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Title: A Manual of the Hand Lathe Comprising Concise Directions for Working Metals of All Kinds, Ivory, Bone and Precious Woods Author: Egbert Pomeroy Watson Release Date: February 6, 2015 [EBook #48179] Language: English Character set encoding: UTF-8 *** START OF THIS PROJECT GUTENBERG EBOOK A MANUAL OF THE HAND LATHE *** Produced by deaurider, David Maranhao and the Online Distributed Proofreading Team at http://www.pgdp.net (This file was produced from images generously made available by The Internet Archive) Transcriber's Note: The cover image was created by the transcriber and is placed in the public domain. A M A N UA L OF THE H A N D L A T H E : COMPRISING CONCISE DIRECTIONS FOR WORKING METALS OF ALL KINDS, IVORY, BONE AND PRECIOUS WOODS; DYEING, COLORING, AND FRENCH POLISHING; INLAYING BY VENEERS, AND VARIOUS METHODS PRACTICED TO PRODUCE ELABORATE WORK WITH DISPATCH, AND AT SMALL EXPENSE. B Y E G B E RT P. WAT S O N , LATE OF “THE SCIENTIFIC AMERICAN,” AUTHOR OF “THE MODERN PRACTICE OF AMERICAN MACHINISTS AND ENGINEERS.” ILLUSTRATED BY SEVENTY-EIGHT ENGRAVINGS. PHILADELPHIA: HENRY CAREY BAIRD, INDUSTRIAL PUBLISHER, 406 WALNUT STREET. LONDON: SAMPSON LOW, SON & MARSTON, Crown Buildings, 188 Fleet St. 1869. 1 Entered according to Act of Congress, in the year 1869, by HENRY CAREY BAIRD, In the Clerk’s Office of the District Court of the United States, in and for the Eastern District of Pennsylvania. 2 TO MY DEAR SON, EGBERT PERLEY WATSON, I DEDICATE THIS LITTLE BOOK, IN THE HOPE THAT HE MAY BE A GOOD MAN, AND A GOOD MECHANIC. 3 5 P RE FACE. I did not write this little book with the intention of apologizing to the prospective reader, so soon as I had done so, but with the honest, I hope not egotistical, feeling that I had something to say that was not generally known. We live to learn and to impart what we know to others, and I have taken this method of giving my experience in a pastime that is elevating, artistic in every sense of the word, and a wholesome relief from the cares of business. In regard to the work itself, I can show samples of every thing of any importance described or given in it. I have not made all of the patterns given in the back part, for that is mere routine, but in gross, and in most details, the book is the result of experience, and will be found reliable as far as it goes. That it does not cover every possible change and use to which the lathe can be put, I am well aware. Something must be left for the workman to find out himself. Neither have I given any recipes for varnishes, for those cannot be made by inexperienced persons. Moreover, they can be had so cheaply and universally, that it is mere folly for any amateur to make them. Saluting all persons who love the art of which this little volume is descriptive, I am their sincere friend, EGBERT P. WATSON. New York, April 15, 1869. 6 7 CONTE NTS. PAGE CHAPTER I. The Foot Lathe 13 CHAPTER II. Tools 22 CHAPTER III. Scrapers, etc 30 Chasing and Screw Cutting 33 CHAPTER IV. Chasers, etc 35 CHAPTER V. Chucking 42 CHAPTER VI. Metal Spinning 51 CHAPTER VII. Ornamental Cutting 59 To Make a Pair of Solitaire Sleeve Buttons 59 CHAPTER VIII. Centres 65 CHAPTER IX. Fancy Turning 71 CHAPTER X. Ornamental Woods 77 Varieties 77 Snake Wood 78 Tulip Wood 79 Granadilla 80 Tamarind 80 Cam Wood 81 Box Wood 81 Laurel Root 82 White Holly 82 Ebony 82 Olive Wood 83 Sandal Wood 83 Rose Wood 84 Curled Maple 84 Birds’ Eye Maple 84 Treatment 85 8 CHAPTER XI. Wood Turning 87 CHAPTER XII. Tools for Wood Turning 90 CHAPTER XIII. Tool Tempering, etc. 92 CHAPTER XIV. Artistic Wood Turning 96 CHAPTER XV. Stamp Inlaying 102 CHAPTER XVI. Designs in Mosaic 106 CHAPTER XVII. Finishing the Outside 110 CHAPTER XVIII. Inlaying Continued 114 Gluing in Veneers 115 Ivory 116 Polishing 118 Dyeing Ivory 118 CHAPTER XIX. Ornamental Designs for Inlaying 121 CHAPTER XX. General Summary 125 Lacquers 126 Soldering 127 Varnishing and Polishing 129 Brushes 131 Pearl 131 Miscellaneous Tools 131 Curving Veneers 132 Cutting Miscellaneous Materials 133 Index 135 9 MANUAL OF THE HAND LATHE. CHAPTER I. THE FOOT LATHE. There are two distinct kinds of work done in foot lathes—the useful and the merely ornamental. Both afford enjoyment and profit to those who practise them. The mechanic who earns his living by working ten hours a day in a workshop, does not care to go home and pursue the same calling in the evening; but he can institute an agreeable change in his life, beautify his dwelling, and cultivate his taste, by the use of the lathe, and thus obtain ornaments that would cost large sums if purchased at the stores; or he may, indeed, make the lathe a source of revenue, and sell the product of his skill and ingenuity at high prices to those who