Class T*^ ^■lo Book _5_2> The Scientific Steel Worker A Practical Manual for Steel Workers and Blacksmiths. The Art of Working Steel Thoroughly Explained. Also Steel Working Receipts and Mechan- ical Tables for Mak- ing Rings of all Sizes o f Iron, Steel a i-. d Angle Iron. BY OZRO A. WESTOVER Copyrighted December, 1903 by OZRO A. WESTOVER .t CONGRESS Tw* Cepies Received FEB 19 1904 CLASS C^ XXc. No, ' 'copy'V THE EDWARDS COMPANY, PRINTERS- MH Index. PAGE Judging Steel 9 Forging Steel 15 Forging Self-Hardening Steel 33 Forging and Tempering Steel Springs 35 Welding Steel 3g Annealing Steel 45 Hardening and Tempering Steel 52 Case Hardening 71 Thermite Welding 7g Miscellaneous Steel Working Methods 79 Brazing gg Tables of Diameter and Circumference of Circles. 86 Tables for Working Angle Iron 103 Tables of Weights of Round, Square and Octa- gon Steel per foot 105 Tables of Weights of Flat Steel per foot 107 Conclusion H2 Preface. In presenting this little book to the public the ob- ject is to give my readers practical instructions in the art of working steel according to scientific prin- ciples, and to do so in plain language and in the fewest possible words. I will not attempt to make a flowery display of literary talent, nor to amuse the readers with anything funny. The working of steel' in all its many branches is a trade, or rather a profes- sion, that in the past has not received much atten- tion. The time is now at hand when steel workers must study the scientific principles of working steel 1 or they will not be up to date. To be a good steel worker requires expert judgment and skill as well as patience. I learned my trade under a first-class steel worker in a blacksmith and machine shop, and have always made a specialty of steel work ; have im- proved every opportunity to learn more about steel ;- have worked in thirty-six different shops and thus- have had an extensive experience in steel working of all kinds, and have always been successful. In this work I recommend only what I know to be of value to steel workers. I am a member of Youngs- town Union No. 83, I. B. of B. To my brothers and all those who wish to improve themselves as steeL workers I dedicate his book. The Scientific Steel Worker. Judging Steel. All steel workers should, be able to judge steel as to quality and the amount of carbon it contains. It is just as essential that a steel worker should be a judge of steel as it is that a wood worker should be a judge of wood. One grade of steel is not fit for all purposes any more than one kind of wood is suitable for all pur- poses. The more carbon steel contains the harder it is. Ordinary tool steel contains from fifty to one hundred and fifty points of carbon. One point is equal to one hundredth of one per cent ; one hundred points is equal to one per cent. High carbon steel will harden at a lower heat than low carbon steel; is harder to forge and is more diffi- cult to weld. High carbon steel will not stand as much heat as low carbon steel. When working very high carbon steel be careful not to overheat it. High carbon steel will give far the best results for machine tools, such as lathe, planer and shaper tools; also drills, milling cutters, scribers, etc. Low car- bon steel will give the best results for all battering tools such as hammers, sledges, cold chisels, swages, flatters, fullers, etc., and all tools which must resist shocks or blows. 10 THE SCIENTIFIC STEEL WORKER. If tools are made of good steel of the proper car- bon content for the purpose, they will give far better results than they would if made of steel which is too high or too low in carbon. It is a great benefit to a steel worker to be able to determine the carbon con- tent of steel. LIST OF CARBON TEMPERS FOR SPECIFIC USES. Steel of from 50 to 60 points, hot work and batter- ing tools. Steel of from 60 to 70 points, battering tools and tools with a blunt point Steel of from 70 to 80 points, cold chisels, flatters,, hammers, sledges, set hammers and shear knives. Steel of from 80 to 90 points, stone tools, reamers > cold chisels and shear knives. Steel of from 90 to 100 points, drills, taps, dies, reamers, wood working tools and cutlery of all kinds. Steel of from 100 to 110 points, drills, taps, dies> machine tools, surgical instruments, etc. Steel of from 110 to 150 points, machine tools, en- graving tools, scribers, scrapers, very small drills and similar purposes. To correctly judge steel as to its carbon content requires practice and close observation. To begin with take a piece of octagon cold chisel steel, cut it on three sides and break it in two ; do not cut it all around, for if you do you cannot see how the fracture looks at the edges, which is an im- portant point when judging steel. THE SCIENTIFIC STEEL WORKER. H The carbon content of ordinary cold chisel steel is about eighty points. Examine the fracture carefully with a good pocket magnifying glass and you will notice how the grain of the steel looks. You will also notice all around the outside there is a thin de- carbonized skin about one-hundredth of an inch thick - the thicker this skin is the lower the carbon content; this is for steel as it comes from the mill " unan- nealed." Examine the fracture carefully all over and re- member how it looks. The fracture will be rough or uneven; the small points which appear all over the fractured surface will be rounding, providing it is good steel. Inferior steel will show sharp points on a fractured surface, and several minute sparkling particles can be seen with the naked eye. Low car- bon steel when broken looks coarse-grained and rough on the surface; the lower the carbon content the rougher the fractured surface will be. High car- bon steel will break easier than low carbon steel- the fracture will be nearly smooth and the grain be' fine and present a compact appearance; the higher the carbon content the smoother the fracture. The fracture alone is not an altogether accurate index to the carbon content of steel, as the appear- ance of the fractured surface can be greatly modified by the manner of heating and hammering and by the temperature at which the bar is finished. A bar of steel can be worked in such a manner that several 12 THE SCIENTIFIC STEEL WORKER. pieces can be broken from it, each exhibiting a dif- ferent fracture. The decarbonized skin, however, will be the same no matter how the steel was hammered or rolled, and regardless of the heat the bar was finished at, but will be very much thicker after the steel is annealed ; the grain will also be much coarser after annealing. After you examine the fracture of eighty carbon steel get a piece of steel which is known to contain one hundred points and carefully examine it. Then get another piece that is known to contain one hun- dred and twenty points. You will notice a great dif- ference in the fracture and in the thickness of the decarbonized skin. Another guide for estimating the carbon content is in forging. Notice the scales which fall from low carbon steel. They will be thick and rough ; the lower the carbon the thicker and rougher the scales will be, and vice versa. The scales from high car- bon steel will be thin and smooth. The higher the carbon the thinner and smoother the scale. Another guide for estimating the carbon content is the way tools look after being used several days. A cold chisel or any tool which receives blows, if made of steel containing from seventy to eighty points carbon, the head of the tool will batter up and spread out and finally curl over and turn back against the tool without breaking. If such tools are made of steel containing from ninety to one hundred points carbon, the heads will THE SCIENTIFIC STEEL WORKER. 13 not batter easily and will chip off all around as soon as the head commences to spread. If the tool is a natter, or any such which receives heavy blows it will split off in large pieces and sometimes will split in the center clear to the eye. The higher the carbon the less the heads will spread and the more they will chip off. If battering tools are made of steel containing much less than seventy points carbon, the heads will batter up very easily and spread out entirely too much unless the head of the tool has been hardened. Watch all these different points carefully and examine every fracture you see. Steel which contains forty points of carbon or less will not harden in a satisfactory manner and will not hold an edge. If you follow these directions you will be able to determine the carbon content of steel with sufficient accuracy for all practical purposes. In a shop where I was working a few years ago they had some machinery steel which contained a large amount of carbon. We made some small forgings of it. I noticed it worked rather hard and was difficult to weld. The machinists complained about the forgings being so hard that they could not machine them. The Superintendent wanted to know what caused those forgings to be so hard. I told him it was high carbon steel and that the only way to soften it was to anneal it after forging. The Su- perintendent said he knew it was not high carbon 14 THE SCIENTIFIC STEEL, WORKER. steel. I told him that I positively knew it was. So to settle the matter he sent some of the steel to a chemist for analysis and told me "that a chemist was the only man that could tell any thing about the carbon content of steel." I told him "that the steel contained between sixty and sixty-five points of carbon," and asked him to let me know how much carbon the chemist found it to contain. He said, "All right; but you would not know anything about it if I do tell you." The chemist reported the steel to contain sixty-three points of carbon. The Super- intendent showed me the report and asked me how I could tell how much carbon steel contains. I told him, " You would not know anything about if I did tell you. A chemist is the only man that can tell anything about the carbon content of steel." He did not ask me any more questions just then. A few days later he brought me a piece of steel and asked me how much carbon it contained. I ex- amined it by all the before-mentioned methods of judging steel, and told him it contained about one hundred points of carbon. He had it analyzed and found it contained ninety-eight points of carbon. He was then thoroughly convinced that I knew some- thing about steel, and that a chemist is not the only man that can determine the carbon content of steel. I do not claim to be as accurate in all cases as I was in the above mentioned tests, but will say I can THE SCIENTIFIC STEEL WORKER. 15 determine the carbon content of steel sufficiently ac- curate for all practical purposes. Forging Tool Steel. Forging tool steel is a subject which has received less attention than annealing or hardening. Nearly every smith has had more or less experience in this line, but the ones that forge tool steel as it should be done are very scarce. Most of them think all that is necessary is to forge the article to proper shape and size. They pay very little attention to the heat so long as the steel does not fly to pieces. It is all right in some smiths' estimation but not with the experi- enced steel worker. That sort of heats will do for iron but is the ruination of tool steel. Occasionally we find a smith that forges steel at too low a heat which is nearly as bad as overheating. Tools that are forged at too low a heat will never give satisfaction. Forging at too low a heat will cause the steel to be very brittle, and is sure to cause internal strains which will cause the tool to be very liable to crack or spring in hardening. I have seen a great many smiths that overheated steel and also hammered it long after all traces of red heat had disappeared. Hammering steel at black heat should not be done under any circumstances. To secure the best results and properly forge tool steel, have a good clean fire deep enough to allow a good body of fuel under the steel- so that the blast will not strike it, and keep the steel slightly covered 16 THE SCIENTIFIC STEEL WORKER. with soft coke or charcoal. Heat slowly and evenly; turn the steel over often. The amount of heat which steel will stand, without injury, depends upon the na- ture of the steel. For a large tool or forging, that requires considerable work and several heats. Steel of low carbon may be heated to a very light red or dark yellow for the first few heats, but should be fin- ished at a dark red. Remember that when the red disappears it is time to stop hammering. When finishing a tool several heavy blows are necessary to make the steel compact and fine grained. We often see a smith who thinks he is a good steel worker who will hammer steel when it is black, and even put a set hammer or flatter on it and have the helper strike it with a heavy sledge ; or, still worse, pound it with a steam hammer. Hammering steel when at a black heat will ruin small and thin tools, and is a useless waste of time and energy on large pieces and will do more harm than good on all sized tools. We often see a smith heat a cold chisel nearly hot enough to weld and hammer it long after all traces of red is gone, then heat it about twice as hot as it should be, then harden it and draw the temper to a nice blue. No doubt he thinks that he dressed that chisel just as good as any one could, and when the chisel is brought back broken the smith will say: "The steel is no good, or the chisel was not ground right, or else the man that used the chisel did not understand his business." THE SCIENTIFIC STEEL WORKER. IT Good cold chisels, like good steel workers, are- scarce. Cold chisels are the most abused tools in the world. It requires knowledge and skill to make a first-class cold chisel. I have seen hundreds of smiths dress chisels, but among them all I found only- three who forged, hardened and tempered chisels as they should be done to obtain the best results. I have seen old tool smiths who had worked tool steel for fifty years and were good tool dressers on most tools. When they dressed cold chisels they would not heat too hot or hammer too cold, and would also- give the chisel the proper temper. But that is not all that is necessary to make a first-class chisel. There is more science in forging steel than there is in hardening and tempering. Some steel workers may not believe this but I can prove it. If a man is a scientific steel worker he can make a good chisel every time providing he has good steel to make it of. A smith w T ho has not got this knowledge may once in a while make a good chisel, but he does not know why that chisel is any better than the others ; and no doubt if he should make a dozen more from the- same bar of steel he could not get another as good as that one. I have seen this happen to lots of men who were supposed to be good steel workers. Cold chisels should be made of a good grade of steel con- taining from seventy to eighty points carbon. To make a cold chisel, first cut off enough steel to- make it the desired length. Heat it to a bright red back about three inches, then trim off the corners oik 18 THE SCIENTIFIC STEEL WORKER. two parallel sides so that the end will have a short, blunt point; this will keep the edges from lapping •over in forging. Draw the chisel on the horn of the anvil the first heat. This will draw it much faster and will not spread it out sideways as much as draw- ing on the face of the anvil. Consequently it will not require as much hammering on the edges to get it into the proper shape. The less you hammer a chisel on the edge the better it will be. When you have hammered the chisel on the sides until it is a dark red, never turn it up edgeways and strike it; but if it must be hammered on the edge put it back in the fire and heat it again ; then do all the ham- mering on the edge that you are going to do. Then hammer it evenly and thoroughly on the sides, but do not strike the edges again. When you get the chisel nearly to size and shape, medium heavy blows are necassary to close the pores and pack the steel. This should be done when the steel is a very dark red, but when the red disappears stop hammering immediate^. Put the chisel in the fire but do not turn on any blast. As soon as it is a dark red take it out and give it several good blows on each side, then heat again and hammer as before. Repeat the operation three or four times but remember to keep your hammer off the edges. If the chisel gets too wide or the edges get crooked you can file or grind it to shape. If you wish to make a flat chisel out of three- quarter inch steel draw it out so that it will be about THE SCIENTIFIC STEEL WORKER 19 one-eighth of an inch thick at the end, and about one-fourth of an inch thick three inches from the end. A chisel of this size should be about seven-eights or three-quarters of an inch wide and a trine