Enlarged sand scratches caused by swelling action of the topcoat sol vents around the repair area.
Causes
- Too coarse of sandpaper used
- Improper reducer used
- Undercoats not thoroughly cured before applying color
- High film build of undercoats
- Improper cleaning
Prevention
- Use appropriate grit sandpaper being careful not to sand through soft or sensitive substrates
- Use appropriate reducer for spray environment
- Do not apply excessive film build of undercoats
- Use compatible paint system
Correcting
- Ensure undercoats are thoroughly cured before topcoating
- Sand the affected area and seal before topcoating
