Cracking: similar phenomenon crocodile scales rule cracks appear on the surface of the film.
● Flexibility in strong coating (such as latex primer) coating on a high hardness of the coating (such as alkyd enamel).
● When the primer is dry topcoat.
● Since the oil-based paint natural aging temperature fluctuations; sustained loss of elasticity of the paint film stretching.
Workaround: eradicate the old paint and polished surfaces. Large-scale construction, you can use heat gun to improve construction efficiency, taking care to avoid igniting paint or substrate. Surface use high-quality latex or oil-based primer primer, then paint quality exterior latex paint.