thicker in the center than it is at the edges. When you have the chisel forged let it cool off then grind it. When the chisel is ready to harden heat it to an even dark red back as far as it has been drawn. Plunge it in the bath straight down as far as you have it hot enough to harden ; move it up and down a little, but not sideways. As soon as the -chisel is cooled through take it out and rub one side bright (of course we have only enough heat left in this chisel to start the temper a little; that is all we want) ; now hold it over the fire and draw it evenly all over alike to a regular cold chisel blue. A chisel made in this way can be worn back three inches before it needs dressing and the edge will stand far better than the ordinary chisel. One chisel made in this way will last longer than three dozen chisels made like a blunt wedge and hardened about one-fourth of an inch on the end as it is gen- erally done. This way of forging steel holds good on all flat tools and tools that can be finished on the flat sides, such as side tools, flat drills, cut-off tools, scrapers, mill picks, stone tools, etc. Always use a heavy hammer for finishing a tool, or else use a good set hammer or flatter. Remember to finish on the flat sides and keep off the edge and finish at a dark 20 THE SCIENTIFIC STEEL WORKER. red and never strike steel after all traces of red have gone, and never overheat it. The above is the scientific method of forging tool steel and is the secret of my success as a steel forger. I have made and dressed a great many tools with un- rivaled success. To show the superiority of my woikmanship: I made two cold chisels of seven-eighth octagon steel and drove one of them clear through a cold bar of one and three-eighth inch square steel, and the other through a cold bar of two and one-quarter inch square iron. These chisels ^ere only one-eighth of an itch thick at the point, and were drawn tapering nearly four inches; the entire length is about seven and one-half inches; width at point seven-eighths of an inch. These chisels were forged according to the directions given in this work. I hardened and tem- pered these chisels the entire length to keep them from bending, with the exception that they are ex- actly the same as I always make flat chisels. They were driven through the bars of steel and iron with a steam hammer in the blacksmith shop of the Youngs- town Iron Sheet and Tube Company on the 16th day of November, 1903, in the presence of the foreman blacksmith, David Howells, and all his blacksmiths and helpers. These chisels were never taken out of the steel and iron. I still have them. The edges were not damaged in the operation. The points pro- ject through about three-quarters of an inch. If you doubt this, write Mr. Howells. THE SCIENTIFIC STEEL WORKER. 21 Nearly three years ago I dressed a flat cold chisel for George R. Hasbrouck, No. 638 West Main street, Ravenna, Ohio, a machinist employed by the John F. Buyers Machine Company. He has used that chisel almost three years, and during that time it has not been in the fire. Over two inches has been worn off the cutting end and about the same amount pounded off the other end. This chisel was drawn out long and thin. Was not over one-fourth of an inch thick four inches back from the end, and was hardened and tempered back about five inches; was seven-eighths of an inch wide, nine inches long and less than one-eighth of an inch thick at the point, and not over three-sixteenths of an inch thick three and one-half inches from the point. This chisel is still in use and will last for several months more. It has been used on all kinds of iron and steel that a man ever cuts with a cold chisel. Mr. Hasbrouck is a first-class machinist and knows how to grind and use a chisel, which are two things that a great many machinists do not know. If any of my readers doubt what I say about this chisel they will please write to Mr. Hasbrouck and see what he has to say about it. Nearly every blacksmith and toolsmith imagines that it ruins tool steel to upset it, but I know better. If the upsetting is properly done it will do no harm. To prove this, I have often upset steel for broad nosed tools and they always gave satisfaction. If you wish to upset steel, heat it to a bright red and 22 THE SCIENTIFIC STEEL WORKER. upset it some larger than the finished size so that the steel can be thoroughly packed by hammering it on two parallel sides when the steel is at a dark red : but after you have commenced to pack the steel do- not strike on the edges. If you hammer steel on all sides when it is at a dark red it will cause strains and leave the steel in a far worse condition than it was before it was forged. I do not claim that upset- ting steel is any benefit to it, but if properly done it will not harm it. Several years ago I went to a large shop and got a job on the tool fire. The first thing they gave me to do was to dress some cold chisels. The first one I got hold of had been drawn too thin on the end. I got it red hot, and as there was nothing in sight with which to cut it off, I thought I would upset it a little and had struck it about four or five blows on the end when the foreman came to me and said : '• See here, young man, that will never do. Don't you know that it ruins tool steel to upset it? Do yau claim to be a tool smith and do the like of that? I guess you never dressed many tools. You are too young a man to know much about working steel any how, and when I see a man upset steel that settles it. I know he don't know nothing about dressing tools. ' r And so he went on from bad to worse and gave me an awful calling down and did not give me a chance to get a word in edgeways. But while he was blowing off his surplus steam I dressed and tem- pered the chisel. THE SCIENTIFIC STEEL WORKER. 23" The foreman said: "That chisel is good for nothing." I knew he was mistaken, so said: "Look here; if I have spoiled this chisel I will pay for it; but be- fore it goes any farther let's try the chisel and see if it is ruined or not." "It's no use to fool away time trying that thing. It has been upset at the point and drawn entirely too- thin and too far back. It looks more like a wood chisel than anything else ; it might possibly cut lead but will not last two minutes on iron." I told him "we would see about that." I ground the chisel, then took another chisel and put it in a vice and with a four-pound hammer I drove the thin chisel into the solid tool steel one-half inch deep in four or five different places ; then took the chisel in a pair of tongs and held it on a large piece of cast iron which happened to be lying on the floor. I told the helper to hit the chisel with the sledge. He picked up a fourteen-pound sledge and went at it. By this time there was at least a dozen men standing around to see what the new toolsmith was up to. The helper struck the chisel forty or more blows and made the big chips fly clear across the shop. I then held the chisel on the horn of the anvil so that the edge projected over about two inches and struck it ten or twelve good blows sideways on the end with a two pound hammer, but the chisel did not bend or break and the edge was not damaged. 24 THE SCIENTIFIC STEEL WORKER. They were a surprised crowd. They had nothing to say, but I had. Perhaps I said too much. I told the boss that "I knew exactly what I was doing when I was working steel, and would bet him or any man in the shop fifty dollars against ten that the chisel I had dressed would do more work without be- ing dressed again than any ten chisels that any man in the shop could make," but none of them took me up. About this time the Superintendent of the ma- chine shop came in and stopped to see what was going on. I said: "Look here, gentlemen," taking one hundred dollars from my pocket, "I will give you a still better chance. You can have sixteen chisels to my one and I will bet you one hundred dollars to twenty-five that this one chisel will do more work than your sixteen chisels will." The Superintendent said to the foreman black- smith : "Sixteen chisels to one, and one hundred dollars to twenty-five ! That is a good bet even if you lose; take him up." The foreman did not feel sporty just then. He -aid: "Take him up yourself if you want to; I am not betting on another man's game." I said : "It will be money in your pocket not to ; but if I were foreman of a large shop like this and had shot off my mouth like you have, I should -awfully hate to be bluffed as you have been." That was too much for the old chap. He got angry and told me " to get out of there, the sooner the better." THE SCIENTIFIC STEEL WORKER. 25 Well, I took his advise and got out and never went back. If I had kept my mouth shut I might have stayed there and had a good job, but guess there was nothing lost, for I soon got another job in a shop near by at easier work and better wages. I saw the old foreman several times after that, but he never saw me ; that did not hurt my feelings any. Since then I have often offered to put up from twenty-five to one hundred dollars to back my word and tools, but have never found a man who would put up the cash. I have found it to be an excellent way to shut men up when they get too fresh. I never make any statements that I cannot prove, and never allow any one to bluff me. Forging Hammers, A good hand-made hammer is something that every blacksmith and machinist is proud of. Ham- mers should be made of a good grade of steel con- taining about eighty points carbon. To forge a hammer, heat the steel evenly to a bright red or dark yellow heat and punch the eye first ; then fuller it all around on both sides of the eye. Use a small fuller first and leave stock enough in the middle to allow for working the eye to proper size. The eye should be punched with a small punch made expressly for that purpose ; it should be tapering and about twice as w de as it is thick; the edges should be rounding. The punch should be about three-eighths wide by one-fourth of an inch thick at the small end, and 26 THE SCIENTIFIC STEEL, WORKER. about one inch wide by one-half inch thick at the large end, and about five inches long. The next thing to be done is to spread the eye. This should be done at a bright, red heat with a fuller and set ham- mer. After spreading the steel at the eye, fuller it a little all around again ; draw the ends down to the desired size, then fuller it again with a larger fuller. The eye should be worked on both sides, and the tapering drift or punch should be driven in from each side so as to finish the eye larger at each end than it is in the middle. If the eye should be made the same size all the way through, the hammer wiJl not stay on the handle nearly as well as it will if the eye is smaller in the middle. When you have the hammer finished to size and shape, heat it to an even, bright red; stand it on end and strike it on top; one good blow will be sufficient; do not strike it hard enough to knock it out of shape. The fullering and punching the eye causes strains in the steel; the blow on the end will relieve the strains. After this is done the hammer should be thoroughly an- nealed. You have all seen hammers that were cracked or broken at the eye, or one end broken off. The rea- son of this[is, the man who made the hammer did not remove the strains. After the hammer is annealed it should be finished up by turning and filing, then hardened and tempered to a dark straw color. A hammer should be tempered so that a good, fine file will cut it a little. It is better to have a hammer a THE SCIENTIFIC STEEL WORKER. 27 little too soft than too hard. Never temper a hammer hard enough to mark the anvil, for hammers are easier to dress than anvils. Sledges should be hardened and tempered the same as hammers. Flatters, fullers and all anvil tools should be struck on the end to relieve strains caused by forging, then thoroughly annealed. Never fuller a flatter or swage below the eye, and do not draw the heads of battering tools too small. If these directions are followed you will not be troubled with tools breaking. I have found it to be a good idea to harden the heads of battering tools. To do this, heat the head to a dark red and harden ; then draw the temper to a very pale blue. When I was working for the Morgan Engii eering Company, of Alliance, O., one day the man on the next fire to me made a nice flatter. He worktd < n it about three hours, fullered it in on the corners below the eye and sn oothed it up all over in fine style. He then hardened it and drew the temper, then polished it up all over. When finished he showed it to me and said it was tl e best flatter in the shop; but he did not use it more than an hour until it broke square in two where it had been fullered. He was so badly beaten he could not say anything for a while, but finally said "that the steel is good for nothing." That is just what I expected to hear him say. 1 have often heard other smiths say the same thing when their tools broke. I needed a new flatter 28 THE SCIENTIFIC STEEL WORKER. just then so made one from the same bar of steel. I used it very hard, but it never broke. He wanted to know why his natter broke and mine stood so well, when I told him the reason. He said: "That would not make any difference ; you must have tempered your natter in oil, or something else to toughen the steel ; it is poor stuff, anyhow, and your natter will break in two just like mine did, some of these times." But he was badly mistaken. Some smiths are always having trouble with their hot and cold cutters which either break or bend; some will crack in hardening. The*e difficulties can be overcome by following the directions given for making cold chisel?. A cold cutter should be made of a good grade of steel containing about seventy-five points of carbon. Leave them heavy enough to stand the work they are intended to do. Cold cutters should be forged and hardened the same as hand cold chisels, but should be tempered a trifle softer. If you follow these di- rections you will be able to make a cold cutter which will cut off at least a thousand pieces of seven- eighths inch octagon tool steel without being dressed ; or cut from thirty to fifty large steel rails in two without being dressed. I have seen over a dozen chisels go to pieces on cutting one steel rail in two, but they were none of my make. Remember, the secret of making good chisels lies in the hammering and h' ating, but not in the hardening bath. Chisels and cutters of all kinds can be successfully hardened THE SCIENTIFIC STEEL WORKER. 29 in clear water, salt water or any of the hardening solutions given in this book. Forging Twist Drills. This is something you do not see done every day. To make a one-half inch straight shank drill, take a piece of one-half inch round steel; flatten three or four inches of it; do not stretch the steel endways; just flatten it to about one-eighth of an inch thick; do not strike it on the edges only enough to keep it straight; let it spread just as wide as it will. Be sure to have it the same thickness back as far as it has been flattened. Then heat it a bright red; stand it up edgeways on the anvil; take a light hammer, begin at the back end of the flattened portion and strike it on the left hand corner, or, in other words, strike it on top; only reach over to the left enough to catch the corner. Ket p working toward the point with quick, light blows; when you get to the point turn the drill over and begin at the back end as be- fore. You will see you have knocked it a little in a twist all the way along, and have upset the edges the entire length. That is just what we want. Keep right on as long as it is red hot; then heat it again and hammer the same as before. It will look n ore like a twist drill every time you strike it. If you work fast you can forge a nice drill in about five or six heats; when done forging, carefully anneal it, then file out the flutes with a round file and finish 30 THE SCIENTIFIC STEEL, WORKER. the edges and sides with a fine flat file. Harden it the entire length of the twist and draw the temper to a straw color. Any skilful smith can, with a little practice, make a nice drill. An excellent reamer can be made in the same way, only forge the twist in it the opposite way (left hand). Make the reamer tapering instead of straight, and file the clearance in it the same way as a twist drill. This will make a right-hand reamer. I have made a great many twist drills, and have often been called a liar for saying I made them, be- cause the man I was talking to had never seen a good hand-made twist drill. Whenever a man tells me he does not believe I made the drill, I always offer to put up twenty -five dollars or more that I can make another one just as good in his presence. That al- ways settles the matter in short order. Forging a Butcher Knife. Steel for knife blades should contain about one hundred points of carbon. To make a butcher knife you should have a piece of seven-eighths by one-eighth inch steel. Cut off enough to make the knife the desired length ; heat it ti a dark red and bend it a little edgeways; then draw the inside edge. It will straighten in drawing. When drawing the edge, commence at one end and work to the other, then turn it over and work as be- fore. Be careful not to over-heat the steel, and ham- mer as much on one side as you do on the other; THE SCIENTIFIC STEEL WORKER. 