A customer's simple question made me rethink my whole quenching setup

I was finishing a batch of kitchen knives last month when a regular asked why I always quenched in a straight tank of oil. He said, 'Ever try moving it in a figure eight? My grandpa swore it stopped warping.' I brushed it off at first, but after three blades came out with a slight bend, I gave his idea a shot. I switched to a wider, shallow pan and started that figure eight motion for about 10 seconds post-quench. The next five blades were dead straight, no post-heat straightening needed. Has anyone else found a small change to their quench routine that fixed a big headache?

2 comments

2 Comments

park.wyatt20d ago

Yeah that's wild lol, I had the same thing happen when I switched to a slower swirl instead of just dunking.

murray.gray19d ago

Wasn't there a whole article about how the speed changes the surface tension? It made sense when they said a slower pour lets the liquid cling more. Totally explains the mess.