TOPIC: Black layer under gelcoat

When I strip off the gelcoat off the Seaflite hardtop, there is the outer white layer, then a layer of black and then the raw fiberglass. What is the black layer and what is its purpose?

Here's a pic

Last week I pulled the tarp off the MR to get started. It had been tarped for a year. Everywhere the tarp covered was black with mold. I powerwashed and the water coming off was like milk. Thought I got the old white paint off before. As the white came off spots of black started to appear, some areas the cloth started to show thru. The black layer looks like the same stuff they used to coat the inside, like a vinyl product. I was thinking it might be for sealing the glass, maybe this MR was not gel coated?

Anybody know?

It looks like the white Gel coat was backed up with black gel coat. it is a way for the person rolling the air out of the glass, to see the air. You can't see air to well in the glass laminate laid against white gel coat. but with a dark color the air showes up better.

Many use a layer of black backer Gel coat to prevent translucency in glass parts that will be viewed from both sides. If a hardtop is a single skin with semi-finished underside, the sunlight could highlight the thinner/thicker areas. The same effect is very apparent when crawling under the bow of most any boat. Even with another layer of white on the inner surface, the sun could be visible without a light blocker.

Greg

Slo-mo, I think you hit the nail on the head. Now that it is stripped off, I can see the supports underneath. Have to look into that when I get to the finish.

Now that you guy's mention I heard about the bubbles and see-thru on Ship Shape a couple months ago. My memory is fading fast.