Sanding Marks

Sanding marks in the substrate show in the topcoat after paint drying.

Common Cause

1. (1) Incorrect substrate preparation: insufficient filler or poor quality and excessive coarse sanding paper.

2. Poor sanding tools or wrong sanding method.

3. Insufficient paint thickness of topcoat.

4. Sand with no sanding board in flat finishes.

5. The primer prior to topcoat is over thick and insufficient drying time for the primer.

6. Incorrect preparation of the old existing paint finishes.

 Repair

(1) Sand with extra fine paper, then polish.

(2) If the surface is seriously defected, sand, then re-spray.