I have been asked by several lately about my quenching technique for big knives and Dirks. So, I thought I'd put it in here for others as well.
Remember, this is Baryard Smithing, not Lab work. Not sophisticated at all.

There are several ways to do it. I personaly just edge quench. My oil tank is horizontal. A lenght of 8" pipe cut long ways with ends brazed on and legs under it. I warm the oil to about 150-190 F. Its a guestimate temp. Its uncomfortable if you get it on your hand. Most of my blades are rather thick in the spine area, 1/4" or a little thicker. Some as much as 3/8".
The blades are from 1 1/4 to 2 1/2" wide so there is plenty.
The edge is very thin. So, I heat the blade until the edge itself is cherry upto half the width of the blade. Then I immidiettly place it into the oil. Holding it so only 1/3- 1/2 the blade is immersed. Hold it so until the red leaves the rest of the blade. May take a few minutes. It will still be to hot to handle. Then put the whole blade into the quench.
When you remove the blade after 5-20 minutes, you will need to clean it up. I use a wire wheel or heavy duty scratchpads. Then you need to polish it up some. Depending on the blade and intended use, after quenching I bake in the oven at 550-600F for 4-8 hrs. Take it out and immideatly quench in hot water. Let it cool off. You may then need to buff it or whatever. Should be spring tempered and tready for fitting the hilt up tight.