I am posting under "Darkroom" because the same info would apply to a fiberglass sink. I have built fiberglass over wood sinks in the past with no problems but I just built several water/dust proof boxes to take film holders to the field with a fiberglass lining. The problem is that after 4 days to cure I still have some spots with a sticky film. I don't think the resin and hardener were mixed well. The bulk of the resin is solid just sticky on the surface.
Can I clean up the uncured resin with acetone with damageing the hard resin or is there a better solution?