31 do not hammer after the red has disappeared. Draw the knife as thin as you want it, and trim the point to the desired shape. If you hammer more on one side than the other, the knife will be liable to spring in hardening. When you are ready to harden the knife heat it edge down, in a clean fire, using very little, if any, blast; heat it evenly the entire length to a dark red. Only heat the blade hot enough to harden about one-half its width ; then plunge it in the bath edge down. Any bath may be used — oil of most any kind will do. By only hardening the front half of the blade you will leave the back tough and strong. Knives hardened in this way cannot be easily broken. If knife blades are hardened in water, draw the temper to a purple ; but if hardened in oil or grease draw the temper to a straw color. Woodworking tools should be made out of good steel containing about one hundred and ten points of carbon, and carefully forged according to directions given for forging cold chisels. This method holds good on all flat tools, no matter what they are in- tended to cut. Woodwork tools should be hardened and drawn to a straw color. Every shop needs a good steel worker, but lots of them have to get along with poor tools because they cannot get a man who understands working steel. This is why there is so much self-hardening steel used, simply because they could not get their tools dressed so they would do the work. If a tool is 32 THE SCIENTIFIC STEEL WORKER. properly forged, hardened and tempered it will cut harder material than any self -hardening steel. Self-hardening steel is not a success for turning chilled rolls. A tool made of a good grade of steel and properly hardened is far better. For roughing sanded castings, and for work that runs at a high speed, the self-hardening steel is the best, but not for a finishing tool. Making 31 a chine Tools of Common Iron. A lathe or planer can be made of common iron which will cut the hardest kind of material. To do this, forge the iron tool and grind it ; then take a piece of thin cast iron; heat the tool almost to a welding heat; also heat the cast iron to a melting heat. Rub the melting cast iron over the end of the tool ; it will unite to the wrought iron ; get enough of the cast iron onto the tool to form a heavy plate on the cutting edge and plunge it into cold salt water; draw no temper. This will make a tool that will cut glass or anything else except a diamond. You cannot make a mark on it with the best file in the world. I have made tools in this way which cut chilled castings that self-hardening tools would not begin to out. Tools made in this way will not wear very long because the cast iron plate is thin. It is the cast iron that does the cutting. Remember that all tool steel forgings should be annealed and all tools should be annealed or heated red hot and allowed to THE SCIENTIFIC STEEL WORKER. 33 cool in the air. It is very important to have an even heat for forging, hardening and annealing. An- other very important point in forging is to have an anvil which has a good, smooth face. Never use a hammer or sledge which has a rough face or sharp corners, and avoid hammering on the edge of tools whenever possible. Forging Self -Hardening Steel. To do this, heat the steel slowly and evenly ; give it plenty of time to become heated clear through; do not overheat it or hammer at too low a heat. Self- hardening steel will stand a higher heat than most smiths think it will, providing it is heated evenly and slowly. When you have the tool forged to shape, heat the cutting end to a bright red and lay it out to cool; let the hot end project over what you lay it on so that the air will circulate freely around it. If tools treated in this way are not hard enough, cool them in a cold air blast, but never put self-hardening steel in water. " Novo Steel" must be forged at a very light, yellow heat, then heated to white welding heat and hardened in an air blast. It is almost im- possible to burn Novo steel. " Zenith Steel " should be forged at a white heat ; should not be hammered only at a very high heat; it cannot be overheated. Zenith steel should be hardened by heating to a drip- ping, white, welding heat and thrust the point into a block of cold lead, or boiling water, or cold air blast. " Bex SteeV must be forged at a bright red or dark 34 THE SCIENTIFIC STEEL WORKER. yellow heat and allowed to cool in the air; then re- heat the portion desired hard to a white, welding heat and harden it in an air blast. For all the new steels follow the directions sent with the steel and you will have no trouble. The new air-hardening steels are easily forged and far su- perior to the old-fashioned self-hardening steels in eve r y way. These new air-hardening steels will not give satisfaction unless the above directions are closely followed. They must be forged at a high heat and hardened at a much higher heat. Such treatment would ruin ordinary carbon steel. When working carbon steel remember that the proper forging heat is too hot for hardening or annealing, and the hardening heat is not hot enough for forg- ing. To obtain the best results with ordinary tool steel, forge the tool, then anneal it or heat it to an even dark red and allow it to cool in the air; then heat again to a dark red and harden. For dressing all kinds of tools follow directions given for forging. Dressing Anvils. This is a job which most smiths are afraid of, but is not as great an undertaking as some imagine it to be. If the anvil is not too large it can be easily handled by two short bars properly fitted into the holes in the anvil made for that purpose. The easiest and best way to dress an anvil is to anneal it and have the face planed, then harden it properly and the anvil will be as good as new. If you cannot THE SCIENTIFIC STEEL WORKER. 35 get the face planed it can be dressed hot, then when cold it should be filed or ground smooth before hardening. Build a large, deep fire; heat the anvil nearly all over ; if you heat only the face it will be very liable to loosen the steel face and ruin the anvil. When you get it to an even, bright red take it out and upset the edges, then smooth it up all over the face with a large natter. When heating be careful not to overheat the corners. For hardening follow directions given for hardening anvils in Hardening and Tempering. Forging, Hardening and Tempering Springs. Making springs is a job that the majority of smiths are not very familiar with, and a job that re- quires care and skill. For all small forged springs use tool steel of about eighty or ninety points carbon. Small springs should be forged heavy enough to al- low the springs to be filed smooth before hardening. When forging springs be very careful not to over- heat the steel, and do not hammer it after the red has disappeared; and do not hammer on the edge any more than is actually necessary. When you heat a spring to harden be very carefel to get an even heat, but do not heat it any hotter than is necessary to produce the desired results. Do not attempt to heat a very small or thin spring in an open fire. If you have nothing but an ordinary forge with which to heat the spring, take a piece of pipe of suitable size and plug up one en I air 36 THE SCIENTIFIC STEEL WORKER. tight; place it in the fire and cover it over with coke ; leave the open end project out a few inches, then heat the spring inside of the pipe. The above method of heating is not as good as a furnace, but is a great improvement over heating in an open fire. Very thin springs harden nicely by heating red hot and plunging into a cake of common yellow soap; if too stiff, draw the temper a little. All kinds of springs harden nicely in oil; melted tallow gives good results. After a spring is hardened in oil or grease it is necessary to draw the temper. To do this, hold the spring over the fire until the oil burns off; then try the spring; if it is too stiff, dip it into the oil again, taking it out instantly and proceed as before. For some grades of steel it may be neces- sary to burn the oil off three or four times to obtain the desired elasticity. Some kinds of springs give good results when hardened in boiling water and the temper drawn to a blue; this is all right with some kinds of steel but will not do for all kinds. Springs can be successfully hardened in salt water or any bath used for hardening tools. Heat the spring to a dark, cherry red and plunge it edgeways, straight down in the bath. 1 his will make the spring very hard. To temper springs, harden in this way: You should have a box or barrel, partly covered, so as to make it as dark inside as possible. Then heat the spring slowly and evenly until you can see the first THE SCIENTIFIC STEEL WORKER. 37 trace of dark red when the spring is held in the dark; then allow it to cool in the air. If properly done this makes an excellent spring. I believe it to be the best method of hardening and tempering trap springs. Another very good way to harden and temper trap springs, made of tool steel, is to heat them to a very dark red, and harden in water at about one hundred degrees F. If this makes the spring too stiff draw the temper by dipping the spring in oil and burning it off as described before. If you have several springs to temper, fasten them together and hang them in a kettle of melted tallow; place the kettle over the fire and boil for a few minutes, then remove the springs and allow them to cool in the air. Good springs cannot be expected if the steel is overheated in forging and hardening. All light springs should be made of tool steel; large springs should be made of spring steel, .springs made of spring steel should be hardened in oil or tallow and tempered by burning off the oil or tallow as described before. Spring steel contains considerable carbon and will not stand high heats. It will hirden at a very low red. When forging all kinds of springs be very careful not to overheat the steel; hammer it thoroughly all over on both flat sides when the steel is a very dark red, but do not hammer after the red has disap- peared; and do not hammer on the edge after you have commenced to pack the steel. Round springs 38 THE SCIENTIFIC STEEL WORKER. should be hardened and tempered the same as flat ones. Small coiled springs that are made of drawn wire and coiled cold, will not require hardening or temper- ing. Nearly all small coiled springs are coiled cold and made of drawn steel, up to and including one- fourth inch wire. Occasionally larger sizes are coiled cold. Coiled springs which are coiled hot will require hardening and tempering, and should be done by heating the springs to a cherry red and plunging in cold oil ; then burn off the oil over the fire, or boil the springs in melted tallow as described before. Brass springs cannot be hardened by heating and cooling in a bath. Copper and brass is tempered by rolling or drawing cold, and annealed by heating red hot and cooling in water or brine. Welding Steel. This is a subject in which every blacksmith has had more or less experience. We all know that some grades of steel can be weldtd } nd others cannot. The more carbon steel contains the more difficult it is to weld. Steel which contains over one hundred and twenty points of carbon will not weld in a satisfac- tory manner; neither will the air hardening steels. To successfully weld steel it is necessary to have a good, clean fire as free fiom sulphur as possible. For welding on the anvil a short lap gives the best THE SCIENTIFIC STEEL WORKER. 39 results. If you are troubled with the steel slipping back, take a blunt chisel and cut a notch in both pieces close to the back end of the scarf ; when you take the pieces out to weld place the two chisel cuts together ; this will prevent slipping. If you wish to make a "V" or split weld, notch the pieces that go inside and hammer the laps down over it. For welding flat thin pieces of steel some smiths split both pieces. If you wish to do this, split both pieces before you scarf them. Then when you scaif the ends let the inside corners of the scarfs spread as much as they will ; then when you put them together the inside corners of the scarfed ends will reach onto the solid steel and will insure a good weld and leave the center strong and solid. The above is the best way of welding flat springs. After the weld is made, forge the steel to the desired shape, but leave it a little thicker than the finished size ; then finish it to the proper thickness with a flatter and sledge; give it several good blows on both flat sides while the steel is a dark red, but do not hammer on the edges after you have commenced to pack the steel. To weld tool or spring steel it is necessary to use a flux to keep the steel from burning. Borax is gen- erally used for this purpose. Borax always contains sulphur and sulphur is injurious to steel. If you have nothing but borax you can greatly improve it by melting it and boiling it dry. It will then be what is called charred borax and will be found to give far better results than borax in its natural state. 40 THE SCIENTIFIC STEEL WORKER. Any of the following welding compounds will give far better results than borax on all kinds of steel. The first is an excellent compound. I have used it several years and on all kinds of work with splen- did results. I paid three dollars for the recipe and have of i en sold it for from one to three dollars. WELDING COMPOUND NO. 1. Pulverized Borax lib. Carbonate of Iron 2 oz. Black Oxide of Manganese 3 oz. Mix thoroughly and use as borax, only heat the eteel a little hotter. WELDING COMPOUND NO. 2. Pulverized Borax 1 lb. Nitrate of Potash .1 oz. Carbonate of Iron . 2 oz. Use as borax. WELDING COMPOUND NO. 3. Clean sand. 5 lbs. Powdered Sulphate of Iron. 3 oz. Black Oxide of Manganese 3 oz. Table salt 4 oz. This compound gives splendid results on open hearth and Bessemer steel, but is not intended for tool steel. Use as borax. THE SCIENTIFIC STEEL WORKER. 41 WELDING COMPOUND NO 4. Borax 1 lb. Salt Peter 2 oz. Powdered Charcoal |oz. Use as borax. WELDING COMPOUND NO. 5. Borax 1 oz. Steel or wrought iron filings 1 oz. Rosin 1 oz. Sal- Ammoniac 2 oz. Carbonate of Iron 2 oz. Use as borax. WELDING COMPOUND NO. 6. Borax. ... 1 lb. Dry Venetian Red 4 oz. Black Oxide of Manganese 2 oz. Use as borax. WELDING COMPOUND NO. 7. Borax 1 lb. Fine wrought iron drillings ...... .1 lb. Clean welding sand 1 lb. Carbonate of iron 3 oz. Mix thoroughly. Use on both sides of the scarf. WELDING COMPOUND NO. 8. Pulverized glass 1 lb. Pulverized borax 1 lb. Use as borax. 4 42 THE SCIENTIFIC STEEL WORKER. WELDING COMPOUND NO. 9. Charred Borax 1 lb. Carbonate of Iron 3 oz. Use as borax. Compounds Nos. 1 and 5 are excellent for welding tool steel and restoring burned steel. To test, take an old file, heat the end until it flies to pieces, then, dip the end in the compound and let it remain four or five seconds; then with quick, light blows weld up the end, draw it out and make a cold chisel out of it. You will be surprised at the results. Overheated steel will never be as good as it was before being overheated. But accidents will happen to the best of us sometimes, and it is well to know how to make the best of them. All of these compounds are first-class and are not expensive, are easily made and far better than borax for all classes of work. We often see a smith take a dozen heats on a weld and then not get a solid job. Some are afraid to heat the steel hot enough, others heat it too hot. Some will plaster both pieces all over with borax and then try to stick them together with both scarfs swimming with melted borax ; the chances are it will slip and he will take another heat. After awhile he may succeed in sticking them together, but it will not be a solid weld. If you use borax give the pieces a couple of good blows, over the anvil, to knock all the borax off the scarfs before putting them together to weld. We THE SCIENTIFIC STEEL. WORKER. 