Knowing that many blacksmiths are troubled with dull and battered dies that are unfit for business, I venture to give my method of putting them in order.
If the dies are too badly worn or defective, take a piece of good cast-steel, forge it down nearly to the size of the dies and cut it off a trifle longer. Get a piece of one and one-half or two-inch gas pipe, eight or ten inches long, plug up one end, heat the pieces of steel to cherry red, pack them in the pipe with fine charcoal, plug the other end, heat the whole to a good red and hold the heat fifteen or twenty minutes, then bury the whole well up in the fire over night. They will be soft enough to work quite well next morning. Then dress them up with the file to the proper size and length; cut the end slots with the hack saw and fit them nicely in the plate; remove them and file notches in the faces large enough so the tap can be started steadily; return to the plate and cut good full threads with a sharp tap of the desired size.
Then cut out the throats with the hack saw and file, and temper as follows: Heat the dies to a cherry red and drop them into a vessel of raw linseed oil. When cool take them out, polish, and draw on a hot iron to a medium dark straw color.
I find that, as a rule, it is best to buy taps, yet sometimes one is wanted for a special job, and it is inconvenient to buy it. Taps may be made on the same general principles, that is, by making the steel the proper size and shape, cutting the threads and then working out the grooves with the hack saw, chisel and file. Care must be taken in drawing the temper on taps to heat very slow, otherwise the edges of the threads may draw too soon and be too soft, which, of course, means a bad job.—By F. W. S.
PLAN 1.
For tempering drills, take a half ounce of sulphate of zinc, three-fourths of an ounce of saltpeter, one-eighth of an ounce of prussiate of potash; pulverized together, used as a mixture into which to dip the drill when heated to a dark cherry red, will prove satisfactory for your purpose. The article should be dipped into the mixture so as to cover all the parts which it is desirable to harden, the same as though melted borax was used. After dipping the drill, return it to the fire, increasing the heat to what is commonly called bright cherry red. Then dip into clear, soft water, into which about half a pint to the gallon of common salt has been dissolved. I have never had experience in dressing drills for quartzite, but good steel hardened in this way will cut glass very readily.—By B. H. B.
PLAN 2.
I will try to describe, for the benefit of many, the way in which I temper small drills. I learned it from experience, and think there is no better plan. I dress the drill to the desired shape, then heat to a cherry red and insert it gently in a cup of warm water, which should be placed on the forge for convenience. I then take it out, and when the temper runs down to a dark straw color, dip it into a can of common lard or grease, such as we use in cutting threads, and cool it off above the cutting edge. This rule is good for chisels, punches and all kinds of small tools. I have tempered drills in this way that would drill through one and one-half inch wrought iron. I think they are less liable to heat than those tempered in water alone.—By J. W. J.
PLAN 3.
My way of tempering drills for chilled plow metal is worth telling.
When the drill is hot I rub in cyanide of potassium, the drill being hot enough to melt it. I then heat it so that it will be a dark cherry red when held in the light, and cool it off in warm, soft water, made with very strong brine. I don’t draw the temper. The drill will look white, but the drug makes it hard and tough. I use the drill dry, and never turn it backward, for if I did the edge would fly.
I have tempered mill picks in the same way, and with good results. I generally make my drills of old files, but good, plain cast-steel is better.—By J. W. J.
PLAN 4.
To temper a drill so that it will drill a hardened saw blade, heat the drill in a charcoal fire to a cherry red, and quench it in spring water, to which is added a handful of salt, then make the drill bright, and draw to a light straw color.—By W. R.
After learning the grade of the steel and what heat it will stand, procure the best drill steel and forge out to shape. Leave it as heavy above the drill point as it can be, and still be clean in the hole after it is drilled. Have your drill tapered or beveled, so that when the heel of the bit is cutting, the point will be through the plate. File up sharp with a very fine file. The cutting edge should be sharp and smooth. If a coarse file is used, it will leave a rough edge that will cut in soft iron well enough and in steel would crumble. Procure a block of lead, heat the drill to a cherry red and drive it into the lead, say half an inch, and then leave it to cool. If the steel is good it will never be too soft, and may sometimes be too hard. If too hard, don’t try to draw the temper, as it will then be too soft on the cutting edge. Temper over, and don’t heat quite so hot, and you will soon learn what heat the steel will require. I have one that has drilled a great many holes and is sharp yet. Never use this drill on iron, as it will fly like glass, and there is as much to keep in mind in using a drill for this work as in tempering it. Always use a hard wood block under the plate to be drilled, and it should be one on which the saw will rest only when it is under the point of the drill. Never force the drill, and use plenty of oil. When the heel of the drill is about through, turn it and feed very cautiously, or you will break your drill or crack your plate if it is thin, and that crack will not be seen until the saw has been run some time.
