Field lines from the gun end on the closest, most prominent grounded surfaces, so the lips of a channel or the outer wires of a basket catch powder while the inside corner stays thin or bare. Fixes include lowering kV, spraying recesses first, moving the gun closer, changing the nozzle or using a tribo gun.
Inside corners on the cabinet are bare, classic Faraday cage, spray them first at low kV then do the faces.
Pushing more powder and more kV into a Faraday area makes it worse, because the edges just grab more.
Also heard as
- Faraday cage
- Faraday effect
Related terms
Cage
Shop shorthand for a recess resisting powder because of Faraday cage effect.
Tribo gun
A powder gun that charges particles by rubbing them against a plastic tube, with no high-voltage electrode.
Free ions
Charged air molecules from a corona electrode that never attach to powder but still land on the part.
kV
Kilovolts, the voltage setting on a corona gun that governs how hard it charges the powder.
Holiday
A skip, void or pinhole in the coating where bare metal is exposed.