Bottom Painting Question

[Gary G]

My Luhrs MY was hauled today for winter storage. This was the first opportunity I had to see what the bottom looked like since it was in the water when I bought it last June. The bottom was power washed and seemed clean with no blisters. There were a dozen or so two by three inch areas on the hull where the bottom paint was nonexsistant. The fiberglass was exposed. It was solid with no fiber strands present but rough to the touch. There was no slime or sea creatures clinging to these areas but I would have thought that the fiberglass would have been like glass. Is that smooth top coat of glass removed so that bottom paint can be applied? What do you think?
Gary G

[witeagle]

the bottom of the hull where painted is sanded with 80 grit before paint is applied to give the surface some stickyness.

How thick is the rest of the paint around the areas that chipped away?

[Gary G]

the bottom of the hull where painted is sanded with 80 grit before paint is applied to give the surface some stickyness.

How thick is the rest of the paint around the areas that chipped away?
I always sanded the bottom of my old boat with 80 grit prior to painting the bottom, but I never saw areas like this where she's right down to the rough glass. I used to paint the bottom three or four times before I had to strip it all off to repaint. I'd guess that the thickness of this bottom paint is one or two applications, maybe 1/32nd. of an inch or less thick.
Gary