4130 test blade

4130 for a knife blade huh? Interesting. I didn’t think the popular alloys for firarms could reach adequate hardness for an proper edge. Looking forward to seeing the outcome.
I was wondering the same thing? I thought 4130 topped out at about 50 RC? prolly a nice tough knife but edge holding?

If my memory is correct a cold treat will help it also?

Freds Edge

Well-Known Member
Ken , thanks for the info I am going to go the super quench as outlined in the article. The second blade I am making I will quench in the fast quench oil I get here in Detroit.

Freds Edge

Well-Known Member
The answer as to will it harden is answered , yes it will harden how hard is another question . I did not temper the blade as per the recommendation I found at a machinist forum and snapped the thread off the tang , that is now fixed and the blade is going in for a one hour temper maybe two cycles.


Well-Known Member
Fred, can you do Rc testing? I've read RR spikes can hit 50 Rc or so with that super quench stuff. While 50 Rc isn't really "hard" for high end knives, it's amazing how many older carbon steel knives were not much more than that.