admire, but have not the ability to construct. To many mechanics, even, the lathe is merely a machine for turning cylinders or disks, or executing beads, ogees, scrolls, or curves of various radii, so that, after all, the work is pretty much alike, and ceases to be attractive. This is quite a mistaken view. There are no such goods in market as those made on lathes, and peculiar tools used in connection with them—by lathes with traversing mandrels, with geometric chucks, with dome chucks, and compound slide rests. There are lathes that, while one could chase up a five-eight bolt in them as well as on the simple pulley and treadle machine, are also capable of executing all sorts of beautiful things—vases with bases nearly square, or exactly square, with round tops and hexagonal bodies, with gracefully-curved angular sides and bases, fluted vertically; boxes with curious patterns, resembling basket work; in fact, any combination of straight and curved lines, cut in the sides, it is possible for an ingenious man to invent. Strictly speaking, these are not lathes, for in order to do the things before mentioned it is necessary to use after attachments in connection with them, so that the combination of them produces the results spoken of. There is, absolutely, an unlimited field for the genius of workmen to exert itself in designing patterns and executing work of an ornamental character. All ornamental work resolves itself into movements of three kinds—angular, circular and straight. From the combination of these with each other, the times where they merge and emerge, where a movement of one kind changes into any other, where an ellipse becomes part of a circle, where circles are generated across the circumferences of other circles, where these patterns are drawn over and upon each other without destroying the character of either—we say, by such movements, and many others which it would be confusing to follow, the most beautiful forms are made. Or, if the taste of the workman runs upon mechanical instead of artistic things, there are steam engines to be made, steam boilers to be spun up, of small size; in fact, any piece or machine that can be thought of. It is almost unnecessary to specify the innumerable kinds of work that can be done in a hand lathe, but the amateur who delights in metal turning may make trinkets of all kinds for his friends, that shall vie in beauty with the best efforts of the jeweler and goldsmith. This, of course, is dependent on the material used, the taste of the workman, and his originality of conception. Pins for ladies’ wear can be made of boxwood and ebony, glued together in sections, of all designs, and afterwards turned in beads and mouldings, or otherwise ornamented in a chuck, as will be shown hereafter. Sleeve buttons can be made of ebony and silver, ivory and silver, pearl and gold, or any combination that is desired. Chess and checker men also afford a chance to display skill. And, besides these, special work of any nature is within the capacity of the machine. There is no family in this country that would not find it economy to have a foot lathe in the house, where the members have mechanical tastes—not necessarily the male members, for ladies use foot lathes, in Europe, with the greatest dexterity. Some of the most beautiful work ever made, was by Miss Holtzapfel, a relative of the celebrated mechanist of the same name. If there are shovels to be mended, the lathe will drill the holes and turn the rivets. If the handle of the saucepan is loose, it will do the same. If scissors or knives want grinding, there is the lathe; if the castors on the sofa break down, there is the lathe; if skates need repairs, either of grinding or of any other kind, there is the lathe. In short, it ought to be as much a part of domestic economy as the sewing machine, for it takes the odd stitches in the mechanical department that save money. Let not the inexperienced reader, who hears of a lathe for the first time, be frightened at this array of terms, or diverted from the use of it by the recital. In its simple form, as shown in Fig. 1, it is readily understood, and, after a little practice, easily managed by any one, and, after the first few weeks, the amateur will realize the fruits of his application. Fig. 1. 