, and so forth, you need not blow the fire, as -the hood and chimney will sufficiently increase the heat. -There is no danger in the use of this little fireplace, but -of course you would not stand it near a heap of shavings, -unless you are yourself a very careless young “shaver.”</p> - -<div class="figcenter" style="width: 400px;" id="fig71"> -<img src="images/figure71.jpg" width="400" height="275" alt="" /> -<p class="caption">Fig. 71.</p> -</div> - -<h3>HOW TO TEMPER TOOLS.</h3> - -<p>There is no reason why the young mechanic should not<span class="pagenum"><a name="Page_328" id="Page_328">[328]</a></span> -be told how to make his own tools, and how to harden and -temper them, because he ought to be a sort of jack-of-all-trades; -and perhaps he may break a drill or other small -tool just in the middle of some special bit of work, or his -drill may be just a little too small or too large, and there -he will be stuck fast as a pig in a gate, and unable to set -himself right again any more than the noisy squeaker -aforesaid. But to a workman a broken drill means just -five minutes’ delay, and all goes on again as merrily as -before; and as we wish to make our young readers workmen -and not bunglers, we will teach them this useful art -at once.</p> - -<p>Drills are made of steel wire or rods of various sizes. -In old times they were made square at one end, to fit lathe-chucks -or braces, but now, for lathe-work, they are generally -made of round steel, and fastened into the chuck with -a set screw on one side. In this way they can be more -easily made to run true. But there are so many kinds of -drills that I suppose I had better go into the matter a -little—only I have not room to say much more.</p> - -<div class="figcenter" style="width: 500px;" id="fig72"> -<img src="images/figure72.jpg" width="500" height="425" alt="" /> -<p class="caption">Fig. 72.</p> -</div> - -<p>Look at Fig. 72, and you will see some of the more usual -forms of drills used, but these are by no means all. You -will not indeed require such a collection; and yet, if you -should grow from a young mechanic into an old one, I daresay -you will find yourself in possession of several of them. -The first, labelled 1, is the little watchmaker’s drill, of<span class="pagenum"><a name="Page_329" id="Page_329">[329]</a></span> -which, nevertheless, this would be considered a very large -size. It is merely a bit of steel wire, with a brass pulley -upon it, formed into a point at the largest end, and into a -drill at the other. The way it is worked is this: At the -side of the table-vice—that is, at the end of its jaws or -chops or chaps—are drilled a few little shallow holes, in -which the watchmaker places the point at the thickest end; -the drill-point rests against the work, which he holds in -his left hand. A bow of whalebone, <i>a</i>, has a string of -fine gut such as is used for fishing, or, if the drill is very -small, a horse-hair; and this is given one turn round the<span class="pagenum"><a name="Page_330" id="Page_330">[330]</a></span> -brass pulley before the drill is placed in position. The -bow is then moved to and fro, causing the drill to revolve -first in one direction and then in the other. The general -work is in thin brass, and therefore these little tools are -sufficiently strong for the purpose. Some of the drills and -broaches (four or five, or even six sided wires of steel) are -so fine that they will bend about like a hair, and yet are -so beautifully made and tempered as to cut steel.</p> - -<p>No. 2 is a larger drill, even now much used. In principle -it is exactly similar to the last, but the pulley is -replaced by a bobbin or reel of wood, made to revolve by a -steel bow with a gut string, or a strong wooden bow. The -drills, too, are separate, and fit into a socket at the bottom -of the drill-stock. The large end is pointed, as in the last, -and is made to rest in one of the holes in a steel breast-plate, -<i>b</i>, which is tied to the chest of the operator, who, by -leaning against it, keeps the drill to its work, while both -hands are free to hold the latter steady. There is a modification -of this tool, invented by a Mr Freeman, intended -to do away with the bow. The bobbin or reel is turned -without raised ends, and is worked by a flat strip of -wood covered with india-rubber, and turned at one end to -form a convenient handle. The having to twist the bow-string -round the drill, which is always a bother, is thus -done away with.