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Tempering question??


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I'm working on my first knife and have finshed shaping and am ready to heat treat and tempur...I'm clear on heat treating. My question is specifically with tempuring. I've read through a lot of posts here and have a lot of ideas on what to do but still many questions. So here goes...

Basic skinner knife. Small with a three inch blade.
I've read using an oven set at a particular temp for a set time
I've read heating the spine of the blade slowly to a straw color stopping prior to reaching the blade.
I've read something about placing the spine of the blade on a thick piece of steel and heating that piece with a torch...
SO what do i do??

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The HT of a blade should follow its intended function. Since this is a small blade and a skinner (not going to be put through heavy abuse like a brush knife/heavy chopper) there is not much of a need to differentially temper the blade (tempering the spine more than the edge) by heating the spine with a torch until a blue color, and the straw color runs out close to the edge or heating a large piece of steel and setting the spine on that until the temper colors run to the edge.

My recomendation for tempering in this case is to use the oven. Do you know the particular steel you used for the blade? That will effect times and temp. For most blade steels in small to medium knives I'd recomend 375 - 400 F, running at least 2 separate temper cycles of a minimum of an hour a piece. 3, 2 hour cycles being quite good. Depending on the steel, you might have to temper higher or longer (higher carbon steels that harden deeper, steels with alloying elements that effect carbon diffusion rates etc.) check the edge with an edge flex test to determine if the tempering temp was high enough. If you wanted to differentially temper the spine, I recomend tempering the entire knife in the oven at slightly lower temperature first (350-375F), then after that pull the spine. Keep the edge cool (submerge in water) and then heat the spine with the torch (to about a deep blue color). You'll want to repeat the torch heat at least 3 times.

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