I want to add something else about the warmed oil quench. People ask me all the time how warmed oil is a faster quench than cool, room temp oil. It has to do with the thickness or the viscosity of the quenchant. The thicker the quenchant is, the slower it quenches the piece. What happens when you heat something?....The parts that make it up begin to move faster. When the oil is warmed up, the little parts that make it up begin to move faster, this makes it thinner and more viscous which makes it a faster quench. You can actually see the difference of the thickness of the oil with your own eye. Try this and see. Put a stirrer in room temp oil....lets say 70 deg. F. Lift the stirrer out, and watch the oil drip. Take note of how thick or thin it is. Then, do the same thing with oil that has been heated to 130 deg. F. Notice how much faster it runs off of the stirrer and how much thinner it is.
Now, back to the topic!