On Wed, 30 Jul 2008 12:02:41 -0700, "Bob La Londe"
wrote:

"Lloyd E. Sponenburgh" lloydspinsidemindspring.com wrote in message


OTOH, if you're VERY careful, use heat-sinks around the area, and use a
tiny pencil flame, you can partially anneal just the sections of the
drill rod that require bending, and leave the working length full-hard.

I like that idea. I just ordered some 17-7 .093 wire to play with for this.
Its a little heavy, but the commercial beam I have uses wire this thick.
Actually closer to .098. The hooks on my home made beams are only .079. If
I can't handle the thicker wire I may search for some a little smaller.

Would you oil quench it when finished for moderately quick cooling and
hardening?

17-7 is a precipitation hardening alloy - forget everything you know
about annealing and heat treating simple steels. The heat treat is
dead easy if you've got a furnace, but you're not going to be able to
do much for 17-7 with a torch.

Personally, I'd get hold of some 302 spring wire and put the effort
into figuring out how to make the forms you need with that. 302 and
the other austenitic stainless steels (304 and 316 are the most
common) are hardened by cold working, not heat treating. If you anneal
them the only way to get the strength back is by more cold work.

You should be able to bend 302, 304, or 316 into the shapes you need
with little fear of cracking. The austenitic stainless steels have
very high elongation properties, i.e., they'll yield and stretch
without breaking.

--
Ned Simmons