How to Anneal a Copper Washer

Annealing copper washers makes them soft again so they can do their job. Some people even recommend annealing copper washers before the first time they are used, as storage can cause oxidation hardening.

Annealing makes copper washers seal properly. Copper washers can be reused virtually forever when they are annealed before each tightening. Copper washers get hard over time so simply putting them back in after a rebuild can lead to leaks. It is a drag to have a fresh engine leak from the head nuts.

The process is simple, heat the washer until it glows red, then cool it by dipping it into water.

I didn't know this when I made the video. I have been educated that copper doesn't need to be slowly air cooled to remain soft after annealing. That's because it is non-ferrous. So simply dipping the hot washer in water is a fine cooling procedure; takes less time too.