13 14 15 16 17 At first, it had not even a continuous rotary motion, but the spindle was driven by a belt worked by a spring pole or its equivalent. The belt was rolled round the spindle, and the pole allowed to spring up; the spindle then revolved the length of the belt, or rope, for belts were not thought of, and the operation was repeated, the work being done only when the force of the spring pole revolved the spindle and the job the right way. Foot lathes had, prior to the introduction of the engine lathe, been used on very heavy work. It is but a few years, comparatively speaking—not twenty—since cast-iron shafts, six, eight, and ten inches in diameter, were turned in such lathes. For all that we know to the contrary, many jobs, far exceeding this in size, have been thus executed. In some shops, there are still standing heavy oaken shears, made of timber twenty inches deep, and four or six inches wide, faced with boiler iron, and in the racks above there are long-shanked tools, with which the men of old were wont to do the work. These lathes are never used now, except for drilling holes, or for apprentices to practice on, but they serve to show what machinists had to do in olden times, when there were no vise benches to sit on and watch the chips curling off the tool, as men do now. Fig. 2. Hand lathes are not in great favor in large machine shops. They are not used, or should not be, for any purpose except drilling, and then they are no longer hand lathes, but horizontal drilling machines. There is no simple work to be done on a hand lathe that could not be performed to better advantage and more cheaply on a machine constructed for the purpose. Some large machine shops keep a hand lathe going continually, cutting off stud bolts, facing and rounding up nuts, and similar work. This does not seem profitable. A machine to do this work would do more, of a better quality, than hand labor could. The foot lathe—the terms hand and foot lathe are synonymous—is generally used, at the present time, by small machinists, manufacturers of gas fixtures, amateurs, etc.; men who do not work a lathe constantly, but are called off to braze or solder, or, perhaps, to fit some detail with a file. For these uses the foot lathe is one of the cheapest of tools; for the same person that does the work furnishes the power also, so that a man working on a foot, or hand lathe, as it is often called, ought to have first-class wages. Moreover, a first-rate foot lathe turner is always a good mechanic, for it takes no small degree of dexterity to perform the several jobs with ease, and dispatch, and certainty. To always get hold of the right tool, to use the same properly, so that it will last a reasonable time without being ground or tempered, to rough-turn hollow places with a square edge, to chase a true thread to the right size every time, without making a drunken one, or a slanting one, to make a true thread inside of an oil cup or a box—all these several tasks require good judgment, dexterity, and a steady hand. Of course, where a slide-rest is used, the case is different. We allude, specially, to a cutting tool managed by the hand. To do all these things, however, it is necessary to have tools, and good ones, or none. It is an old saying, that a bad workman quarrels with his tools, but a good workman has a right to quarrel with bad tools, if he is furnished with them, through chance or design. It is impossible to execute good work with a dull tool, one badly shaped, or unsuited to the purpose, and, therefore, it is important to set out right at the beginning. There is no tool more efficient in the hands of a good workman, than the diamond point, Fig. 2, here shown. For roughing off a piece of metal, for squaring up the end, for facing a piece held in the chuck, for running out a curve, or rounding up a globe, it is equally well adapted. It may be truly called the turner’s friend. 18 19 20 21 22 CHAPTER II. TOOLS. Any one who has watched a novice at work on a lathe, must have remarked the difficulty he has in controlling the tool and keeping up the motion of the treadle at the same time. The two operations are difficult to “get the hang of,” to use a homely phrase; but once conquered, the work can proceed. The natural tendency is to slack up or stop the motion of the treadle while the tool is engaged, and the tool is, therefore, at one time under the work, at another time above it, at another jumping rankly in, until, finally, the piece goes whirling out of the center or the chuck, and the operator flushes all over at his awkwardness. This, of course, is remedied by practice; and as this work is written mainly for the information of beginners and amateurs, we hope that experts and those who know all about hand lathes, will excuse allusion to such simple things as holding the tool properly, and kindred matters. The lathe must be of such a height as the workman finds convenient, so that he is not obliged to stoop much, and, at the same time, low enough to allow the weight of the body to be thrown on the tool when hard work is to be done. The speed of the lathe ought to be very high on the smallest cone, and there should be three speeds, at least, for different work. The object is to regulate the velocity of the work in the lathe, and