| Problem | Cause | Remedy |
| Adhesion Poor | 1. Inadequate cleaning or pretreatment | 1. Check pretreatment equipment and chemicals |
| 2. Under cure | 2. Increase oven temp and/or time in oven | |
| 3. Film thickness too high | 3. Reduce thickness by lowering voltage or shorten spray time | |
| Chipping | 1. Powder not fully cured | 1. Check pretreatment equipment and chemicals |
| 2. Coating thickness too high | 2. Reduce thickness by lowering voltage or shorten spray time | |
| Corrosion Resistance [poor] | 1. Inadequate cleaning or pretreatment | 1. Check pretreatment equipment and chemicals |
| 2. Under cured | 2. Increase oven temp or dwell time | |
| Cratering | 1. Contamination wiht other powder | 1. Clean the system and start with virgin powder |
| 2. Inadequate pretreatment of substrate | 2. Check the pretreatment | |
| 3. Contamination with incompatible materials from spray area (i.e. silicone) | 3. Check for presence of incompatible materials | |
| 4. Oil or moisture in air lines | 4. Check air lines. Install filters if necessary | |
| Flow [poor] | 1. Curing temp too high | 1. Reduce oven temp and/or time in oven |
| 2. Preheat oven too high | 2. Reduce pretreat oven temp and/or time in oven | |
| 3. Coating thickness too low | 3. Increase coating thickness by using a higher voltage, longer spray time or more dense powder cloud | |
| Out-Gassing | 1. Air entrapped in siubstrate [i.e. castings, sandblasted parts] | 1. Preheat oven above curing temp and coat hot |
| Gloss Difference | 1. Curing temp too low or too high | 1. Increase/decrease oven temp and/or time in oven |
| 2. Contamination caused by other powders with different flow or gel characteristics | 2. Clean guns, hoses, and hoppers, use virgin material | |
| Impact Resistance/Flexibility [Poor] | 1. Under cured | 1. Increase oven temp or increase dwell time in oven |
| 2. Poor cleaning or pretreatment | 2. Check pretreatment equipment and chemicals | |
| 3. Film thickness too high | 3. Reduce film thickness by adjusting application equipment | |
| 4. Change in substrate thickness or type | 4. Check substrate with supplier | |
| Off colour | 1. Improper oven exhaust | 1. Check exhaust fans |
| 2. Bake time too long or too short | 2. Adjust line speed and/or temp | |
| 3. Oven temp too high or too low | 3. Adjust oven temp | |
| Opacity [poor] | 1. Coating thickness too low | 1. Increase coating thickness by using higher voltage, longer spray time, o more dense powder cloud |
| Orange Peel | 1. Warming up of the coated material is too slow or too fast | 1. Check curing cycle and curing oven, if necessary, contact your powder supplier |
| 2. Heat damage of the powder | 2. Replace the powder | |
| 3. Film thickness too low | 3. Increase the thickness by raising the voltage or lengthen the spray time | |
| Pencil Hardness/Abrasion Resistance [poor] | 1. Under cured | 1. Increase dwell time or temp in oven |
| Penetration [Poor] | 1. Powder delivery | 1. Adjust powder delivery |
| 2. Poor ground | 2. Check ground | |
| 3. Improper spray pattern | 3. Select proper deflector or use suitable barrel and cover (consult equipment supplier) | |
| 4. Voltage too high or too low | 4. Adjust voltage settings so powder builds on pans edges and leading surfaces, do not repel pwoder from corner | |
| 5. Poor gun replacement | 5. Adjust gun position so powder cloud has a direct path to recess area | |
| Pinholing | 1. Coating thickness too low | 1. Incresae coating thickness by usinga higher voltage longer spray time, or more dense powder cloud |
| Sags | 1. Coating thickness too high | 1. Reduce coating thickness by using a lower voltage, shorer spray time, or less dense powder cloud |
| 2. Curing temp too low | 2. Increase oven temp | |
| Soft Surface | 1. Curing tempo too low | 1. Increase oven temp and/or time in oven |
| 2. Contamination with an incompatible powder, especially a thermoplastic | 2. Clean guns, hose, and hoppers, use virgin materials | |
Links in this section:
• epoxy polyester powder • epoxy powder • polyester powder
• speciality powder • why powder coatings? • household appliances
• automotive components • furniture • architectural • electrical
• metal pre-treatment • chromatising • iron phosphating • zinc phosphating
• chromate process • troubleshooting tips • material safety sheets
Coating Types:
• Epoxy Polyester Powder
• Epoxy Powder
• Polyester Powder
• Speciality Powder
Technical Sheets• Click here to download
