Pinhole marks
Definition
Small holes in the new paintwork as a result of improper sanding of solvent boils in lower paint layers.

Causes
- Solvent boils in the (old) paintwork

500 x magnification
HOW TO AVOID
- Either sand out the solvent boils completely or fill them with body filler.
REPAIR
Pinholes can only be repaired successfully by thoroughly sanding the substrate or by filling the holes with body filler.