How to straighten 5mm thick blade?

[Clack]

Hi all,

Unfortunately, the blade of my knife has a bend in it. I would like to get that straighter. The question is, how?

I thought about drilling out the pivot pin and removing the blade. Heat it and then clamp it between the vice. However, I am afraid that the knife will lose its hardness due to heating, so I don't think it is a good solution.

Is it also possible to straighten the blade between a vice without heating it?

Another option is to try to straighten out the bend with a bronze hammer. Dont know if this will create some damage on the blade..

Or try to press it straight under a press?

Do you have any suggestions for me? Thank you guys..

[Modern Slip Joints]

I sucessfuly straightened one much thinner Case stainless blade by gripping it with two pairs of pliers. It had to be bent waaaaaaaaaaaaaaaaaaay past straight to spring back to straight. Based on that I think squashing a cold blade to flat in a vise would not work. After mentioning my success here multiple knife mechanics wrote blades more often break before they reach the point from which they would sping back to straight. Heat is another ball game.

[Bill DeShivs]

The blade will have to be over-bent to straighten it. Doing so without heat is risky-especially with hardened stainless.
Heating the blade will discolor it, so it will have to be polished out. The heat treating will be affected, but it really won't matter, as I doubt you'll be cutting much stuff with it.

[Clack]

Hmm sounds very risky all and hard to do. I will reevaluate the situation and see whats the best option. Maybe removing the blade and sending it
to an black smith.

[orvet]

I am not a blade smith, but as I understand the process, a blacksmith could anneal the blade and straighten it, then re-temper it.
There is risk in doing that as it will likely change the grain structure of the metal, making it coarser and more prone to breaking.

[ScoutKnives]

If there is enough blade sticking out to the center of the bend then place it on the flat part of an anvil and hit the center of the crown / bend of the blade and hit it with a brass hammer . One or two smacks will probably do it .
Always a risk but this is the method I use and have had great success .
Mike

[BIGHEAD]

Looking at your pictures itlooks like more than a bent blade is going on especially looking at the frame being warped/spread.

[Clack]

If there is enough blade sticking out to the center of the bend then place it on the flat part of an anvil and hit the center of the crown / bend of the blade and hit it with a brass hammer . One or two smacks will probably do it .
Always a risk but this is the method I use and have had great success .
Mike

This sounds a bit more pleasant. I'm going to try this.

But if I understand correctly, I have to place the blade flat on an anvil with the warped side upwards? And then give it some smacks on top of the warp?

[Clack]

Looking at your pictures itlooks like more than a bent blade is going on especially looking at the frame being warped/spread.

Nah its only the blade. The thing what you see is the backspring. Thats isnt 100% straight either but not a big deal.

[ScoutKnives]

Yes crown side up .
Make sure you’re accurate with those smacks .
For it to bend like that in the first place without breaking I would think the tempering isn’t great . I would bet it bends back quite easily . Good luck .
Mike

If there is enough blade sticking out to the center of the bend then place it on the flat part of an anvil and hit the center of the crown / bend of the blade and hit it with a brass hammer . One or two smacks will probably do it .
Always a risk but this is the method I use and have had great success .
Mike

This sounds a bit more pleasant. I'm going to try this.

But if I understand correctly, I have to place the blade flat on an anvil with the warped side upwards? And then give it some smacks on top of the warp?

[Clack]

Yes crown side up .
Make sure you’re accurate with those smacks .
For it to bend like that in the first place without breaking I would think the tempering isn’t great . I would bet it bends back quite easily . Good luck .
Mike

If there is enough blade sticking out to the center of the bend then place it on the flat part of an anvil and hit the center of the crown / bend of the blade and hit it with a brass hammer . One or two smacks will probably do it .
Always a risk but this is the method I use and have had great success .
Mike

This sounds a bit more pleasant. I'm going to try this.

But if I understand correctly, I have to place the blade flat on an anvil with the warped side upwards? And then give it some smacks on top of the warp?

Thank you

[ThatWeirdKnifeGuy]

Use three pieces of bar stock or dowels in your vice. 2 pieces on one side, the third on the opposite side and positioned in the middle of the other two. Put the blade in the vice with the concave side next to the two dowel pieces, the convex next to the one piece, with that one positioned on the crown of the bend. Closing the vice will bend the blade past neutral and can hold it there. Its a bit more controlled than a hammer, and you can more accurately apply heat, even using water or clay to protect the heat treat. Still no guarantee against breakage though.