| DEFECT
/ PROBLEM |
CAUSE |
SOLUTION |
SAGGING
Paint drips in its application under vertical surfaces. |
|
- Low viscosity.
- Excess of coat.
- Excess of thinner.
- Low room temperature.
- Low pressure, excess of flow, proximity to the surface.
|
|
- Increase the viscosity by diluting less.
- Use a faster thinner.
- Increase the pressure, reduce the flow, move the spray
gun far of the surface. |
|
DRY
SPRAY
Due to the paint particles that reach the surface and
placed themselves as dust under the already formed film. |
|
- Thinners too volatile.
- High application pressure.
- Low flow with an excess of air.
- Too much distance between the spray gun and the surface. |
|
- Add a slower thinner.
- Decrease the pressure.
- Increase the flow of the paint.
- Application closest to the surface. |
|
BLOOMING
Lack of clearness in the gloss, opacity, produced by the
fast evaporation of the thinner. The surface become colder
with the result of a condensation of the ambient humidity. |
|
- High ambient humidity.
- Thinner or damping. |
|
- Do not paint if it is higher than 80 %.
- Use faster thinners. |
|
MIXING
RATIO
Division of pigments, appearing spots and strias in different
thickness of the coat. |
|
- The thinner is not adequate for that paint.
- Excess of dilution or lack of homogenisation. |
|
- Use the thinner recommended by the manufacturer.
- Dilute correctly under agitation. |
|
PAINT
DEFECT
Superficial defect produced by lack of humidity in the
surface or in the base coat. Its visibility will be in
terms of the superficial tension. |
|
- Incorrect degrease of the surface.
- Atmosphere contaminated by silicones.
- Water or oil in the compressed air.
- Spray gun and hoses not cleaned. |
|
- Degrease and remove any rust from the surface with an
adequate thinner and clean dusters.
- Add antisilicones.
- Purge and filtration of the air.
- Proper cleanness of the equipment. |
|
BOILING
AND BUBBLING
Occurs in case of a breaking or a deformation of the painted
surface, when it dries so quickly than the thinner not
evaporated tries to come out . |
|
- Very fast thinners.
- High room temperature.
- Excess of paint agitation. |
|
- Add a slower thinner with an equilibrated evaporation.
Use the recommended hardener and thinner.
- Apply thinner coats with wide intervals.
- Leave the diluted mixture settle for some time before
starting the application. |
|
ORANGE
PEEL
Surface not well levelled, orange peel. |
|
- High viscosity for the application.
- High pressure for the application.
- Very fast thinners.
- Base coats not enough dry. |
|
- Reduce the viscosity by diluting more.
- Reduce the air pressure.
- Add a heavy thinner.
- Leave the base coat to dry correctly. |
|
LACK
OF DRYING
The time between the application and the manipulation
is too short as regards the recommendations. |
|
- Low room temperature or high ambient humidity.
- Slow thinners.
- Coats too thick.
- Old paints of oxidative drying.
- Incorrect dosage of the hardener in case of 2k product
s. |
|
- Painting place with room temperature and no humidity.
- Use the recommended thinner.
- Control the applied coat.
- Addition of drier.
- Respect the proportions of the mixture. |
|
LACK
OF ADHESION
When the dry film come off easily from the surface or
the precedent coat. |
|
- Incorrect surface preparation: grease, humidity.
- Base coats in bad conditions.
- Poor sanding.
- Incorrect selection of the application system. |
|
- Proper surface cleanness and preparation.
- Degrease, remove any rust and sand the surface.
- Consult the manufacturer for the adequate application
system. |
|