</p> - -<p>No. 4 is a drill-stock similar to the last, but in place of<span class="pagenum"><a name="Page_331" id="Page_331">[331]</a></span> -the breast-plate a revolving head or handle is put to the -top, in which the point works. This is held in one hand, -while the drill-bow is worked by the other. This is also -generally held against the chest, as the hand alone does -not give sufficient pressure. Heavy work, however, cannot -well be done by these breast-drills, and they are liable -to cause spitting of blood from the constant pressure in -the region of the heart and lungs.</p> - -<p>No. 3 is the Archimedean drill-stock, now very common, -but originally invented by a workman of Messrs Holtzappffel’s, -the eminent lathemakers of London. It now -comes to us as an American drill-stock. It is a long -screw of two or more threads, with a ferule or nut working -upon it. The upper end revolves within the head, which is -of wood; the lower end is formed into a socket to receive -the drills, which revolve by sliding the ferule up and down. -Some are 14 inches long, and others not more than 5. -The first are used with the pressure of the chest, the latter -with that of the left hand. For light work these are very -useful, and you will seldom need any other in the models -of small engines, &c.</p> - -<p>No. 5 is another watchmaker’s drill, but serves also as a -pin-vice to hold small pieces of wire while being turned or -filed in the little lathes which are used in that trade, and -which are worked by a bow with one hand, while the tool -is held in the other. This is by no means a useless tool,<span class="pagenum"><a name="Page_332" id="Page_332">[332]</a></span> -even without the pulley. It is made by taking a round -(or better, an octagon, or five or six sided) piece of steel, -drilling the end a little distance, and then sawing the -whole up the middle. The slit thus made is then filed -away to widen it, and leave two jaws at the end, which -grasp the pin or drill; a ring slips over, and keeps the -jaws together.</p> - -<p>We now come to fig. 6, which represents the best of all -drills for metal. It is <i>really</i> American this time, and does -our Transatlantic cousins great credit, as does the machinery -generally invented or made by them (the Wheeler and -Wilson sewing-machines for instance). The steel of which -this drill is made is accurately turned in a lathe, and the -spiral groove is cut by machinery. This groove acts in two -ways—first, as allowing the <i>shavings</i> (<i>not powdery chips</i>) to -escape as the tool penetrates, but as forming the cutting -edges where they (for there are two) meet at the point. -These, however, require a lathe with a self-centring chuck -made on purpose. They are sold in sets upon a stand, -chuck and all complete, and each is one-thirty-second of -an inch larger than the other. Some are as small as a -darning-needle, or less, and they run up to an inch or so in -diameter. There are large and small sets.</p> - -<p>We now pass to the old-fashioned smith’s brace, fig. 7, -shown in position, drilling the piece <i>e</i>. Pressure is kept -up either by a weighted lever, or by a screw, as shown<span class="pagenum"><a name="Page_333" id="Page_333">[333]</a></span> -here. The brace is moved round by the hand of the workman. -Very often this tool is arranged on the vice-bench, -so that the work can be retained in the jaws of the vice -while being drilled. Sometimes it is mounted on a separate -stand, having a stool below, and a special kind of vice -or clamp is added. Well made, this is not so bad a tool as -it looks, but those used ordinarily in smiths’ shops are very -clumsy, and do not even run true, and the drills are badly -made, although by sheer force they are driven through the -work.</p> - -<p>Whatever form of drill-stock is used, the main thing is -to have the drills properly formed. You will recognise <i>k</i> -and <i>n</i> as common forms, than which <i>m</i> is considerably -better. For cast-iron <i>n</i> would not be a bad point, because -the angle is great, much greater, you see, than <i>k</i>; and the -bevels which form the cutting edges of a drill should also -not be too sharp, as they are generally made, for, as they -only scrape away the metal, their edges go directly.