Coating defect

Crawling and cissing

The wet paint pulls back from spots on the surface and leaves bare or thin areas, sometimes with a speck of contamination in the middle.

Crawling and cissing: the surface as you see it, and a schematic cross-section.

Causes

Oil, grease, silicone or wax on the surface.
The liquid paint has a higher surface tension than the surface it is on; waterborne paints are the most prone.

Prevention

Solvent clean before other surface preparation (SSPC-SP 1).
Keep silicone products away from the work.

How it is assessed

Visual. Cissing spots are small and round; crawling is the severe form, with paint gathered into beads.

Telling it apart

Cratering (fish eyes): Craters are separate round spots with a rim. Crawling pulls the paint back over a wider area into beads or islands.
Holidays and misses: A miss from application leaves bare steel without beads of paint round it. Crawling leaves paint gathered at the edges of the bare spot.

Repair

Remove the affected paint, clean the surface thoroughly, and recoat. The specification and the coating manufacturer have the final word on the repair procedure.

1 practice item in the members area mentions crawling and cissing (CIP 2: 1).

Try it in an exam-style question. The free readiness check shows the question style, explains every answer and gives you a dated study plan.

Take the free readiness check See the tracks

About this page

Written from coating practice and the published rating standards, in our own words; the drawing is schematic. Checked on 2026-10-14; errors go in the corrections log. CoatMentor is an independent study aid. It is not affiliated with ISO, AMPP, SSPC, NACE International, ASTM or FROSIO.