After application and during the curing process,
epoxy resin releases a wax-like’ film onto the surface called ‘Amine Blush’.
This amine blush will prevent subsequent layers
of epoxy and other products fully adhering unless removed properly.
The best way to reduce blushing is to work
in warm temperatures (the epoxy sets up fast, reducing the blush window) and
with humidity at low levels.
It would be best to avoid conditions where
moisture is coming out of the air as temperatures fall.
Amine blush is water soluble so, thoroughly
washing the cured epoxy with clean warm water, soap, and a stiff brush or
Scotch-Brite™ pad is the only way to completely remove it.
Sanding before removing the amine blush may
sand the blush deeper into the surface making it much harder to remove.
Even those products labelled as ‘amine
blush free’ or ‘no blush formula’ are best washed.
Solvents like Acetone will not remove the
If there is a good reason not to get your
project wet, you can use West System’s “Peel Ply”.
Peel ply is a finely woven nylon fabric
that will not bond to epoxy, however, the amine blush forms on the peel ply,
not on your cured epoxy.
Simply follow the instructions to apply
peel ply, ensure that the peel ply is thoroughly wetted out, let your epoxy
cure and then remove the peel ply once cured and before applying the next
coating, the blush will have formed on the peel ply not on the epoxy below.
Another advantage to using peel ply is that
it’s fine woven pattern is impressed into the epoxy coating, creating a ready
to bond to, graded, textured surface.
I am perfectly aware that the majority of Wooden Boat aficionados are sensible folk. However, I need to point out that I am an amateur wooden boat enthusiast simply writing in order to try to help other amateur wooden boat enthusiasts. And while I take every care to ensure that the information in DIY Wood Boat.com is correct, anyone acting on the information on this website does so at their own risk.