So then really your just fine grinding the pistons for a blue printed fit and finish?, with a polished final surface finish?
You previous description of lapping the pistons were of a honing method/motion, which is why I assumed you were after some sort of cross hatched fine finish on the pistons.
My mistake then I guess, I just assumed you were doing something more than just basic engine blueprinting, I'm sure the language barrier is not helping in that matter.