</p> - -<p>The common way to make a drill is this: A piece of steel -wire of the required size is heated until red hot (never to -a <i>white</i> heat, or it would be spoiled). The end is then -flattened out with a hammer, and the point trimmed with -a file. It is then again heated red hot, and dipped into -cold water for a second. Then held where the changes of -colour, which ensue as it cools, can be seen plainly; and as -soon as a deep yellow or first tinge of purple becomes<span class="pagenum"><a name="Page_334" id="Page_334">[334]</a></span> -visible, it is entirely cooled in water. It is then finished, -except as regards fitting it to the drill-stock, which may be -done before or after it is hardened, because care is taken -only to dip the extreme point. To get proper cutting -edges the drill is taken to the grindstone, and each side of -the point is slightly bevelled, but in opposite directions, so -as to make it cut both ways. It is not, however, left of -equal width, like <i>o</i>, but the flattened sides are ground away, -so as to make more of a point, like <i>p</i> and <i>n</i>.</p> - -<p>Now, this is all right enough as regards forging and -hardening, and tempering, and for the <i>smallest</i> drills this -is the only way to make them. (Only watchmakers heat -them in the candle till red, and then cool and temper by -running them into the tallow.) But if you want a good -drill that will cut well and truly, you should file away the -sides of a round bar like <i>m</i>, only spreading the point very -slightly indeed, just to prevent the drill sticking fast in the -work. Another drill, indeed, is spoken of very highly, -which is also carefully made like <i>m</i>, but the places which -are here flat are hollowed out or grooved lengthwise, the -section of the point—<i>i.e.</i>, the appearance of the <i>end</i> of the -drill—becomes rather curious, like <i>r</i>. I am assured by those -who have used them, that these cut quite as well as the -twist drills which I have described already. These which -I am now speaking of are also American; and I don’t know -how it is, that somehow America is a far better place for<span class="pagenum"><a name="Page_335" id="Page_335">[335]</a></span> -improvements in tools and machines than our own Old -England. And if I had a wonderful invention—a new -birch-rod-making and flogging-machine for very troublesome -boys, for instance—I am afraid I should go to America -to patent it; but I daresay English boys would not object -to that.</p> - -<div class="poetry-container"> -<div class="poetry"> -<div class="stanza"> -<div class="verse">To teach an idle boy to read,</div> -<div class="verse indent1">His mind be sure to jog;</div> -<div class="verse">But if he’s very bad indeed,</div> -<div class="verse indent1">You’ll be obliged to flog.</div> -</div> -<div class="stanza"> -<div class="verse">Yet if you flog him day by day,</div> -<div class="verse indent1">He’ll <i>never</i> learn to read;</div> -<div class="verse">For boys require a lot of play</div> -<div class="verse indent1">To make them work with speed.</div> -</div> -<div class="stanza"> -<div class="verse">But young mechanics, if they err</div> -<div class="verse indent1">Or join the lazy team,</div> -<div class="verse">Would all, as I suppose, prefer</div> -<div class="verse indent1">To be well flogged by steam.</div> -</div> -</div> -</div> - -<p>If not, they had better not let me patent my flogging-machine. -Luckily it is not invented yet.</p> - -<p>The <i>cutting edges</i> of drills come under the same rules as -other cutting edges. You might, for instance, hold a large -drill flat on the rest, and use either edge as a turning-tool. -You will see at once that these edges will not cut if -made in the usual way, but only scrape. The bevel wants -to be ground only to 3°, as before explained, to give -the proper clearance, and the cutting edge requires to be -then made by grinding back the <i>upper</i> surface, which is -just the same in effect as is produced by twisting the metal<span class="pagenum"><a name="Page_336" id="Page_336">[336]</a></span> -or cutting a spiral groove, which hollows out this upper -surface and gives it cutting power. It is no use grinding a -sharper-looking bevel, or making more of a point—you -only weaken the edge; <i>m</i> or <i>n</i> is quite pointed enough, -though the first is a right angle and the second greater; -and, for cast-iron, a rounded point, showing no angle at all, -will do just as well, or better, when once it has begun to -penetrate. Do not be deceived, therefore, by making drills -look pointed and keen, for, I repeat, they are scraping tools -only, unless you file an edge by bevelling back the upper -face of each side of the point. If you were to make a very -thick, strong drill, you might begin by grinding back the -two sides to 3°, to form the accidental front line of the point -or section angle, and then grind back, <i>at 45° from this line</i>, -the upper face, by which you would do just what you did to -give the graver cutting edges of 60°—only a drill thus -formed must have a point of 90°. It would cut in two -directions, like one for a drill stock and bow.