Orange peel appears when the melted film gels before it can level. A certain amount is normal for powder and is graded against numbered smoothness panels from 1 (heavy) to 10 (glass smooth). It gets worse with film build outside the supplier's range, fast-gel powders, coarse particles, back ionization, slow ramp and old powder. Film build in range, better charging control and a matching gel time reduce it.
Customer rejected the cabinets for orange peel, they want a 7 on the smoothness panels and we're at a 4.
Past the supplier's range, thicker is not smoother; once back ionization starts, more film only adds texture.
Also heard as
- peel
- OP
Related terms
Flow
How far and how smoothly melted powder spreads out before it gels, which sets surface smoothness.
Gel time
How many seconds a powder takes at a set temperature to go from melted to a rubbery gel that no longer flows.
Back ionization
Tiny electrical discharges inside an overcharged powder layer that repel new powder and pit the finish.
Film build
The thickness of the cured coating, usually given in mils or microns.