Orange peel is a fine, irregular surface texture resembling citrus skin. It is most visible on glossy, transparent, or painted parts and often becomes more pronounced in highly stretched areas.
A prolonged heat soak can soften or disturb the surface layer even when the bulk sheet remains formable. Local radiant imbalance produces the same appearance in isolated zones. The defect may also originate in the sheet through extrusion texture, incompatible regrind, contamination, or earlier thermal damage.
How to diagnose it
The texture pattern should be compared with the heater map, wall-thickness pattern, and mold surface. Texture concentrated beneath a hot zone indicates local energy imbalance. A uniform defect that is already faintly visible before forming points toward sheet quality. If the pattern matches the tool, the issue is surface transfer rather than orange peel generated during heating.
Process correction
Heat exposure should be reduced without moving the sheet below its forming range. Depending on thickness and heater response, a shorter, more controlled cycle may be better than a long low-output soak. Local screening or zone adjustment can be used where a defined region overheats. Changes should be confirmed with measured sheet temperature and a repeatable part, not by appearance alone.