"Faraday Cage Effect" is the electrostatic force that prevents charged particles from penetrating into recessed areas. The charged paint particles are attracted to the closest grounded surface, as shown in Figure 1. 

Limitations due to an electrostatic painting system might make it impossible to achieve minimum recommended dry film thickness on all areas of an extrusion.  Areas subject to the Faraday Cage Effect are inside corners, see Figure 2, and recessed areas such as channels and cavities. 

Linetec follows the criteria listed below to define the acceptable quality level resulting from the Faraday Cage Effect: 

·               • Recess depth is from 50% to 100% of the width

o        There will be color coverage within the recess, but less than the specified dry film thickness. 

·               • Recess depth is from 100% to 200% of the width

o        Paint will be present, but the substrate may show through in some areas.

o        The deeper the recess, the lighter the coverage will be within the recess.

o        The substrate exposure will be less noticeable on pastel and light colors, and most noticeable on dark colors. 

·               • Recess depth is greater than 200% of the width

o        There may be no paint coverage at the bottom of the recess.