Ya well i tried the motor oil and the knife did not harden. So i used a real light oil i found at work and it worked. Weird thing is i decided to just fully harden the blade so i just fully quenched it. Well long story short my crappy forge if thats what u want to call it (made from a turkey deep fryer n some firebrick) did not make the whole blade uniform in heat. The edge was hotter than the spine. The whole thing was non magnetic but the spine did not harden like the edge did. So by dumb luck it came out differencial treated. I did do one at work in the oven and it hardened fully but my ones at home have all been differencial treated.