Making your own case hardening compound.

Edited By Doubletop on 13/02/2012 09:19:37

I went to the NZ suppliers who are advertising kasenit as being available. They are actulay selling "Cherry Red" as an alternative. ( I think it may have been Ian who pointed me to them)

US manufacturers here, plus instructions and MSDS

http://www.rosemill.com/category_s/20.htm

Its not cheap here but I belive that to just be opportunistic wholesalers. NZ is a small market

Pete

The main ingredient of Kasenit is described in literature was Sodium Ferrocyanide. But it also contained an accelerator this was Barium Carbonate. The Barium Carbonate was in a crystallised form and included water in the crystals. If you remember when you heated Kasenite it stuck to the metal. This was because the water of crystallisation melted. At this point I can see the Gnomes of Elfinsafety getting agitated because both Barium Carbonate and Sodium Ferrocyanide are poisons. Barium Carbonate is used in rat poison. Sodium ferrocyanide is added to food salt as an anticaking agent.

rdgs

Dick

At room temperature sodium ferrocyanide is perfectly safe due to the strong bond of the cyanide with the sodium. As Dick said, it is used as a food additive.

Concerns have been expressed over its safety at high temperatures where it could become disassociated hence the banning of the original of Kasenit by the Health and Safety police. However it is still used in the coating of welding rods

Russell.

Richard, I don't know if Kasenit (I still have enough for several lifetimes) contains Bariun Carbonate. But what I know is that G. Lautard recommanded it in his recipe for pack case hardening. As carbon he told to make it from walnut shells and plum/abricot/cherry stones.

Many years ago I tried to get it, but our administration chemist denied me the permission (although it is in a poison category which is not very high and I had - theoretically - the right to get it)

Seems times have changed a bit; a couple of weeks ago I discovered that now I could order it online and no-question-asked from a supplier for the ceramic hobbyists. It is used for some glazings. Rather cheap also, iirc. If soneone wants to know more, I can post the link to the (German) catalogue.

Greetings, Hansrudolf

Sodium ferrocyanide (sodium hexacyanoferrate (II)) is safe because the CN- ions bond strongly with the Fe++ ions, not to the sodium ions. Its sale is not restricted, AFAIK, by UK poisons legislation.

Barium is a Schedule 1 poison in all forms which are, or which can easily be made, soluble in water. For example, barium sulphate is one of the most insoluble salts around and is thus not restricted (indeed it is ingested in large amounts as an X-ray opaque material) but barium carbonate is readily dissolved in dilute mineral acid. Barium is a non-cumulative heavy metal poison and any soluble salts should be handled with care. You are quite right that you should have a right to purchase barium carbonate, though you would have to give a reason for acquiring it and may have to sign the book.

David

Edited By David Littlewood on 21/03/2012 12:16:33

Russel Yes Sodium Ferrocyanide does give off Hydrogen Cyanide (HCN) at high temperatures but only if water is present. Kasenit contained both Barium Carbonate and something else. These formed a coating on the metal. This was done by using the water of crystallisation which boiled off long before the Ferrocynide started to disintegrate into HCN.

If you want to see this get some Epson salts (Magnesiun Sulphate) and warm them up. You can also see the same effect with Borasic Acid (borasic powder) you get from the chemists and use as flux –both of these contain water in their crystals-

Neither the makers of Kasenit or any other company would want to be involved in a Coroner’s Inquest so their products were safe for normal use. I dare say if you ate a ½ kilo or so you would need a few hours with the undertaker.

The lethal dose of HCN can be as low as 1.5 mg/kg of body weight. HCN is also lighter than air. This is why it is not used in military chemical weapons. I weigh somewhere over 75 kgs so to kill me you would require a minimum of 90mg of the stuff that is a large amount as a gas in air. It took upwards of 1/4 hour to kill all the folk in an Auschwitz gas chamber. Elfinsafety do not care they see their job is to keep you safe and damn the consequences

Handrudolph Barium Carbonate is used as a cheap glaze in the ceramics industry, glass making, and in rat poison so go and see a potter, borosilicate glass maker they may give you the few grams that you need

I think we had best leave it at that

P.S Calcium Carbonate can be used in place of Barium Carbonate as an accelerator but it is not as reactive.

Rdgs

Dick

Edited By Richard Parsons on 21/03/2012 13:01:25