</p> - -<p>I hope my bigger boys will not pass over the remarks on -cutting edges interspersed in this book, for, once understood, -they will be found to be most valuable. Indeed, they -cannot work intelligently until they understand exactly -the nature and principles of the tools which they have to -use. In drilling iron, use water or oil, or soap and water, -or soda-water—either will do; but the holes are drilled in -the ships’ armour-plating with soap and water to cool the<span class="pagenum"><a name="Page_337" id="Page_337">[337]</a></span> -drill; and very well it answers, for these plates are several -inches thick, but the holes are soon made. When working -in brass and gun-metal, use no water, but work the drill -quite dry. The same rules, in short, apply to drilling as -to turning or planing metal; and if you could see the -action of a well-made American twist-drill, you would recognise -this similarity, for you would see the metal come -forth in long, bright curls, as pretty and shining as those -of your favourite young lady or loving sister—<i>one</i> of which -you have, I daresay.</p> - -<p>To give you some idea of what a straight course a drill -will take, if rightly made and skilfully used, I may tell you -that a twist-drill has been run through a lucifer-match -from end to end without splitting it; and as to the <i>fineness</i> -possible, I have seen a human hair with an eye drilled -through it, by which, needle-like, it was threaded with the -other end of itself.</p> - -<p>I told you how to bore a cylinder, which is but drilling -on a larger scale, and in Fig. 65 I sketched the method of -doing this in the lathe with a rosebit. But I did not explain -another tool used just in the same way, but which will -bore holes in solid iron wonderfully. Fig. 65, L, H, K, is -one of these. This is an engineer’s boring-bit, and is made -of all sizes, from that required to bore the stem of a tobacco-pipe—(don’t -smoke, boys, it will dry up your brains)—to -that which would bore a cannon. A rod of steel is forged<span class="pagenum"><a name="Page_338" id="Page_338">[338]</a></span> -with a boss or larger part at one end. This is centred in the -lathe, and the centre-marks are well drilled, and not merely -punched, especially that at the small end. The boss is then -turned quite cylindrical, after which it is filed<a name="FNanchor_4" id="FNanchor_4"></a><a href="#Footnote_4" class="fnanchor">[4]</a> away exactly -to the diametrical line, as you will see by inspection of L. -The end is then ground off a little slanting, to give, as -before, about 3° of clearance. The cutting edge thus obtained, -and the end in which the centre hole still remains, -are carefully hardened. You thus have a tool which will -bore splendidly, but you must give it entrance by turning -a recess first of all in the work, or drilling, with a drill of -equal size, a little way into the material. Used like the -rosebit, this tool will run beautifully straight, so that you -can bore very deep, long holes with it, and cylinders can -be most beautifully bored with it. I think you would be -able to make these tools with a little care; but, when you -harden them, only heat and dip the extremities, or it is -ten to one your steel rod will bend and warp in cooling, -and you will not be able to rectify it. If the ends are quite -hard, it is as well that the rest should be soft, as the tool -will not then be so liable to get broken.</p> - -<p>There are many other tools used for boring iron and steel, -but you need not trouble yourself at present to learn anything -of them—they are no use to you now.</p> - -<p>I have headed this chapter “Hardening and Tempering”<span class="pagenum"><a name="Page_339" id="Page_339">[339]</a></span> -tools, but as yet I have only partially explained the process, -which is a very curious one; and though the <i>result</i> is highly -necessary in many cases, it is by no means well understood -what really takes place in the process, or why this effect -should occur in steel, but not in iron, or brass, or other -metals.