43 often hear old smiths say, "there is nothing as good as borax for welding steel," but most smiths know better. Any of the welding compounds given in this work will give better results than borax, but borax is better than nothing for welding. There are several good welding compounds on the market which are patented, but for welding tool or spring steel com- pound No. 1 is the best I have ever used. All the compounds and solutions in this book are good and have been thoroughly tested. You need not be afraid to try any of them. If you follow directions you will be pleased with the results. When welding steel do not be afraid to use a little elbow grease. A few good, quick, hard blows are worth a hundred light ones ; if you cannot strike a blow that will do some good, do not strike at all ; just stand and look at it. Large tools are often made of soft steel and have a tool steel face welded on. This makes a good tool if properly done. To do this, first forge the soft steel to the desired shape, then heat it to a bright red and lay the cold tool steel in position and take a good welding heat on the two together. By first heating the soft steel to a bright red you will be able to get a good welding heat on both pieces without burning the tool steel. When ready to weld commence at one end or one side and work to the other ; weld it solid all over the first heat if possible. The high heat necessary to weld is an injury to the tool steel, and unless a good welding compound is used the steel 44 THE SCIENTIFIC STEEL WORKER. will show the effects of the high heat. A better way to make large tools is to fasten the tool steel face on with set screws. Some smiths prefer a split weld for steel, but I cannot recommend it only for thin, flat pieces. Any steel that I cannot weld without splitting cannot be welded at all. My objections to a split weld is, the inside piece is very liable to slip or draw forward in welding which will leave a hole or weak place, and will not look good. When welding tool steel to iron or soft steel, al- ways get a good, high heat on the iron or soft steel and as high a heat on the tool steel as it will stand without injury. Then commence welding on one side and work to the other, or commence in the mid- dle and work both ways ; never strike one side and then the other, for if you do the dross cannot get out, which will prevent solid welding. In some cases a poor weld may cost some one their life. Let your motto be a solid weld or none at all. If you wish to weld a very small piece to a large one, take a good welding heat on the large piece and only a red heat on the small one ; put them together and use the hammer smartly and the weld will be as good as if both pieces had been at a welding heat. I have often welded very small pieces onto large ones by taking a good welding heat on the large piece and not putting the small one in the fire at all. The heat from the large piece will put a welding heat on the small piece in a very few seconds. THE SCIENTIFIC STEEL WORKER. 45 When welding steel be careful to get a good, clean heat and do not use too much borax or welding compound. If you use borax be careful to knock off all melted borax from the scarfs before putting them together to weld. Some welding compounds give the best results if left on the scarfs, others should be knocked off the same as borax. Welding New Ends on Boiler Flues. Flare the long piece out, draw to a thin edge, fit the short piece inside ; make the lap about one-half inch long. Have a clean fire with a good body of fuel under the work ; heat the flue evenly, using a good welding compound, and have a heavy block of iron on the forge at the end of the short piece; this will keep the short piece from working out; when hot enough to weld tap it lightly on the end; then with a light hammer weld down the lap in the fire; do not remove it from the fire until welded. Annealing. The definition of the word annealing is to soften by heating and cooling slowly. The object of an- nealing steel is to make it soft enough to work easily, and to remove internal strains which always exist in steel that has not been annealed properly, which is the result of hammering or rolling. If these internal strains are not removed before the article is hardened, the chances are it will spring or crack in hardening. Internal strains are the only cause of 46 THE SCIENTIFIC STEEL WORKER. steel springing or cracking, and great care should be used to guard against strains in steel that is to be hardened. Uneven heating, uneven hammering and uneven cooling are the chief causes of internal strains. To anneal a piece of steel we heat it red hot and cool it slowly ; the longer it is cooling the softer it will be. Steel may be annealed by several different meth- ods, but in all cases it must be heated red hot and slow- ly cooled. In most shops a box of air slacked lime or wood ashes is used to cool the steel in. Either of these answers the purpose nicely, providing the box is large enough and its contents kept perfectly dry. The way I do is to heat a large piece of iron and put it in the lime and let it remain there while the steel is heating; then when the steel is red hot take the iron out and put the steel in the same place and cover it about six inches deep with the lime or ashes. In this way the lime or ashes will be hot and perfect- ly dry and good results will be sure to follow. In some shops they use a box of charred leather. If leather is used it is necessary to have a box with a good, tight fitting cover and keep it closed as much as possible. It is positively necessary to heat steel slowly and evenly for annealing and every other purpose. Lime, ashes or charred leather will be found to be a satis- factory means of annealing if the above directions are followed. THE SCIENTIFIC STEEL WORKER. 47 A very good method of annealing which I have used many times, with good results, is as follows : Take a piece of soft, pine board an inch thick and large enough to hold the pieces to be annealed; make a hole in the middle of the lime, place the board in the bottom of it ; then when the steel is hot ■enough put it on the board and lay another board the same size on- top of the steel and cover up with lime ; the pieces of board will smolder and keep the steel hot a long time. The process of cooling will be very slow and the results satisfactory. When steel must be annealed and cannot be al- lowed time enough to cool in lime, fairly good results may be had by placing the hot steel between two pieces of soft, pine board and allow it to cool with- out burying in anything. This will be found far better than water annealing. Water annealing has many advocates, but I cannot recommend it only in cases where the steel must be had for immediate use. Water annealing is done by heating the steel red hot and allowing it to cool in the air until every trace of red heat has disappeared when held in a dark place ; then plunged into water and left there until cold. If warm, soapy water or oil is used the steel will be softer than it would be if dipped into cold water. In annealing steel never heat it any hotter than you would to harden, and in hardening never heat any hotter than is necessary to produce the desired results. Also, be careful to heat the steel slowly and evenly all through ; for steel that is annealed at an 48 THE SCIENTIFIC STEEL. WORKER. uneven heat is very apt to spring or crack when it is hardened. There is ten times as much steel ruined by overheating and uneven heating as there is by any other causes combined. A man to be a success- ful steel worker must understand the nature of steel and keep his mind and his eyes on his work. Another way of annealing is to pack the steel in iron boxes, using charcoal for packing material. Put about one inch of pulverized charcoal in the bottom of the box, then put in a layer of the articles to be annealed ; but do not let them come within about one-half inch of each other or within one inch of the box ; fill in between the pieces with charcoal and cover them about one inch deep, then put in another layer of the steel and so on until the box is filled. If you do not have enough steel to fill the box, fill it up with charcoal ; put on the cover and seal it tight- ly with fireclay, then the box is ready to be put in the furnace. As a means of being able to know when the contents of the box are heated clear through, you should have several small holes drilled in the lid of the box near the center ; run a small rod of steel or iron in each hole long enough to reach the bottom of the box and project above the cover about two inches. When the box has had time enough to become red hot clear through pull out one of the little rods ; if it is red hot all over you will know the steel is also; but if the rod is not hot enough wait a while and pull out another rod and so on until the proper heat is reached, then put out the fire and let the work THE SCIENTIFIC STEEL WORKER. 49> cool down with the furnace, or the box can be re- moved from the furnace and buried in lime or ashes ; this is safer than leaving the box to cool in the furnace. If you leave the box in the furnace, watch it care- fully and be sure that the walls of the furnace are- not hot enough to cause the steel to become over- heated. If the furnace is too hot you should leave the door open a while or take the box out until the furnace gets cooled down some; then put the box back, close the door and let the work cool with the furnace, which will be very slow, and the result will be satisfactory. Charcoal and charred leather contains carbon and will help to keep steel from becoming decarbonized. Heating steel weakens jt and lowers the percentage of carbon unless something is used that will restore carbon to steel. Bone should never be used for an- nealing or hardening valuable tools, because bone contains considerable phosphorous which is very in- jurious to steel and is the worst impurity steel ever contains. All tools that are liable to spring or crack in hardening should be roughed out within about one- eighth of an inch of the finished size, then thorough- ly annealed again. If it is a tool that has a hole in it the hole or holes should be made but a little smaller than the finished size ; then after annealing the second time the holes can be bored out to size and the job finished up. 3>0 THE SCIENTIFIC STEEL WORKER. The object of annealing after the job is roughed out and holes made is to relieve all strains and to al- low the steel to expand and contract under nearly the same shape as it will when hardened. If this second annealing is properly done it will do away with a great deal of springing and cracking in hard- ening. If the piece springs in annealing do not •straighten it cold ; if it is not large enough to finish without straightening, heat it red hot and straighten it. If steel is hammered cold it will be sure to spring or crack when hardened. Machinists and tool makers often hammer steel cold, and then when it is hardened it springs and the man that hardened it .gets the blame. I have had lots of trouble in this way. Some machinists and toolmakers know about as much about steel and its proper treatment as a hog knows about Sunday school. All they know is to get the Job machined to size and shape regardless of how many strains they cause and how many square •corners they put in the job. Square corners always invite cracks. If an article cracks or springs in 'hardening the blame is always laid on the man that hardened it, or else on the steel, and perhaps the hardener gets discharged on the grounds that he -does not understand working steel. I was once dis- charged in this very same way. They hired a new man, he met the same fate. They kept right on Siireing and discharging until the men in charge came THE SCIENTIFIC STEEL WORKER. 51 to their senses and placed the blame where it be- longed. Machine shop foremen as a class are the most bullheaded men in the world. They think they know all about steel and every thing else. If a man had seventy-five years' experience in working steel, and should try to explain or tell a machine shop foreman anything about steel the chances are he would not listen to him, and about the next thing Mr. Steel Worker knew he would be out of a job and some other man that possibly could tell steel from iron would be working in his place. So be careful not to talk too much. Remember a still tongue makes a wise head. To be a successful steel worker you must study the nature of steel and know what it is liable to do un- der different conditions and how to avoid unde- sirable results, no matter whether it belongs to your department or not. In heating steel never let it come in contact with cast iron, for cast iron will extract carbon from the steel when they are both at a red heat. Never keep steel red hot any longer than necessary ; never blame the steel for bad results caused by your own careless- ness or the ignorance of the man that machined the job. Self-hardening steel can be annealed soft enough to machine fairly well by heating as hot as the steel will stand without injury, then burying it in a box of sawdust and burying box and all in lime or ashes. Now, in conclusion on this subject, I will 52 THE SCIENTIFIC STEEL WORKER. repeat, do not overheat or unevenly heat steel, and never subject steel to heat any longer than is actu- ally necessary for it to become evenly heated. Steel that has been kept at a high heat for an unnecessary length of time will be very coarse grained, of a dry, brittle nature, will not refine when hardened and will be entirely worthless for all sorts of cutting tools. Never allow steel to lay in the fire and "soak," as some smiths term it. As soon as the steel reaches the proper heat take it out of the fire immediately. Hardening and Tempering . Tool steel is hardened by heating it red hot and cooling it in water or other hardening bath. A bath that will absorb the heat the quickest will make steel the hardest. Clean water is generally used and gives fairly good results for hardening most tools. A very cold bath should never be used for hardening steel except when the bath is small and the article to be hardened is large. In such cases the bath will be- come warm before the steel is entirely cooled. A cold bath is very liable to cause the steel to crack, as the results of contracting too suddenly, or if it does not crack in hardening the sudden contraction is sure to cause internal strains which will cause the tool to break easier than it would if it had been hardened in a bath that had the chill off. The temperature of the hardening bath should be about sixty degrees F. If the bath is too hot, steel will not harden sufficiently for cutting tools. A very THE SCIENTIFIC STEEL WORKER. 53 good bath can be made by adding three pounds of salt to one gallon of soft water; there should be several gallons of the bath for small work and a bar- rel or more for large work. If the bath is small and there is several pieces to harden it will soon become too hot to properly harden the steel. There is no danger of getting the bath too large ; the larger the better ; the benefit gained by having a large bath is, it will remain at the proper temperature. If steel is heated uniformly and hardened in a bath of uniform temperature then all the pieces will be of the same degree of hardness ; this is a very important point which cannot be gained if the bath is too small. There are a great many hardening solutions in use which give better results than clear water or salt water. I have thoroughly tested the following baths and know them to be better than water or brine : HARDENING SOLUTION NO. 1. Corrosive Sublimate 3 oz. Salt 6 lbs. Soft Water 4 g a l. This solution is poison, so be careful. HARDENING SOLUTION NO. 2. Sal-Ammoniac 6 oz. Corrosive Sublimate 3 oz. Soft Water 4 gal. This is also poison, but is an excellent bath for all kinds of cutting tools. Draw the temper to the desired degree of hardness. 54 THE SCIENTIFIC STEEL WORKER. HARDENING SOLUTION NO. 3. Blue Vitrol 4 oz. Prussiate of Potash 4 lbs. Salt 6 lbs. Dissolve in one gallon of warm water, then add four gallons of raw linseed oil and one-half pound pulverized charcoal. This is an excellent bath for thin tools that must be hard and tough. If too hard, draw the temper. HARDENING SOLUTION NO. 4. Saltpeter 1 lb. Prussiate of Potash 3 lbs. Citric Acid 2 lbs. Carbonate of Iron 2 lbs. Salt 50 lbs. Soft Water 30 gals. The above is one of the very best solutions in use. The recipe was bought by the Kentucky Wagon Works for $100.00. In using these baths heat tho steel to a dark red and plunge into the bath ; keep the article moving in the bath until cold, then draw the temper to the desired degree of hardness. HARDENING COMPOUND NO. 1. Carbonate of Soda 1 oz. Carbonate of Potash 1 oz. Cyanide of Potash 1 oz. To be pulverized thoroughly and mixed together. Heat the tool to a dark red, dip the cutting edge in THE SCIENTIFIC STEEL. WORKER. 