Simple Exercises in Blacksmithing
by James M. Drew
excerpted from “Blacksmithing,” 1935
Assuming that the beginner has the necessary tools and equipment, and that he has a fire properly built in the forge, he is ready to begin actual work. The best plan is to start with simple things and to lead by gradual steps to the more difficult jobs that require more practice and experience.
A Fire Poker
As a first exercise, the poker, which has been mentioned as one of the necessary tools, furnishes a good example. It brings into use the three processes of heating, bending and flattening. About 2 feet of round 1/2 inch iron should be used. About 4 inches of one end should be heated to a light yellow heat and bent into the shape of a round eye. At his first trial the beginner will have trouble in trying to make the eye round instead of oval unless he has been told that in starting the bend he should make a right angle bend between the shank of the poker and the part that is to be the eye; then bend the extreme end before closing up the circle. If the middle of the hot part is bent first, as a beginner is likely to do, there is left no handy way to make the bends in the end and next the shank, and an oval instead of a round eye results. After the eye end has been finished and cooled, the opposite end of the rod is heated and flattened out until it is about ¾ of an inch wide, then curved slightly as shown at A in Figure 1.
If a longer handle to the poker is preferred, it is an easy matter to form an oblong eye instead of a round one, as shown at B in the cut, but in this case it will be necessary to start with a rod about 6 inches longer than the one first described.
Hook and Staple
Another simple exercise in blacksmithing is the forging of a hook for a gate or a barn door, and the staple with which to fasten it in place. This exercise involves drawing, squaring, rounding, pointing, turning a round eye, and twisting.
For an ordinary barn door hook, a piece of 3/8 inch round iron is a convenient size to use. One end should be heated to a light yellow and drawn out square so that the corners come out sharp. The end of this square part should next be heated and about 5/8 inch of it drawn down to half the size of the square part, then made round by hammering down the corners. In starting to draw out this last part, the iron should be held over the edge of the anvil as shown at A in Figure 2, so that when struck a flat blow by the hammer, the edge of the anvil will form a decided shoulder between the large square part and the part that is being drawn smaller. The small end is next to be made round and turned to form a round eye. To do this, it is best to start by bending at a right angle from the main part, as shown at B, then bending the extreme end as much as it needs to be bent in the finished eye (C). It is then a simple matter to close the ring so as to form a perfect circle as shown at D. The hook is now to be cut from the original bar at a point that will make it the right length when the point is drawn out to form the hook end. This end should first be drawn out square, then rounded as shown at E, and the hook formed in the end as shown at F.
The twist shown at F is put in the middle of the hook by first heating to a yellow heat, then grasping with two pairs of tongs and turning through one complete revolution, so that the eye and the hook end are in the same relative position as before.
To make a staple for a hook of the size mentioned above requires a piece of ¼ inch iron. One end should be drawn out and rounded, then bent as shown at A and B in Figure 3. It should then be cut off at a point which will make the second leg the right length after it is drawn to a point. A pair of chain tongs should be used to hold the piece while the second leg is being drawn out as shown at C. The bend is completed by grasping the middle of the bent part with the chain tongs, as at D, and holding it over the horn or the rounded corner of the anvil, regulating the bend with light blows of the hammer.
One of the jobs which the farm smith will often be called upon to do is to mend broken chains. The right way to do the job of mending, if time will permit, is to make a new link with which to join the broken parts. For temporary repairs there should be a supply of what are called cold-shut links which may be substituted for broken links without any loss of time. To make a new link, take a piece of round rod of the same size as that used in making the chain, and bend it into the form of a capital letter U as shown at A in Figure 4; then, holding the bent part with a pair of chain tongs, heat the two ends to a yellow heat and scarf the inside corner of each end by holding it at an angle on the edge of the anvil. Notice in B and C that only the corners are flattened, not the whole end. The ends are then bent so that the scarfed surfaces fit together as at D, and the joint is ready for welding. The heating for welding should be done in a clean fire and the link should be closely watched to see that one side does not heat faster than the other. It is a good plan to turn it over often, for the lower side is likely to become hot sooner than the upper. When the end to be welded is perfectly white, and the surface is in a fluid condition, it should be quickly placed on the anvil and struck two quick, light blows: one on each side of the weld. The part at the weld should now be worked as nearly round as possible over the horn of the anvil. This will probably widen the link too much at one end, so that it will look more or less like E in the illustration. To shape it properly so it will resemble the link shown at F, it should be held as shown at E and struck where the small arrow is pointing. This will put the bend where it should be, in the end of the link. If it had been held with its side on the anvil and had been struck on the other side, as almost all beginners do in their first attempt, it would resemble the crooked link shown at G.
