How to slightly "bend" a blade so that it centers while closed ?

[Lansky1]

I have a really nice Case slimline trapper with SS (stainless trusharp) blade that doesn't center very well when closed, which bugs the crap outa me. Over the years I've put on the leather gloves and tried to forcefully bend blades & have never been very successful - it takes a surprising amount of force to bend a blade (even slightly) and one time I broke a blade clean off at the tang trying to do this, other times it loosens the pins and the blade will wobble. I've never tried to use heat as I know nothing of this & have always been afraid of ruining the temper of the steel.

I would really like to know if anybody has been successful in slightly bending common stainless steel blades so that they center properly in the bed & exactly how you might have done it ??

Thanks very much guys - would really appreciate any feedback or ideas ...

John

[Jeffinn]

Someone in here posted a video quite awhile ago about a technique called “crinking” where the blade is struck at the right location and bent to center it. I’ve done it a few times with mixed results (a few successes and a few broken blades). It’s a valuable technique for multi-blade knives where you’re trying to get 4 blades to fit into the knife well without rubbing.
One of the knife repair books had some info on this too but it wasn’t called crinking (Ill have to dig out the book and look it up).
In my opinion, crinking a blade is a high risk, low reward technique but might be necessary if a blade is rubbing a liner or another blade. I guess it depends on how much an off centered blade bothers the owner.
Hope this helps.
Jeff

[Jeffinn]

From The Complete Book of Pocket Knife Repair by Ben Kelley Jr.:

[kootenay joe]

The 'trick' would be how hard to strike the blade. And you need the correct hammer. Likely a series of light taps would not do anything.
kj

[Steve Warden]

Likely a series of light taps would not do anything.
kj

And just one tap too hard...

[Jeffinn]

Likely a series of light taps would not do anything.
kj

And just one tap too hard...

Exactly! I don’t believe a series of light taps would work (it’s possible I guess but doesn’t seem likely).
It depends on the manufacturers hardening process as well. If it works and the blade comes into the centered position you’ll be doing a little happy dance. If it doesn’t work you may end up with a set of handles in your hand and you’ll likely learn some new cuss words!

[bighomer]

Go to the Great Eastern forum, Oscar posted a tour of the factory and they show how they do it.

[Lansky1]

From The Complete Book of Pocket Knife Repair by Ben Kelley Jr.:
EEC2F087-4F3A-4452-82EA-8ABB37BFBA92.jpeg

Wow - great info Jeff - really appreciate you posting that technique - I’ll see if I can come up with a jig like that & practice before I try it on a good knife.

[Berryb]

The real problem would be; if it works pretty well the first try you would be tempted to make it perfect, Whack Snap. at least that's the way my world works.
Bruce

[Reverand]

Look at the knife frame from different angles. I fixed a Case slimline trapper for a friend where the blade was off-centered and the frame looked weirdly warped on the end. Turns out the pivot pin was bent. Everything centered perfectly on a new pin!

On the GEC video that I saw, he was trying to crink it at (or near) the tang, rather than along the length of the blade.
I can attest to getting one almost perfect, needing just one more tap ... then walking away in disgust when it snaps in half.
I am not a fan of crinking.

[Brumbydownunder]

Gentlemen ... please take into consideration the older repair books (I have a couple) do show the cutlering method above ^^^ and it does work ...BUT they were very much written about knives with carbon steel blades which are more forgiving than some of the modern steels
Most GEC have carbon steel blades but Lansky1's Case certainly won't ....

I learnt this very expensive lesson the hard way ....

This S&M blade just did not like this method

[rea1eye]

I had a Case Barlow where the last 15% of the blade was slightly bent.

This was offered in the forum based on my question several months ago:

Post by Froe » Mon Aug 05, 2019 6:39 pm
"I have had some success in straightening softer bent blades by repeatedly tapping the concave side with the ball of a ballpein hammer. Don't get in a hurry and don't pound on it. You will leave some light dings in the blade so I only do this if I'm going to make it a user knife. Have a good heavy solid steel surface behind it. I just straightened two bent blades on a Swiss Buck that I got at the flea market. They came out straight and I'm carrying it now.
Keith"

I tried the ball-peen hammer approach. I used the hammer several times and then squeezed the blade between two hard pieces of wood.
I went back and forth probably 5 or 6 times. The result is not perfect but much better. AND did not ruin the knife.

Bob

[glennbad]

As was mentioned above, this is a HIGH risk operation. It could literally go either way. Some krinks are quite easy, some just don't work. I've probably only had what you would call success about 20% of the time.

To me, on a production knife like that, the off center is not a big deal, but I understand it bugging you.

[OLDE CUTLER]

Yes, I will also add my testimony that they do sometimes BREAK!

[Dinadan]

If I were trying the operation I would clamp the knife in a vise with the pivot between wood blocks so that the blade does not develop wobble. Then I would take a pair of vise grips and clamp the blade between a couple of thin wood pieces so that the blade does not bend, assuming that it is straight to begin with. Then just gently bend with the pressure at the tang.

I have done that with a couple of cheap China knives where the blade was at an unacceptable angle when open. It worked with the China knives in the sense that the blade angle was changed and the blades did not break. I am sure that Case has a different, hopefully better steel, so who knows.

It is funny how different things bother different folks. I do not pay much attention to how a blade centers in the blade well. But I cannot abide a knife where the blades skew off out of line when open. I have been told more than once that it is the crinking to make the blade center in the well that leads to the skew when open. That may be true, but I have plenty of knives with blades that align perfectly straight open and closed, so I am not too interested in carrying a knife where the blades skew out of alignment.