Despite having made boards since 1975 I still get sand throughs, mostly around fins. Sometimes I do gloss coats using rattle can acrylic, brush on urethane or, my favorite, wiping on about 2 oz epoxy with a rag (this technique mostly to seal sand throughs not so much for gloss).
However sometimes, many months or even years later the sand throughs reappear (see photo).
Any ideas how to address these without having to add another coat of anything?
ps I glass with epoxy.
Rub a little catylist on it then a wipe with Behr low luster concrete sealer and a light wet sand a couple days later. That’s what I do if its minor. Styrene will do something similar. Something like you’ve got in the picture I’d probably coat with thinned resin.
Edit: Just saw you are doing epoxy. You could try xylene and then spray clearcoat or the previously mentioned sealer.
Thanks Mako. Xylene plus concrete sealer? Or xylene with thinned epoxy? Can you thin epoxy with xylene?
I would use Upol clear automotive spray you can get it on amazon gloss or flat/satin very durable just spray and done .
Yes you can thin epoxy with xylen.
Are you sure it’s sand through or some kind of interfiber delam from over stress?
Does it disappear when you wet with alcool?
I had that with some glass like aerialite white. Nothing make it disappear but stay strong. Switch to glass with 970 clear finish, no more problem…
