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View Full Version : Yet another heat treat process question!



Johnny Roberts
03-20-2010, 10:13 AM
Hey guys. I searched high and low for some information on this and couldn't find anything.

I got my new oven from USAKINFEMAKER.COM the other day. Pretty excited about having more control over the entire process and really lookeing forward to drawing my own springs for folders.

I heat treated some scrap ATS-34 and it turned out great. Then I realized that I am not how to approach the tempering process.

I have the recipe for 58RC. 400 degrees for 2 hours - 1 time and for spring temper fo 43 to 45 RC, 1200 degrees for 2 hours - 2 times.

My question is do I need to leave it in the foil for any reason?

AND

When tempering - When I remove it from the oven, do I plate quench it as I did during the hardening process?

Many thanks guys. I don't know what I would do without this site and ya'll as a resource!

Lonestar JR.

David Broadwell
03-20-2010, 10:31 AM
Hey guys. I searched high and low for some information on this and couldn't find anything.

I got my new oven from USAKINFEMAKER.COM the other day. Pretty excited about having more control over the entire process and really lookeing forward to drawing my own springs for folders.

I heat treated some scrap ATS-34 and it turned out great. Then I realized that I am not how to approach the tempering process.

I have the recipe for 58RC. 400 degrees for 2 hours - 1 time and for spring temper fo 43 to 45 RC, 1200 degrees for 2 hours - 2 times.

My question is do I need to leave it in the foil for any reason?

AND

When tempering - When I remove it from the oven, do I plate quench it as I did during the hardening process?

Many thanks guys. I don't know what I would do without this site and ya'll as a resource!

Lonestar JR.

Having your own HT oven does in fact give you more control, including the freedom to do only one or a few blades at a time. If I were a production maker with several standard models that sold well, I'd send my blades out because it would be pretty cost effective, but I sometimes make only one blade at a time.

When I HT any stainless that's wrapped in foil to protect it from scale I use the quench plates. After I clamp the blade which is still inside its foil baggie I snip off the end. After a minuted or so I pull the blade out of the foil. It's below any scaling temperature by then.

For tempering I put them back in a 400 degree oven without any foil. That temp won't even color your ATS, much less scale it. After each temper cycle I hand them from the tangs until they cool, or if at the end of the day I'll just open the oven door and turn it off. No need for foil or the plates.

The only thing I see wrong with your tempering recipe is that blades should go through 2 cycles of at least 2 hours each, not just one cycle. Same for the springs.

David

SBuzek
03-21-2010, 02:01 PM
Lonestar
You need to do 2 tempers,the first temper converts retained austinite into marstinite then the second temper,tempers the new marstinite. on the 400 deg temper foil is not needed,but on the 1200 deg I put mine back into an old fol packet to cut down on oxidation.
Stan

Craig
03-22-2010, 02:35 AM
So we should be seeing some slip joints from you soon? :D

Just remember on the temper like David and Stan said 2 hours 2 times.

If you have a hardness tester temper a little lower and then test. Raise the temp a little at a time to get the hardness you want. The temp shown on your oven may be above or below the actual temp inside.

Craig

Cubane
03-22-2010, 04:29 AM
So we should be seeing some slip joints from you soon? :D

Just remember on the temper like David and Stan said 2 hours 2 times.

If you have a hardness tester temper a little lower and then test. Raise the temp a little at a time to get the hardness you want. The temp shown on your oven may be above or below the actual temp inside.

Craig

Yes see my build off thread for problems with oven temperature. I went out and bought and oven thermometer to double check the temp in the oven to make sure it isn't too hot.

Alistair

Johnny Roberts
03-22-2010, 03:12 PM
Thanks for the information, guys.

You have saved me a lot of trouble and mistakes already. Yep, Craig. I want to see how I fair at this slipjoint thing. Having fun so far. Very different than full tang blades.

Lonestar JR