Hardening Steel:
How you harden steel depends on what kind of steel you have. If you want to harden the steel yourself then you would probably want to use o-1. O-1 is an oil hardening steel. Don't use any oil use something like this (
http://library.cbest.chevron.com/lub...5?OpenDocument)
Some oils have low flash points and can bust into flames, or explode. But if you have the right oil then you heat the steel up with a torch until it starts to turn red. The brighter the red/orange the harder the steel will become. Once you have it heated then you quickly dunk it into the oil and quench it. It's a cheap and dirty way to do it. Remember usually the harder you make the steel the more brittle it will become.
I would suggest picking up a Machinery's handbook. It has a lot of useful information in it.