October 24, 2006

Making tools to make hammers

A few weeks back, my blacksmith friend Tim mentioned that we should get together and make some handled tools - hammers, handled punches, fullers, etc. So last weekend, I went over to his shop, and we made a slitter and two hammer eye drifts. I brought some axles, leaf and coil springs and we picked an old 1 x 7/8 inch fixed axle to draw down for our drifts. We made them about 16 inches long, with the widest part at about 12 inches. We took turns on the 16 pound (7.25 kg) sledge hammer, and really moved the metal! We tried to keep our pieces straight as we forged, by doing some correcting blows, but there were still a few twists near the small end. Tim cleaned up one of the drifts with a flap sanding disk, and it looked beautiful. It needed a small amount of cleanup on the edges, but the overall shape was exactly what I was aiming for. We also straightened out a few coil springs using a bending fork mounted on a 4x4 inch piece of tubing set into a concrete pad with a 3 prong socket. The pair of heavy tongs that I had made came in very handy. Tim put a piece of square metal tubing over one end of the spring, and I held the other end with tongs, and we maneuvered the spring over to the bending forks. Then he would bend and I would position the spring for the next bend. After this, we ran out of time. At our next work session, we will smooth and straighten out the drifts, and hopefully make a few handled slitters or other small tools from our stash of car axle material. I think the axles and coil springs are 4140 material, but I am quite sure that they are steel!

Regarding the 16 pound sledge hammer, we didn't do the circular overhead swing, but rather a more controllable (and more tiring) swing where we lifted the head to eye level and then pushed or dropped it down. This was partly because I am not used to working with such a heavy hammer, and also because his anvil was only about 125 pound As I understand it, the recommended hammer to anvil ratio is between 1:15 and 1:25. With a 125 pound anvil, this works out to an eight pound (4 kg) hammer at most. Also, the anvil was mounted to a tree stump, and was 8 inches higher than I would like for sledge work.

I am sorry that I don't have pictures, but I will try to make up for it next time.

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