I have had saws brought to me that had been drilled and had had a piece of brass or copper riveted in the drill hole. They cracked again farther down. Never plug a hole that has been drilled in a saw plate. I have never seen a saw crack below the drill hole if drilled properly. When a saw is cracked it is cracked further than the naked eye can see, so you must get the course of the crack and drill in that course, say one-half of an inch further down. Then your saw will never crack again unless it goes to pieces.—By W. G. R.
Concerning the tempering of drills for drilling saw plates, my advice is to harden the drill and bring it to a straw color. Use turpentine instead of oil, be careful not to give the drill too sharp a point, and you will have a tool that will drill any ordinary saw plate. Even glass may be drilled with it by using a bow-drill.—By D. W. C. H.
Heat the tap in a clear fire to a dark cherry red. Use the blast sparingly, and do not heat too quick, but give the tap time to “soak,” so that it will be thoroughly and evenly heated all through. Now dip it endwise and all over in water till cool. To draw to the proper temperature (a dark straw or purple color), hold the head of the tap in a hot tongs, passing it backward and forward and round about over a clear fire, keeping it covered at the same time with oil, which you can apply by having a small piece of rag tied on the end of a little stick, which you can from time to time dip in the oil as you rub it on the tap. The oil will regulate the temper evenly, and keep the “teeth” of the tap from heating sooner than the body of it. The above is what we might call the straightforward way of doing the job; but in order that someone who is not regularly accustomed to doing such work may not fail, I will give a few hints or suggestions that may not be amiss.
As a precaution against cracking in hardening, it would be well to rub the tap while hot, and just before tempering dip it in a paste made of flour and prussiate of potash, or yeast, to protect the tap from a too sudden cooling. It would be well to have the chill taken off the water before dipping, or, in other words, to not have the water real cold. Remember not to let the tap get too hot; don’t let it get too hot and then cool again before dipping; heat slowly and harden at the lowest heat it will harden at. Keep this in mind, and you need not have any fears that you will spoil the job. Now, after having it hardened, you will proceed to draw the temper. Rub the sides or grooves of the tap with a piece of sandpaper, so that you can see the temper more plainly as it comes. Hold the head of it in a hot tongs and keep the oil applied as I have said above, until you bring to the desired temper. All manner of taps, either large or small, can be hardened and tempered in the way described.—By I. A. C.
Take an old piece of steam pipe, or other iron cylinder, about fifteen or eighteen inches long and large enough to admit of the tongs holding the tap being passed into it. Plug up one end of this pipe solid with some non-combustible substance such as a bit of clay and bung it in the fire with the open end toward you and slightly higher than the closed end. Take care that no bits of coal get down into the pipe. Now grasp the tap by the square end made for the reception of the wrench (in no case must it be held by the threaded end in the tongs), and as you see that the pipe is red hot insert the tap and by turning the tongs keep the tap slowly revolving in the pipe and when it looks as though it were red hot pull it out and thrust it into a nail-keg or some other handy dark corner and see if it is heated all over evenly. This is important. By a little attention you will soon get in the way of noticing the cooler portions by their slightly darker color. Repeat these operations until you are sure you have an even but not a high heat (say a dull red). Then plunge the tap point downward into a bucket of clean soft water and hold it still until it is as cool as the water. With a few times trying we believe you will find this an easy way to harden a tap or other small tools in a common fire without risk of burning or injuring the steel. Now polish the shank and flutes of the tap, and by again inserting it into the hot pipe you can easily let down the temper to any degree of hardness required. In the latter case do not have the pipe too hot, as it will make a better tap to let the temper down slowly and evenly.—Industrial World.
