I have another question about polyurethane paint. After priming the
epoxy and using a poly paint would it be lighter in weight than gel
coat finish and more fade resistant. The weight issue is important
because I'm using it on a canoe.
wrote:
Flase.

Both one and two part polyurethanes are great finishes over epoxy
substrates *provided* there is no remaining 'amine blush.'
Manufacturers of PU (like Interlux) have all developed a 'tie coat' or
'primer' to isolate the epoxy sustrate from the overcoating paint.
Here's what Interlux says:

"Be sure to use Epoxy Barrier-Kote 404/414 over clear epoxy to prevent
blush from affecting drying and adhesion of Brightside".

MW