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Powder Coating Application: Overcoming The Faraday Cage Effect
The "Faraday cage effect" occurs when the inner recesses and corners of a charged substrate do not have a charge, and the charged powder particles create resistance, making it difficult to coat these areas. There are ways to overcome the Faraday cage effect and better coat inner corners and odd part geometries.
Overcoming the obstacles of the electrostatic process:
Blast powder into recesses
Increase the powder flow rate
Maximize the gun to part distance
Use slotted tip to concentrate the spray
These methods can use excess powder, have higher film thicknesses than desired, and could result in an uneven film build.
Using the electrostatic process:
Finesse the powder into recesses
Decrease powder gun flow rates
Reduce gun voltage to 40-60 Kv
Maintain gun to part distance of about 8-10 inches
Use slotted tip to concentrate spray
Approach recess at an obtuse angle
These methods could result in a slower application time.
Spraying in the Faraday Cage: spraying at the recesses of a part at an obtuse angle can help to apply the coating properly.
Reduces air turbulence
Allows deeper penetration
Minimizes early back ionization
Utilizes more lines of force
The "Faraday cage effect" occurs when the inner recesses and corners of a charged substrate do not have a charge, and the charged powder particles create resistance, making it difficult to coat these areas. There are ways to overcome the Faraday cage effect and better coat inner corners and odd part geometries.
Overcoming the obstacles of the electrostatic process:
Blast powder into recesses
Increase the powder flow rate
Maximize the gun to part distance
Use slotted tip to concentrate the spray
These methods can use excess powder, have higher film thicknesses than desired, and could result in an uneven film build.
Using the electrostatic process:
Finesse the powder into recesses
Decrease powder gun flow rates
Reduce gun voltage to 40-60 Kv
Maintain gun to part distance of about 8-10 inches
Use slotted tip to concentrate spray
Approach recess at an obtuse angle
These methods could result in a slower application time.
Spraying in the Faraday Cage: spraying at the recesses of a part at an obtuse angle can help to apply the coating properly.
Reduces air turbulence
Allows deeper penetration
Minimizes early back ionization
Utilizes more lines of force