Paint Manual - Dove-Medows Marine Coatings Ltd

Troubleshooting
The most common causes of failures: poor surface preparation
and cleaning; too smooth surface; moist surface; wood with
high moisture content; insufficient priming; missed coating
intervals.
Fault
Application marks
Blistering – small
swollen areas,
surface may feel like
sandpaper to touch
Blushing – white
milky appearance
on film
Chalking – poor
gloss, powdery
surface
Cracking/Crazing
– appearance of
shattered glass
Causes
Wrong application tools.
Temperature too hot, causing
paint to cure too quickly and
not allowing the product to flow
naturally.
Temperature too cold, making
the product too thick and difficult
to distribute evenly.
Surface contamination before
paint application.
Solvent entrapment due to paint
being applied too thickly or
overcoated too soon.
Moisture entrapment during
coating.
Paint applied when humidity
was too high.
High humidity can cause the
thinners to evaporate too fast.
Water condenses on the
relatively cold surface and the
subsequent moisture creates
blushing.
Prolonged exposure to
Ultra Violet rays.
Poorly mixed paint.
Extreme temperature changes
during paint.
Incompatible overcoating.
Paint applied too thickly or
overcoated too soon.
What to do
Abrade back to flat even surface
and refinish, considering
application tools and conditions.
Check for any other areas that
may have a similar problem,
abrade back all blisters, fill where
necessary and recoat
Abrade back until blushing is
cleared, and recoat considering
the relative humidity and
temperature.
For a permanent cure, abrade
back and recoat ensuring the
paint is properly mixed.
Abrading back and repainting
may cure this. However it’s
more likely the complete coating
needs to be removed and an
appropriate coating applied, in
accordance with recommended
specification.
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Troubleshooting