[beater68427]

In a conventional oven that will heat the metal too slow, metal will hold water, when it heats slow you can see the moisture pull from it, in a slow heat process it will get a golden glow from rusting during the slow heat process, changing the finish too a more brown color, also it might be hard to keep up on the oil process without the bolts cooling. The process posted is the nicest hardest finish process I have found, a repeat is sometimes needed for the correct shade and practice helps, When set up to do a multitude of bolts it only requires a small amout of time in the heat and oil process. This is by no means a new process I learned this in Metals class 25 years ago for hardening steel I always liked the finish you could get and I use it for a multitude of things.