The following is the procedure I use for the heat treatment and basic forging sequence of my oil hardening hand forged blades without the use of electricity or gas.

I spend a lot of hours forging each blade and that is one of the main reasons I use natural charcoal as fuel. It allows me longer forging times without adverse effects to blade's functional abilities. I prefer a slower process because I feel that the steel should be slowly finessed into shape rather than quickly. I think that steel can be stressed easier than most makers believe so I slowly arrive at each stage. I use a lot of moderate short hammer blows rather than trying to beat it hard into shape as fast as I can. After a couple hours of forging time I relieve stress in the steel by bringing the blade up to a very even nonmagnetic state and hold at this temperature for a least one minute. I then stop the hand crank blower and cover the blade with some ashes right in the hot forge and let it sit for around an hour. I then pull the blade out and let it completely cool to the touch in still air. I do this every couple hours of forging to keep the stresses to a minimum throughout the process. If the project takes more than a day of forging I leave it in the forge buried in the ashes overnight. This will anneal the blade into a soft relaxed condition and will be in it's best condition for further forging the next day.

When all forging and straightening is completed I normalize the blade three times. To do this I bring the blade up to a very even nonmagnetic state and go about 100 degF hotter and hold there for at least one minute. The blade is pulled out of the forge and clamped to where the blade is pointing at magnetic north in still air until the blade is cool to the touch. I use spring clamps with their handles clamped in a vise for holding the blade. I like the spring clamp because it doesn't have a lot of mass that will draw the heat out of where it makes contact with the blade. I want the blade to cool evenly so all the structural stress can be relaxed and a fine grain size will develope in the steel throughout the blade's length. If you do this process at night without lights you can see how fast anything touching the steel's surface pulls the heat out where it makes contact with whatever is holding it in position. Make sure your clamp doesn't go across the tang from one side to the other. This faster cooling along these contacts points of the spring clamp can cause a weakened line across the tang. Place the hot steel with the clamp in the middle of the tang running along it's length without touching the edges. Practice this in low light and you can quickly see where the clamp needs to be to reduce rapid cooling at the contact points. Let the blade completely cool to the touch. I then rinse the blade in water to cool even slightly further to finalize the step. I repeat this normalizing procedure 2 more times. The blade must not warp during these normalizing steps if they do I straighten them and start the count over. If the blade can go through 3 normalizing steps without warpage then it won't warp during the quench either. I anneal by bringing the blade up to nonmagnetic and bury it in ashes overnight. After annealing I clean off the scale of the blade by soaking it in white vinegar for a few hours. After this I can do any file work or sanding to the blade. I also give the blade a slight presharpening at this point and then dull it with 400 grit sand paper. This sets up my edge for the shock of the quench. It rounds it over slightly so there isn't any heat risers. The edge will be slightly less than 1/32 of an inch before the quench. Check closely for any uneveness or dings or defects in the edge. It should be smooth feeling to your finger tip.

The blade is now ready for the hardening step. I bring the blade back up to nonmagnetic, hold for a minute and I pick it up close to the end of the tang and quench the entire blade into automatic transmission fluid and hold it there until completely cooled. Don't move the blade side to side becuase that can cuase warpage. I move mine up and down slightly to feather the hardening line in the middle of the tang. The blade should be hardened at this point. I wipe the blade clean in some dirt and give it a light sanding so I can inspect the steel's surface. After every step whether it be normalizing, annealing, hardening or tempering I wash the blade off in water to further lower the temperature and finalize the step before I procede. Repeat the hardening step two more times.

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