Powder Coating

Back ionization appears as rough, “stippled” patches or tiny craters when excessive charge builds on the part surface and repels incoming powder. It’s common on over-charged passes, thin edges, and recoat areas. To prevent it, BLUETEE recommends:
• Maintain solid earth ground (<1 MΩ) with clean hanging points; remove paint build on hooks.
• Use appropriate gun settings—lower kV and μA in close/inside corners and during recoats; increase flow/atomizing air only as needed.
• Keep 6–10 in (150–250 mm) gun-to-part distance and move at steady speed to avoid dwell.
• Apply lighter first coats and cross-coat for coverage; avoid piling powder in Faraday areas.
• Ensure booth air is dry and clean; control humidity; sieve reclaimed powder and maintain proper mix ratios.
• Verify cure schedule to avoid over-bake that can accent defects on recoats.
For affected parts, gently blow off loose powder, reduce kV, re-spray thin passes, or sand and recoat if cured. BLUETEE can provide outgas-forgiving powders and process tuning to deliver smooth, uniform films across complex geometries.