Also known as: Fish eyes, Craters, Crawling.
What it looks like
Circular craters, often with a raised rim, or areas where the wet coating has pulled back to leave bare or thin patches. In powder coating they are usually called craters.
Common causes
- Silicone contamination, from sprays, lubricants, sealants or even hand creams
- Oil or water in the compressed air supply
- Grease, release agents or fingerprints on the surface
- Cross-contamination between incompatible powders
Prevention
- Keep silicone products out of finishing areas entirely
- Fit and maintain oil and water separators on the air supply
- Degrease properly and handle prepared parts with clean gloves
- Clean booths and equipment thoroughly between powder types
Repair
Remove the affected coating, clean the surface thoroughly with a suitable degreaser, and recoat. Recoating over cissing without removing the contamination simply reproduces it.
Inspector’s note
Cissing that appears suddenly across a shop usually has a single new source. Ask what changed: a new lubricant, cleaning product or maintenance job.