Case hardening powder, any advise?

I need to case harden a few small items, (6mm dia x 30mm). They only need hardening on one end. Normally I'd just use silversteel, but I just used mild steel, it's all I had at the time.

So I've bought some of this stuff off Ebay

**LINK**

The instructions say to heat to 800-900 deg C and put in the powder, leave for half hour and quench. I was expecting to have to reheat and quench.

Has any one used this powder?

Thank you

Jim

I have the same stuff. Usually heat to bright red and dunk in the powder and stirr it about, lift out and heat back up then quench. You can heat & dunk more than once if you want a deeper case as each time adds more carbon.

I don't leave it for that long, no point on a small item as it will have cooled after a min or so. and certainly would not need quenching.

Best to put it in a metal tin so you don't melt the pot if the part touches it.

Edited By JasonB on 19/04/2018 07:26:47

I had some cheap(ish) nondescript case hardening powder from one of the well known ME suppliers. I could not get any case hardening with it. I even tried making a box out of large screwed pipe fittings, filling with item + powder, heat ad nauseam, then dunk - but still no joy.

Purchased proper Kasenit and had no further problems. This needs heat to bright red, dip in and it forms a sort of crust over the item. Heat a bit more, then dunk. Repeat as required.

You get what you pay for I suppose - Caveat emptor.

Martin

Thank you!

Pretty much what I was I thinking Jason. I'll have a go later and report my findings!

Thank you too Martin, hopefully it'll work out! Its one of those annoying little jobs that, if I'd made it from the proper stuff, it'd be done now!

Jim

Is proper Kasenit still available, I thought the health and safety people had that banned a long time ago.

Doug

I believe it was banned some time ago by H&S people who were ignorant of chemistry. It contained Sodium Ferrocyanide which is not poisonous and is available in food grade! They confused it with the very poisonous HCN, NaCN, etc.

It should still be available as food additive E535.

Russell

Edited By Russell Eberhardt on 19/04/2018 10:07:19

My understanding is that the second heat is to refine the grain structure of the component. The part would be allowed to cool after the carburising and then hardened in the usual way .Colin

Are you saying food additive E535 is usable as Kasenit? I've never figured out where to get Kasenit.

Add sugar or molasses.

Careful with ferrocyanate in larger quantities, it can release cyanide if exposed to acids. Not enough to be an issue in food quantities.

It should work on its own but I suspect the original Kasenit recipe also included some form of free carbon such as carbon black or ground charcoal as I seem to remember it being a grey colour.

Russell

Hmm - doesn't the stomach contain hydrochloric acid??

Russell

The beta contents are Molasses, Charcoal and Sodium Carbonate Solution so why add more molasses?

Wasn't LBSC's advice for case hardening something like this?
"get your old boots, cut into strips of leather and pack them around the item in an iron box, seal with fire clay and put in the fire, leave overnight until cool."

nuff said?

Just been to look out the good pot of case hardening compound. It is Blackgates own brew, and the tin says it contains Ferrocyanide. Can't remember just when I bought it, but less than 10 years ago for sure, probably more like 5 years.

Apologies for claiming it was Kasenit, but it does handle just like Kasenit.

Martin

Some for sale here...

**LINK**

George.

Wow. Do people really pay nineteen quid for an empty tin?

Brian

It would seem I have kept mine too long, the can is strating to dissolve

Can't be much cop, if it can't protect its own tin