55 the compound, return to the fire a few seconds then plunge in salt water or any of the before-mentioned solutions. This will make a tool hard enough to cut glass, chilled cast iron or any thing else except a diamond. Draw no temper after using this com- pound. HARDENING COMPOUND NO. 2. Salt 2 lbs. Saltpeter ^ lb. Alum \ lb. Salts of Tarter \ oz. Cyanide of Potash 1 oz. Carbonate of Ammonia 6 oz. Pulverize thoroughly and mix together; keep* dry. This compound is intended for hardening- tools made of cast iron. Heat tool to a good red;: sprinkle thoroughly with the compound and plunge- in hardening bath. Draw no temper. Oil of different kinds is used to accomplish vari- ous results. No one bath will answer for all classes of work. Tallow or lard is an excellent bath for knife blades and all tools that should be tough as- well as hard. Linseed oil makes a good bath for thin tools that require a hard edge. To harden very small drills heat to a dark red,, plunge in a lump of tallow and beeswax, equal parts- Draw no temper. To harden small or thin articles without spring- ing, heat to a dark red and plunge into a box of dry,. 56 THE SCIENTIFIC STEEL WOKKEK. common soda. Leave it in until cold; if too hard draw the temper. To harden knife blades, heat to a dark red and plunge edge down in a cake of common, yellow soap. Draw no temper. Blades hardened in this way will hold an edge equal to a razor, and are not easily broken. With all these hardening solutions and compounds heat the steel no hotter than is necessary to produce the de- sired results, as there can never be anything gained in overheating steel. If steel is overheated it will become very coarse grained, and when broken it will look more like pig iron than it does like steel, and will be very brittle and will not hold an edge, no mat- ter how the temper is drawn or to what color it is tempered. All articles that are liable to spring should be plunged into the bath perfectly perpendicular and as quickly as possible. If you take a long mandrell or anything of that sort and plunge it into the bath on the slant, or put it into the bath slowly it will be al- most sure to spring. This is a very important point and should be remembered by every hardener. Un- even heating will also cause steel to spring in hard- ening. To harden long pieces without springing they should be roughed out nearly to the finishing size, annealed again to relieve the strains, then fin- ished to size. Be careful to keep the steel from springing while heating. To do this, heat slowly and THE SCIENTIFIC bTEEL WORKER. 57 evenly; turn the piece over often ; heat it inside of a straight piece of pipe or lay it on a straight piece of flat iron one inch thick ; lay the iron in the furnace first then lay your steel on the iron and heat steel and iron together. Be careful not to get steel any hotter than is necessary ; when it is hot enough take it out carefully and plunge it straight down into the bath as quickly as possible. The quicker you get it under water the better. If you have to harden tools that are liable to crack or spring, and they have not been annealed the second time, heat them red hot and lay them out until cold; then heat again and harden. This is not as good as annealing twice but is a great benefit. Hardening Milling Cutters or tools of irregular shape w T hich are liable to crack. A very good way is to take a dish and put in just enough water to cover the tool The teeth will harden quickly and the water will soon become hot so as to do away w T ith the danger of cracking. I have often used this method w T ith good results. A still better w T ay is to dip the tool in the hardening bath a few seconds, just long enough to harden the teeth or cutting surface ; then take it out and imme- diately plunge it into oil and leave it there until cold. I have hardened all kinds of thin and irregu- lar shaped tools in this way with satisfactory re- sults. In some shops they use a bath of oil and water. Of course the water will go the bottom ; 5 68 THE SCIENTIFIC STEEL WORKER. then when the tool is dipped it will pass through the oil first then into the water. This works nicely on some kinds of tools, but the best and safest way is to dip them in the water first and then in the oil as de- scribed above. To harden a piece of steel that has a deep hole in it, and it is desired to have the walls of the hole hardened the entire depth, it is necessary to force water to the bottom of the hole until the piece is en- tirely cold. To do this, get a piece of pipe about half the size of the hole; place it in the hole and dip both into the hardening bath; as soon as the article is under water commence forcing water through the pipe and do not stop until the article is cold. The pipe should go to within one-half inch of the bottom of the hole, and should be kept as near in the center as possible so that the water will come up all around alike. In hardening steel the amount of heat neces- sary varies with steels of different make and steels of different percentage of carbon. To accomplish dif- ferent results the steel makers put other hardening elements into steel besides carbon. The lowest heat at which a piece of steel will harden in a satisfactory manner is called the refining heat. When a piece of steel is hardened at this heat, if you break it you will see the grain is very fine and the steel will be very hard and strong. Heating steel red hot and cooling it quickly not only makes it hard, but also makes it brittle, and the higher the heat the more brittle the steel will be. THE SCIENTIFIC STEEL WORKER. 59 When a tool is hardened and found to be too hard or too brittle, it is then necessary to reheat it so as to reduce the hardness and brittleness. This reheating is called tempering, or drawing the temper. This may be done in different ways. By heating a large piece of iron and laying the article to be tempered on the hot iron until the proper color appears ; then remove it from the hot iron and allow it to cool in the air or quench it in oil or water ; oil gives the best re- sults, but water is generally used. Before drawing the temper it is necessary to polish one or more of the surfaces so the color can be seen ; the temper can be drawn by holding the article over the fire or in hot oil ; when oil is used it is necessary to have a ther- mometer partly immersed in the oil so the bulb will be at a level with the work. It is best to put the work in the oil before it is heated, then heat the work and oil together, or else warm the work first then put it into the hot oil. Cold pieces of steel should not be put into hot oil because the sudden ex- pansion would be liable to crack the article. When I commenced this work I intended to have a colored tempering chart in it but gave it up be- cause I found it to be impossible to get the correct tints produced on paper, so will give a written de- scription of temper colors and the number of degrees of heat necessary to produce each color, and the proper colors for all kinds of tools. The following is a correct table of temper colors : THE SCIENTIFIC STEEL WORKER. COLOR TEMPERING CHART. Color Light Straw Full Straw Very Dark Straw Light Purple Dark Purple Blue Pale Blue or Green 430 degrees. 460 490 530 550 610 630 Lathe and planer tools for brass, draw no color at all; for cast iron, very light straw; machine steel, steel castings, tool steel and wrought iron ma- chine tools should be drawn to a medium straw color; mill picks, scribers and scrapers, draw no color at all ; just heat the tool to about 400 degrees so as to re- lieve strains, but not hot enough to draw the slight- est color ; taps, very light straw ; dies, dark straw ; reamers, full straw; twist drills, full straw; milling cutters, from a light to a very dark straw; slotter tools, purple or blue; knurling tools, purple ; shear knives, from a dark straw to blue ; cold chisels, blue ; screw-drivers, let the blue run clear out; wood work tools, straw color ; granite tools, light straw ; marble tools, straw ; limestone tools, purple ; sandstone tools, blue ; clay picks, blue ; hammers and sledges, from a straw to a purple. Remember that colors do not indicate how hard a tool is, only under the right kind of circumstances. Colors simply indicate the amount of heat there is in the steel, nothing more or less. We can draw any THE SCIENTIFIC STEEL WORKEfi. 61 color on a soft piece of iron or even on a piece of tin. In drawing colors there are several things that must be taken into consideration — the quality of the steel, the nature and temperature of the bath, and the heat the steel was hardened at. When you harden a piece of steel be sure you get it hard so that a good, fine file will not take hold of it at all, and be careful not to heat steel any hotter than is necessary to produce this hardness. The better the article is polished the better the colors will show. Always leave tools as hard as they will stand. To make a tool extra tough draw the color a second time. After the color is drawn on a tool it should be cooled off enough to keep it from becoming softer. If articles are left in water very long after tempering the color will fade, and will disappear entirely if left in water a few hours. If you want color to remain on the article dip it in oil just long enough to cool it. For tools that must be very hard, draw no color ; heat them slowly to about 400 degrees to relieve strains, but not hot enough to draw any color, and allow it to cool in the air. If the color should start dip it into water or oil a few seconds. In this way you will leave the tool just as hard and a great deal tougher than it was when first hardened. Steel is a bad con- ductor of heat, and when a piece is dipped into a bath the surface cools and contracts first; the interior cools slower and as it contracts the tendency is to pull away from the outside and enormous strains are developed; but when they are evenly distributed the 62 THE SCIENTIFIC STEEL WORKER. steel is strong enough to resist them, but if there is more strain in one portion than another the steel is liable to crack. Tools with sharp corners in them will be far more liable to crack than they would if the corners were rounding, for square corners always invite strains. If you have many pieces to temper lay them on a hot piece of iron; for taps, reamers, drills, etc., heat a large nut or something of the sort, then pass the tool back and forth through the hole in the hot iron ; turn it over often and watch the color closely. In drawing the temper on milling cutters and all articles having a large hole in the center, heat a round bar to a light red and put the article on the hot bar ; this will draw the center the most and is the best way of drawing the temper when hot oil cannot be had. Remember that all hardening baths should be kept in a clean barrel or tank, and should be kept covered when not in use to keep out dirt and also to keep the contents from evaporating. Soap will ruin the best bath; oil and grease should be kept away from the hardening bath. The object in using salt water or other hardening solution is to harden the steel at a lower heat than can be done in clear water; and by so doing we leave the steel a great deal stronger and better in every way than it would be if heated higher and hardened in water. If we take tw T o pieces of steel from the same bar and heat one to a dark red, the other to a light red and harden them both in the same bath, the one that THE SCIENTIFIC STEEL WORKER. 63 was the hotter will be a great deal more brittle than the other one ; or, if we take two pieces from the same bar and harden one in cold brine and the other in warm water or oil, the one that was hardened in the brine will be very much harder and more brittle. Again, if we take two pieces, one of low carbon steel and the other high carbon and heat them both alike and quench them in the same bath, the high carbon steel will be very much the harder. All these things must be considered when drawing temper. If you should accidentally let an article get too hot lay it out and allow it to cool in the air until perfectly cold, then heat again to the proper red and harden. Do not lay it out until it cools down to the proper hardening heat and then quench, for if you do the steel is left in a worse condition than it would have been if quenched when first removed from the fire. I have often seen men lay overheated steel out until it cooled down to the proper heat then harden it, but it should never be done. By laying the over- heated article out and allowing it to cool in the air it will contract slowly ; then when it is reheated and hardened at the proper heat the steel will refine and will be nearly as good as it ever was. That is if it was only slightly overheated; of course, if it was heated to a welding heat it will not refine unless it is thoroughly hammered; and if badly overheated it will never be anywhere near as good as it was before. Never let anyone make you believe that any com- pound or solution will make burned steel as good as 64 THE SCIENTIFIC STEEL WORKER. it was before it was overheated or burned. Acci- dents will happen to the best of us, and it is well to know how to make the best of them. In heating steel always use a furnace if possible and avoid fuel that contains sulphur, for sulphur is very injurious to steel. A muffle gas furnace is the best method of heating steel ; good, hard coke is the best fuel for an ordinary furnace. When heating must be done in an ordinary forge with coal for fuel, char the coal thoroughly, and for such tools as taps, drills, reamers, etc., heat them inside of a piece of pipe with one end closed tightly; but this is not necessary for cold chisels, lathe tools, etc. In hard- ening lathe and planer tools, cold chisels, etc., heat them back from one to three inches from the end ; dip them so as to leave heat enough in the tool to draw the temper on the cutting surface ; avoid any sharp dividing line in the heat; have the heat even back a little further than the tool is required to be hard, and in dipping do not hold the tool at one cer- tain depth but move it up and down and sideways in the water so as to have no sharp dividing line be- tween the hard and soft parts, as it is these sharp di- viding lines which cause so many tools to break. Just back of the hardened portion the steel is usu- ally very soft; it is simply water annealed; this leaves steel in the very weakest condition possible, then when the tool is used it is very liable to bend or break at the dividing line between the hard and soft portions. If care is used in heating and hardening THE SCIENTIFIC STEEL, WORKER. 65 this difficulty will be overcome. Uneven heating is more liable to cause an article to spring or crack than overheating is; overheating causes steel to be- come very brittle, coarse grained and unfit for use. I have seen men who thought themselves good steel workers, overheat steel and abuse it in every way and then cuss the steel or the man who used the tool, when the fault wa- their own and they did not have sense enough to know it. A man to become a successful steel worker should work steel only. He should watch his heats carefully, and after harden- ing should try the work with a good, sharp, fine file so as to be certain the steel is properly hardened and to ascertain how low a heat the steel will harden at. There is a great difference in steel. Some of the high carbon steel will harden at a very low red, while the lower carbon steels require a higher heat. Steel that will not harden at a good red is not fit for cutting tools of any kind. Steel for taps, dies, ream- ers, drills, machine tools, etc., should harden at a dark red sufficiently to resist a good file. Milling cutters, reamers, threading dies and drills should be tempered so that a good, fine, sharp file will take hold of them slightly. Taps should be tempered so a file will catch but very little if any. Long arbois, mandrells, reamers, etc., that are liable to spring in hardening, should be made of a good grade of steel. Do not cut the bar cold. After cut- ting, heat the piece to a good red all over ; stand it on end and give it two or three good blows on the end 66 THE SCIENTIFIC STEEL WORKER. with a heavy hammer or sledge, depending upon the size of the piece ; this will relieve strains caused by- rolling or hammering; then thoroughly anneal it. The steel should be large enough so that all the de- carbonized surface will be removed in machining. In all cases the steel should be at least one-eighth of an inch larger than the finished tool. Arbors and mandrells should be hardened and re- heated slightly, but not enough to start the slightest color. Hardening Anvils. To harden anvils or other large articles it is necessary to have a large bath, or one that has an overflow and inlet of fresh water so as to keep the bath from getting too hot. Another very important point is to get a nice, even heat and keep it moving in the bath until nearly cold, unless you can arrange so as to have a stream running on the face of the anvil. If a piece of red hot steel is plunged into a bath and held still, steam will form around it and keep it from hardening properly. This is a very im- portant point, especially when large pieces are to be hardened. Articles that are liable to spring in hardening should be moved up and down in the bath but should not be moved sideways. Hardening and, Tempering Hammers. Hammers and sledges should be heated evenly all over, but only harden the faces ; leave heat enough in the middle to draw the temper in both ends. THE *CIEXTLFIU STEEL WORKER. 