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4. Tried stringy particles from the paint sticking to the nozzle, or pimples on coated
surface
Possible causes
Solutions
(1) Too fast evaporating solvent
(1) Change to slower solvent or adjust with
(2) Higher viscosity of paint
(2) Lower the viscosity.
5. Pimples on coated surface
Possible causes
Solutions
(1) Poor atomization of paint
(1) See above 1.
(2) Dirt in the spray booth
(2) Provide filters at air exhaust and remove dirt
on the surface.
(3) Contaminated atomizing air
(3) Clean or replace filter on air control.
(4) Inferior pigment dispersion
(4) Change solvent or filter the paint.
6. Orange peel on the coated surface
Possible causes
Solutions
(1) Too high booth temperature or too
fast evaporating solvent
(1) Adjust the temperature or change to slower
solvent.
(2) Higher object temperature
(2) Adjust drying furnace temperature.
(3) Too fast air flow of booth exhaust
(3) Adjust to 0. 5 to 1.0 m/sec. flow at object
surface.
7. Crawling on coated surface
Possible causes
Solutions
(1) Insufficient cleaning of the surface
(1) Clean sufficiently or degrease the surface.
(2) Contaminated atomizing air
(2) Clean or replace filter in air control.
(3) Poor air exhaust in baking furnace
(3) Be sure there is sufficient air exhaust.
8. Sags & runs on coated surface
Possible causes
Solutions
(1) Too thick coated film
(1) Decrease paint output or move spray gun
faster.
(2) Too low paint viscosity
(2) Adjust to higher viscosity.
(3) Slow evaporation of solvent
(3) Change to faster solvent.
