What are these small dimples and how to fix them

Epoxy/eps

While sanding noticed small dimples on my bottom fill coat, on the deck I did a fill coat just a few hours after I laminated it so it came out great no dimples there I did not even use additive F, but on the bottom as it was a day after I sanded everything 100grit, cleaned with acetone, then denatured alcohol and after evaporation I wiped the surface with a clean microfibre cloth also added additive F to the resin.
Should I bother fixing them?
If so what is the best way for that?
Sand it down and try to take away their gloss and then do another light coat?
Spray paint 2 coats of satin acrylic varnish and forget about them?

Hey! I noticed you use epoxy and acetone, not a good idea as acetone eats away on epoxy. Maybe that caused the dimples?! I say light sand ,clean without acetone, light layer fill coat to even it out. Keep us posted :slight_smile:

Hard to tell from the pic but they look small fisheyes. Caused by contamination causing the epoxy to run away from that area. Rough them up with a dremel, sandpaper, or scotchbrite pad, dab a little bit of resin in there (Can even use Poly UV cure to make it quick and easy), and sand. I’ve also heard of people filling them with superglue… Haven’t tried that myself.

Contamination for sure. Now you have to track down what in your process is causing it.

Well its either the acetone, the alcohol or the air compressor, but how to clean the lap properly without any of those?

Could be lots of things…even the mixing cups or your hands touching the board. When I was making epoxy boards the only thing I cleaned the boards with after sanding was Dawn dishwashing liquid and warm water and a scotch brite. Had one board do what you’ve got there because I picked up the board and put it under my arm to feel how it felt. It was obvious that simply touching my skin caused it as the separation was exactly where I’d touched it. Lesson learned. Other than repairs I’ve stopped using epoxy.

I’ve also had problems with small fisheyes/dimples since using epoxy even with a clean process (or so I thought). I saw Josh Martin talking abt successful hot coats with epoxy. He will squeegee on 3 oz of hot coat, pressing firmly into the weave, and with his hands applying it on the the rail to the tape. Wait 10-15 minutes then finish the rest of the hot coat as you normally would. I tried it and it seemed to help, not perfect but better for sure.

Something to do with better adhesion with that thin pre coat, to help eliminate fisheyes or off gassing or whatever causes those annoying imperfections.

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Most likely fisheyes from contamination or any other number of things on your hotcoat. To avoid this next time, pre-sand your deck and bottom before you hotcoat (not grinding anything down just giving a nice dusting and taking away any shine from the lamination). Next and most important, add surface agent to your hotcoat resin. The wax from the surface agent will bond your coat nicely and prevent fisheyes. You should be checking your hotcoat for a couple minutes after you perform it checking for little dimples and filling them with resin.