67 Hammers and sledges should be tempered so that a good file will take hold on the face. A hammer or s edge that you cannot file will be found to be too hard. It is far better to have ~a hammer too soft than too hard. Before drawing the temper on any article have the surface polished nicely. If the surface is poorly pol- ished the colors will not show nearly so well as on a surface that is well polished. If the polish is uneven the colors will not be uniform. The part that is poorly polished will show a darker color than the part that was well polished. Tempering in Hot Oil. Drawing the temper in hot oil is the best way ever invented, and is generally used in connection with a gas furnace. Articles can be tempered to any degree to an absolute certainty in this way. Melted tallow is generally used for this purpose for it is capable of taking very high temperature, and can be kept at any temperature required for drawing temper by regulating the gas. The temperature of the oil can be determined by a thermometer partly im- mersed in the bath so that the bulb will be on a level with the work ; in this way the exact heat required can be obtained which eliminates the element of guess-work from the process providing the work has been hardened uniformly. If you wish to draw an article to a straw color, adjust the heat of the bath to 460 degrees F. and dip 68 THE SCIENTIFIC STP^EL, WORKER. the articles to be tempered in the hot tallow and keep them there long enough to become evenly heated clear through ; that is all that is necessary. It will do no harm to leave the artices in the bath longer. The temper cannot get below a straw color as long as the bath remains at 460 degrees F. no matter if you should leave them in all day. For an article one- fourth of an inch thick, six minutes will be long enough; three-eighths of an inch, eight minutes; one-half inch, ten minutes. The thicker the steel the longer it will take for the heat to penetrate it. If the steel is not uniformly hardened it cannot be evenly tempered by this method or any other. A man cannot work steel successfully unless he has his mind and eyes on his work. I have often seen men put a piece of steel in the fire, turn on the blast and go to talking to some one and let the steel get to a white heat. Then they will say, "well, that is a little too hot, but it is not burned." A poor excuse, better than none. If a man cannot keep his mind on his work, he should work at something besides spoiling steel. Never complain about the steel not being good unless you know and can prove that it really is poor steel, or not the right kind of steel for that purpose. First be sure you are right and know what you are talking about, then do not let any one bluff you. Every man who has had much experience in hard- ening steel has seen what is generally called water cracks. These cracks are liable to occur when hard- THE SCIENTIFIC STEEL WORKER. 69 filing articles that have thin edges and heavy bodies. Cold chisels sometimes crack in this way. These cracks never run straight but are always curved, and nearly always on only one side of the article. The cause of this sort of crack is the same as all others, viz., strains; and strains are either caused by un- even heating, uneven hammering or uneven contra- tion of the steel in cooling. Some tool makers, machinists and foremen are in the habit of calling any and all kinds of cracks in steel "water cracks." If a tool should break square in two three months after it had been hardened they would declare it to be a water crack, no matter how the fracture appeared, and regardless of how the tool had been used. It is useless to argue with such men for they imagine they know it all ; but in re- ality they are like the dutchman said : " Never knew nothing and always will." There are a great many wrong theories advanced regarding steel and its proper treatment. A large per cent of the toolsmiths are old blacksmiths who are not able to do heavy work, so they are put on the tool fire. These old gentlemen think it is quite an honor to be promoted to toolsmith, and soon become imbued with the idea that they are expert steel workers. These old grandpas are always fuU of whims and all have their pet hobby regarding steel. One of them with whom I am acquainted claims that steel shouM be hardened in ice water. Another tells us that long, round articles can be hardened without springing by 70 THE SCIENTIFIC STEEL WORKER. stirring the bath in a circle as fast as possible and plunging the hot steel in the centre of the -whirl. He says "the water turning around it will keep it straight." Another says: "To keep steel from springing or cracking, put three or four handfulls of soot and one handfull of lime in the bath." What ridiculous nonsense. Strains are what causes steel to spring and crack. If a piece of steel has a strain In it, all the lime and soot in America cannot remove it, and stirring the bath in a circle will not help the matter in the least. Another expert tells us to dip all tools towards the north. Never condemn anything unless you have thor- oughly tested it and found it worthless. Never advance a theory that you cannot prove. Never argue about steel with a man who knows it all, for it is a useless waste of words. Never conceive the idea that you know all about steel. Never be in too great a hurry when heating steel. Never overheat or unevenly heat steel. Never use a very cold bath for hardening steel. Never become careless when working steel. Never forget to keep your mind and eyes on your work. Never expose steel to heat any longer than neces- sary. Never forget the instructions given in this little book, and you will become a successful steel worker. THE SCIENTIFIC STEEL WORKER. 71 Case Hardening. Case hardening is a subject that has received but little attention. It is generally understood that case hardening is the process of making the surface of a piece of soft steel or iron very hard. Webster gives the following definition: "To harden the outer part or superficies, as of iron, by converting it into steel, while the interior retains the toughness of malleable iron." It is worth while to remember that the part to be case-hardened must be converted into carbon steel before it can be hardened. This can be done in vari- ous ways. Soft steel or iron will, under favorable circumstances and proper treatment, become carbon- ized (or converted into carbon steel) one-eighth of an inch deep in twenty-four hours' treatment. For articles that only require a slight surface hardening to prevent the corners from battering easily, as in cap screw heads, slot-headed screws, nuts, bolt heads, etc., the process is very simple. All that is neces- sary is to heat the article to a bright red and sprinkle it with pulverized Prussiate of Potash or Cyanide of Potash. Return it to the fire a few sec- onds, then harden it in cold water or brine. This will make the surface hard enough to resist the best file, but of course does not harden deep because the steel or iron was only exposed to the carbonizing ele- ment a few seconds. A better way to case-harden with Cyanide of Pot- ash is to place the articles in a large ladle and put in 72 THE SCIENTIFIC STEEL WORKER. enough Cyanide to cover them all ; put the ladle in the fire and melt the Cyanide and heat to a red ; keep it red hot for some time, for the longer the articles are kept red hot in the Cyanide the deeper they will harden. A large number of pieces can be hardened at one time in this way. When they have been in the red hot Cyanide long enough take them out and plunge them in the bath as montioned before. Re- member Cyanide of Potash is rank poison, so be care- ful. Do not put any wet article into melted Cyanide ; if you do, it will fly in all directions. Another way to case-harden is to pack the arti- cles in an iron box with granulated raw bone and charred leather or charcoal; or bone and small pieces of leather may be used with good results. Place about one inch of bone and leather, or bone and charcoal, as the case may be, in the bottom of the box, then put in a layer of the pieces, but do not let them touch each other or come within one-half inch of each other or within three-fourths of inch of the sides of the box ; fill in between the articles with the packing material and cover them about three-fourths of an inch deep ; then put in another layer and so on until the box is filled to within two inches of the top ; then fill up with packing material and seal the lid tightly with fire clay. It is a good plan to have about four small holes drilled in the centre of the box lid and run a wire through each hole down be- tween the articles to the bottom of the box. The wires should be long enough to reach the bottom of THE SCIENTIFIC STEEL WORKER. 73 the box and project above the lid about two inches. Put a little fire clay around each wire where it goes through the lid. The wires should be as large as will go through the hole easily. The holes should be about three-sixteenths of an inch in diameter. When this is done, place the box in the furnace and heat thoroughly to a good red and let it remain at that heat long enough to become heated evenly clear through ; then pull out one of the wires ; if it is red hot you will know that all the articles in the box are of the same heat. If only a thin surface hardening is wanted the work will be ready to harden as soon as it is brought to a good red; but if you want a deeper hardening it is necessary to keep them red hot for some time. If the first wire you remove does not show red hot, wait a while and draw another and so on until the proper heat is reached. When ready to harden, remove the box from the furnace, take off the lid and dump the contents of the box into a sieve, shake out the packing material and plunge the arti- cles into the bath as quickly as possible. Do not let them go into the bath all in a pile or they will not harden properly ; scatter them around as much as possible. If the pieces are large they should not be dumped into the bath, but should be removed from the box one at a time and kept moving in the bath until nearly cold. If you wish the articles to be strong and hard take them out of the box and let them cool in the air ; then heat them again to a red and harden the same as tool steel, but draw no tem- 6 74 THE SCIENTIFIC STEEL WORKER. per. Articles treated in this way will show as fine a grain as tool steel ; but if quenched when taken from the box they will be coarse grained and will not be nearly as strong as they would if allowed to cool in the air and then reheated and hardened. You have all seen articles which were colored in case-hardening. To do this, we must first have the articles nicely polished and perfectly clean. If you wish to produce colors, do not quench in any harden- ing solution ; use clean, soft water. When the work is ready to harden, it is necessary to force air through the water so that it will bubble. The way I do this is to put a piece of small pipe in the bath and blow through it, then harden the article in the bub- bling water. Work cannot be colored nicely if heated in a dirty fire, or exposed to the air or fire while heating. Nice colors can only be obtained by heat- ing the articles in a muffle furnace, or in an air-tight box, or piece of pipe, or in melted Cyanide as de- scribed before. Colors can also be had when the articles are packed in carbonaceous materials as de- scribed before, only use charred bone instead of raw bone. Articles will show the colors better if they are left in the water only just long enough to harden them, then removed while quite warm and cooled in oil. If thin or small pieces are to be case-hard- ened, and you want them to be strong and not brit- tle, harden them in oil instead of water. The Harveyizing method of case-hardening is as follows : Pack the articles in boxes as described be- THE SCIENTIFIC STEEL WORKER. 75 fore, only use charred leather or wood charcoal ; do not use bone in this method ; keep the work red hot for about eight hours, then remove the boxes from the furnace; when they are cold remove the work and harden the same as tool steel. If you wish to harden extra deep, the articles should be packed in the boxes and heated twice. Before hardening this will carbonize the steel deeper and better than one pack- ing. Soft steel case-hardened in this way will be as fine grained and as hard as tool steel. I have hard- ened milling cutters made of open hearth steel by this method, which worked as good as cutters made of tool steel. If you wish to case-harden part of an article and not the balance, copper plate the part you want soft; the carbon will not penetrate the copper, or the parts you want soft may be covered with fire-clay to pro- tect it from becoming carbonized. Another way to accomplish the same results is to machine to size only the parts you want hard, then pack in a box and car- bonize. When cold, machine the part desired soft. This will remove the carbonized surface ; then harden it; of course, the part that was machined after car- bonizing will not harden. For extra large pieces, or pieces that require an extra depth of hardening, it is best to use coarse bone and leather scrap and keep them red hot all day, or even two days. If one day's heat is not sufficient, let the work cool over night, then remove 76 THE SCIENTIFIC STEEL. WORKER. from the box and pack again in fresh material and return to the furnace. When you harden large pieces of any kind keep them moving in the bath until nearly cold. If you do not keep large pieces moving while hardening, the results will not be satisfactory because the steam will keep the bath from coming in close contact with the steel and it will not cool quickly enough to harden properly. For case-hardening cultivator shovels and plow shears, use yellow Prussiate of Potash. To pre- vent plow shears from warping hammer evenly on both sides and dip straight in the bath. Do not overheat steel ; give the work plenty of time to be- come carbonized. Follow these directions closely and you will be successful in case-hardening. Thermite Welding. Thermite is a newly discovered compound which will instantly develop heat of 5400 degrees Fahren- heit, which is more than sufficient to melt granite. All other processes of producing heat are not to be compared with thermite. With its enormous heat large rails have been welded in a second, and great steel shafts have been welded almost instantly. It can be macfe to explode with tremendous power, or to work almost silently with appalling results. Ther- mite is a mixture of aluminum filings and Oxide of Iron. It is the discovery of Dr. Hans Goldschmidt. Its remarkable powers were recently demonstrated THE SCIENTIFIC STEEL WORKER. 