Casehardening compound?

[tpy77]

MA0600 Kasenit $4.95

Casehardening compound for iron and steel. This is a process of hardening the surface of metal by forcing carbon into the steel surface with heat of over 1000 degrees Fahrenheit. This is called the “Martensitic Structure.” Do this by heating the part to a nearly white hot color, dip it in the Kasenit powder which cools off the surface somewhat, then remove the object from the powder, reheat to a white hot ad quench it in water. Especially keen for hardening frizzens, tumblers and sears. Will not make spring steel. Will not leave the fine mottled blue but does give metal a pleasing gray color. Also fine for hardening cast hammers, lockplates and pans. 7 oz bag with directions is enough to do 500 sear or more. Non toxic. Heat small pieces with propane torch or over gas stove. Heat larger pieces with forge or acetylene torch.

 

[Numidian]

Or just use an oxy-acetylene torch to harden things.... Its no more difficult to do than using their "special" powder...

 

[Numidian]

This is from a friend of mine who has built 30+ ak's using this method

Heat treating the ghetto doc fortin way

Items needed:
5lbs of salt (kosher salt is cheap)
bag of clean playground sand
bottle of Dawn liquid
magnet pickup thingie or a magnet on a stick

finish your receiver (bend/weld) weld on your rails, drill your trunnion holes as described before.
Mix the salt and Dawn in a 5 gallon bucket of hot water (to dissolve the salt) this is your quench bath. find a big pan to be able to cover the entire receiver with at least 2 inches of sand all the way around. this is your annealing tool. turn your home oven on to bake at 500*

the areas tempered are the fire control group holes and the extractor edge that faces forward.

Get a MAPP/oxy or oxy/act torch. heat up them until a bright orange/red color and a magnet will no longer stick to the red hot areas (around 1600*) and IMEDIATLY quench in the bath till cool. do ONE SIDE AT A TIME. dance the torch between the 2 holes so you can do them both at the same time and not untemper the hole you just did
heat,stick magnet, heat, stick, heat, no stick, quench

once all holes are done then bury it in the pan with sand and stick in the oven till it reaches 500* and then TURN OFF THE OVEN ! and walk away.
remove it when cool

 

[biermkr]

That sounds pretty easy. How do you measure the temp of the receiver when it is in the sand?

 

[Numidian]

That sounds pretty easy. How do you measure the temp of the receiver when it is in the sand?

It's not really important...the idea of the sand and the oven is to just make sure the temperature comes down slowly

 

[biermkr]

I was referring to this part:

once all holes are done then bury it in the pan with sand and stick in the oven till it reaches 500* and then TURN OFF THE OVEN !

 

[Numidian]

I was referring to this part:

Set the oven to 500 and when it reaches 500 turn it back off... So you're just worried about air temp in the oven, not the actual temp of the reciever

 

[Half-cocked]

The first part of the operation (getting the parts red hot, then quenching them) hardens the steel. However, this makes the steel brittle. Bringing it up again to a not-quite-as-hot temperature, then lowering the temperature gradually, "tempers" or toughens the steel so it's still very hard, but no longer brittle. You would leave the part in the oven long enough to be confident that it's thoroughly and evenly heated, then let it cool down gradually. I would recommend letting it soak at 500 for 30 minutes to be sure.

The most important thing is to let the steel cool sloooowly. Don't pull it out of the oven. In fact, if you can gradually lower the oven thermostat over several hours, in 25 degree increments, even better.

 

[biermkr]

I thought even the tempering process needed to be more precise than that.