</p> - -<p>If you heat a piece of bright steel over a clear gas jet or -fire which will not smoke it, you will see several colours -arise as the metal gets hotter and hotter, until finally it -becomes red. These are due to oxidation, which is so long -a word that I am not sure I can stop to explain it thoroughly. -Let us see, however, what we can make of it. The air we -breathe contains two gases, oxygen and nitrogen, with a -small proportion of a third called carbonic acid. Neither of -these <i>alone</i> will support life, or keep the fire burning, or -enable vegetables to live and grow, but it is the first which -is in this the chief support. The second is only used by -Nature as we use water to brandy, viz., to dilute it and -render it less strong. If we breathed oxygen alone, we -should live too fast, and wear out our bodies in a few hours. -If we breathed nitrogen only, we should die, and so of carbonic -acid. Now this oxygen seizes upon everything in a -wonderful and sometimes provoking manner. If you leave -a bright tool out of doors to get damp, down comes our -friend oxygen and rusts it. It combines with the iron and -makes oxide of iron, which is what we call rust. I suppose,<span class="pagenum"><a name="Page_340" id="Page_340">[340]</a></span> -however, this oxygen comes more from the water than the -air, because water is made also of two gases, hydrogen and -this same oxygen. It is certain that oxygen in this case -always finds any bright tools that we leave about in the wet, -and coats them with a red jacket very speedily. Then if -you look at a blacksmith at work, you will see scales fall -from the hot iron as he hammers it. These are black, but -our old friend has been at work, and united with the red-hot -metal and formed another oxide of iron, called black -oxide. We can understand this. If a man eats a good -deal, or drinks a good deal, he gets red in the face; if he eats -till he chokes himself, he gets black in the face, and I suppose -it is much the same when oxygen eats too much iron. -Well, when we begin to heat the steel, down comes oxygen -and begins his work; and first he looks very pale; then he -gets more bilious and yellower; then he gets hotter and -shows a tinge of red with the yellow forming orange; then -he begins to get purple, then blue, then deeper blue; and -finally black before he gets absolutely red and white hot.</p> - -<p>Now to temper steel, we first heat it red-hot, not minding -these colours, and then we cool it suddenly in cold water. -This renders it very hard indeed. No file will cut it, or -drill penetrate it; but if we strike it, behold it breaks like -glass! This is too hard for general work, for the edge will -break and chip if it meets with any hard spot in the metal, -or chances to bite in too deep. Its teeth are too brittle, and<span class="pagenum"><a name="Page_341" id="Page_341">[341]</a></span> -so get broken off. For this reason we have to “let down,” -or temper, the tool, and we proceed as follows: The part -to be tempered is ground quite bright. It is then laid upon -a bar of iron heated red-hot, or if small, it is held over a -gas jet or in a candle; heated, in short, in any way most -suitable and convenient. And now, first, our friend oxygen -puts on a pale yellow face as before. This will do for turning -steel and iron, but is still too hard for general work. -Then comes the orange, and this presently tends slightly to -blue; at which point, if the tool is instantly cooled in water, -it will be found to bear a good edge, hard, but sufficiently -tough for work. Most tools for metal and drills are let -down to something between the yellow and blue, and we -know that the more they approach blue, the softer they will -be. Thus we can easily manage our tools;—some to bear -hard blows, like axes, which are tempered to a blue colour; -some like files, which a blow will break, but which are -famous for their own special work—these are let down only -to a pale yellow; others, like springs and saws, are let -down to a more thorough blue, because they are required -to be elastic and tough, but are not needed to be so particularly -hard. Then tools like turnscrews, and bradawls, -and gimblets are left even softer, sometimes not tempered -or hardened at all, but just forged and ground to the required -shape.</p> - -<p>Now, I fancy some of my sharp boys will say that the<span class="pagenum"><a name="Page_342" id="Page_342">[342]</a></span> -first description I gave of the mode of hardening and tempering -was not exactly like this; nor was it, yet in -principle it is the same. For instance, if you give a -drill to a smith to make, he will do as I then said. He -will heat the extreme point red-hot, then dip the point in -water, give a rub on the stone or bricks of the forge, and -watch the colours. This can be done when the tool is of -sufficient substance to retain heat enough after the edge -has been dipped to <i>re-heat</i> that edge sufficiently. In this -case there is no need to chill the whole tool and then heat -it again. But in the case of small drills and tools, pen-knife-blades, -and other articles of this nature, there will -not be sufficient heat retained, after dipping, to bring up -to the surface the desired colours; for oxygen likes a -<i>hot</i> dinner as well as you do, and if the iron is not hot -enough he will have nothing to do with it.