Originally Posted by Erin
Nothing to worry about IMV. Fibreglass is somewhat translucent, including gelcoat to a degree. The gelcoat is only a UV protector to limit degradation of the fibreglass and provide a pretty finish. 1mm thick should be quite acceptable I would have thought, as it doesn't provide any real structural benefit.
Agreed. Nothing to worry about. The lay up resin is clear. I was told that pigments, which would make it opaque, tend also to make it slightly porous and so are avoided. Gel coat is relatively brittle and if too thick will tend to crack or craze.