[lincpimp]

Depending on the material the pinion is made off, the heat and quench may or may not work. I use a torch, and 10w30 motor oil. Slowly heat it up till it is red, taking care to not melt the metal. I use a metal can with the oil in it. Carefully knock the pinion into the oil, be careful it will smoke and hiss! Do not try to grab it with pliers, as this can damage the hot metal. I use a vise, or anvil to heat on, the place the can next to it and tap the pinion in with a screwdriver.

Let it cool, and do it again. The second time will help harden it further. I had success with the emaxx internal gears that I made into pinions, but they are decent steel that can be hardened. Trial and error will show if you pinion is made of decent material...