keep the motion of the treadle uniform, as near as may be, at all times. It distresses a workman greatly, when chasing a fine thread on a small diameter, if he has to tread fast to get up the proper speed, as he does when there are only two speeds. On the contrary, for larger jobs, it is difficult to keep up a rotary motion if the foot moves slowly, as it must in order not to burn the tool by a high velocity on some kinds of work. Foot lathes, in general, are not geared, although some are, and ought to have wider ranges of speed than they do. Where one class of work is done, however, it makes little difference, but for general turning, the speeds should vary. Another difficulty experienced by beginners is in holding the tool still—rigidly so. They allow it to “bob” back and forth against the work, if it runs untrue, so that it is impossible to make a job. The tool must be held hard down, as if it grew to the rest, and never moved, nor receded, until the cut begun is finished. The “rest” should be of soft, wrought iron, since that material holds a tool with more tenacity; imposing less strain on the arms of the operator. It should be dressed off smooth as often as it gets badly worn, or cut by indentations. Cast iron is not good, and steel is not so good as wrought iron. A special rest should be kept for chasing threads with, since the least obstacle is enough, when running up a fine thread, to divert the chaser and spoil the job, by making a drunken thread. If we now suppose the lathe to be in good order, the centers true and well-turned to a gauge, the rod (if that is the job) between them and properly “dogged,” the centers oiled, and the rest at the right height, we shall be all ready to start. The rest should be high enough to bring the point of the tool a little above the center. Fig. 3. To rough off the outside, and make it run true, is the first step, and the tool must, therefore, be held as in Fig. 3, or so that the point and part of the edge alone engage with the work. This will take off a thin, spiral cut, without springing the shaft or making it untrue. The whole surface of the shaft must be thus run over, beginning at the right hand and shifting the tool as fast as one part is turned. The tool should not be moved rigidly in a straight line toward the belt, but by holding it hard down on the rest, so that the bottom edge bears as in Fig. 2, and rocking the tool on that angle, so that the point describes a curve, as in Fig. 4, the work will be turned evenly and true. Fig. 4. We must remark, in passing, that the person who reads these directions, and then undertakes to turn by them, will find that reading how to do a thing, and doing it, are two different matters. It looks very nice to see a skater darting over the ice at his ease, but try it once, and, if you never knew before, you will understand what experience means. Trying to teach a person to be a turner, in a book, is analogous. One can only indicate the general method, and leave experience to do the rest. Fig. 5. After the whole surface has been run over, the same tool may be used on the flat side for reducing the work to one diameter throughout the length. The reader must not assume that there is no other tool than a diamond point; he will find many others adverted to, as we proceed. Fig. 6. 23 24 25 26 It is most important that the ends of a rod or shaft should be squared up first, before the body is turned, for the removal of some slight inequality subsequently may cause the whole shaft to run out of truth. The center must be drilled with a small drill, and slightly countersunk. When the end is squared up, the center must be run back a little, so that the tool point may project over the drilled hole, and thus make it all true about the center, as in Fig. 5. This will make the work push over to one side of the center, but that is of no consequence. Let it run as it will; so long as it does not come out of the centers there need be no apprehension. Fig. 6, is another kind of roughing tool, to do heavier work with. Fig. 7. There are two kinds of tools used in foot lathes, called straight and heel tools. Fig. 7 is a heel tool. It is so called from the heel which is forged on the lower end. One form of the straight tool has already been shown. The heel tool is used on heavy work, and the object of it is apparent, namely, to hold on the rest, and so impose but little labor on the workman to retain it in place, or prevent it from receding. It is generally forged from half inch or five eighth steel. The steel is held in a handle twenty inches long, grooved on top to fit the steel, and furnished with a handle at right angles. This handle has a square eye in the top that the tool passes through. A nut at the end of it screws up the eye and binds the tool fast in the groove, so that it cannot slip. It is given complete in Fig. 7. The lower handle enables the workman to have great power over the edge, and to direct it from or to the work without danger of catching. The tool is used by resting the end on the shoulder, as in Fig. 8, and turning the lowest handle. Since the heel holds the tool from slipping, there is no occasion to bear against it. In fact, there is no occasion, at any time, to force the tool from the workman, but it must be turned sideways, back and forth. A piece, properly centered, may be cut in any way without destroying its truth. Fig. 8. 