I posted this 100 year old tool just prior to our old site going T.U. About a month later, I was watching one of my favorite programs, Roy Underhill, and the woodwright shop, on pbs. He had a blacksmith guest making some gate hinges, and used this same model tool for threading. What he said, and I did not know, was this type of die did allot more swaging of the threads, than cutting them. Also, the tap that was used with it, was a tapered one, so the size of the threads coud be matched up for fit. I thought this was quite interesting, and news to me. If you google the woodwright, you can watch how it was used, in the gate hing project program on your computer.
Wayne