a torch. I still have those chisels. they are hard; not brittle, tough
as a proverbial nail.

dave

Juergen Hannappel wrote:

Bay Area Dave writes:


wouldn't they be discolored? I use to harden chisels for automotive


Not necessarily, softening starts well before coloring (depending on
the steel type, of course).


use. Worked great; heat 'em and quench 'em in oil.


But makes then brittle, you should temper them after that, there are
lots of web sites that tell you how. What do you use to heat them up?