27 28 29 30 Fig. 9. Fig. 10. CHAPTER III. SCRAPERS, ETC. To suit different kinds of work, as previously stated, various tools are needed, but the reader must not expect to see them all illustrated in this book. The workman will learn what tools he needs, and make them for himself, which will be of more advantage to him than engravings could be. The tools here shown, will be found very useful in different places. Fig. 9 is the end of a thin-edged, flat scraper, and is chiefly to be used on brass work. It may be of any length and size, but for small lathes, and light work, it is cheaper and handier to make it of thin sheet steel, one eighth or one tenth of an inch thick, and to form the reverse end into a round nose, or half-circle scraper. It often happens that fillets or hollows occur, as in finishing ornamental brass work, in connection with flat surfaces. By having such a tool as this, the necessity of laying one tool down and picking up another, is obviated, for the two are combined in one. For iron work, it is customary to use a heavier and thicker tool for finishing. As in Fig. 10, the front edge is slightly raised or concave, to make it sharp and hold a cut well. All turning tools for finishing iron are made thicker than those for brass, and should have lips, or curved cutting edges. Such tools cannot be used for brass, as they are too sharp; the edges jump into the metal and spoil the work. A tool for scraping brass work of some kinds is made as shown in Figs. 11 and 12. Fig. 11. Fig. 12. There is no occasion to make the ends at different angles, except the convenience, before stated, of having four cutting edges on one piece, for any angle can be easily given by the position of the hand or the direction of the rest. These tools, here alluded to, are only to be used when the job has been all turned true and the scale removed; they scrape, merely, they do not cut. Such tools sometimes save a few steps at a critical period; that is, when the tool is well set and in place, so that the work is done better and more expeditiously. Apart from this consideration, there is the chance of cutting or injuring the hands, by the proximity of sharp edges. Under the control of an expert, however, there is little danger from this cause, as inspection will show. Skilful men that have worked a lifetime at their trade, have few marks or scars on their hands, as a general thing. When these scrapers are used on cast iron, or, indeed, on brass of a peculiar composition, they sometimes “chatter,” as it is called, and leave the work full of deep, unsightly marks, like those on the edge of coins. The cause of chattering is the rapid vibration of the tool, so that it springs away from, and against the work, with great rapidity, leaving traces of its edge on the work. Chattering may be prevented, by putting a piece of sole leather on the rest, between it and the tool. The tools with long handles are chiefly intended for heavy work, or that which requires both hands to the cut, but there are smaller tools than these, used by amateurs, wherein the common file handle, or one like it, only a little longer, is employed instead. 31 32 33 CHASING AND SCREW CUTTING. In an engine, or power lathe, all screws are cut by trains of gears, as mechanics well know, but in the hand lathe, which was the first machine, screws, both male and female, must be made by chasers or hubs, both inside and outside. The chaser itself must be made first, however, and that is done by a simple tool called “a hub.” Fig. 13. Fig. 14. Fig. 15. The chaser is first forged in blank, for an outside chaser, as in Fig. 14, and as in Fig. 15 for an inside tool. It is then filed up, and held against a hub, shown in Fig. 13, running in the lathe. This rapidly cuts away the chaser blank, and forms the teeth in it perfectly. The lines across it are spiral grooves, cut completely round from one side to the other, so that the hub cuts the blank like any other tool. Fig. 16 represents the chaser. Fig. 16. 