Heat the die in a clean fire to avoid a cherry red heat, not hot enough to scale, for that would open the “grain” of it, and therefore cause it to crack in hardening, or render it more liable to break while using. Cover the die while hot with a little sawdust first, and then cover all with ashes to keep out the air, and let lay until cold. Or another way you can anneal. Put the die or dies in a piece of iron pipe one and a half or two inches in diameter and eight or ten inches long; have one end of the pipe closed up. Now put the pipe in the fire, and while heating put in some little pieces of old leather, or hoof parings, or charcoal, either one will do if you haven’t got the others, or you may put equal parts of all in if you have them. Heat all to a cherry red heat. Plug the pipe up with a piece of iron, and let it lay covered up in some convenient place with ashes until cold. After having them cut the next thing in order will be to temper them. Now, with this operation you must be careful or you will have your whole job spoiled. Heat them in a clean fire to a red heat; just hot enough that they will harden, and no more. As a precaution against cracking you may cover them with prussiate of potash or with a paste made of soap and oil. If you have neither paste nor potash you may throw a little salt in the water you harden in, and if you have not heated them too hot there will be no danger of their cracking. After being hardened rub them on sand or on a grindstone to brighten the sides so that you may see the temper better.
To draw the temper you can heat a piece of iron, hold it in the vise, place the dies on it, and turn them from one side to the other with a little rod until they are brought to a dark straw color.
Try this plan now, and see if you won’t succeed “on a small scale.”—By I. A. C.
PLAN 1.
The best plan of recutting and tempering old dies for cutting threads, when the taps are perfect and the dies are hand-plates, is to cut them by filling the sides between the dies with lead. If they are machine dies, three or four to the set, a tap with a spiral flute is the best. These flutes can be made in the lathe or with a file. A tap of this kind is best for cutting either hand or machine-made dies. To temper them, heat them slowly in a clear fire to a cherry red, or at the slowest heat at which they will harden, cool them in clear water with the chill off, then brighten and draw to a temper at a straw color over a piece of hot iron.—By R. T. K.
PLAN 2.
For recutting and tempering old dies, my advice is to heat the dies a light cherry red, then cover them in air-slacked lime or dry loam till cold. To anneal, place your dies in the plate, put your large tap in the vise, run the dies on the largest part of the tap till the thread in them is sharp, file out the vents, harden at a low heat, rub them with tallow and draw temper till the tallow burns off, and then cool.—By S. N.
When tempering cold chisels or any other steel articles, heat to a very dull red and rub with a piece of hard soap; then finish heating, and harden in clear, cool water. The potash of the soap prevents the oxygen of the atmosphere from uniting with the steel and forming rust or black oxide of iron. The article will need no polishing to enable the colors to be seen. This will be appreciated when tempering taps, dies or very complex forms not easy to polish. Never “upset” a cold chisel. It is sure death to the steel.
PLAN 1.
My way for tempering a butcher’s knife is as follows: I heat it slowly to a cherry red, being careful that the heat is distributed evenly over it. I then dip it in oil with the back downward, and then draw to a dark straw color.—By J. B. H.
PLAN 2.
A good method of tempering butcher knives is to securely fasten the knife to be tempered between two pieces of iron about three-fourths of an inch thick, and a little longer and wider than the knife. Then heat irons and all together until it becomes a bright cherry red; then dip the whole in water. By this method you can harden thin pieces of steel without warping.—By H. G. S.
I have seen in books several good articles on tempering edge tools, but I have not observed any directions for straightening knife blades, etc., after they have been immersed in water and without changing the color.
After the immersion in water an edged tool is apt to spring. It should first be brightened with sandpaper or by being rubbed on a brick. Then the convex side must be laid on a bar of hot iron, and while one end is held by the tongs the other should be pressed on with something that will straighten it. The blade need not remain on the iron long enough to change color. The temper can be drawn on the hot iron until the right point is attained.—By W. J. R.
PLAN 1.
To harden thin blades without warping them out of shape, be very careful about heating. Heat in the blaze, evenly all over, and then plunge perpendicularly into a tank of raw linseed oil. Be particular to plunge into the oil perpendicularly, and draw the temper on a hot iron. Another way is to heat and harden the blades between two straight pieces of iron.—By D. D.
PLAN 2.
