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9. Poor hiding film
Possible causes
Solutions
(1) Insufficient paint output
(1) Adjust paint output, move gun faster and
consider overlapping spray.
(2) Too low paint viscosity
(2) Adjust the viscosity.
10. Pinholes on coated surface
Possible causes
Solutions
(1) Contaminated atomizing air
(1) Clean or replace filter in air control.
(2) Faster evaporating solvent
(2) Change to slower solvent.
(3) Higher object temperature
(3) Lower the temperature.
(4) Insufficient drying of undercoat
(4) Make sufficient drying.
(5) Too short setting time
(5) Take sufficient setting time
11. Blushing on coated surface
Possible causes
Solutions
(1) Higher temperature and humidity
inside and outside of booth
(1) Use slow evaporating solvent or check air
conditioning system.
(2) Inadequate selection of solvent
(2) Consult material supplier.
12. Bubbles on coated surface
Possible causes
Solutions
(1) Contaminated atomizing air
(1) Clean or replace filter in air control.
(2) Insufficient drying after water
Grinding
(2) Make sufficient drying.
(3) Too thick film build
(3) Lower paint output.
(4) Faster evaporating solvent
(4) Change to slower solvent.
(5) Higher drying furnace temperature
(5) Adjust the temperature.
13. Unfavorable pattern shaping
Possible causes
Solutions
(1) Paint or dust sticking at air and paint
outlets on the nozzle
(1) Thoroughly clean the nozzle with solvent and
a bamboo brush, and filter the paint.
(2) Higher viscosity of paint
(2) Lower the viscosity.
(3) Damaged front end of the nozzle
(3) Repair or replace the nozzle.
(4) Mis-adjusting of pattern air
(On flat spray nozzle only)
(4) Correctly by pattern adjusting knob.
(5) Failed nozzle assembling
(5) Check and tighten material nozzle and fix air
cap