Generally if you heat steel sufficiently then let it cool slowly, you may actually be softening it. If on the other hand you heat then quench without calculation, the steel may harden so much it fractures immediately.
There is also case-hardening, which I used to do for pauldrons, plastrons and carapaces. You heat the metal to cherry red then pour prussiate of potash over it. Repeat until you pas out. This forms an obscenely hard (if obscenely-discolored) surface. I was younger then, and reckless. A modern DIY case-hardening compound is Kasenit, but I dunno if this is available locally.
Trust me on this, as I've BTDT...
This is something you want to leave to pro's.
The sheet-metal items I case hardened could stand minor deformation in the course of heating repeatedly. Something as finely machined as a slide, I would never touch. I'd risk deformation, and then I'd have to machine the whole piece again, except it's now hard as a dwarf's nuts!
Just have it hard-chromed
Probably the safest route to a quick (if minor) surface-hardening.
Last edited by horge; 08-13-2004 at 02:57..