To get the temper of knife blades uniform requires skill on the part of the workman. The nearer all parts of the blade are heated and cooled alike the more uniform will be the temper. They are generally cooled in oil, to harden them. This method does not give as good results as when water is used, but reduces the liability of cracking and warping. The temper is drawn in various ways, on sand, and in revolving ovens, and in hot animal oil. In the first method the degree of temper is regulated by the color; in the second, by color and degrees of heat, and in the last, by degrees of heat, which is found by a pyrometer or thermometer, and sometimes by some substance which will melt at any known degree of heat. There has, as yet, no way been found to harden knife blades and get a good cutting edge, without warping them out of shape.—By W. B. & Co.
PLAN 1.
Perhaps some reader has mill picks to temper, and has no good recipe for tempering them. When sharp and ready to temper, get a pail of rain water and a bar of common, cheap yellow soap. Heat the pick to a cherry red, and cool it by sticking it in the soap. Cool it until the soap gives it a white coating. Do this three times in succession. Then heat it the fourth time to the same color and plunge it in the rain water. Don’t draw the temper.
I don’t know what property the soap contains that is of benefit to steel in this way; but if anyone will give this a careful trial, he will use no other means for tempering mill picks.—By J. A. RODMAN.
PLAN 2.
Being both a miller and a blacksmith, I have had considerable experience in tempering mill-pick work, and believe that I have at last found out the best way of doing it. In the first place, you employ a good quality of steel; secondly, the steel must be very carefully worked, using charcoal only, as stove coal would destroy the carbon in the steel, and thereby render it brittle. Never heat the steel above a red heat, and after the picks are made, water-hammer the ends well, and let them cool off. Have in readiness an iron vessel containing mercury (three inches deep), and place this vessel in a bath of ice water, to keep the mercury as near the temperature of the water as possible. Now heat three-fourths of an inch of the points just to a color, and set them straight down into the mercury. Let them cool there, and do no drawing.—By W. P.
PLAN 3.
Take three gallons of water, and of ammonia, white vitriol, sal ammoniac, spirits of nitre and alum three ounces each, six ounces of salt and two handfuls of horse-hoof parings. When this mixture is not in use keep it in a jar and tightly corked. Heat the pick to a dark cherry red and cool it in the liquid just described. Draw no temper.—By H. M.
PLAN 4.
For tempering mill picks, I take six quarts of salt water, one ounce of pulverized corrosive sublimate, three handfuls of salt, one ounce of sal-ammoniac. Mix, and when dissolved it is ready for use. Heat the picks to only a cherry red, plunge in the fluid just described, but do not draw to any temper. In working them be very careful not to heat them; work with as low a heat as possible. In drawing, there ought to be a good deal of light water-hammering. In heating picks I find charcoal much better than blacksmiths’ coal, because the former does not heat so quickly, and so there is less danger of overheating.—By G. V.
PLAN 5.
My recipe for tempering mill picks is one I obtained from an English miller, who had used it for thirty years, and would try no other. It is as follows: Salt, half a teacup; saltpeter, half an ounce; pulverized alum, one teaspoonful; soft water, one gallon. Do not heat above a cherry red, nor draw to temper. —By I. L. C.
PLAN 6.
To dress a mill pick, it is necessary to have a smooth anvil and a hammer with its face slightly rounded and very smooth. Great care must be taken in heating, for too high a heat will spoil the whole job. What hammering the edges will require should be done at first before the steel is thinned any, because blows delivered on the edge of hard steel crush the steel more or less, according to the number and weight of the blows. The body of the steel is partially separated and very much weakened, although it will not show any flaw when fractured.—By H. BUCK.
PLAN 7.
I use pure rain water in tempering mill picks, and get better results than I can with any composition I have ever tried. I draw down thin and even, leaving no light or heavy places in them, and in the last heat I wet-hammer with a light hammer. I hammer as much on one side as on the other. I heat very slowly to a dark cherry, and immerse in water that is about the temperature of the air. I am very careful as to how I immerse the picks. If it is done too quickly, circular cracks will form around the edge, and if too slowly, cracks will appear straight in and back of the edge. I heat them only as far up as I wish to temper, and then cool them off all over. I then rub them bright and hold them over the fire until they are warm—not warm enough to change the color, but sufficiently to make them tough.—By W. J. R.
