Surface finish decides how a galvanized steel coil looks and paints.
Regular spangle shows the crystalline zinc pattern and suits unpainted roofing and ducting.
Minimised spangle reduces the pattern, while skin-passed coil is rolled lightly for a smooth, slightly matte surface that paints cleanly and forms without stretcher strains. Oiling protects against white rust in storage;
dry coils suit immediate painting.
Chromate-free passivation is now the default for compliance. Specify spangle, skin-pass, oiling, and passivation together.
