Troubleshooting – Powder Coating Finish-cured Films Appearance

Problem , Cause and Remedy

PROBLEMCAUSE REMEDY
Poor surface flow - too much orange peelFilm thickness too thinIncrease film thickness by adjusting application equipment
Heat-up rate too slowIncrease oven temperature (or):
Modify oven baffling to increase heat rate.
Powder resin type or formulaCheck with powder manufacturer
Gloss too low for high gloss powderIncompatible powder contaminationClean application equipment before changing powders
Micro-pinholing from gassingCheck substrate for porosity.
Check substrate for moisture.
Check powder for moisture from reclaim or compressed air.
Check film thickness, coating too thick.
Powder resin type or formulaCheck with powder manufacturer
Gloss too high for a low gloss type powderUnder curedIncrease temperature of oven
(or): Increase dwell time in oven
Powder formulaCheck with powder manufacturer
Contamination in powderSee reclaim system,
Virgin powder contaminated
Check with powder manufacturer
Inconsistent film thicknessGuns positioned wrongCheck and re-position guns so spray patterns overlap slightly
Reciprocators not matched to line speed Adjust line speed(or):
Adjust reciprocator stroke.
Air flow in booth disturbing spray patternConsult your equipment supplier
Defective spray equipmentGo through application section check list
Off colorImproper oven exhaustCheck exhaust vent fan(s)
Bake time too longAdjust line speed
Oven temperature too highLower oven temperature
Variation in film thicknessSee coating appearance section inconsistent film
Powder formulatedCheck with powder manufacturer
Pinholing and gassing through coating surfaceSee coating appearance section,
low gloss
Pull-away or tearing-coating
film shrinks leaving bare substrate
Uncharged powderSee application section, poor charging.
Poor cleaning, metal preparation or dryoffCheck pretreatment equipment dryoff oven and part drainage
Troubleshooting - Powder Coating Finish-cured Films Appearance