“The best mill pick man he ever knew always withdrew the steel from the water before its temperature was reduced to that of the water, leaving enough heat remaining in the steel to dry off the water in about two seconds.” This I believe to be one of the secrets of expert hardening, and I have somewhere read that steel treated thus will bend, providing that the bending be done while the steel is still warm, but that the bending cannot be proceeded with after the steel has once got cold after hardening it. It has been stated that the file-makers utilize this fact by drawing the files from the water when at about eighty to a hundred degrees, and pouring cold water upon the outside of the curve of warped files, so as to contract the same, and therefore help to straighten the files.—By T. H.
Having had fifteen years’ experience in axe work, I will, for the benefit of the inexperienced, give my way of tempering.
Some seem to suppose that with an edge tool everything depends upon the temper. This is a great mistake. While tempering is a very essential part, it is no more so than is the forging. Unless the steel is properly worked and refined with the hammer, there is no temper in the world that will give a nice, smooth cutting-edge. With a thick axe almost any temper will stand. If too hard it is too thick to break, if too soft it is not likely to bend. But when an axe is made thin, as it should be to cut easy, no haphazard way of tempering is going to answer the purpose.
The right temper is in a thin axe a very essential point, and can be obtained only with the greatest care. In making over an axe, after the finishing touches have been given to the steel, I grind out the hammer marks before tempering, as this can be done much easier before than after, and the temper can more readily be seen. Having a good charcoal fire I put in the axe with the bit towards me, watching closely the extreme edge to make sure that the steel does not get too hot. If it is overheated the fine grain of the steel is injured, and cannot be restored. I am careful to keep dead coals against the edge until the axe is of a bright red to within about half an inch of the edge. I then take a firm grip upon the head with the tongs and put the bit into the coals, moving it round, and turning it over (without any blast) until a perfectly even heat is obtained. When at a bright cherry heat I plunge it at once into a tub of brine to within half an inch of the eye, and move it slowly about until the steel is cold.
If properly hardened when taken from the brine, the steel will be a grayish white. After wiping, I brighten up the bit by rubbing it with a piece of grindstone, also by scouring it in sand. I then proceed to draw the temper, the most important part of all. Some set the axe upon the head in the fire and let the temper run down as they would with a drill or cold chisel. But this is a bad way, and those who follow it are fifty years behind the times. Axes tempered in this way will grow soft after grinding a few times, as everyone must see. Besides, this method of drawing the temper is attended with many difficulties. My way is to level down the fire, seeing that there is no blaze; I then set a brick up edgewise each side of the fire, and lay across a one-fourth inch wire upon which to rest the bit; I place another brick in front for the head to rest on, and lay the axe down flat over the fire. The axe should be from four to six inches above the coals, according to the amount of heat.
The temper should be drawn slowly, in not less time than five minutes, and ten or fifteen minutes would be better. As to the color that marks the point to which the temper should be drawn, I know nothing reliable, for in making over old axes we find different grades of steel. I sometimes leave the temper at a dark straw color, at others at a deep blue. Were I to be governed solely by the color, I would prefer a mixture of copper color and blue. But the smith who in making over axes relies exclusively upon the color in drawing the temper must expect to meet with many a failure. The only sure and reliable way is to use a nicking tool.
I use the pene of a small hammer for that purpose. When the temper is at a dark straw color, I take the axe from the fire and tap it lightly upon the edge. If the pieces fly I pronounce it too hard, and put it back and draw it lower, then try it again, and continue to do so at short intervals, until the sharp ring of the steel dies away, and pieces no longer fly off, but turn over, and readily fly when tapped the other way. When this point is reached, I plunge it in water or lay it aside to cool.
Before cooling, it would be a good idea for a new beginner to put the axe in the vise and try the edge with a rasp. He will soon learn in this way when the right temper is attained. If the steel yields to the rasp the temper is too low. The axe should be kept the same side up in drawing the temper. I prefer brine to water for tempering. To one-half barrel of water I add some four quarts of salt. The “chill’ should be taken off in Winter, or the tool is liable to crack in cooling.
Now, one word about grinding, as there is not one man in ten that knows how an axe should be ground, to stand. In the finishing process the stone should run towards the grinder, and the axe be kept in constant motion, lest it be ground too thin upon the edge for Winter use.—By W. H. BALL.
