Cracks of different lengths and widths appear on the coating surface, spreading in all directions.

Causes

1. Excessive coating thickness of the paint film.

2. Repair coating applied over old paint surfaces with existing fine cracks.

3. Use of incompatible coating materials, causing mismatched hardness or flexibility (e.g., hard polyester putty or filler mismatched with thermoplastic acrylic T.P.A topcoat, leading to cracks due to tension from expansion and contraction).

Prevention

Use only compatible coatings as recommended by the manufacturer, and control the coating thickness within the standard range.

Repair

Sand the cracks thoroughly to ensure all traces are removed, and repaint as required. For flexible surfaces, ensure that coatings include flexing additives (such as elastic-flex additives).