so... after heat treating - the black coating... any good for regular old coating?

Josh Muller

Josh Muller

Joined
Jun 22, 2003
Messages
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just tried out my 2 brick black forge (2 soft firebricks covered in black fireplace repair caulking/mortar), and heat treated two small blades...

and i now have two knives that are coated in what is actually a rather nice looking matt black substance. i expected straight up slag that would be rough and undesireable like when your pounding out wrought iron, but this is rather nice.

how would it do if i just polished it up a little to get off the discolored parts and to even out the matt finished...ness.... ?


im going to have to grind it off anyways, because wow. i had no idea how much more it was going to take to get the grinds even and correct until i had them heat treated and ready for handle slabs (but way off on the grinds). if the finish can be used on the completed knife though, i might consider grinding it down to 99% finished product before heat treating and leaving it on there. gonna have to get another brick to make a single brick forge ,because i set my propane entry hole way to far back, so that its difficult to heat the entirity of a large blade....

only place around here without ordering it is in paso robles (im in santa maria)... good long ride for 1 brick. i might just have to order a few online...
 
Can't answe your question, but you could just clean up two pieces of steel. Finsih the surface as you would a knife, heat treat them both, refinish one like you normally would and do the other with the black gunk on it and see what happens. I'd guess that the black stuff is probably a little more corrosion resistant, but who knows? I know my 1084 is pretty resistant to rust after etching in ferric chloride, so maybe it'll be the next big thing! :D
 
If you had not protective coated the blades you either have decarburation or they were not soaked long enough.

RL
 
The only 'black gunk' coating I get is baked/burned oil from the quench, which has to be sanded off. I get as much of it off as I can in the 10 minutes between quench and tempering oven ...and then get the rest of it off (along with the tempering discoloration) after tempering.
Then, only after all the sanding is done, can one apply the finish, whether it be FC, or bluing, or browning, polishing or whatever.

I suppose others may do it differently, but that's the process as I understand it, at least for the basic carbon steels.
 
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thats the coating im refering to.

the brown stuff is baked on peanut oil. by soaked long enough, do you mean in the oil quench? or soaked in a chemical cleaner?
 
by soak they are talking about how long you let the blades soak in the heat from the forge prior to quench
 
I just ordered a couple bricks from Darren Ellis

Great service, prompt emails and he's just a great guy to deal with. It's nice to keep our business inside the community too :)
 
to get some of the black stuff off you can use vinager. it will dissolve most of the loose carbonization. if you are in a hurry try boiling the vinager but you have to add more to it often because it draws the water out.
 
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