Elevations of differing size in the powder coat, no adhesion due to enclosures at the part surface
Water on substrate
Check dryer and hanging configuration
Corrosion, oil and grease residues
Optimise pre-treatment
Salt residues or chemical remnant on part. Sometimes evident as a fine raised ring.
Check pre-treatment final rinse stage. Demineralised water is recommended, particularly in hard water areas.
We can make any powder coating colour or finish to order so get in touch to discuss your requirements.