i have a kiln and have been tossing around the idea of using it to harden 1095 steel. to anyone who uses a kiln for this do you submerge the whole full tang knife in the heated oil or just the blade part. i have been using a one brick forge and have been just hardeding the blade. are the any advantages either way. thank you
You will generally get a little more scale using a kiln because there's no fuel to burn up the oxygen like in a gas forge. You can put a small peice of charcoal in with the knife to help burn up some of the oxygen and it will help some. I mix up some very thin refractory cement like satanite and put a thin wash on the blade and that helps prevent scale too.
I like to just quench the cutting part of the blade, but lots of factory knives harden the whole knife and you don't see them breaking all the time. If you do a good draw after hardening, it should be fine either way.
1095 requires a radically fast oil so you will need to use something like Parks #50 to inhibit the steel from reverting back to pearlite. And it doesn't like to be overheated, so a kiln can work well if you have your temps dialed in.
I recently got oven, I love to bring knife to temp and quench
Fully submarge there will be no fire (flar up)otherwise there maybe
The only thing I can think of and why I fully submerge blade is because I don't like to see quench line in damascus.
then I resofen whatever I want soft (spine or tang)
I think you are asking whats the difference in full submerge .
if you fully submerge in parks 50 like Karl says you will have to resofen tang to do any work needed.
there is also stuff to use to stop scale if you need to know