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Re: Epoxy: application problem

I sanded the entire inside of the hull with 120 grit sandpaper to even out a previous coat that was uneven. That coat was applied a week or more prior. After sanding, I scrubbed with a grey scotchbrite pad and water, no soap. I vacuumed the dust, wiped with a damp paper towel then a dry paper towel to remove remaining dust. I mixed small batches (no more then 5 pumps each) and mixed thoroughly in a cup. I poured the epoxy into a roller pan and rolled it on with a foam roller working in about 2' sections, tipping off with a foam brush. Once I had the entire surface coated I looked it all over to be sure everything was covered. I was working in an open garage on an 80F+ day.

If you were wetting out the glass at 80˚+ you should have used a slow hardener. You don't mention this, did you yes or no? Even with small batches (you said 5 pumps of each which would be a huge batch!) and medium hardener I would expect the resin to set-up very fast at 80˚+.

From your description it sounds like you are following some of my suggestions on fiberglassing.

I only do a seal coat before glass wet-out on the exterior surfaces to ensure a transparent lay-up.

On interior surfaces I do a one step, bare wood and glass wet-out. These surfaces will not be seen so transparency is not an issue.

If you applied a seal coat a week prior to sanding you could have amine blush issues. Epoxy surfaces should be washed prior to sanding so contaminates aren't spread by sanding.

I agree with Nick, I can't see suggestions of contamination.

What I see is excess resin. It looks like you did not remove excess resin by going over the fiberglass with a squeegee to remove excess resin. If you did, your surface would have a uniform mat look. If you tried to remove excess resin with a squeegee but couldn't, your hardener was too fast and your batch too large

What you most likely have is fiberglass which have floated on top of the resin resulting in a irregular surface.

I didn't know about squeegeeing off excess resin when I built my first stripper canoe and I had a rippled surface.

The resin goes right through the glass which takes longer to absorb the resin and this means the glass has air in the fibers which floats the glass on top of resin, unless you squeegee off excess resin while it is still thin. The inside of the hull is just a big bowl and if you don't squeegee often (before you wet-out the entire hull interior) the resin will thicken to the point where it will not allow you to push the excess out of the weave with the squeegee.

I squeegee excess resin from my hull interiors during wet-out of the glass with every third of the hull coated. AND I use all the methods available to keep resin thin so it doesn't get trapped in the cloth.

See this video -