Originally Posted by
Scott Gibbons
...and I would like to use case hardened fasterns, but I would like to do the case hardening myself.
Why?
.
Often times I will like to do these kinds of things too, just for the sake of being able to do them and learning something new... but, case hardening screws, unless you plan on doing some machining to them first, I see no point. Especially when you can buy a handful for a few bucks at the hardware store.
.
First off, stainless and zinc are the wrong types of steel to try to harden... you need a specific kind of tool steel with a percentage of carbon, some case-hardening compound, a way to heat them evenly and many of these steels will harden with air cooling others will require oil or water quenching - it all depends on the hardness you want in the end.
.
It's not quite as easy as it sounds, when you consider manufactures have trouble getting things heat-treated perfectly in large ovens designed for that purpose. I've looked into it and aside from doing some hardening of custom ground tool tips have pretty much decided it wasn't worth the effort.