warp in the quench

tmr

Active Member
I have been doing something recently that i first tried because i was curious and it has been working extremely well for me.........i dont usually have a lot of problems with warping in the quench but as i do forge a bunch of filleting knives out of circular saw blades occasionally i get some warping......i recently had a blade kick during the quench and as soon as i came out of the oil i pressed the blade in my 30 ton press with flat dies and it came back to perfectly straight and i noticed that the steel from my press dies acted like a heat sink and removed a lot of the residual heat from the quenched blade....i have tested these blades for hardness and flex and they are preforming great......i am going to the press as soon as i remove from oil and notice any warp while there is still heat in the blades.....has any one else been doing this?.........comments or thoughts are welcome
 

Chris Railey

KNIFE MAKER
Placing the knife in your press to cool is a version of a maneuver many of us use to prevent or hopefully correct warps. After I oil quench most knives I place them between two aluminum plates with a bag of sand on top until they completely cool. I have seen people clamp them in a vise too.
 

tmr

Active Member
thanks for your input.....i also plate quench with aluminum plates but i had only been doing it with foil wrapped stainless blades that were air hardening ......i never thought to do the same with carbon steel.....probably because of the oil on the blades and me rushing to press as soon as possible while there was still heat in the blade......also thanks john for the picture of your plate clamp....i am going to copy that.....looks great
 

Chris Railey

KNIFE MAKER
Yep. What you’ve done is called a plate quench.

I use aluminum plates as Chris described. I mounted mine in a cheap woodworkers vise.

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John you just gave me an idea. I have always laid my hot blade on one plate and then quickly put the other plate on top but I have always worried about uneven cooling due to one side of the blade being in contact with the plate sooner than the other. If I mount your set up 90 degrees counter-clockwise then I can hold the blade between the plates and close the vise until both plates contact the blade at one time. I am glad you thought of that...
 

BossDog

KnifeDogs.com & USAknifemaker.com Owner
Staff member
I have about exactly this setup also. Works well and is less prone to screwing up.
Harbor Freight sells these wood clamps pretty cheap. Just drill and tap a few holes.
recommended.

Yep. What you’ve done is called a plate quench.

I use aluminum plates as Chris described. I mounted mine in a cheap woodworkers vise.

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