Brian Ross
rossoon@imag.net
I have also used 3/8" sockets(Torx and various security fasteners)for
patterning, held in a similar ad hoc fixture. Of course, you don't have to leave the pattern end as they came from the box. Which is why garage sale stuff is great.
I have a brass tsuba which I have been cold forging using one of these found tools. I will try to remember to take a picture to post.
Brian Ross