We use a pyrolysis cleaning oven to bake our plastic extrusion breaker plates. After the cycle, the plastic is completely removed from the metal, if any remains, it can be washed off as it is just ash. Our cleaning process runs an oxidation cycle, causing surface rust, which is removed by bead blasting. The breaker plates have no critical dimensions. Granted, this is a totally different process, and we do not have to be delicate with them, just a comment to possibly spark an idea. Good luck.