1. What Is “Orange Peel” in Automotive Painting?
In automotive refinishing, “orange peel” refers to an uneven surface texture that develops after paint or clear coat is sprayed and dried, resembling the surface of an orange. This uneven texture reduces the smoothness and gloss of the paint finish, affecting the overall appearance and perceived quality of the vehicle.
2. What Causes Orange Peel?
2.1 Improper Spray Gun Pressure
If the spray gun pressure is too low, the paint may not atomize properly. Larger paint droplets can result, making it difficult for the coating to distribute evenly across the surface and increasing the risk of orange peel.
Solution: Adjust the spray gun pressure according to the paint manufacturer's recommended range.
2.2 Paint Viscosity Is Too High
When the paint viscosity is too high, its flow and leveling properties are reduced. As a result, the coating may not flow out properly after application, leading to an uneven surface texture.
Solution: Use the appropriate thinner or reducer to adjust the paint viscosity to the recommended spraying viscosity.
2.3 Incorrect Spray Distance and Speed
If the spray gun is held too far from the surface or moved too quickly, paint droplets may partially dry before reaching the panel. This prevents the coating from flowing and leveling properly.
Solution: Maintain the appropriate spray distance and gun speed. A typical spray distance is around 15 cm, helping ensure that the paint remains sufficiently wet when it reaches the surface and can flow out evenly.
2.4 Uneven or Excessively Fast Drying
If solvents evaporate too quickly or the spray booth temperature is too high, the surface of the coating may dry too quickly while the underlying layer has not yet leveled properly. This can result in an uneven surface.
Solution: Select the appropriate solvent and thinner combination, and control the temperature and humidity of the spraying environment.
2.5 Poor Surface Preparation
A rough, contaminated, or inadequately prepared substrate can also prevent the coating from flowing and adhering evenly, resulting in an orange peel texture.
Solution: Make sure the substrate is smooth, clean, and properly prepared. Sand and clean the surface when necessary.
2.6 Improper Equipment Setup or Calibration
Using an inappropriate spray nozzle, air cap, or fluid needle for the coating, or failing to properly set up and calibrate the spray gun, can also result in poor spray performance.
Solution: Select the appropriate spray equipment and components according to the type of coating, and regularly check and calibrate the spray gun.
2.7 Paint Formulation Issues
An incorrect ratio of hardener or additives, or incompatibility between different components, may also contribute to orange peel.
Solution: Strictly follow the paint manufacturer's recommended mixing ratios for hardeners, reducers, and other additives.
3. How Can Orange Peel Be Prevented After Spraying?
3.1 Adjust the Spray Gun Pressure
Make sure the spray gun pressure is within the range recommended by the paint manufacturer. Insufficient pressure can result in poor atomization, larger droplets, and an uneven coating.
Recommendation: Regularly check and calibrate the spray gun to ensure the correct spraying pressure.
3.2 Optimize Paint Viscosity
Paint viscosity that is too high or too low can affect the spraying and leveling performance. Adjust the reducer ratio according to the spraying environment, such as temperature and humidity, and the type of coating to achieve the appropriate application viscosity.
Recommendation: Use a viscosity cup to measure the paint viscosity and ensure it is within the recommended range.
3.3 Control Spray Distance and Gun Speed
Holding the spray gun too far from the panel or moving it too quickly can cause paint droplets to partially dry before reaching the surface, preventing proper flow and leveling.
Recommendation: Maintain a spray distance of approximately 15–20 cm from the surface and move the spray gun at a consistent and controlled speed.
3.4 Choose the Appropriate Spray Nozzle and Equipment
An incorrect nozzle size or air cap can also contribute to orange peel. Make sure the nozzle size is compatible with the coating to avoid excessive material application or poor atomization.
Recommendation: Select the appropriate spray gun configuration according to the coating type and viscosity, and use the nozzle size recommended by the coating manufacturer.
3.5 Control Environmental Conditions
Temperature and humidity have a significant impact on coating drying and leveling. Excessively high temperatures can cause the surface to dry too quickly, while unsuitable humidity levels may affect the coating's ability to flow and level properly.
Recommendation: Maintain a stable spray booth temperature of approximately 20–25°C and a relative humidity of around 50–70%.
3.6 Proper Surface Preparation
The substrate must be smooth, clean, and free from oil, dust, and other contaminants to ensure uniform coating adhesion and leveling.
Recommendation: Thoroughly clean the substrate before spraying and carry out the necessary sanding and dust removal.
3.7 Select the Appropriate Solvents and Additives
Different solvents have different evaporation rates, while additives can affect the flow, leveling, and drying characteristics of the coating. Improper selection or use of solvents and additives may contribute to orange peel.
Recommendation: Strictly follow the coating manufacturer's recommendations when selecting and using solvents, reducers, and additives.
3.8 Apply Multiple Coats and Allow Proper Flash‑Off Time
When applying multiple coats, each layer should be given sufficient flash‑off time. This helps prevent excessive solvent entrapment or uneven drying between coating layers.
