A paint depth gauge measures the total thickness of paint on a panel, in microns. A human hair is around 70 microns across, so the margins are small.
What we look for
Consistent readings suggest original paint. A sudden jump can mean filler or a respray. A low reading tells us to work gently, or to leave the area alone.
Why it matters
Polishing removes clear coat, and clear coat doesn't grow back. The readings tell us how much margin there is, which is why you get a copy for your records.
Readings and figures here are general examples.
