Tom.........You're a better man than me. All the talk of heating , tempering , etc . is above my pay grade , and I'm too blessed old to learn such operations. Got this neighbor , half Navajo , rest Apachi. His painting art looks like photographs. I showed him how to scratch build long rifles , and he built three. His true love is knives. He too does all this heating and dumping blades in oil , etc. . Neck knives up to some that could cut the heart out of a buffalo , on the run. I save my worn out 600 grit 1" x 42" gun metal working belts , to put the razor edge on his blades. He brings a new just finished knife to me with a "stone sharp" edge , and I get to put what he calls a "medical sharp " edge on his creations. All it takes to get a "medical sharp " edge is , two or three passes across the worn out 600 grit belt and a pass or two over a hard buffing wheel w/ rouge. Oh my.....sharp , sharp ,sharp. When we eviscerate a deer , his knives will go right up through the ribs to the windpipe for easy removal of heart and lungs. Sorry............in the weeds ,again.............oldwood