The manual (in the link
https://sbo.sailboatowners.com/downloads/Catalina_Capri-22_44729875.pdf) indicates:
1. Page 41 - Most fiberglass boats are manufactured of two "layers" of material, permanently bonded together by a chemical reaction. The outside surface is formed by a colored gel coat. This is a special resin material containing concentrated color. It provides a smooth, finished surface. The second "layer" is made up of
polyester resin reinforced with laminations of fiberglass mat, cloth, or woven roving. Both the gel coat and
polyester resin are "cured" by a chemical catalyst that causes them to form a hard, strong mass that is highly resistant to impact and damage.
2. Page 43 - The bottom may be prepared for painting using conventional dewaxing solvents, then sanding the gel coat surface or using a chemical etching type primer. The keel has been painted using epoxy primer, filler-fairing compound and finished with epoxy paint.
The threads below discuss the merits of epoxy coating and the risk of blisters and whether you need antifouling paint. My 2 cents .............. if you plan to keep the boat in the water for any extended period of time that you should epoxy coat the bottom to mitigate water intrusion into the fiberglass and blisters and apply antifouling paint to mitigate barnacles in salt water and zebra mussels in fresh water adhering to the bottom and eating through to the fiberglass and algae, which creates drag and slows the boat down.
I am in the early stages of preparing to paint my 81 Cat22 for the upcoming season. Right now it has some type of antifouling paint that stays on your hand when you rub it or anything else it touches not to mention it kinda looks like broken egg shell in places. This makes for a less than smooth...
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