Edge build-up in powder coating: identifying and eliminating causes
Excessive edge build-up in powder coating can lead to uneven layer thicknesses and visual defects. This phenomenon often occurs when too much powder adheres to the edges of the workpiece. Below, we explain the most common causes and provide practical solutions based on GEMA recommendations.
1. Powder cloud too large
A powder cloud that is too wide or dense can cause excessive powder to accumulate on the edges of the workpiece.
Solution: Work with a targeted jet and use the correct type of nozzle to optimally control the powder cloud.
2. Too much distance between objects
If the distances between the objects to be coated are too large, this can lead to uneven powder distribution and edge build-up.
Solution: Use gap control to optimise the distances between the objects and ensure an even coating.
3. Shape of the object
Certain object shapes can promote edge build-up, especially with sharp edges or complex geometries.
Solution: Work with PPC mode (Precise Powder Control) and use the SuperCorona® ring to precisely control the powder charge and minimise edge build-up.
By observing these points and regularly maintaining your equipment, you can increase the efficiency of your powder coating processes and avoid quality problems.
