They make epoxy and zinc primers for powder coating. They are baked on before the final powder coat is applied. Rim seem to see especially tough abuse so they would be a good place to think about using it instead of going straight over the metal.



I have a no mar bar for my manual tire changer. When removing the tire, the single nylon end rides along the lip of the rim. When installing a tire, the double nylon end rides along the inside of the rim groove (area hidden by the tire after it's on). The way it works is the only opportunity I have to damage a rim is while removing the old tire. The nylon end is soft enough that it doesn't damage anything. I have spare tips because the nylon end is not supposed to last forever. If I can do that at home with some cheap tools, any tire shop can do MUCH MUCH better.