I agree with everything other than using motor oil. That’s somewhat dangerous as the flash point is below the flame point which means that it will sustain a fire even after the hot part is removed if it’s large enough to start one when it’s plunged in. I know a lot of people don’t use, or even know about quenching oil, but it should be used because it’s just the opposite and will not sustain a fire. It’s also pure. Used oils can contain noxious substances that are bad for the health and sometimes for the metals being hardened. That’s particularly true for motor oils which can contain chemicals that you shouldn’t breathe when they get that hot.
I generally use a magnet for bringing carbon steels to critical temp.
please explain
Great video. I think you meant temper it (to the straw colour) after hardening, not annealing it.
you are 100% correct. nice catch!
I agree with everything other than using motor oil. That’s somewhat dangerous as the flash point is below the flame point which means that it will sustain a fire even after the hot part is removed if it’s large enough to start one when it’s plunged in. I know a lot of people don’t use, or even know about quenching oil, but it should be used because it’s just the opposite and will not sustain a fire. It’s also pure. Used oils can contain noxious substances that are bad for the health and sometimes for the metals being hardened. That’s particularly true for motor oils which can contain chemicals that you shouldn’t breathe when they get that hot.
you’re right! i will get some quenching oil for the next class.
Make a Vid aboot your Forge Furnace.. Two pieces of C Channel.
sure. i’ll make a video on shop furnaces for heat treatment. we have a couple electric furnaces and a few types of bearing heaters too. great idea !
@@Stubbornnut When is this video coming? 🙂 Really interested in that gas forge design.