For several years now I have made knife from old HC or WHC marked railroad spikes. I have sold these knives with the understanding they make okay knives not good knives due to the lack of carbon. After purchasing a Hardness Rockwell C Tester, my story is changing.
The blades are forged, roughed out and set up. With a torch using the Bill Moran method of heat treating, I thermal cycle the leading edge of the blades three times allow to air cool until the "shadow" moves thru the blade. On the last cycle the blade is quickly quenched leading edge down tip point north (for what ever difference that makes) in a stiring fasion in 30 weight ND motor oil.
Because of the lack of carbon in the knife I do not bother drawing these blades. If anyone breakes one of my RRS knives I can afford to give them another one. I want to keep all the hardness I can in these blades.
The knife is finished and polished. I have tested several blades expecting to see hardness of 40C to 45C at best. I was supprised at the solid 57 HRC that I am consistantly getting.
I hope this information is usefull to someone. I am open to comments as well. I dont know everything. In fact the more I learn the more I reailize how much I dont know. This process works for me.....
Gary - Antley TX Knife and Forge, Groveton Texas