Cold Shut Links
There are two good ways of making cold shut links to use as temporary repairs in log chains. In the one shown at A in Figure 5, a piece of rod the size of the iron in the chain is slightly upset at one end and a hole punched in it large enough to fit the other end of the rod which is bent around as shown. In use, this link takes the place of the broken link and is closed together and the end riveted.
Another temporary link which is not quite so strong as the one just described, but which can be made in a little less time, is made by drawing out the two ends of a letter U and bending them around as shown at B in Figure 5. When this is hooked into the place of a broken link, a blow of the hammer will close it so it will answer very well as a temporary substitute for a link.
Hooks for log chains are of two kinds: round hooks large enough for the chain to slide through easily, and grab hooks made narrow with just enough room between the two sides to admit a link edgewise.
There are two common ways of making a chain hook. Where good, tough iron or mild steel of the proper size is at hand, the easiest way to make a hook is to upset the bar where the middle of the hook is to be and the end where the hole is to be punched, as shown at A and B in Figure 6. The hole is then punched, and the iron around the hole is worked as nearly round as possible over the horn of the anvil. The bar is then cut off at the point indicated by the dotted lines, and the end is drawn out and rounded as in B. The hook is next to he bent and beveled so as to have a cross section through the largest part like that shown at C. It should be bent only about halfway at first as the beveling of the back causes it to bend more. The reason for beveling a hook is that it makes it stronger in the line of pull than it would be if left round. The most common weakness in a log chain is the hook which is not strong enough to stand a heavy pull without straightening.
Another way to make a chain hook is shown in Figure 7. By this method iron of smaller size may be used than in the hook just described, for the reason that the iron is doubled at the place where the strongest part of the hook is to be. In forging a hook by this method a part of the rod, marked A, is drawn down to the proper size to form the eye of the hook; then the end of the rod is doubled back and welded as shown at B. The rod is then cut off and the hook shaped as in the case above described; or, if it is to be a grab hook, it should be bent on the corner as shown at C. The novice may have trouble in making the iron bend on the corner; but if he will start the bend by putting the end in the square hole of the anvil, then cool the end while the balance of the piece is left hot, then put the cool end in the vise, he will have no trouble in finishing the bend.
Log chains are often broken because of becoming twisted. This is especially true in logging work. To avoid twisting, every log chain should have a swivel at about its middle point. Making a swivel is a good exercise in forging. To make a swivel it is necessary first to have a mandrel over which to form the middle part of the swivel. For the mandrel it is best to use a piece of 7/8 inch round, mild steel. One end of this should be heated and a very short piece of the end, about ½ inch, should be drawn out to about ½ inch in size as shown at A in Figure 8.
The material for the main part of the swivel should be a piece of mild steel 1 inch wide and ½ inch thick. One end of the bar should be drawn out to 3/8 inch in size and 3 inches long; the middle section about 1 inch long, should be left the original size; and the other end also drawn out to 3/8 inch the same as the first part, as shown at B. A ½ inch hole is to be punched through the middle section, and the piece heated to a white heat and placed on the mandrel to be worked into the shape shown at C.
The eye is made by welding the end of a 7/16 inch rod back on itself to form the opening, then working the shank down to ½ inch as shown at D. The shank should be just long enough to go through the main part of the swivel, through a washer, E, with enough space to make a good head when riveted. The riveting should be done while the end of the shank is red hot. The two arms of the swivel should then be bent together and welded in the same manner as the chain link described previously. The completed swivel is shown at F.
Riveting the shank in place will probably make it so tight that it will not turn easily. The cure for this condition is to heat the whole swivel to a light red heat and turn the shank around a few times while hot.