Looking at this from a long way away, it seems to me that if this 'Experienced Gunsmith' Mr.Landers is using a torch in his colouring process, he is not Colour Case Hardening the part. I strongly suspect he is using the torch in conjunction with a chemical called Tincture of Benzoin, which, when applied to a polished metal surface and irregularly heated with a torch, will produce a range of colours which the uninitiated can mistake as CC Hardening.
I would love to give a piece of Mild (Low Carbon )Steel to Ed.Landers and have him apply his colour case hardening technique to it. I would then apply the simple file test, I have a strong feeling that the file would plough off filings at every stroke whereas a correctly CCH treated metal would have the file skid off the surface without marking it.
The Faux (false colouring) technique was even described in one of America's leading gun magazines some years back. Prettying up an old or indeed a new action by the application of faux colouring in not, and never will be, Colour Case Hardening. The faux colouring method does not harden the metal it is applied to, in any way at all. CC hardening can only be applied by the Bone/Charcoal or molten Cyanide method. There are other methods of case hardening of course, but these do not produce the required or desired colouring.
The application of faux colouring and then describing it as CC Hardening is nothing but Shade Tree Gunsmithing as the Americans so delightfully describe this form of firearm butchery. Here in Britain such false claims would result in prosecution under British Trade Description Laws.
Harry.
Last edited by Harry Eales; 08/16/11 03:16 AM.
