Old timer told me to quench in motor oil instead of water, still not sure if he was joking

So I was at a hammer-in last summer and this retired smith, must have been 70, sees me quenching a knife blank in water and goes "you're gonna crack that thing, should be using used motor oil". I laughed it off but he looked dead serious. Tried it on a different piece of mild steel and it definitely gave a darker finish but the smell was awful and I worried about fumes. My buddy says the guy was just messing with me because he cracks up every time someone new tries it. Have any of you actually used motor oil for quenching or is this some kind of hazing ritual?

3 comments

3 Comments

davis.noah1mo ago

...and then old boy probably had a smoke break lined up while the new guy was gagging on burnt oil fumes. I've heard this one going around for years. There's a reason we use water or brine or actual quenching oil, not something that's been sitting in a 1992 Ford F-150's crankcase. The smell alone should tell you it's a prank - that burning petroleum stench will stick to your clothes and shop for a week. Plus the smoke is genuinely bad for you, no joke. Sounds like you got initiated, just like the rest of us.

michaeltorres1mo agoMost Upvoted

Man, that brings back memories. @davis.noah is right about the smell sticking around. I got hit with the same trick my first week at a shop. Spent the rest of the shift with my jacket in a plastic bag and still caught whiffs of it driving home. Ended up just leaving that jacket in the garage for a month before the wife let me bring it back in the house.

janah831mo ago

Ha, yeah that jacket thing is all too real. I still have a hoodie from like 2018 that I swear still smells faintly of burnt gear oil even after a dozen washes. My dog won't even lay on it, he just gives it a sad look and walks away. At this point I think I just keep it as a badge of shame, you know?