Warped blade straightener

[will52100]

Not pretty, just thrown together out of scrap. I have a cleaver that developed a minor warp during heat treat and I needed a better way of taking the warp out, preferably while still hot from the tempering cycle. Basically 3/8 flat bar, 1 1/2" wide, 1/2" black iron pipe cut in half and a small strip of flat bar welded in the half round cuts of pipe to enforce them and bent over to make easy position changes. A half piece of pipe under the bolt to act as the presser to even out the pressure. The whole thing is small enough to clamp a blade and stick blade and bender in my heat treat oven. Just tried it out and works great. Do one full temper, let cool, put the blade in the jig and lightly tighten, put in the oven and let everything come up to tempering temp for a bit and tighten the 7/16" bolt to induce a set. Put it back in the oven and let it soak at temp some more.

I normally use a three point clamp set up in a vise to do the same thing, just mild steel round bar with holes drilled in and pins to set it on the vise jaws. Trouble is this is finicky and takes long enough for the blade to cool and I've broken more than a few doing it this way.