"cherry red" case hardening compound

[GOATMAN]

Steel Treating Compounds YouTube - Instant Steel Case Hardening: demonstration
anyone ever trie this stuff? pros or cons?

[Woody]

They make several "instant case hardening compounds" casite or something like that is one of them. Be very careful when using them, get the MSDS and read it thoroughly before use. Some of these compounds contain very toxic materials. I have heard that some contain cyanide but I have not documented that myself.

It is a very slick video but instead of the bluegrass music it would have been nice if they would have mentioned what steel they started with. It wouldn't be hard to get a Rockwell 55 our of a piece of W-1 but it would be much more difficult to get the same results with a piece of mild steel.

[Quenchcrack]

The speed at which carbon diffuses into steel depends upon the temperature and the difference between the %carbon in the steel and the %carbon in the compound or atmosphere. At 1750F and a carbon potential of .6% in the carburizing compound, a .20% steel will absorb carbon at the rate of about .007 inches per hour. Don't expect much from an "instant" hardening powder.

[philip in china]

Is it possible to make my own hardening powder? I have only very basic materials here but would be interested in trying. Recipe anybody??

[Finnr]

You can case harden with charcoal by enclosing the charcoal and the item to be hardened in an iron box, or a wad of clay , anything that won't burn, and putting the whole works in the fire for several hours. Somewhere I have a table with how long to leave them for a certain depth of case.
Finnr

[philip in china]

So I get the steel, clean it up, put it in a lump of clay surrounded by powdered charcoal. Then I put it in a fire and, effectively, forget about it for a few hours? Is it as simple as that? Then eventually take it out, crack ioff the what is now pottery and clean up the steel again. I will try that next time I am going to have a hot and long lasting fire- possibly next time we roast a whole animal.

[KNeilson]

White sugar has lot of carbon in it. Ive been told that pow tunnelers in ww2 used it to case harden their digging tools. These were usually a tin can that had been slash cut and a handle added. As a youth I had limited results trying this,I dont bother now as I prefer to use a more appropriate material such as tool steels or other more high carbon steels.......Kerry

[Finnr]

Pretty crude Philip but I have done it. Wrapping the item in leather and encasing it also has worked for me. Jack Andrews has some formulas in New Edge of the anvil.0ne being:
Hardwood Charcoal 55%
Barium Carbonate 20%
Sodium Carbonate 15 %
Calcium Carbonate, 10 %

I haven't tried all that, just carbon bearing stuff!

Be sure the clay is fully dried. Steam bombs are nasty.
Bring to critical temp.
An example given is Mild steel held at 1600 for seven hours will have about 1 /32 of an inch of penetration.

I tried it on a lark , I figured if a backwoods blacksmith could case harden the frizzen of a flint lock rifle I should be able to as well.

Give it a shot, the most you can lose is your test piece. And you still get a nice roast critter!
Finnr

[John B]

Not exactly carburizing, but will work to surface harden mild steel, non toxic, and easily available, this is a very old method to use.


Take a spoonful of wholemeal flour, add two spoonfuls of salt, add a little water and make into a smooth paste.

Heat the end of the item to be hardened until the paste will stick to it, when you have the item coated where you want it, heat the area to a bright red heat and plunge the item into cold clean soft water. The coated area will be appreciably harder.

An ideal way to make a quickie tool more hardwearing.

[NateDJ]

John B That sounds more like a type of super quench than case hardening. The use of salt in water will make it quench faster/harder so would attaching the salt directly to the blade with a flower glue make it even faster?

Will have to give it a try next time I need to get some a36 a little harder.