77 before the Columbia University Chemical Society. The discovery was made in an effort to produce pure Metallic Chromium, the metal much employed to give extra hardness to steel. This metal is not usually pure, and contains a considerable quantity of car- bon. It had been known that when a mixture of aluminum filings and the Oxide of Chromium were heated in a furnace, a violent explosion would follow, owing to the intensity of the chemical action. Dr. Goldschmidt argued that in such cases Metallic Chro- mium must be found. After a series of experiments the problem was solved. When the aluminum filings were thoroughly mixed in a crucible with Oxide of Chromium, a teaspoonful of ordinary flashlight pow- der and Peroxide of Sodium was placed on the mass. This acted as a "primer." A match was applied. There was a bright flash, followed by a glow and gen- tle flame. When cold, the crucible was broken, and at the bottom was found Metallic Chromium at least 90% pure. Above it, and easily separated, was a slag of Aluminum Oxide or artificial corundum. Dr. Goldschmidt soon discovered that Manganese could be equally well obtained in this way — merely substituting Oxide of Manganese for the Oxide of Chromium. Next, the chemist substituted Oxide of Iron for Oxide of Chromium, and when touched off by the flashing primer the slag of the corundum 78 THE SCIENTIFIC STEEL WORKER. spurted out liquid and naming. It was a blinding spectacle ; bubbling like water, it ran pure metallic iron and sank to the bottom in a dazzling, molten mass so intensely brilliant that the chemist was tem- porarily blinded Though the contents of the cruci- ble flowed out at a temperature of 5,400 degrees Fahrenheit, the outside of the crucible could be held in the bare hand almost immediately, because the de- velopment of the heat was too rapid to affect sur- rounding bodies unless kept in contact with the molten mass longer than it remains in the crucible. Thus thermite was discovered. Steel rails are welded by this process in Berlin, Munich, Hamburg, Casse, and other German cities. It is also a success in welding pipes into continuous lengths, miles long if necessary. For pipes only the slag (not the molten metal) is allowed in contact with the pipe joint. Thermite is also a success for welding large shafts. All that is necessary is to place the pieces, which are to be welded, in the de- sired position, only leave them from three-eighths to one inch apart, depending on the size of the shaft. A mold is then placed around the shaft and the molten metal allowed to flow into the joint. The in- tensity of the heat will, in an instant, put a welding heat on the ends of the shaft which will unite with the thermite metal. When cold it will be found to be one solid mass, and equally as strong at the weld as in any other part. THE SCIENTIFIC STEEL WORKER. 79 A Chemical Mixture which will cut a hole in a file or other hardened steel or iron which cannot be drilled successfully : Sulphate of Copper .... 1 oz. Alum \ oz Pulverized Salt \ teaspooful. Nitric Acid 20 drops. Vinegar 1 gill. To cut a hole in steel with this mixture, first make a hole in a cake of beeswax the size you want the hole in the steel ; then heat the beeswax a little and place it on the steel ; then fill the hole with the mixture. If the above mixture is applied to steel, which has a polished surface, and washed off quick- ly, it will produce a beautiful, frosted appearance. How to Re-cut Files by a Chemical Process. Dissolve four ounces of common soda in one quart of water; make enough of this solution to cover the files and boil them in it for half an hour; then take out, wash and dry them ; then stand them endways in a jar of sufficient depth and fill up the jar with rain water and put in four ounces of Sulphuric Acid to each quart of rain water. If the files are coarse they will need to remain in the solution about twelve hours; but for fine files eight hours will be sufficient. When you take them out wash them clean and dry them quickly and put on a little sweet oil to keep 80 THE SCIENTIFIC STEEL WORKER. them from rusting. Files may be re-cut in this way two or three times. The solution may be kept and used as long as you see action take place when you put the files into it. Keep it tightly covered when not in use. The object of boiling the files in the soda solution is to remove all grease and dirt. The action of the acid thins the teeth and leaves a sharp edge. By using this method you can get double the amount of service. The cost of re-cutting is very small. Writing on Metals. For writing on iron, steel, brass, copper, etc., use the following mixture : Muriatic Acid 1 oz . Nitric Acid \ oz. Mix together. Cover the article you wish to write on with beeswax ; when cold write plainly what you want in the beeswax with a sharp pointed piece of steel ; be sure to get clear down to the metal and clean all the wax out of the letters. Then apply the solution with a feather ; fill all the letters carefully ; let it remain from two to ten minute6, ac- cording to the depth of letters desired ; then put on some water which will dilute the acid and stop the action ; now clean off the beeswax and put on a little oil. Either of the acids alone will cut iron or steel, but it requires them both to cut brass, copper, nickel or silver. Hard soap may be used instead of bees- THE SCIENTIFIC STEEL, WOKKBB. 81 wax, but the wax is the best. If you wish to write- on some article that is rounding, so that the acid will not stay in the letters, you can cover the article on all sides with wax; then dip it in the so'ution in such a way that the acid will cover the letters. This mixture will cut a hole in steel or iron which is too hard to drill. Paraffine may be used in place of beeswax with fully as good results as soap. How t<> Build a Furnace,. A furnace for heating steel, for hardening and an- nealing should be in every shop, for it is impossible to get a satisfactory heat in a forge for hardening tools. A forge is all right for cold chisels, lathe and planer tools, etc., but for taps, dies, reamers, shear knives, milling cutters, etc., a furnace should always be used. A furnace can be easily and cheaply built and will pay for itself in a short time. The furnace should be built of fire brick and of proper size to suit the class of work which it is to be used for, and should be arched over the top and have an iron door about twenty-four inches wide by twelve or fourteen inches high. The door should be lined with fire brick, and should have a one and one- half inch hole in the center so that the operator can see the work. The door should be nicely balanced by means of a lever and weight which should be above the door and of sufficient height to be out of the way. There should be a small rod attached to* the lever so that the operator can open the door by "82 THE SCIENTIFIC STEEL WORKER. pulling the rod. If the door is properly balanced it will remain in any position, and will be easily opened •or closed. The fire bed is an important feature in this kind of a furnace. Any ordinary grate bars with one-half inch openings will do. The bars should be firmly set so as to make a solid, level bed. The fire bed should be about two feet from the floor; the fore plate should be five or six inches above the : grate bars. Another important feature is the stack, which should be of sufficient size and height to give the furnace a good draft, and should have a good damper so it can be closed perfectly tight. Hard coke is the only satisfactory fuel for this kind of a furnace. Kindle the fire with wood, then fill the furnace up level with the fore plate with small pieces of coke. Leave the damper open until the furnace gets to the proper heat then close it and put in the work. This kind of a furnace does not require any blast. If you wish to use it for heating or forging purposes leave the damper open. A welding heat can be ob- tained if desired, but for hardening and annealing purposes be careful not to get the furnace too hot, and keep the damper closed, or nearly so, while the steel is heating. For heating small articles, lay them on a piece of iron about one-fourth of an inch thick, and of suffi- cient size to hold the pieces; then place them in the furnace on the plate; for heating large shear knives, THE SCIENTIFIC STEEL WORKER. 83 etc., a heavier plate is necessary. Turn the steel over while heating so as to get a perfectly even heat. This kind of a furnace is not as good as a muffle gas furnace, but is a great deal cheaper and will answer the purpose very well. The entire expense of making such a furnace would not exceed $50. I have used furnaces of this description on all classes of work with good results. Brazing. Brazing consists of uniting two pieces of metal wi^h brass, copper, nickel or silver. Brass filings, soft sheet brass or spelter is what is generally used. To braze two pieces together we must first see that there is no dirt or grease on the articles, and that the surface, where the brazing is to be done, is bright and free from rust. We must also fix up some means of holding them together just as they are to be after they are finished. Now, when this is done, heat the joint red hot; put on a little powdered borax and then the brass filings which will quickly melt and run into the joint and all around it; turn the article over often to keep the brass from running off; as soon as you see the brass has melted and run into the joint, remove it from the heat and cool in the air or .water. A band saw is an article that often break-* and can easily be brazed so it will be as strong as ever. I have brazed hundreds of them and never had one break where it had been brazed. To braze a band 84 THE SCIENTIFIC STEEL, WORKER. saw, first file or grind the ends to a thin point; of course, only grind or file on the flat sides ; thin both ends down to knife edge; taper them back about one inch ; lap them together as far as you have tapered them ; clamp the saw so as to hold it in line and right where you want it; have your clamp about ore inch from the joint on each side ; now take a thin piece of sheet brass the width of the saw and about one-fourth of an inch longer than the splice is to be ; put the piece of brass between the lapped ends of the saw; put a little powdered borax on top of the saw; have a pair of tongs with heavy bits, about one inch square; heat them nearly to a welding heat, then grasp the saw at the splice with the hot tongs; hold it tightly until the brass melts, then remove the tongs carefully and allow the saw to cool; then file off the rough spots and smooth it up and your saw is ready to run again. It is any easy matter to braze steel or wrought iron, but cast iron is very difficult to braze and cannot be done by the ordinary way of brazing. To braze cast iron we must first use a coating over the surface to be joined. The best coating is the Oxide of Cop- per made into the constituency of varnish and ap- plied to the surface with a brush. Mix the Oxide of Copper with some suitable liquid to make the coat- ing. The effect of this coating is to reduce the car- bon on the surface of the cast iron to be brazed so that it passes somewhat into the nature of steel. Without this treatment the surface of cast iron, when THE SCIENTIFIC STEEL WORKER. 85 heated, become slippery and will not braze. This re- duction of carbon will penetrate for some distance into the cast iron. Heat in a muffle gas furnace or with a brazing torch ; use brass filings, which will melt and run into the joint, at about 1,800 degrees F., and it will make a solid job fully as strong as solid cast iron. Blow holes in castings can be filled in this way. First clean the hole and then coat it all over with the Oxide Varnish ; heat it up to the brazing tempera- ture and fill the hole full of melted cast iron ; use a little spelter or brass filings; this will make the cast- ing just as solid as it would have been if it had never had any blow hole. Brackets or any kind of pro- jection can be brazed onto castings in this way. THE SCIENTIFIC STEEL WORKER. DIAMETER AND CIRCUMFERENCE OF CIRCLES EXPLANATION OF THE FOLLOWING TABLES. To find the circumference of a circle when the di- ameter is given, we multiply the dameter by 3.1416. A shorter method is to multiply the diameter by 3 1-7; or multiply the diameter by 22 and divide by 7. The following tables commence at one inch and advance by one-eighth of an inch up to twenty feet. In making rings or bands of any size of iron or steel, we must add the thickness of the iron to the diame- ter and get the circumference on that size. Example : If you wish to make a ring 40 inches in diameter out of 2^ inch square iron, to the diame- ter, 40 inches, add the thickness of the iron, 2^ inches, which equals 42^ inches, or 3 ft. 6^ inches. Refer to the tables for the circumference of a 3 ft. 6£ inch circle; you will find it to be 11 ft. and f inches. Cut off your iron 11 ft. f inches long, scarf the ends, bend and weld it and you will have a ring 40 inches in diameter inside measure. The thicker the iron the more it will take up in bending. It will take 19 ft. If inches of iron, one inch thick, to make a ring 6 ft. in diameter; and will take 19 ft. lOf inches of iron four inches thick,. THE SCIENTIFIC STEEL WORKER. 87 to make a ring 6 ft. in diameter. A circle 7 ft. in diameter will be 22 ft. in circumference. When making rings always add the thickness of the iron to the inside diameter and refer to the tables for circumference. The tables will be found correct and useful to any man who has rings or bands to make. 88 THE SCIENTIFIC STEEL WORKER. TABLE NO. 1.- 1 in. to L ft. 4% in. -DIAM. CIR. DIAM. CIR. DIAM. CIR. DIAM. CIR. IN. FT. IN. IN. FT. IN. FT. IN. FT. IN. FT. IN. FT. IN. 1 0. 31 5 1 3| 0. 9 2. 44 1 1 1 3. 4J H 0. 31 51 1 4 o. n 2. 4f 1 1-1 3. 54 H 0. 31 51 1. H 0. 94 2. 5 1 14 3- 5| if 0. H 5| 1 H 0. 9f 2. 5| 1 if 3. 6 H 0. H 51' i. H o. n 2. 5J 1 i* i 3. 6f If 0. 5 H 1. 5| 0. Of 2. 64 1 if 3. 6j If 0. 6* 5f 1. 6 0. 9f 2. 6f 1 if 3. n 11 0. 51 51 1. 6| o. n 2. 7 1 11 3- Tf 2 0. H 6 1. 6J 0.10 2. 7| 1 2 3. 8 21 0. if 61 1. 7^ 10i 2. 7| 1 H 3. 8| H 0. 7 H 1 H O.lOi 2. 8i 1 n 3. 8| H 0. n 6| 1 8 0.10| 2. 8^ 1 2| 3. n U 0. n 61 1. 8| O.lOi 2. 9 1 n 3. n 2f 0. H 6| 1. 8| 0.10| 2. 9f 1 2* 3. 91 2f 0. H 6f l. h O.lOf 2. 9f 1 2i 3.10| 21 0. 9 61 l. H o.ioi a.ioj 1 21 3.10f 3 0. n 7 1.10 0.11 2.101 1 3 3.11-1 31 0. n H l.lOf o.ni 2.101 1 31 3. Hi 8i 0. 10J n l.lOf 0.114 2ilf 1 34 3111 31 0. 10£ n 1.111 O.llf 2.11| 1 3f 4. 04 3* 0. 11 n 1.111 oni 3. Oi 1 »* 4. Of 3| 0. 111 n 1 111 O.llf 3. 0| 1 3f 4. 1 3f 0. Hi 7| 2. Of O.llf 3. 01 1 3f 4 If 31 1. 01 n 2. 0| 0.11J 3- 14 1 31 4. 11 4 1. 01 8 2- 11 1. 3. If 1 4 4. 24 H 1. 01 81 2. 1* 1. 0^ 3. 2 1 H 4. 2f H 1. If 81 2. 11 i 04 3. 2i 1 44 4. 3 *t 1. If 81 2. 2j 1. Of 3. 21 1 If 4. 8| H 1. 21 81 2. 2| 1- 0i 3. 3i 1 H 4. 3| H 1. 21 8| 2. 3 1. Of 3. 3f 1 If 4- 4f 4f 1. 21 8f 2. 3£ 1. 0| 3. 4 1 If 4. 4i 41 1. 31 81 2. 8| 1. OJ 3. 4f 1 11 4. 5 THE SCIENTIFIC STEEL, WORKER. TABLE NO. 2.— 1 ft. 5 in. to 2 ft. 8% in. CIR. DIAM. ; CIR. DIAM. j CIR. DIAM. FT. IN. FT. IN. I FT. IN. FT. IN. j FT. IN. FT. IN. H H 7 n n H 9 H n n n n n H H 6f n n 8 5. 8f H 1| H if if 6. 64 6. 6J 6. 7| 6. 8i 6. 84 6. Hi 6. 9i 5 H H 5f 5* 4. 84 4. 8J 4. 9J 4. 9| 4.10| 4.104 4.1of 4.11| 10 104 lOf 104 10| lOf 104 5. 9^ 5. 94 5. 9 J 5.101 5.10| 5.11 5.114 5. 11J 2.2 2. 24 2.2J 2.2| 2.24 2.2| 2.2f 2.2J 6. Q{ 6.10 6 . 104 6.10J 6. Hi 6.1M «i 64 6| 6f 4. 11| 5. 5. Of 5. 0J 5- li 5. If 5. 2 5. 2| 11 14 HI HI 14 n| ill 11* 04 of 1 if if 6. 2J 6. 2f 6. 3 2.3 2. 34 2.31 2.3| 2.34 2.3f 2.3f 2.34 7. Of 7. U 7 7 7 7. 2| 7. 2| 7. Si H 2 9M 7a H 7| 7* 7J 24 34 8* 4 4f &4 04 0i Of o* Of Of of 6. 3# 6. 3f 6. H 6. H 6. ±i 6. 5# 6. H 6 H 2 4 8.4J 2.44 2.4| 2.44. 2.4| 2.4f 2.4| 4f 64 «* s S-l 84 84 90 THE SCIENTIFIC STEEL WORKER. TABLE NO. 3.-2 ft. 9 in. to 4 ft. 0% in. DIAM. FT. IN. CIR. FT. IN. DIAM. FT. IN. 9 n 2 2 2 2. 9f 2. 9| 2. 9| 2. 9f 2. 9J 8. 7| 8. 8 8. 8| 8. 81 8. 9^ 8. 9| 8. 10 8.10| 3.1 3.LJ 31i 3. If 3.1i 3. If 3. If 3.1J CIR. FT. IN. 9. 8i 9. 8| 9. 9 9. 9| 9. 9f 9.104 9.101 DIAM. FT. IN. CIR. FT. IN. 3.5f 3.5f 3.5J 10. 8f 10. 9| 10. 9! 10. 9J lO.lOf lO.lOf 10.14 io. Hi DIAM. FT. IN. 9* 9i 9| 9* 9| 9f 9J CIR. FT. IN. 11. 9| 11. 9f n.ioi 11.10! ll.iof 11. Hi ll.llf 12. 01 2.10 2.101 2 . 10i 2.10| 2.10! 2.10| 2.10f 2.101 8.10| 8.111 8.1H 9. 9. Of 9. Of 9. 11 9. 11 3.2 3.2! 3.2i 3.2f 3.21 3.2f 3.2f 3.21 9.1l| 9.11f 10. 0! 10. 01 10. 01 io. if 10. If 10. 21 3.6 3.6! 3.6! 3.6f 3.6! 3.6| 3.6f 3.61 10 11* 11. o« 11 Of 11 H 11 i* 11 n 11 H 11 H 3.10 3.10! 3.10! 3.10f 3.10! 3.10| 3.10f 3.101 12. 0! 12. 01 12. li 12. If 12. 2 12. 2| 12. 21 12. 3! 2.11 2.111 2. Hi 2.H| 2.11! 2.11J 2.11f 2.111 9. 11 9. 2f 9. 2f 9. 31 9. 3! 9. 31 9. 4| 9- H 3.3 33! 3.3! 33| 33! 3.3| 3.3f 331 10. 2! | 10. 21 10. 3! 10. 3| 10. 4 io. i! 10. 41 11 H 3.7 3.7! 3.7! 3.7f 37! 3.7f 3.7| 3.71 11 3 11. 3! 11. 31 11. 4! ii H li ii 5 H 11. 5f 3.11 311! 3 11! 3. 11| 3.11! 3 llf 8.11J 3.111 12. 3| 12. 4 12. 4f 12. 4f 12. 5! 12. 5| 12. 6 12. 6| 3. 3. 0! 3. 0! 3. Of 3. 0! 3. Of 3. Of 3. 01 9. 5 9. 5! 9. 5| 9. 6! 9. 6f 9. 7 9. 7f 9. 71 3 4 3.4! 3.4! 3.4f 3.4! 3.4f 3.4f 3.41 10. °7? 10. 6 10. 6f 10. 61 i n 7 l u 10. H 10. 8 10. 8| 3.8 3.8! 3.8! 3.8f 3.8! 3.8f 3.8f 3.81 11. 6! 11. 6f 11. 7 11 11 11 11 11. 81 H 81 8! 4 4 4 4 4 4 4. Of 4. 01 0! 0! of 0! o# 12. 6f 12. 71 12. 7! 12. 71 12. 8f 12. 8f 12. 9! 12. 9! THE SCIENTIFIC STEEL WORKER. 1)1 TABLE NO. 4.-4 ft. 1 in to 5 ft i% in. DIAM. FT. IN. 1 i* n 4. 1* 4. If 4. If 4. 1* CIR. FT. IN. 12 9* 12 lOf 12 Hf 12 11* 11 11* 12 in 13 o* 13 Of DIAM. FT. IN. 4 4 4 4 4 4 4.5f 4.5* H H H H CIR. FT. IN. 13 10* 13 10* 13 in 13 u* 14 14 04 14. o* 14. H DIAM. FT. IN. 4. 9 4. 9* 4. 9* 4. 9f 4. 9* 4. 9| 4. 9f 4. 91 CIR. FT. IN. 14.11 14. 11^ 14 ll| 15. 0* 15 15 15 15 0j 1 1| 1* DIAM. FT. IN, 5.1 5.1* 5.1J 5. If 5.1* 5.1| 5.11 5.11 4. 2 4. 2* 4. 2* 4. 2| 4. 2-| 4- 2| 4. 2f 4. n 13. 1 13. H 18. i* 13. H 13. n 13. 3 13. H 13. 3| 4.6 4.6* 4 6* 4 6| 4.6* 4.6f 4.6f 4.61 14. 1* 14. 2 14. 2* 14. 2* 14. 3* 14. 3* 14. 4 14. 4| 4.10 4.10* 4.10* 4.10| 4.10* 4.10| 4.10| 4.10* 15. 2* 15. 2| 15. 3 15. 3| 15. 3f 15. 4* 15. 4* 15. 4* 5.2 5.2* 5.2* 5.2| 5.2* 5.24 5.2f 5.21 3 4 4 4 4 4 4. 