</p> - -<p>One great difficulty you would find if you had much -tempering to do, viz., that the articles bend under the -operation, some more than others. Try this: Take a thin -knitting-needle when the owner is not looking, and run off -with it;—it is all in the cause of science! Heat it red-hot, -and with a pair of pliers take it up and drop it <i>sidewise</i> in -a basin of water. It will bend like a bow. Heat again, -straighten it, re-heat, and this time pop it in lengthwise—endwise, -point first—I mean (don’t you see that a round -needle has <i>no sides</i>, and puts me into a perfect quagmire<span class="pagenum"><a name="Page_343" id="Page_343">[343]</a></span> -of difficulty). However, you will understand this, and -will find the needle not bent nearly so much as before, but -still it is not straight. As I explain most things as I go -on, I may as well explain why this bending occurs before -I tell you how to straighten your work again. All metals -expand with heat, and contract with cold. I am sure <i>I</i> -contract terribly in the winter until I have had plenty of -hot soup, and hot roast-beef, and plum-pudding; and I -know my <i>temper</i> improves, too, when I get expanded and -warm. Well now, when you dropped your sister’s knitting-needle -all hot on its side into the water, that side -contracted before the other, and consequently the needle -bent; but when you put it in the water, <i>end on</i>, it was -cooled all round at once, and if you could but cool a piece of -metal equally all over, inside and out, <i>at once</i>, all parts would -shrink equally fast, and the article would remain straight.</p> - -<p>But there is, unfortunately, another cause of this bending, -which is, that all articles are not of such form that -the same quantity of metal is on all sides of the axial -line. Take a half-round file, for instance; one side is flat, -the other curved, so that taking these two surfaces into -consideration, one contains a great deal more metal than -the other, and will not cool at the same rate. These -articles are far more liable to bend than those whose sides -are parallel. Another result of the hot mass being cooled -most quickly on the outside is, that cracks are produced in<span class="pagenum"><a name="Page_344" id="Page_344">[344]</a></span> -the latter, because, so to speak, the skin is contracted, and -can no longer contain all the expanded metal within it. -Hence, to make a mandrel for a lathe, it is common to bore -it out first, before hardening, to remove this mass of metal, -and to allow the water to touch it inside as well as out. -Such mandrels seldom crack or bend.</p> - -<p>The only way to straighten articles which have warped -by hardening, is by what is called hacking or hack-hammering, -which is nothing more than hammering the concave -or hollow side with the edge of the steel pane of a -hammer. This spreads the metal upon the hammered side, -and, by expanding it, straightens the tool, for the hollow -side, remember, is that which was too much shrunk or contracted. -This is not an operation you will have to do, -especially if you only harden the extreme points of the -drills and little tools you make.</p> - -<p>There is another way of hardening, not steel, but iron, -called “case hardening,” because it puts a case of steel -over the surface of the metal. Obtain a salt called prussiate -of potash. It is yellow, like barley-sugar, but is -poison. Heat the iron red-hot, and well rub it upon this -salt, and then cool it in water. You will find that now a -file will not touch it, its surface being as hard as glass. It -is carbonised on its exterior, and made into hard steel. -This can be done in another way, as gun-locks, snuffers, -and many other things are case hardened. They are enclosed<span class="pagenum"><a name="Page_345" id="Page_345">[345]</a></span> -in an iron box, with cuttings of leather and bone-dust, -and the box is luted about with clay and put in the -fire. All the pieces get red-hot, and the leather chars and -blackens, and some of it combines as before with the hot -iron, and makes it into steel. And our friend oxygen is -considerably at a loss in this case to find his way in, or he -would make black scales again and spoil the work; or combine -with the carbon (or charcoal) and make it into gas. -Probably, however, as we shut up a little oxygen with the -contents of the box, this change <span class="smcapuc">DOES</span> take place, but <i>just as -the gas rises the iron seizes it</i>, and holds it fast.