Part of my winter project this year is RA seals and some porting. I am currently cleaning rotor housings. I made some .125" aluminum plates to cover mating surfaces and bead blasted the outer sides. While I used ScotchBrite Rollock discs to clean the mating surfaces on the steel sections I am thinking this is a no-no for the aluminum ones? They almost apear to have a machined step on them or someting? Are these supposed to be totally smooth, flat or not. I just want these partrs super clean and thats where I'm at. Any advice would be appreciated.

 

Nevermind, I guess I jumped the gun w/that stupid question. Further and closer inspection told the story. Rollock disc works great. Just let the speed do the work and keep it moving. Dont be stingy w/the discs either.