34 35 CHAPTER IV. CHASERS, ETC. It is not always an easy task to chase a true thread on a piece of work, and even “the boldest holds his breath for a time,” if he has a nice piece of work all done but the thread, and that in a critical part. It is so easy to make a drunken thread, or one in which the spirals are not true, but diverge or waver in their path around the shaft, that many are made. That they are more common than true threads, is well known to mechanics. To start a thread true is quite easy with an inside chaser; for, strange as it may seem, it is seldom that a drunken thread is made on inside work; only have the bore itself true, and the chaser will run in properly. The case is different when a bolt or shaft is to be cut. With fine threads, the slightest obstruction on the rest will cause the chaser to catch and stop slightly. No matter how slight the stoppage, it is certain to damage the thread. The injury is more perceptible on fine threads than on coarse, for, in the former, if the threads do not fit (as they will not if they are drunken, one crossing the other, when both parts are put together), the drunken thread will not come fair with the other. In coarse threads, however, it will not be so apparent, for, by making the drunken thread smaller, it will have play and accommodate itself to its place. This is not workmanship, it is “make-shift.” To chase a true thread the rest must be smooth and free from burrs or depressions. Nice workmen keep a special rest, with a hard, polished steel edge, expressly for this purpose. If the chasers themselves are smoothly finished at the bottom, on an emery wheel, they are all the better. With these precautions, and others noted below, success is certain. When a thread is to be started, take a fine diamond-pointed tool, and hold it on the end of the shaft to be chased. Set the lathe going, and give the tool a quick twist with the wrist, so that a spiral will be traced on the work, like Fig. 17. Fig. 17. Some part of this will correspond with the pitch of the thread to be cut, and there is less liability of making it drunken. By a little practice, one is able to hit the pitch of the chaser exactly in making a start. “There is no trouble, after you once know how.” We have chased quantities of small screws, with forty-eight threads to the inch, and not a sixteenth of one inch in diameter. If the chaser once hesitates on such screws, they are spoiled. For heavy threads—seven and eight to the inch, which is about as hard work as any one wants to do,—it is the custom of some turners to use a tool with only two teeth, and some use only a sharp-edged cutter, like Fig. 18, to deepen the thread, the chaser being used afterward, to rectify the job. There is danger with this tool, unless it is used by an expert, of digging out the thread, so that the last end of it will be worse than the first. Fig. 18. Another tool, used in chasing heavy threads, is a doctor. This consists in having a fac-simile of the thread to be cut on the back of the chaser, and in applying a short set screw behind, so that, as the iron is cut away, the chaser may be followed up behind. Fig. 19 is the doctor, but the follower opposite the chaser is too narrow, and should be made nearly half a circle to avoid slipping; with this exception it is all right. These tools, and the screws made by them, are all inferior to those made by lathes with traversing mandrels; that is, a mandrel which slides in and out of the head stock, as in a Holtzapffel lathe. Fig. 19. This lathe has a series of hubs, unlike the one shown previously, slipped over the back end of the lathe spindle (furthest from the workman) and a fixed nut on the head-stock, which, being put in communication with the hub on the mandrel, drives the same in and out, according to the direction the cone-pulleys are turned. Of course, with such an attachment as this, there is no danger of making drunken threads, for the hubs which start the threads, are cut with a train of gears in an engine lathe, so that it is impossible for them to be incorrect. Moreover, a square thread, or a V-shaped thread, can be made with them, which is not the case with common chasers. In lathes that have traversing mandrels to cut screws, the tool itself remains stationary, but as this is obviously a disadvantage in many kinds of work, it is far better to have the tool advance and the mandrel revolve as usual. By this plan much time is saved, a greater range of work is possible with the same gear, and a piece that is chucked, or one that is between the centers, can be cut with equal facility. Any common lathe can be rigged to do this by putting a shell on the back end of the mandrel, between the pulley and the set screw, and slipping the hub over the shell, with a feather, to keep it from turning. To take a thread from this hub, a round bar must be set parallel with the shears, in easy-working guides. The bar must have an arm at one end, to reach over 36 37 38 39 40