</p> - -<p>And now, boys, I find it necessary to lay down the pen, -which I see has almost run away with me, and written a -good many more pages than I at first intended. Since I -began to write I have visited the workshops at King’s -College, and seen a sight to gladden my eyes. Boys carpentering, -boys turning, boys filing; engines of real use, -with single and double cylinders, finished, and in course of -construction, and all these the work of schoolboys, whose -hands and brains are alike engaged in this delightful -branch of industry. Let no one, therefore, pretend that -boys are not capable of executing good work of this kind in -a masterly manner, or that what they do is always child’s-play, -or I shall take up the cudgels in their behalf. I -have also seen, in the Working-Men’s Exhibition, a very -neat little engine, made by a boy only twelve years of age,<span class="pagenum"><a name="Page_346" id="Page_346">[346]</a></span> -which makes me hope and believe that the few hints upon -wood and metal work which I have here thrown together -will neither be unacceptable nor useless to those whom I -address in these pages. In this hope I take my leave, and -sign myself, with gratification and pride—</p> - -<p class="center">The boy mechanic’s faithful friend,</p> - -<p class="right">THE AUTHOR.</p> - -<div class="figcenter" style="width: 275px;"> -<img src="images/footer4.jpg" width="275" height="125" alt="" /> -</div> - -<hr /> - -<div class="footnotes"> - -<h2>FOOTNOTES</h2> - -<div class="footnote"> - -<p><a name="Footnote_1" id="Footnote_1"></a><a href="#FNanchor_1"><span class="label">[1]</span></a> In the drawing, they are all accidentally drawn of the same pitch.</p> - -</div> - -<div class="footnote"> - -<p><a name="Footnote_2" id="Footnote_2"></a><a href="#FNanchor_2"><span class="label">[2]</span></a> The parts so jointed are highly exaggerated; when hammered down, the -joint only forms a light beading.</p> - -</div> - -<div class="footnote"> - -<p><a name="Footnote_3" id="Footnote_3"></a><a href="#FNanchor_3"><span class="label">[3]</span></a> The bottom joint must therefore be hammered close; the upper one will -become a ledge for the boiler to rest on.</p> - -</div> - -<div class="footnote"> - -<p><a name="Footnote_4" id="Footnote_4"></a><a href="#FNanchor_4"><span class="label">[4]</span></a> In large tools this is not done by the file.</p> - -</div> - -</div> - -<hr /> - -<div class="figcenter" style="width: 500px;"> -<img src="images/header6.jpg" width="500" height="110" alt="" /> -</div> - -<p class="center larger">Heroes of the Nations.</p> - -<p class="center">EDITED BY<br /> -EVELYN ABBOTT, M.A., <span class="smcap">Fellow of Balliol College, Oxford</span>.</p> - -<p>A series of biographical studies of the lives and work -of a number of representative historical characters about -whom have gathered the great traditions of the Nations -to which they belonged, and who have been accepted, in -many instances, as types of the several National ideals. -With the life of each typical character will be presented -a picture of the National conditions surrounding him -during his career.</p> - -<p>The narratives are the work of writers who are recognized -authorities on their several subjects, and, while -thoroughly trustworthy as history, will present picturesque -and dramatic “stories” of the Men and of the events connected -with them.</p> - -<p>To the Life of each “Hero” will be given one duodecimo -volume, handsomely printed in large type, provided -with maps and adequately illustrated according to -the special requirements of the several subjects. The -volumes will be sold separately as follows:</p> - -<table summary="Prices of the volumes"> - <tr> - <td>Cloth extra</td> - <td class="tdr">$1 50</td> - </tr> - <tr> - <td>Half morocco, uncut edges, gilt top</td> - <td class="tdr">1 75</td> - </tr> - <tr> - <td>Large paper, limited to 250 numbered copies for - subscribers to the series. These may be obtained - in sheets folded, or in cloth, uncut edges</td> - <td class="tdr">3 50</td> - </tr> -</table> - -<p>The first group of the Series will comprise twelve -volumes, as follows:</p> - -<div class="hanging"> - -<p><b>Nelson, and the Naval Supremacy of England.</b> By <span class="smcap">W. Clark -Russell</span>, author of “The Wreck of the Grosvenor,” etc.