For the benefit of those blacksmiths who are without any good method for tempering a large chopping axe, I would say: Get ten or twelve quarts of soft rain water. Put the same in a clean pail or tub. To this add one pint of common salt, letting the salt dissolve before the mixture is used. Heat a piece of iron and plunge it in the water. This is done simply to take the chill from the water. Now heat the axe over a slow fire to a dark red-hot. Place about three inches of the axe in the water, and, while holding it in this position, keep moving about, that is, do not hold it constantly in one place. After it has cooled to the depth mentioned, take it out and rub the cooled part on a brick or stone, so as to enable you to see the temper draw toward the point. When it is down to a dark blue at the keen edge, plunge it deep into the water, and after it has cooled off it is ready for use. One great trouble with smiths when tempering edged tools is that they take the heat on the end or edge to be tempered too short, and, at the same time, they get the tool hotter at the points than it is back of them. The main thing to be remembered in tempering is to heat the steel to a uniform and even degree throughout, and to get as long a temper on the piece to be tempered as it is possible to get. A large tool with only one-fourth to three-fourths of an inch of temper will break, nine chances out of ten.
To illustrate what I mean by a short temper, I will relate a few instances of tempering that came to my notice a short time since. A certain smith had sharpened and tempered a screw-driver and cold chisel from four to six times, and still both would break. After he had experimented to the extent of his patience, failing to get either tool to stand satisfactorily, he came to me and complained that the steel was not good. I asked him if he had not overheated it. He thought not. So, after satisfying myself, I sharpened both for him at his own fire. In tempering the screw-driver, I cooled the point up to about one inch, and let it run down to what I thought was the proper temper, which was a dark blue. His helper has since used the tool on about one gross of screws, and it is as good yet as when first sharpened. I also gave the cold chisel about one inch temper, and it has not broken since the trouble the owner had with it. The difficulty in this case was that both tools had been cooled only about one-fourth of an inch back of the point, which gave the short temper. The result was as described. I explained these points to the owner of the tools, who admitted their correctness after being convinced by seeing my experiments.—By H. R. H.
PLAN 1.
To temper axes heat the poll in a charcoal fire to a little more than a cherry red, then change ends and heat the bit in the blaze to a cherry red all over. Be sure to heat it all over. When hot enough cool the bit only, in a salt water bath. Plunge it in the water at once; if you don’t, there may be a fire crack that will spoil it. If done right the steel will look like silver. Scour with a brick and put the poll in the fire endways. Use no blast and let the temper run to a blue. Then you will have an axe that will cut.—By H. A. S.
PLAN 2.
My way of tempering axes is as follows: I split the iron poll to receive the steel, heat the axe bit up to the eye to a peculiar red heat, plunge into salt brine and fresh water until it is cold, and then draw to brown yellow over a charcoal fire. —By C. K. H.
PLAN 3.
To have a good axe steel must be worked at a low heat and hammered all over even before heating to harden. If there is no grindstone hammer, and file to an edge. Brine is the best fluid to harden in, but fresh water will do. In hardening, the axe should be given a little swing, letting one corner strike the water first. Then brighten the steel and let the temper run down to a shade below a dark blue.—By J. W. C.
PLAN 4.
My way of tempering a chopping axe, that I have tried for the past four years and which has always proven successful, is as follows: Take six pounds of tallow and two pounds of beeswax, and one ounce of finely pulverized sal ammoniac. Melt the tallow and beeswax together, and then put in the sal ammoniac. Pour the mixture into a sheet-iron box, which, for convenience, should be two feet long, four inches wide and four inches deep. A box of these dimensions will hold enough of the mixture for tempering any sized axe, hoe or other tool. When the axe is ready for tempering, heat to a white red; then put it into the mixture deep enough to cover the steel all over. Let it remain from one to two minutes, then put in the water the same way. Then draw to a blue color and return to the mixture as before. Then hold it over the fire until it becomes dry, and then put it back in the water to cool. Never heat the steel more than to a light red when forged out.—By T. G.
PLAN 5.