Recommendation: Follow the manufacturer's recommended flash‑off time and avoid applying subsequent coats too quickly or waiting excessively long between coats.
3.9 Technical Training and Standardized Application Procedures
Proper spray technique and standardized application procedures are also essential for preventing orange peel.
Recommendation: Provide regular training for paint technicians to ensure correct spraying techniques and consistent application procedures.
By carefully controlling these factors, the risk of orange peel can be significantly reduced, resulting in a smoother and higher‑gloss automotive paint finish.
4. How Can Orange Peel Be Corrected After It Occurs?
When orange peel has already developed after spraying, the uneven surface texture can still be improved or removed through several corrective methods. The appropriate solution depends on the severity of the orange peel and the condition of the coating.
4.1 Polishing
Mild orange peel can sometimes be improved through polishing. Polishing helps smooth the surface and restore gloss.
Steps:
- Use fine‑grit sandpaper, such as 2000 grit or finer, to lightly sand the surface and remove minor surface irregularities.
- Use polishing compound and a polishing machine to refine the surface until the finish becomes smooth and glossy.
Precautions: Avoid excessive sanding or polishing, as this may damage the clear coat or underlying coating layers.
4.2 Sanding and Repainting
For more severe orange peel, sanding and repainting may be required to completely remove the uneven surface texture.
Steps:
- Sand the affected area with medium‑ to fine‑grit sandpaper, such as P800–P1500, until the surface is sufficiently smooth and level.
- Clean the sanded surface thoroughly to remove dust, oil, and other contaminants.
- Reapply one or more coats of paint or clear coat evenly, following the correct application procedure to prevent orange peel from recurring.
Precautions: Allow sufficient flash‑off time between coats and avoid excessive film build.
4.3 Spot Repair
If orange peel is limited to a small area, localized sanding and repainting can be performed instead of refinishing the entire panel.
Steps:
- Sand and clean the affected area.
- Reapply the same or compatible coating using the appropriate application technique, blending the repaired area smoothly into the surrounding finish.
Precautions: Ensure proper color matching with the surrounding area and use suitable blending techniques to achieve a seamless repair.
4.4 Using a Leveling Agent
Leveling agents can improve the flow and leveling properties of a coating and help reduce the risk of orange peel. In some coating systems, an appropriate leveling additive may be incorporated into a subsequent coat when permitted by the coating manufacturer's formulation guidelines.
Steps:
- Add the recommended amount of leveling agent to the coating used for the subsequent application.
- Reapply the coating using the appropriate spraying technique to improve surface leveling.
Precautions: The dosage of the leveling agent must be determined according to the coating system and the manufacturer's recommendations.
4.5 Combining Dry and Wet Sanding
For severe orange peel, dry sanding can first be used to remove major surface irregularities, followed by finer wet sanding to achieve a smoother finish.
Steps:
- Use dry sandpaper, such as P800, to level the coarse orange peel texture.
- Use wet sandpaper, such as P1500–P3000, for finer surface refinement.
- Clean the surface and proceed with polishing to restore the gloss.
Precautions: During wet sanding, avoid excessive pressure and heat buildup that could damage the clear coat.
4.6 Use High‑Quality Polishing Compounds and Tools
High‑quality polishing compounds and professional polishing tools can remove mild surface imperfections more efficiently and restore smoothness and gloss.
Recommendation: Select a polishing compound suitable for the coating system and use a professional polishing machine, such as a dual‑action (DA) polisher, for the finishing process.
The appropriate correction method depends on the severity of the orange peel. Mild orange peel may be improved through polishing and light sanding, while severe orange peel may require more extensive sanding and refinishing. Regardless of the method used, each step should be performed carefully to avoid introducing additional surface defects.
5. Choosing Parrot® Gloris Clear Coat Means More Than Choosing a Product – It Also Means Professional Technical Support
During automotive painting, defects such as sagging, orange peel, pinholes, whitening, and slow drying are not necessarily caused by the clear coat itself. Mixing ratios, spray gun settings, spray distance, film thickness, spray gun speed, and application conditions can all affect the final coating performance.
Therefore, for auto body shops and professional painters, choosing a clear coat is not only about its gloss, hardness, drying speed, and durability. The ability of the supplier to provide ongoing technical support is equally important.
Parrot® Gloris not only provides automotive refinishing clear coat products, but also provides product application support and technical guidance to our distributors, their downstream customers, and end users.
When customers encounter sagging or other application problems, we can work with them based on the specific product model, application process, spray gun settings, mixing ratio, and actual application conditions to help identify the possible causes and provide appropriate adjustment recommendations.
Our Technical Support Can Help Customers:
- Understand the correct product mixing ratios and application procedures
- Adjust application parameters according to different working conditions
- Optimize spray gun settings, spray distance, and spray gun movement speed
- Reduce common application defects such as sagging, orange peel, and pinholes
- Analyze actual application problems and provide practical technical solutions
- Provide product application support for distributors' downstream body shops and end users
