Is this tang warped?

K

KenHash

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Sep 11, 2014
Messages
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Received a Gyuto with a "broken handle". Looking at it, it seems the tang itself is warped. If my observation is correct, (1) how in the world could this happen with a cooking knife, and (2) can it be corrected? Appreciate any views. Thanks very much.
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Looks pretty warped to me. Maybe you could try an agressive tapered tang to get it flat. If you know the steel you can try to fix it with a temper cycle. I have fixed a warp in the past by clamping the knife to a thick flat bar of steel and tempering it. I have only tried it immediatly after quenching. Im not sure how well it will work with a knife after its been fully tempered. You could also try to soften the tang by heating it up (while keeping the blade cool) then bending it straight. Good luck.
 
I would not do any of the above suggestions. Your going to create more work for your self or wreck the knife. This is a simple fix if it is indeed warped. Strip the scales off and get a good look at it. If it’s warped then go to your anvil and use a ball peen and gently use the ball end f the hammer and tap the inside of the bow. This expands the metal very slightly and will straighten it. Just take it slow and get a feel for how it moves.
 
The peening inside the hollow works too... But why not just anneal and cold hammer on an anvil? I think the risk of cracking the tang is minimal if you take it to a dull red a couple times (or even just do the straightening AT a dull red). The integral bolster will help keep the heat from bleeding into the blade, but you can always suspend the blade in water while heating up the tang.

I don't know, this just looks like such a simple fix - hammer the reverse side of the bowed section (closest to camera) to flatten, flip and hit the opposite bend further away to bring straight. Looks like there might be another little bed in there too (closest to camera).
 
Wow that is a heck of a warp.
Was it put through the dishwasher or left in water for a period of time?
 
JT, if the tang is hardened, won't trying to bend while it's hardened cause it to break? Seems like heating dull red, then straighten would be less likely to cause tang to break. If hammering with that pointed hammer works on hardened tang, then it's a new one on me and I've learned something new today.
 
I'M thinking bent. Heat and lightly hammer. Wrap a wet towel around the blade so as not to lose he hardness.
TJ
 
JTknives said:
I am surprised more people don’t know about the hammering technique.
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Agree if it is hardened. I cant see the pics, but if the gyuto is laminated or differentially hardened, you can just tap it lightly on the high spot. If it is hardened, peening the inside of the bend works great.

If it is not hardened, peening will still work, but is a lot more work than just minor cold bending.
 
TJ Smith said:
I'M thinking bent. Heat and lightly hammer. Wrap a wet towel around the blade so as not to lose he hardness.
TJ
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Why heat when some mild taps with a ball been will solve it? I don’t see any advantage to it. If anything you have now lost any hardness that is in the tang.
 
stezann said:
JT is right, good advice.
That's an excellent video tutorial from Berardo, worth watching!!!
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JTknives said:
Why heat when some mild taps with a ball been will solve it? I don’t see any advantage to it. If anything you have now lost any hardness that is in the tang.
Click to expand...

I just did this the other night with a small ball peen hammer on a 3v blade that warped on me and it worked like a charm. Took a little time but WELL worth it. I’ll be doing this from now on.
 
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