</p> - -<p><b>Gustavus Adolphus, and the Struggle of Protestantism for Existence.</b> -By <span class="smcap">C. R. L. Fletcher</span>, M.A., late Fellow of All Souls College, -Oxford.</p> - -<p><b>Pericles, and the Golden Age of Athens.</b> By <span class="smcap">Evelyn Abbott</span>, M.A., -Fellow of Balliol College, Oxford.</p> - -<p><b>Theodoric the Goth, the Barbarian Champion of Civilization.</b> By -<span class="smcap">Thomas Hodgkin</span>, author of “Italy and Her Invaders,” etc.</p> - -<p><b>Sir Philip Sidney, and the Chivalry of England.</b> By <span class="smcap">H. R. Fox-Bourne</span>, -author of “The Life of John Locke,” etc.</p> - -<p><b>Julius Cæsar, and the Organization of the Roman Empire.</b> By -<span class="smcap">W. Warde Fowler</span>, M.A., Fellow of Lincoln College, Oxford.</p> - -<p><b>John Wyclif, Last of the Schoolmen and First of the English Reformers.</b> -By <span class="smcap">Lewis Sargeant</span>, author of “New Greece,” etc.</p> - -<p><b>Napoleon, Warrior and Ruler, and the Military Supremacy of -Revolutionary France.</b> By <span class="smcap">W. O’Connor Morris</span>, sometime -Scholar of Oriel College, Oxford.</p> - -<p><b>Henry of Navarre, and the Huguenots in France.</b> By <span class="smcap">P. F. Willert</span>, -M.A., Fellow of Exeter College, Oxford.</p> - -<p><b>Alexander the Great, and the Extension of Greek Rule and of -Greek Ideas.</b> By Prof. <span class="smcap">Benjamin I. Wheeler</span>, Cornell University.</p> - -<p><b>Charlemagne, the Reorganizer of Europe.</b> By Prof. <span class="smcap">George L. Burr</span>, -Cornell University.</p> - -<p><b>Louis XIV., and the Zenith of the French Monarchy.</b> By <span class="smcap">Arthur -Hassall</span>, M.A., Senior Student of Christ Church College, Oxford.</p> - -</div> - -<p>To be followed by:</p> - -<div class="hanging"> - -<p><b>Cicero, and the Fall of the Roman Republic.</b> By <span class="smcap">J. L. Strachan -Davidson</span>, M.A., Fellow of Balliol College, Oxford.</p> - -<p><b>Sir Walter Raleigh, and the Adventurers of England.</b> By <span class="smcap">A. L. -Smith</span>, M.A., Fellow of Balliol College, Oxford.</p> - -<p><b>Bismarck. The New German Empire: How It Arose; What It -Replaced; and What It Stands For.</b> By <span class="smcap">James Sime</span>, author of -“A Life of Lessing,” etc.</p> - -<p><b>William of Orange, the Founder of the Dutch Republic.</b> By <span class="smcap">Ruth -Putnam</span>.</p> - -<p><b>Hannibal, and the Struggle between Carthage and Rome.</b> By -<span class="smcap">E. A. Freeman</span>, D.C.L., LL.D., Regius Prof. of History in the -University of Oxford.</p> - -<p><b>Alfred the Great, and the First Kingdom in England.</b> By <span class="smcap">F. York -Powell</span>, M.A., Senior Student of Christ Church College, Oxford.</p> - -<p><b>Charles the Bold, and the Attempt to Found a Middle Kingdom.</b> -By <span class="smcap">R. Lodge</span>, M.A., Fellow of Brasenose College, Oxford.</p> - -<p><b>John Calvin, the Hero of the French Protestants.</b> By <span class="smcap">Owen H. -Edwards</span>, Fellow of Lincoln College, Oxford.</p> - -<p><b>Oliver Cromwell, and the Rule of the Puritans in England.</b> By -<span class="smcap">Charles Firth</span>, Balliol College, Oxford.</p> - -<p><b>Marlborough, and England as a Military Power.</b> By <span class="smcap">C. W. V. -Oman</span>, A.M., Fellow of All Souls College, Oxford.</p> - -</div> - -<p class="center">G. P. PUTNAM’S SONS</p> - -<p class="center">NEW YORK<br /> -27 WEST TWENTY-THIRD ST.</p> - -<p class="center">LONDON<br /> -24 BEDFORD ST., STRAND</p> - - - - - - - - -<pre> - - - - - -End of the Project Gutenberg EBook of The Young Mechanic, by James Lukin - -*** END OF THIS PROJECT GUTENBERG EBOOK THE YOUNG MECHANIC *** - -***** This file should be named 60765-h.htm or 60765-h.zip ***** -This and all associated files of various formats will be found in: - http://www.gutenberg.org/6/0/7/6/60765/ - -Produced by Chris Curnow and the Online Distributed -Proofreading Team at http://www.pgdp.net (This file was -produced from images generously made available by The -Internet Archive) - -Updated editions will replace the previous one--the old editions will -be renamed. - -Creating the works from print editions not protected by U.S. copyright -law means that no one owns a United States copyright in these works, -so the Foundation (and you!) can copy and distribute it in the United -States without permission and without paying copyright -royalties. 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