How It Looks
Causes
- Application of a colored coat on top of ground coat that has been sprayed dry.
- The air bubbles that form during the application because of high viscosity, low air pressure or because of high ambient temperature that lead to a very quick drying.
- Old pinholes that were not sanded well.
- Poor application of the putty.
- Fiberglass bodies.
- Insufficient mixing of polyesters.
- Insufficient priming of polyesters.
Preventive measures
- Avoid spray dusting of the initial coats.
- Use recommended viscosity (thinning ratios) and air pressure.
- Sand well ground coats.
- Use correct technique when applying putties.
- Hold the knife at 60-degree angle in order to avoid rolling the putty and allowing the penetration of air bubbles.
- Mix polyesters thoroughly.
- Use polyester spray filler (574 with H353 hardener) whenever possible.
- Ensure sufficient filling of polyesters.
Remedy
- Remove damaged finish.
- Sand and apply polyester spray filler (574).
- Prime and paint.
Note
You should never try to fill the holes with successive coats of primer filler.