Clay bar does not remove the clear coat. Using a machine glaze or harsh polish might take off a tenth of a mil. There is about 4 to 6 mils of paint maybe a little more on the newer cars. Remember if you want a super slick shine without the orange peel you got to wet sand the clear with 13 micron and machine buff it back to a gloss with fine compound,machine glaze,and the 3m hand glaze. Tape up your windshield and rubber trim and all the edges before buffing,it makes your clean up easier. I buffed hundreds of cars over the past 25 years. Clay bar it makes the polishing job easier.