TIL tempering a blade in my kitchen oven was a bad idea

I was trying to temper a little paring knife and figured my home oven would work fine. Set it to 400 and left it for an hour, came back to find my wife's cookie sheet warped and smoking. Took me three more tries and a toaster oven from a garage sale to finally get the temp right. The whole thing cost me about 3 days and $15 for the used toaster oven. Has anyone else had a kitchen tool disaster from forging?

2 comments

2 Comments

king.jordan1mo ago

Nailed it with a thrift store toaster oven myself. Picked up a beat up one for $8 at a garage sale, wired a cheap thermocouple through the door to actually track the temperature. That 400 setting on most ovens is a lie anyway, mine was hitting 450 easy. Burned through two old pizza pans before I figured out I needed a fire brick in there too. Now I just stick to the toaster oven for small blades, keeps the wife happy and my kitchen intact.

kai8071mo ago

Wait, aren't you just making things way harder than they need to be though? @king.jordan, I get the garage sale score but that thermocouple hack sounds like a fire waiting to happen, especially with a toaster oven that's already running 50 degrees hot. I'd rather drop $40 on a proper heat treat oven from Harbor Freight and know the temps are right out of the box than mess around with wiring my own sensors into a crusty thrift find. Pizza pans don't hold enough of a thermal mass anyway, fire brick or not, so you're still getting hot and cold spots all over the blade. For the cost of two burned pans and a brick, you could have just bought a used kiln from a potter and been set for life.