To temper axes I heat the edge to a bright red, then, when it is all ready to temper, I use the following composition: Three gallons of soft water; two ounces of prussiate of potash; quarter pound of saltpeter and one pound of whale oil.
This should be kept in a small barrel and stirred well just before using. I then heat the axe to a cherry color, and very even, and then draw to a purple, and I have an axe as good as a new one.
But another point must be kept in mind, and it is this: All axes are not of the same steel. By hammering you can tell whether the steel is hard or not. If it is soft do not let the temper come down so low as when it is hard.—By B. T. C.
PLAN 6.
I have had over fifty years’ experience in work of this kind. I am now seventy-two years of age. I will venture to explain my way of tempering a chopping axe for the benefit of tool makers and blacksmiths. It is my custom to make axes very thin. I would heat the axe over a fire in the blaze until it is heated through even and to a moderate cherry red. I would then dip it into a solution of salt and water nearly to the eye. As soon as it is hardened, and as quickly as possible, I would put it over the blaze again, until there is no danger of cracking. I would then rub it off clean, and let the temper run down. In the first place, it will look as if the tempering is done. The workman should not be deceived by that. If he waits a little he will see a brass or copper color coming down again. Let this come down to the edge, and then to a light pigeon blue. When this stage is reached, cool the eye of the axe, so that it will not run any lower. Finally, hang the axe up until it has cooled off sufficiently for handling.—By A. H.
PLAN 7.
My method is to temper in beef tallow. After drawing out I heat the axe to a medium bright cherry red, have a kettle of tallow ready and dip it in the same as if in water; I let it remain till the blaze has nearly left the tallow, then take the axe out, brush off the grease, lay the axe on the fire and draw the temper to a deep blue. I have some rifle powder ready, and often sprinkling a little on the edge, let the temper run down till the powder flashes, and then cool in water. If the steel is hard I let the powder flash the second time. I draw out from ten to twenty-five axes every year, and hardly ever miss if the steel is good. I have followed this plan successfully for over fifteen years. —By J. L. R.
To those who wish the best method of tempering hand hammers, I would say that it is impossible to get the center of a hammer face too hard. Of course we cannot harden the center without hardening the outside, and if we permit the hammer to remain in this condition the edges will chip off. To avoid this we must temper the outer portions, giving it either a straw color, copper color or blue, according to the work which we propose to do with the hammer. To draw an even temper, make a collar of bar iron, the thicker the better for the purpose, just large enough to slip over the hammer. After it is finished, polish the sides of the hammer so that when it is slipped in to the collar the temper will be drawn quickly. Of course the face of the hammer must also be smoothed off, so that the colors can be distinguished easily. Now heat the collar to a white heat and slip it quickly over the hammer. When the proper color is seen on the outer edges, slip off the collar and cool your hammer at once in whatever liquid you have on hand for that purpose. Care must be taken that the center of the hammer is not also heated so as to destroy the original hardness. If a hammer is tempered all over, so that the edges will not chip, it will be too soft in the center and the face will sink in at that point after use.—By M. EHRGOTT.
My method of tempering hand hammers is this: Put one quart of water in a small can that will hold the hammer also. Heat the hammer all over, evenly, to a bright red. If you wish to temper both face and pene, put a punch in the eye and let the face down in the water as far as you wish the temper to extend. Hold the hammer so about half a minute, then turn it over and treat the pene in the same way. Change back and forth from face to pene until the center is black, then slip the hammer off the punch into the can, and let it stay until cold. I make all my own hammers, and they never crack or break in the eye.—By J. N. B.
My way is to first heat the hammer to a cherry red, and then dip it in clear water. In drawing the temper, I use a fine, sharp file for testing it, judging in this way when it is drawn enough. —By J. B. H.
Tempering a hammer is a job which a great many men cannot do as it should be done. I was that way myself until one Winter, when, while traveling in Iowa, I learned from the foreman of a shop there the following method of tempering: After the hammer has been dressed in good shape and everything ready to temper, get an old coffee pot, or some vessel with a small spout attached; heat your hammer to an ordinary heat, and holding it over the slack tub, pour water from the coffee-pot spout into the center of the face until cold. This hardens the center to a greater depth than it can be hardened by plunging the whole face of the hammer into the tub in the ordinary way. The temper can afterwards be drawn on the edges.—By S. E. H.