Thread: Heat Treat Prep

Originally Posted by baldy

When you guys say take off sharp edges, to what extent are we talking? I'm starting to worry about my jimps now.
Would you consider them risky to quench.
They are not as deep as they look, probably 1mm deep on the deepest one. The groove kind of bends around to the side of the tang making them appear bigger
Thanks
Grant

Don't worry about the jimps. They run through the thick part of the tang which is structurally strong.
Additionally, The tang gets cooled with the same temperature so there is no stress gradient like there can be between a thin edge and a thick spine.

As of this writing, of all the razors I've had a hand in heat treating, the jimps have not yet produced a stress riser. I have to say that a heavily file worked spine and some jimping has caused me to hold my breath at the critical moment. I can only remember one or two cracks and they were directly related to very acute angles.

It's possible to draw out the hardness of the tang after heat treatment, then file stuff in. Diamond files work pretty well on even the hard stuff, but it's a lot of hand work either way. Perhaps consider just enough of a cut to mark where you want the jimps, keep it shallow and radiused, then after heat treatment, cut in the sharp definition.

This kind of thing should be a point of discussion between the blade maker and the heat treater before the quench.