I went to the Habitat Restore today and picked up some good stuff. 3 Craftsman sockets, 4 Craftsman wrenches, a Briggs & Stratton complete tune up kit for old B&S points type engines and 3 odd taps. The taps are tapered their whole length not just at the bottom to start them like a normal tap.. They are not pipe taps. The sizes are, 3/4-10, 5/8-12 and 1/2-14. I believe they may have something to do with a blacksmith. They each have a different size square drive. I am sorry I can't do pictures. These are a course thread.

EvilDr235

I believe they may be "boiler taps" or "hot taps".  Just a WAG.

I have not found any pictures of the taps, but they do sound like boiler taps after reading about them. When I first spotted them I thought they might be Acme taps until I got a closer look.

EvilDr235