Serious question, has anyone else had trouble with that new 'quick quench' oil?

I bought a five gallon pail of the stuff last month after seeing ads online. Used it on a batch of twelve leaf spring knives and every single one came out with micro cracks in the spine. That's about $200 in steel and a full day's work gone. I went back to my old Parks 50 and the next batch was perfect. What quenching oil are you all using for tool steel now?

3 comments

3 Comments

wader712d agoMost Upvoted

Had a buddy try that stuff on some axe heads. Same story, hairline cracks right near the eye. He was furious. Swears by warmed-up canola oil now for his big stuff. Seems like the fast oils are just too harsh for some steels.

amy_coleman2d ago

Doubt it's the oil's fault every time. Seen guys blame the quenchant when they overheated the steel to begin with. @wader71, your buddy check his temps? A hairline crack near the eye sounds more like a stress point from forging or a bad heat cycle. Fast oils work fine if you know what you're doing.

lucasw842d ago

Man, what if it's not the oil speed or the heat, but the axe head design itself? Some of those old patterns have a super thick eye that cools way slower than the thin bit. That mismatch in cooling rates can cause crazy stress right at that spot. A fast oil might make that problem worse, but switching to canola is just hiding the issue. Maybe the real fix is tweaking the shape so the whole thing cools more evenly.