I routinely heat small items for hardening with a "propane" torch. I
do use a couple of firebricks to make a 2 brick forge. I know it is
hot enough when it will not attract a rare earth magnet. I have heard
that MAPP gas with a propane burner is not as hot as propane .. I
suspect that is so ... make sure you have the right attachment to your
MAPP. What is a small item: up to 1/4 X 2 X 2 easily that would be
wood planer blades and chisels. Drill Rod 1/2 X 2 inches also.
You'll know it works when after quinching it is glass hard, won't cut
with a file. Temper is a 250 degree oven for 1/2 to 1 hour.
Directions on my O1 steel packaging.
--- In 7x12minilathe@..., <gregorstransky@...> wrote:
Another question from a beginner. According to a basic book about
home
machinery it is possible to temper metal using a MAPP gas torch. I
have
tried this on a 4x1/2 punch made out of annealed 4140 with a
standard MAPP
gas torch suitable for plumbing work. I was unsuccessful because the
punch
did not get hot enough. Any suggestions? Thank you.
Gregor Stransky, San Antonio, Texas
