'De-Warping' after Heat Treat

Dealing with the warped knife blank- a common occurrence when heat treating. As soon as the knife is quenched, you want to check to see if it has warped at all. If it has you can sometimes straighten immediately after the quench (before tempering). Another way I like- is to clamp the knife to a pre-heated piece of thick steel before putting it in the oven for tempering.