Rotors





Are you picking fly crap out of the peppar ? Probably, most folks won't notice the difference and there is enough slop in the OEM caliper design that C4's use to accommodate machining tolerances.
Those machines would really shine when resurfacing rotors for fixed caliper, multi-piston setups. It is really important with fixed caliper setups to have the sides as parallel and free from runout and machining error for optimum braking. I shimmed the rotors on the '65 I had to .001 TIR (total indicator reading) (I was used to working to +.0000 -.0002 tolerances or better). The brakes would haul that car down from 100 like I threw out an anchor. The ones on my '96, even though I completely rebuilt them, have no comparison in feel as those brakes did. I guess that is why the high end (Brembo, etc) use a fixed caliper, multi-piston design.
I worked with all kinds of grinders when I was younger. Surface, Blanchard, ID-OD grinders, tool grinders, I ran them all. These are not as precision as an ID-OD grinder, but they are good enough !!
Here is a vid of them in action.











