Heat treating CPM 420V

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....

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.

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...

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.

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.

Rob,

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

Gary Mulkey

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.

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

does paul bos have a web page or e-mail?

thanks,
stan

No webpage, but here's his email.

PaulBos@buckknives.com

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

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.

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!