can you get prehardened stainless too hot?

SkaerE · Mar 16, 2003

while profiling/grinding?

i read that some stainless steels will air harden at relativly low temps, how hot are we talking about?

thanks

Chuck Gedraitis Knives · Mar 16, 2003

I have used the rule that if your grinding and your fingers start to burn then it's too hot. Straw colar is around 400deg. Blue and purple is between 600-700deg. Some air hardening steels will harden while your trying to drill a hole in it. Just keep it cool enough to hold.

Epsilon · Mar 16, 2003

i read that some stainless steels will air harden at relativly low temps, how hot are we talking about?

1350-1400°F. This is a broad range in which austenite begins to form in many knife-worthy steels. That, (austenite) being necessary first to start getting steel hard upon a subsequent quench. Hope that helps.

SkaerE · Mar 16, 2003

ok, so pre-heat treat i can really hog out the metal for profiling and be generally ok right? (as long as it doenst reach 1350 or so)

tom mayo · Mar 16, 2003

pre heat treat you can pretty much get it as hot as your little grinder can get it without a worry..........after h/t it is an entirely different story.....and it depends on which steel you are using and what tempering cycle is used. 440C is tempered around 425 degrees F.......pretty low temp and pretty easy to screw up the h/t if you arent careful..........ATS 34 is tempered up much higher and so you can get it as hot as 750 degree F without any problems....

for rule of thumb, if it turns blue you are screwed!

Trace Rinaldi · Mar 17, 2003

Tom I thought it was, if they turned blue you got everything BUT screwed..HAHAHAHA

tom mayo · Mar 17, 2003

no, when it turns blue you have moved....................to.........i da ho!

Epsilon · Mar 17, 2003

SkaerE,

ok, so pre-heat treat i can really hog out the metal for profiling and be generally ok right? (as long as it doenst reach 1350 or so)

Bullseye.