Well, at least the grain looks good...

pnHXrqb.jpg
That sucks. I had something similar happen 3 nights ago. It was only $20 of steel and 7% of my week.

I'm pretty sure that mine was trying to straighten the blade out of the quench. What happened to yours?
 
That is a nice grain. I saw a grain the other day that looked like granulated sugar
 
Guess...

AEB-L. I made the mistake of clamping two identical rough ground .198 thick blades together in Sub-Zero. This works for UNGROUND blanks only ( hindsight). One warped waaaay far. I did 2 tempers at 400. Then did a third with shims either side of apex and clamped the apex down. After an hour, I pulled it and went to cool it off in the sink......yeah, I know. ...
 
Looks like there was a crack in the spine before tempering, maybe I’m old and can’t see but there is a dark area near the spine in the cross section photo.

Hoss
 
DevinT said:
Looks like there was a crack in the spine before tempering, maybe I’m old and can’t see but there is a dark area near the spine in the cross section photo.

Hoss
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Not a crack. It was a slight harpoon shaped spine. It broke about 1/4" from that cut, so I don't think the cut had anything to do with it. It was a about a 3/8" radius.
 
The rapid cooling from 400F didn't cause it. It was already there or caused by over clamping. Cooling from 400 to room temp won't cause warp or cracks. The structure is the same and no dimensional changes happen. It may expose an already made crack that was invisible.
 
I doubt it cracked prior to trying to straighten it. I was thinking the shock just pushed the damage done when I clamped it that last hair over the edge.
 
A little tip I learned the hard way. If you clamp AEB-L for sub-zero (highly recommended) make sure it's the same thickness of steel on both sides of the blade. The side of the blade that cools faster will bow that direction. So clamp the blade between 2 identical bars of steel. DONT clamp a bunch of blades togather hoping thy will keep each other straight. Thy will bow out on each side and be really nasty.
 
JTknives said:
A little tip I learned the hard way. If you clamp AEB-L for sub-zero (highly recommended) make sure it's the same thickness of steel on both sides of the blade. The side of the blade that cools faster will bow that direction. So clamp the blade between 2 identical bars of steel. DONT clamp a bunch of blades togather hoping thy will keep each other straight. Thy will bow out on each side and be really nasty.
Click to expand...
Now you tell me. I have had success doing it with un ground blanks.
 
Kevin McGovern said:
Guess...

AEB-L. I made the mistake of clamping two identical rough ground .198 thick blades together in Sub-Zero. This works for UNGROUND blanks only ( hindsight). One warped waaaay far. I did 2 tempers at 400. Then did a third with shims either side of apex and clamped the apex down. After an hour, I pulled it and went to cool it off in the sink......yeah, I know. ...
Click to expand...

If you didn't remove the 3 straightening pressure points prior to cool-off under running water, tight apex-to-spine bending radius may exceeded fracture point when blade temperature drops below 140F into water temp (thermal contraction = lowering fracture point). nvm - if you did removed the straightening clamps.
 
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