View Full Version : Heat treating CPM 420V


Ray Rogers
11-18-2001, 04:02 PM
Has anyone got a good formula for heat treating CMP 420V? The Crucible website lists the temperatures but not the timing.

Would appreciate any advice you may have....

JHossom
11-18-2001, 04:35 PM
Their book recommends 10-30 minutes, but that's for thicker sections. I would think 10-15 would be plenty for knife baldes. The book also suggests using a salt bath or interrupted oil quench, which is really aimed at getting the temperature down to 1000F as fast as possible.

Ray Rogers
11-18-2001, 09:27 PM
Thanks, Jerry. That's about what I figured but I only have one piece of this steel so I thought I'd check with the experts...

JHossom
11-18-2001, 09:43 PM
Whoa Ray, I'm no expert. Paul Bos does all my tempering. I was just reading what was in the book. Good luck with it.

Rob Simonich
11-20-2001, 11:13 AM
The only thing I would add is use the longer soak times on these high alloys. Also, rather than interupted oil, you can use a press quench for a very fast quench. Ive gotten good results that way.

Gary Mulkey
11-20-2001, 06:02 PM
Rob,

I'm going to show my ignorance but would you explain the process of a press quench?

Gary Mulkey

Rob Simonich
11-20-2001, 09:07 PM
Gary, the press quench is nothing more that quenching the knife between 2 thick pieces of steel or aluminum. Aluminum works the best. There are several ways to do it but I take the knife out of the furnace, strip the foil off and very quickly lay it on a 1/2" aluminum plate on the floor, put an aluminum plate on top and either stand on it for a minute or put my anvil on top. You get a very fast quench and blades come out flat. It dosent work on tapered tangs however.

Gary Mulkey
11-21-2001, 07:42 AM
Thanks Rob,

I may play with it some on some 3V that I've had some warpage problems with. I know Crucible recommends that you quickly quench to 1000 degrees and then a slow air quench to room temp. If I can get to where I can judge how long the press quench takes to get to 1000 and then remove the blade it might cure the warping.

Gary

s mcfall
11-27-2001, 08:27 AM
does paul bos have a web page or e-mail?

thanks,
stan

JHossom
11-27-2001, 09:35 AM
No webpage, but here's his email.

PaulBos@buckknives.com

Bill Foote
11-28-2001, 05:48 PM
He does a great job and can give it the cryogenic soak.
His prices are good, too.
Paul Bos
1900 Weld Blvd.
El Cajon, CA 92020
619-562-2370

JHossom
11-28-2001, 06:13 PM
BTW, I believe Rob Simonich does heat treating too. Knowing the knives Rob makes (I have one), he's as good as they come as well.

Rob Simonich
11-28-2001, 10:38 PM
Thanks for the plug Jerry.......but................I am only heat treating my own stuff at this time. It was taking too much of my time and I had to prioritize making knives over heat treating. In fact I will be using Paul Bos on some bigger batches. You cant find anyone better than Paul!