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Default Epoxy blush stragtegy

Patrick:

I think you're confusing 'blush' with "water in or on the epoxy before
it's cured". In my experience, amine "blush" - a tacky, waxy feel to
the surface of a *cured* epoxy surface, is easily removed with warm
water and a scotch-brite pad, a nylon scrub brush, or any other
"kitchen and bath" cleaning appliance (and a little elbow grease). The
key ingrdiant is water, as the 'blush' is water soluable. With most of
the epoxies I've used, this scubbing action causes a light, white
'foaming' of the surface being scrubbed which one then wipes off with
an absorbent towel. An easy, low effort task.

On the other hand, when working over large epoxy layups - especially in
the summer months - I often can't keep (despite my best efforts) sweat
from dropping off my brow onto the fresh epoxy/glass surface. One can
easily see these sweat bombs, as the area where they land turns white,
and no ammount of additional epoxy slathered onto the "sweat spot" will
cause it to vanish. One or two of these in a large layup is NBD, but
if the entire surface of your project got wet, I think you're hosed.
My sense is that, in this uncured state, the water dilutes the amine
'hardner' in the epoxy matrix; recall that all epoxies consist of two
parts: Resin (not water soluable) and hardner (definately water
soluable). Hence, the rain on your uncured epoxy disrupted the
chemical properties of your epoxy system, and no ammount of praying
will fix it.

Time to get out the grinder, and invest in a tarp...

Mike Worrall
Los Angeles