heat treat warp

dhannon

dhannon

Joined
May 9, 2000
Messages
143
I've become frustrated with the blade warping during heat treat. I understand the entire metalurgy thing and the induced stresses, but... I have been finding that many blades (15%) come back from heat treat warped too much to use. OUCH!

I keep the blade symetrical. I grind equally on both sides (in steps). And I keep the blade under 130 F (I don't use gloves and keep my fingers on the blade to monitor the temp).

Help! Any secrets I should know here? Can heat treaters correct for this? Or straighten the blades?

Dan Hannon
Hannon Bearpaw knives http://www.freeweb.pdq.net/dhannon/hannon.htm
 
Since you are in Houston AND if you are working with air-hardened steel such as D2, 440 series, ATS34, etc then I would have it taken to Texas Knifemakers Supply or go see Ron over there and talk to him. He is pretty good at even keeping my blades straight. They had a "show and tell" there about 2 months ago on heat treating that was pretty informative.

If you are working with carbon steel then they may have information on who to contact regarding that as well.

Craig
 
Thanks for the replies. I will look into the heat treater for straightening methods (and willingness). I believe I will have to take the latest, a bowie, to Texas Knifemakers Supply for straightening.

I take it that this is not so uncommon?

Dan
 
I think Paul Bos is very good at using a quench press. Paul can interject here.
If the heat treater will use this method it will help with warp. Paul understands what we are after from what I have read. Some heat treaters dont.

The surface grinding comment about is a good one. The grinder puts stress in the surface of the side you grind.



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Web Site At www.darrelralph.com
 
Dan: Robert is wright, If you have to take materal off, you must do it evenaly. I would say about %50 of all blades I heat treat distort to some point. Most Heat Treaters that cater to Knife Makers have several methods of straightning, one being quench plates, another being hot straightning fixtur!s, and doing it by hand right after quench. Hope this helps. Paul.
 
Ive also had some luck with some steels by throwing the blades in the kitchen oven at 500 deg and soaking them an hour or so and then cooling before heat treat. Might try that.

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www.simonichknives.com
 
We knife makers put our soul into the knives we make.

We all end up with some warped blades.

Suggests something about us?
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OK.....your in for it now...I am grinding a MILLION 420V blades and Jerry sent me a bunch of 3V...........
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plus Ive been collecting fire ants to sneak into your bed when you get over here......hahahahahaha!!
 
You didnt specify what grit you are taking the blade to. Ive found that I get very little warpage on blades if Ive taken them to at least 220 grit on the grinder. I think it help releive stress.
 
When I used to do my own heat treating (before discovering Paul Bos), I found it pretty easy to straighten ATS-34 and 440C blades by hand while they were still warm from the hardening oven.

Rob's idea is interesting. Maybe I'll do that before I send the next batch to Paul.

Paul, I owe you a BIG apology. I never should have sent that 3V to Tom. He's not mature enough to handle it.
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Jerry Hossom
www.hossom.com
The Tom & Jerry Show
 
Will intricate, asymetrical file-work and carving cause a blade to warp during heat treat? Should I wait until after the blade is treated to add these embellishments?
 
Wulf: You have to do the file work and engraveing befor heat treat, you wouldent be able to do it after,the blade would be to hard. Those to proceses dont contribute that much to blade distortion. Paul.


 
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