I promised a video on this a while back and finally got around to making it. The forced air charcoal furnace took a few attempts to get right, but this one worked like a charm. It was able to get a fairly large package of parts up to around 1500ยบ and keep them there for an hour. The only problem I had was the cheap craft SS foil burned through. That allowed some oxidation of the parts, but they still hardened up just fine.
Tom
Tom, how long ago did you buy your can of Kasenit? I thought it was no longer available and replaced by Cherry Red?
They changed the Kasenite formula - certainly for what is sold here in the UK, as it originally contained various cyanide compounds as enhancers.
The new stuff is not a sticky as the old. You used to be able to heat a part to red heat, dip it in the tin, bring it out covered in a nice coating and re-heat with a torch. The new stuff stays powdery and blows away with the torch :(
Doesn't matter if boxed like Tom did it.
I'm intrigued whether it's got the name Case Hardening as it makes a hard 'case' around the part, or from the box (case) that it was originally done in, in a Furness.
I still have a can of the "old" Kasenit but the places I always used to find it no longer carry it, and offer the Cherry Red now instead.
I bought mine from Brownells many years ago.
I did notice on the McMaster site that they offer two different "types" of case hardening compound. They don't give out the brand name in 99% of their items so you never know what you are going to get. But they show a "dip" formula and a "pack" formula. I'm assuming the "pack" version is just a courser grind? I'm wondering which one Tom used in his video because it looked pretty fine, like my can of the "dip" version?
Mine is the dip kind. I think the pack kind just lacks the binders to make it sticky.
Tom
Thanks Tom,
Saving this for the future, good production, covered and explained the total process clearly.
Well done
Greg
Thanks Greg. It was a fun project.
Tom
Tom, have you done any experiments to see how deep a case you have achieved?
(It shows up in a cross section when polished and etched like testing a weld for penetration)
What thickness was the SS foil Tom?
It was .002" Darren, but I have no idea what alloy it is.
Tom