34 4. 3f 4. 3* H H 3* 13. 4* 13. 44 13. 5 13. 5| 13. 5f 13. 6* 13. 6* 13. 7 4.7 4.7* 4.7* 4.74 4.7* 4.74 4.7| 4.7* 14. 4f 14. H 14. H 14. 51 14. 6* 14. 6f 14. n 14. H 4.11 4.11* 4 11* 4.H4 411* 4.114 4.114 411* 15. 54 15. 54 15. 6* 15. 6* 15. 6* 15. 7* 15. 74 15. 8* 5.3 5.3* 5.3* 5.34 5.3* 5.34 5.34 5.3* 4 4* 4* 44 4* 44 44 4* 13. 74 13. 7| 13. 8* 13. 8* 13. 8* 13. 9* 13. 94 13.10* 8* 8* 84 84 14 n 14 8* 14 8f 14 9* 14 9* 14 9* 14. 10* 14. 104 5. 04 04 Of 04 04 5. Of 5. 0J 15 8* 15 8* 15 9* 15 94 15 10 15 104 15 10* 15 11* 4 44 H *i H H 5.4f 5.41 92 THE SCIENTIFIC STEEL WORKER. TABLE NO 5. 5 ft. 5 in. to 6 ft. 8% in. DIAM. CIR. DIAM. CIR. DIAM. CIR. DIAM. CIR. FT. IN. FT. IN. FT. IN. FT. IN. FT. IN. FT. IN. FT. IN. FT. IN. 5 5 17. Oi 5 9 18 • of 6 1 19. If 6 5 20 11 5.51 17 Of 5. 91 18 • H 6 1| 19 11 6.51 20. 21 5.51 17 1 5 91 18 ■ U e H 19 21 6 51 20 2| 5.5f 17 If 5 9| 18 • n 6 If 19 H 6.5| 20 3 5 H 17. If 5. 9J 18 ■ 2| 6 li 19 n 6 54 20. 34 5 5f 17 2* 5 9| 18 • 2f 6 If 19 n 6 5f 20 3| 5.5f 17. 2* 5. 9| 18 • H 6. If 19 H 6 51 20. 41 5.5J 17. H 5 9J 18 . 3J 6.1J 19 4 6 51 20 4| 5 6 17. 8| 5.10 18 H 6 2 19 44 6 6 20 5 5.61 17 H 5.101 18 H 6 21 19 41 6.61 20. 5f 5.61 17. H 5.101 18 H 6.21 19 H 6.61 20. 51 6.6f 17. H 6.10| 18 5 6 2f 19 5| 6.61 20. 61 5.6| 17. *l 6.10* 18 H 6.24 19 6 6 64 20. 6| 5 6f 17. H 5.10| 18 H 6.2f 19 <*! 6.6f 20. 7 5.6| 17 H 5 10| 18 6i 6.2f 19 61 6.61 20. 7| 5.6J 17 6 5. 101 18 6| 6.2| 19 n 6.61 20 7f 5.7 17. 6i 5.11 18 7 6.3 | 19 n 6.7 20. 81 5.71 17. «* 5.14 18 H 6.31 i 19 8 6 71 20. 8i 5.7J 17. H 5.111 18 n 6 31 i 19 8| 6.71 20 9 5.7| 17 7| 5.11# 18 8i 6 .3| 19 81 6.7| 20. 9f 6.7* 17. 8 5. Hi 18 8S 6.34 19 H 6 74 20. 9f fi. 7| 17. 8| 5. ll| 18 9 6.3| 19 9| 6.7| 20 . 101 5.7| 17. 8| 5.111 18 9| 6.3f 19 10 6 71 20 104 5.7J 17 9i 5- H| 18 9f 6.3J 19 lOf 6.71 20.1. » 5.8 17. 9| 6. 18 10^ 6.4 19 101 6 8 20. U| 5.81 17 10 6. 01 18 1.81 17. 10| 6. 01 18 11 641 19 111 6.81 21. 01 5.8| 17 lOf 6. Of 18 us 6.4f 19 11J 6.8| 21. 04 5 8| 17 m 6. 04 18 llf 644 20 Of 6.84 n. 01 5.8| 17. H* 6. 0| 19 n 6.4| 20 oi 6.8| 21 11 5 8j 18 6. Of 19 Oi 6 4f 20 li 6.81 21. if ■5. 8 J 18. OS 6 0i 19 0| 6.41 20 li 6 81 21. 2 THE SCIENTIFIC STEEL WORKER. 98" TABLE NO. 6.-6 ft. 9 in to 8 ft. 8% in. CIR. FT, IN. 2i. n 21 21 21 21 21 21 21 n H 4 H DIAM. CIR. FT. IN. FT. IN. 7 1 22. 3 1M 22. 3f 7.1i 22. 3* 7.11 22. 4^ 7.H 22. 4f 7.1| 22 5 7.14 22. 5| 7.1$ 22. 5| DIAM. FT. IN 7.5 7-.5-J 7.5| 7.5* 7.5| 7.5f 7.5* CIR. FT. IN. 23. H 23. 4 23. H 23. H 23. H 23. 5^ 23. 6 23. 6| DIAM. FT. IN. 9 n n 7. 9f 21 . 5* 21 . 6 21 . 6| 21 . 6} 21. 7* 21 . 7| 21 . 8 21. 8f 7.2 7.2* 7 2* 7 2f 7.2f 7.2* 22 . 6* 22 . °* 22 . 7 22. H 22 . H 22. Si 22. 8* 22. 81 7.6 7.6* 7.6J 7.6f 7.6-J 7.6| 7.6# 23. °f 23. n 23. 7* 23. n 23. n 23. 8f 23. 9* 23. 9* 7.10 7.10* 7.10± 7.10| 7.10* 7.10f 7l.0f 7.10* 21. 8f 21. 94 21. 9* 21. 9* 21.10| 21.10f 21.11* 21.11| 7.3 7.3* 7.3^ 7.8| 7.3* 7.3f 7.3f 7.3* 22 n 22 9f 22 10* 22 10* 22 10* 22 Hi 22 111 23 7.7 7.7* 7 .71 7 .7| 7.7* 7 .7| 7.7f 7.7* 23. 9* 23.10| 23.10f 23 11 23.11* 23.1l| 24. 0i 24. Of 7.11 711* 7.11| 7. 11| 711* 7.11| 7.11| 7.11* 22. 22. FT. IN. FT. IN. FT. IN. , FT. IN. : FT. IN. 17.5 ! 54 8 I 17 9 55 n 18 1 56. 9f 18.5 i 57.10* 17.5^ i 54 9 17. 9* 55. H 18 H 56. 10* 18 5* i 57.10| 17. 5^ 54. H 17. 9± 55 9| 18. 1± 56. 10* 18 H 57.11 17. 5{i 54 9| 17. 9| 55 10| 18.1| 56. 10* 18 H 57.11| 17 . 5* i 54 . 10* 17. 9^ 55. lOf 18.1* 56. Hi 18 H i 57.11f 17 ■5|:' 54. 10* 17. 9f 55 "i 18.1| 56. H| 18 H i 58 . 0* 17.5f i 54 10* 17. 9f 55. lit 18 If 57. 18 5j i 58 . 0| 17 . 5| i 54 . Hi 17. 9* 55. n| 18. 1* 57. o* 18 H 58. 1 17.6 i 54. ii* 17.10 56 0i 18.2 57 o* 18 .6 58. If 17 . 6-J i 55 o* 17.10* 56 0| 18.2* 57 H 18 •6* 58 . 1* 17 . 6± i 55 . o* 17. 10± 56. 1 18. 2± 57 if 18 .6* 58. 2* 17. 6|; 55. n 17.10f 56. H 18.2| 57 2 18 ■6| 58. 2| 17.6i> 55. H 17.101 56. n 18. aj 57. 21 18 •6* 58. 3 17. 6f: 55. i* 17.10| 56. n 18.2| 57. n 18 ■«l 58. 3| 17. 6f i 55. 2 17.10J 56. 2| 18. 2f 57. H 18 6f 58. 3f 17 . 6| | 55 . n 17.10* 56. 3 18. 2 J 57. Sf 18 6* 58. 4* 17.7 : 55. n 17.11 56. 8* 18.3 57. 4 18 7 58. 4* 17.7* | 55. H 17.11| 56. »i 18. 3* 57. H 18 H 58. 4* 17. 7±; 55. H 17. Hi 56. H 18.3* 57. 4 18 n 58. 5§ 17.7|i 55, 4 17.11| 56. H 18.3| 57. H 18 n 58. 5| 17.7| i 55. H 17. Hi 56. 5 18.3* 57. H 18 H 58. 6* 17.7|i 55. 4J 17.H| 56. H 18. 3| 57. 6 18 H 58. 6* 17.7|j 55. H 17.11f 56. 5f 18. 3f 57. 6| 18 7f 58. 6* 17. 7* | 55. H IT. 11* 56. 64 18.3* 57. 61 18 n 58. 7i 17 8 ! 55. 6 18. 56. 6i 18.4 57. 7* 18 8 58. 7f 17.8*': 55. «! 18. 0* 56. 7 18.4* 57. 7* 18 84 58. 8* 17. 8^; 55. Of 18. 0± 56. n 18.4* 57. n 18 8i 58. 8* 17. 8f i 55. 7* 18. Of 56. n 18.4| 57. 8f 18 8| 58. 8* 17.8-1 i 55. H 18. 0* 56. H 18.4* 57. 8f 18 84, 58. 9* 17.8JS 55. 8 18. 0| 56. H 18.4| 57. 9* 18 8|i 58. 9f 17.8fi 55. H 18. 0| 56. H 18. 4f 57. 9* 18 8fi 58.10 17.8*: 55. 8f 18. 0* 56. 9| 18.4* 57. H 18 8| i 58.10| 102 THE SCIENTIFIC STEEL WORKER. TABLE NO. 15.- 18 ft . 9 in to 20 ft. 0% in. DIAM. CIR. DIAM. CIR. DIAM. CIR. DIAM . ; DIAM. FT. IN. FT. IN. FT. IN. FT. IN. FT. IN. FT. IN. FT. IN. ! FT. IN. 18. 9 58.104 19.1 59. Hf 19.5 61. 19. 9 i 62. 04 18. 9* 58.11! 19.14 59. HI 19.54 61. Of 19. 94: 62. 1 18. 9i 58.11| 19.11 60. 04 19.5! 61. Of 19. 9! 62. If 18. 9| 59. 19.1| 60. 04 19.54 61. H 19. 94 62. If 18. 9i 59. 0| 19.14 60. 1 19.54 61. H 19. 94 62. 24 18. 9| 59. Of 19. If 60. If 19.54 61. 11 19. 9| 62. 24 18. 9} 59. 14 19. If 60. If 19. 5f 61. 2! 19. 9f 62. 2| 18. 9 J 59. If 19.14 60. 24 19.54 61. 2f 19. 94 62. 31 18.10 ' 59. 2 19.2 60. 24 19.6 61. H 19.10 62. 3f 18.104 59. 2f 19.24 60. n 19.64 61. H 19.104 62. 4 18.10! 59. 2f 19.21 60. H 19.6! 61. H 19.10! 62. 44 18.10| 59. 34 19.24 60. 3f 19.6f 61. H 19.10f 62. 44 18.104 59. 34 19.24 60. H 19.64 6L. H 19.104 62. 51 18.10| 59. ± 19.2| 60. H 19.64 61. 5 19.104 62. 5| 18 . 10f 59. 4f 19. 2f 60. ±* 19. 6f 61. H 19.10f 62. 6 18.10J 59. 4f 19.24 60. 54 19.64 61. 51 19.104 62. 6f 18.11 59. 54 19.3 60. 5f 19.7 61. 64 19.11 J62. 64 18.114 59. 54 19.34 60. 64 19.74 61. 64 19.114 i 62. 7! 18.111 59. 5| 19.31 60. 64 19.7! 61. 7 19.111 162. 7| 18.11| 59. 6f 19.3| 60. H 19.74 61. 74 19 HI 62. 8 18.114 59. 6f 19.34 60. 7! 19.74 61. 71 19.114 62. 8f 18.11| 59. 74 19.34 60. n 19.74 61. 81 19.114 62. 8f 18.11| 59. 74 19. 3f 60. 8 19. 7f 61 84 19.11f 62. 94 18.114 59. 74 19.34 60 84 19.74 61 9 19.114 62. 94 19. 59. 84 19.4 60. 81 19.8 61. 9f 20. 62.10 19. 04 59. 8| 19.44 60. n 19.84 61. 9f 20. 04 62.10f 19. 01 59. 9 19.4! 60. 94 19.8! 61. 101 20. 0! 62.10f 19. Of 59. 9£ 19.4| 60. 10 19.8| 61. 104 20. Of 62.114 19. 04 59. 9| 19.44 60. 104 19.84 61. Hi 20. 04 62.114 19. Of 59.10! 19. 44 60. 10f 19.8| 61. Hi 20. Of 62.114 19. Of 59.10| 19. 4f 60. 114 19. 8f 61. nf 20. Of 63. Of 19. 04 i 59.11 19.44 60 111 19.84 62 04 20. 0| 63. Of THE SCIENTIFIC STEEL WORKER. 103 ANGLE IRON To find a uniform principle which can be applied in all cases of bending angle iron of any width and thickness, has been found to be more difficult than any of the preceding rules. While there is an end- less variety of sizes of this kind of iron, each influ- encing the expansion and contraction in bending, it has been found during the course of numerous ex- periments, as well as from information obtained from practical men, that bars of angle iron of the same size and length may give results widely different, accord- ing to the heat and manner of working them. In angle iron the mass of metal forming the root, or corners, offers an obstacle to the expansion and con- traction of the bar when it is placed on the inside or outside of the ring. The following rule, constructed on the principle of measuring the root, will be found correct in all sizes generally used, viz., one and one- half to four inches. RULE FOR FINDING THE CIRCUMFERENCE OF OVAL RINGS. Add the greatest length and the greatest width together and divide by two. Refer to the tables for circumference. 104 THE SCIENTIFIC STEEL WORKER. RULE FOR BENDING ANGLE IRON. Rule for rings with flange on the outside — To the inside diameter add twice the thickness of the root (measure from the outer corner to the inner one) and refer to the tables for circumference. Example: What length of angle iron three inches square and one-half inch thick will it require to form a ring three feet in diameter with the flange on the outside? Angle iron of the above size will be found to be one inch thick in the root or corner; then twice that thickness equals two inches ; this added to three feet equals three feet and two inches, the circumference of which is nine feet and eleven and three-eighths inches. Rule for rings with flange on the inside \ m From the outside diameter of the ring subtract twice the thickness of the root and refer to the table for circumference. Example: What length of angle iron two and one-half by three-eighths will form a ring two feet, six inches in diameter outside meas- ure? The thickness of the root in this size is seven- eighths of an inch, which multiplied by two gives one and three-fourths inches, which substracted from two feet six inches, leaves two feet four and one- quarter inches, the circumference of which is seven feet four and three-quarter inches. THE SCIENTIFIC STEEL WORKER. 105 TABLE NO. 16.— Weight of steel per foot. Square Round Octagon Size Lbs. Size Lbs. Size Lbs. £ .05 I- 04 1 .04 A .12 A .09 3 16 .10 i .21 i 4 .17 1 4 .18 A .33 A .26 A .28 I .48 t .38 I .40 A .65 A .51 A .54 1 .85 i .67 i 2 .70 A 1.08 A .85 _9_ 16 .89 1 1.33 I 1.04 f 1.10 H 1.61 1 1 T7 1.27 11 T6 1.33 3 4 1.92 f 1.50 t 1.58 « 2.24 i Iff T6 1.76 13 T6 1.83 1 2.60 1 2.04 i 2.16 « 3.06 15 16 2.35 15 16 2.48 3.40 2.67 2.82 li 4.30 1 i 3.38 H 3.56 li 5.31 H 4.17 H 4.40 If 6.43 if 5.05 if 5.32 H 7.65 i i 1 2 6.01 H 6.34 H 8.98 If 7.05 if 7 32 if 10.40 li 8.18 1 3 8 64 1 7 11.90 l* 9.38 1 t 1 8 9.92 2 13.60 2 10.17 2 11.28 2i 15.40 2| 12.05 2i 12.71 2i 17.20 2 4 13.60 2i 14.24 21 19.20 2| 15.10 2f 15.88 a* 21.20 2i 16.68 2* 17.65 106 THE SCIENTIFIC STEEL WORKER. TABLE NO. 17.— Weight of steel per foot. Square Round- Octagon Size Lbs. Size Lbs. Size Lbs. 2% 23.50 2% 18.39 2% 19.45 2% 25.70 2K 20.18 2% 21.28 2% 28.20 2% 22.06 2% 23.28 3 30.60 3 24.10 3 25.36 m 33.13 3M 26.12 3^ 27.50 3M 35.90 3^ 28.30 3^ 29.28 3% 38.54 3K 30.45 3% 32.10 3^ 41.60 3^ 32.70 sy 2 34.56 3^ 44.57 3^ 35.20 z% 37.05 3M 47.80 3% 37.54 sk 39.68 4 54.40 4 42 72 4 45.12 4M 61.40 4K 48.30 4M 50.84 4^ 68.90 4^ 54.60 4M 56.90 4% 76.70 4M 60.30 m 62.52 5 85.00 5 66.80 5 70.60 5M 93.70 5M 73.60 5M 77.80 h% 102.80 5K 80.80 b% 85.15 5M 112.40 5M 88.30 5% 93.12 6 122.40 6 96.10 6 101.45 6^ 143.60 6K 113.20 6*6 117.12 7 166.40 7 130.80 7 138.24 8 217.60 8 170.88 8 180.48 9 275.60 9 218.40 9 227.84 10 340.00 10 267.20 10 282.40 11 41120 11 223.00 11 340.60 12 489.60 12 384.40 12 405.80 THE SCIENTIFIC STEEL WORKER. 107 TABLE NO. 18.— Weight of steel per foot. Inch X % % X % % 1 X .214 .428 .641 % .267 .534 .802 ' 1.069 % .321 .641 .^62 1.283 V.603 % .374 .748 1.122 1.496 1.870 ' 2.244 l .427 .855 1.283 1.710 2.138 2.565 m .481 .962 1.443 1.924 2.405 2.886 ' 3.848' iH .534 1.069 1.603 2.138 2.672 3.206 4.275 W .588 1.176 1.763 2.351 2.939 3.527 4.703 IX .641 1.283 1.924 2.565 3.206 3.848 5.130 i% .695 1.389 2.084 2.779 3.473 4.168 5.558 m .748 1.496 2.244 2.993 3.741 4.480 5.985 i% .802 1.603 2.405 3.206 4 008 4.809 6.413 2 .855 1.710 2.565 3.420 4.275 5.130 6.840 2M .908 1 817 2.725 3.634 4.542 5.451 7.268 %H .962 1.924 2.886 3 848 4.809 5.771 7.695 2% 1.015 2.031 3.046 4.061 5 077 6.092 8.123 2M 1.069 2.138 3.206 4.275 5.344 6.413 8.550 2% 1.122 2.244 3.367 4.489 5.611 6.733 8 978 2% 1.176 2 351 3.527 4.703 5.878 7.054 9.405 3 1.283 2.565 3.848 5.130 6.413 7.695 10 260 3^ 1.389 2.779 4.168 5.558 6.947 8.336 11.115 3^ 1.496 2.993 4.489 5.985 7.481 8.978 11.970 %% 1.603 3.206 4.809 6.413 8.016 9.619 12.825 4 1.710 3.420 5.130 6.840 8 550 10.260 13 680 4K 1.817 3.634 5.451 7.268 9.084 10.901 14.533 4^ 1.904 3.848 5.771 7.695 9.619 11.542 15.390 4K 2.031 4.C61 6.092 8.123 10.153 12.184 16 245 5 2.138 4.275 6 413 8.650 10.688 12.825 17.100 5K 2.244 4.489 6.733 8.978 11.222 13.466 17.955 5^ 2.351 4.703 7.054 9.405 11.756 14.108 18 810 BM 2.458 4.916 7.374 9.833 12.291 14.749 19.665 6 2.565 5.130 7.695 10.260 12.825 15.390 20.520 108 THE SCIENTIFIC STEEL WORKER. TABLE NO. 19.— Decimal Equivalents. Eighths, Sixteenths, Thirty-seconds and Sixty-fourths of an inch for use in connection with Micrometer Calipers. Eighths h =.125 i =.250 | =.375 i =.500 | =.625 | =.875 Sixteenths T V=.0625 T \=.1875 ^=.3125 tV= 4375 T \=.5625 H=-6875 ff=.8L25 if=.9374 Thirty-seconds sV=.03125 &=. 09375 £,=.15625 ? V= -21875 &= .28125 Thirty-seconds Con. H= 34375 H= .40625 H=. 46875 ^=.53125 i|= 59375 H=. 65625 ||= . 71875 ||= . 78125 ||= . 84375 ||= . 90625 H=. 96875 Sixty-fourths ^=.015625 &=. 046875 &= .078125 e\=. 109375 &=. 140625 ii=. 171875 if =.203125 if=.234375 H=- 265625 if=. 296875 Sixty H fourths Con. = .328125 = .359375 =.390625 = .421875 = 453125 = .484375 = .515625 = .546875 =.578125 = .600375 =.640625 = .671875 = .703125 =.734375 = .765625 = .796875 = 828125 = .859375 =.890625 = .921875 = .953125 = .984375 THE SCIENTIFIC STEEL WORKER. 109 TABLE NO. 20.— U. S. Standard Bolts and Nuts. u % o H; H F be so : ° -i *-i - S erg- : S'8, C CD S : 8p& C5-B CT CD CD m- of PB tf F* GO O tnOJhtJS MCD cd e oB 1 tf • SB San- Inches Inch Inches Ins. Ins. Ins. Ins. Inches A 24 .156 A A i A 1 1 20 .185 if A A i 1 3 "8 16 .294 A H A 1 liV tV 14 .344 H 1 I A 1 1 1 4 1 13 .400 » 7 "8 TV 1 11 A 12 .454 1 5 5^ 1 1 2 A 1A 5 8 11 .507 H H A f if 3 4 10 .620 li H f 3 4 2 £ 9 .731 t 1* t It 2| 1 8 .873 27 3~2 if 1 1 2f li 7 .940 H 114 1 H 3 11 7 1.065 J A 2 H li 31 if 6 1.160 1A 2A H if 31 11 6 1.284 1t 5 6 2t 5 6 If 31 if 51 1.389 1A »A 11 if 4i 11 5 1.490 m 2| if if 41 n 5 1.615 it 2| l! if 4f 2 H 1.712 125 A ?2 8* if 2 5f 2-1 H 1.962 Hi 8* 2 2i 5f 4 2.175 *H 31 2i 2i 6f 2| 4 2.425 2*1 41 2i 24 7 3 3i 2.628 2| 4| 2| 3 n si 3i H 2.878 Q27 ^3"2 4| 8i 34 3i 3| 3.100 8A 5f 3i 3i 8f 31 3 3.317 3 T 5 6 5f 3i 3| 9| 4 3 3.566 Q 9 °T"6 61 3| 4 101 4i 2f 3.825 311 6i 4 4i 10 1 4i 2| 4.027 *A 6* 44- H ill 41 2f 4.255 4i U 4i 4f 12 5 21 4.480 41 7f 4f 5 12 | 51 2| 4.730 4| 7* 5 51 13i 5* 2f 5.053 5A 8f Bi 5i 181 5| 2f 5.203 5i 8f 5^ 5f 141 6 2i 5.423 5A n Bi 6 15 f 110 THE SCIENTIFIC STEEL WORKER. TABLE NO. 21.— Different Colors of Iron and Steel Caused by Heat. DEG. FAR. 977 Iron and steel becomes very dark red. 1292 " ' blood red. 1472 " ' dark cherry red. 1657 " 1 cherry red. 1832 " ' bright cherry red. 2012 " ' dark orange. 2192 " ' bright orange. 2372 " ' white. 2552 " 1 brilliant white welding heat. 2830^ Iron and steel becomes dazzling white m e It i n g* heat. From 1657 to 1832 is the proper heat for hardening steel. " 2000 " 2500 " ll " u " welding steel. " 2600 u 2700 " " u " " welding wrought iron. TABLE NO. 22.— Properties of Metals. ^ ^ ptV otv Melting Point o-afw !.?§ Tensil Deg. Far. a' S- a' ct- Strength Aluminum . . . 1140 166.5 .0963 15000-30000 Antimony. . . . 810—1000 421.6 .2439 1050 Brass 1500—1780 523.2 .3027 30000- 45000 Copper 1930 552 .3195 30000- 4000O Gold (pure). . 2100 1200.9 .6949 20380 Cast Iron .... 1900-2200 450 .2604 20000- 30000 Wrought Iron 2700—2830 480 .2779 35000-60000 Lead 618 709.7 .4106 1000— 3000 Nickel 2000 548.7 .3175 50000 Silver" 1800 665.1 .3791 40000 Steel ." 2370—2680 475 489.6 458.3 436 5 .2834 .2652 .2526 50000—120000 Tin 5000 Zinc 7 80 3500 Note.— The variations are due to different qualities. THE SCIENTIFIC STEEL. WORKER. Ill TABLE NO. 22.— Sizes of Drills for Pipe Taps. Nominal Diam. of No. Thr'ds Size Tap Drill Per Inch. H i I S""2~ 28 M 7 16 18 K n 18 % 3 4 14 % 3 1 3~2 14 1 1/6 \\% m H U% iy 2 If ny 2 2 2A n% 2y 2 211 8 3 Q 9 °S2 8 sy 2 Q25 °?2 8 4 4ff2 8 4M 4|| 8 5 5f 8 6 6H 8 7 V. 8 8 8tV 8 10 10|| 8 0.12 THE SCIENTIFIC STEEL WORKER. Conclusion. In closing I wish to impress upon the minds of my many readers that I am not a retired steel worker. I cannot boast of having had forty years experience in working steel, for I am less than forty years old. I •commenced working steel when eighteen years of age and have been at it ever since (fifteen years). While writing this book I worked for The Youngstown Iron Sheet and Tube Company six days per week, and wrote in the evenings. I intend to work steel as long as health is spared to me, and will never get too old to learn. In conclusion I will repeat : Do not overheat steel for any purpose ; remember that the forging heat is too hot for annealing or hardening. Always heat steel slowly and evenly, but never under any circum- stances subject steel to heat any longer than is actu- ally necessary. As soon as it is properly heated remove it from the fire. Never hammer a flat tool on the edge during the finishing heats, and never ham- oner steel at a black heat. When hardening steel keep it in the bath until cooled thoroughly clear through. FEB 19 1904