Hi all,

At a recent watchmaker's fair I bought a small vice. Old, in bad shape, but
better than anything I've got at the moment. The thing actually cracked in
half somewhere in its lifetime and was welded back together by someone with
a very big welding machine. The problem was that the jaws were not parallel
properly after that; there was a .7 mm gap on one side.

I've annealed the jaws and filed and sanded them back into shape. They close
well now, and are beautifully straight, smooth and polished, just as I
wanted.

My question: how can I best re-harden them? The jaws are only 6 cm wide, but
I'm only used to working with tiny pieces of steel to make watch components
or small tools. Can I just heat to cherry red and quench in oil? And then
temper by re-polishing and heating to some colour (blue, for example)?

I only have a torch, no kiln or something like that.

Cheers!

Rob