Should I be able to see through my fiberglass?

[fjordstar]

I climbed down into the bilge yesterday to do some more scrubbing when I noticed the sunlight glowing through parts of the hull. Is that normal??









One the second pic, there are two pinholes that I can't even see from the outside. But they're barely above the waterline on a calm day. I've never seen water in the aft part of the bilge but they still make me nervous. What's the best way to fix a small hole like that!





Then I flipped around heading down the starboard side up to the bulkhead(?). Found some water in there which explains the squishy sound we here when we walk on the cabin floor. The wood is rotting. Is this something that needs to be totally replaced or should I just try it out and leave it in place?

 

[watercolors II]

Gelcoat and wood

Fiberglass resin is very transparent and with the glass strands in it they themselves become invisible except for the surface texture you so often see. Gelcoat is more opaque depending on the color so that white would let the most light through and black would let the least.

Gelcoat is sprayed onto the mold first and then the resin and cloth is added on top of the gelcoat. In areas that would be seen very easily the mfg. would spray an additional coat of black gelcoat over the white gelcoat before adding the cloth to help block the light coming through the light colored gelcoat. In areas not seen, that would add labor and cost to the project when not needed.

In your previous post you ask the question about the gelcoat, what you’re seeing is where the gelcoat has been rubbed, scrubbed and deteriorated to the point where it is almost gone. You can replace the gelcoat but, it is not like paint where paint will flow and level much smoother than gelcoat and is much easier to work with.

The wood is added to fiberglass to add tremendous strength to that area. These areas of rotting wood must be addressed first and foremost, the thin gelcoat is only cosmetic.

Good luck!

 

[Kemo Sabe]

Those two small holes can be filled with one of those small tubes of gelcoat available from a marine supplier. It'll harden, and it'll be easy to sand from the outside to make a smooth surface. I accidentally bored a drill hole through the hull from the inside, port v berth, above the waterline and that's what I used.

 

[centerline]

some builders will paint the inside of the hull and/or deck with a flat black paint before assembly to prevent light transmission thru it..... it isnt any thicker, but because you dont see the light shining thru it you may think it is...