On Jul 25, 4:53*pm, Tim Wescott wrote:
I'm going to make a wire-bending fixture for putting fairly small-radius
bends into 1/8" music wire*. *I have some 1/8" oil hardening drill rod
and a slightly undersized 1/8" reamer designed for installing dowel pins
in tooling. *I also have some 1-1/4" round bar, made of mystery steel but
there's a good chance that it'll harden at least a bit if encouraged.

So I'm planning on putting a couple of pins made out of the drill rod
into the end of a bar, and bending the music wire around the pins. *I'm
_assuming_ that if I don't harden the drill rod that it'll bend, although
I'm in a hurry so I'm going to test that assumption by trying to use the
tool.

After I bend up my first attempt at a fixture I'll want to do it up
right. *It seems like I should just be able to heat up my whole assembly
to a dull red then chuck the thing into a bucket of water -- does this
sound correct? *I have some pottery clay lying around so I'll probably
paint the pins with clay & charcoal in an attempt to protect them from
decarburization. *When I fish it out of the bucket should I try tempering
it? *If so, how, and how much?

The heat-generating tools I have available are pretty much a propane
torch and an O-A cutting torch. *The temperature measurement tools I have
are my own somewhat color blind eyes.

* Music wire is moderately high carbon -- 0.7 to 0.9%, and drawn in a way
that work-hardens it nicely. *It's soft enough that you can cut it with
diagonal cutters successfully, but hard enough that you'd better hide the
cutters from their rightful owner when you're done.

--http://www.wescottdesign.com

Oil-hardening means just that, OIL-hardening. If you use water, it's
going to crack or be brittle. Even old crankcase oil will work.

Piano wire can be cut with piano-wire nippers, I've got a nice set of
Starretts I've inherited. Or just use the ever-popular Dremel cut-off
wheels. I also inherited a number of sets of dikes that had been used
on music wire, they'll never be any good for cutting electrical wire
again...

If you want properly hardened pins, just go get some dowel pins
instead of monkeying around with drill rod. They'll be properly
ground and polished, too. MSC and most of the other industrial
suppliers will have them.

Have you looked up minimum bending radius for that size of wire?
Looks a little sharp to me. I found out long ago that trying to get
too sharp a bend in the stuff just leaves you with two pieces, either
while bending or shortly after putting the part to work. Annealing it
just leaves you with a weak spot and eventually, the two pieces.

There are a number of music wire bending jigs out there that the RC
guys use for landing gear and pushrods, might be a look at those would
be in order.

Stan