I am having difficulty machining the finish on these aluminum wheels. I cannot get a clean surface on the face of the wheel where there are no inserts or lug holes. I have tried using all types of coolant, at different pressures, but cannot get the face to have a nice fine finish. Does anyone have any idea what is going on?!? I don't think chips are building up on the tool.
Anyone have any recommendations?! A few people claim that this finish is from the metal itself, but that I do not believe so because the transition occurs at one exact spot.