That old timer who told me to stop quenching in water was right after all

After a customer returned a chisel I made with a hairline crack, I went back to using warm canola oil at 130 degrees and haven't had a failure since, so what made you finally change your heat treating routine?

2 comments

2 Comments

umam954d ago

Hold up, I still water quench most of my carbon steel and haven't had a crack in years. Maybe your chisel geometry or normalization cycle was off instead of the quenchant.

river_hall444d ago

Read something from a retired metallurgist that basically said water quenching is fine if you're willing to accept a certain failure rate, but it's not about skill, it's about physics. @umam95, sounds like you've got good luck or really consistent stock, but I had two chisels in a row fail and that was enough for me. The warm oil just buys you a little more time before the martensite forms, which is nice if your geometry has any sharp corners or thin sections.