What to Do When Particles Appear in a Water-based Paint Film

During application, particles - bump-like protrusions like heat rash, rough to the touch - sometimes appear. Causes: 1) poor metal pretreatment - dust or sand left after sanding not cleaned before spraying; 2) bubbles from diluting with pure water not dissipated before application, especially in cold weather, leaving a rough surface after drying; 3) dust/sand in the spray environment or landing on the wet film; 4) overspray polluting the film; 5) incorrect use of water-based curing agent causing incompatibility, or insufficient stirring/filtering. Solutions: 1) fill uneven areas with putty, sand smooth and wipe clean before painting; 2) let mixed paint stand 10-20 min for bubbles to disperse; 3) filter diluted paint through cloth to remove debris, avoid windy/dusty weather and protect fresh work from secondary contamination; 4) correct spraying technique to avoid overspray; 5) match paint and curing agent compatibly, mix by ratio and stir well. For an already rough surface, sand smooth and apply another coat; for high-end decoration, sand or use polishing compound then finishing wax.