Bottom Paint?

[Kidgold]

This may be a dumb question. But, what different colored paint on the bottom of a boat for?

I am looking to buy a 2000 Sea Ray that was mostly used in salt water. It is white but has light blue paint on the bottom of the bottom. This looks really ugly when its on the trailer. So, if can't be for looks. Is there a purpose? Prevent barnacles? Confuse the dolphins? Camoflage from whales??

Kidding aside. I am just curious.

 

[fishmen111]

Re: Bottom Paint?

Two main reasons are to prevent anything from growing on the bottom and to minimize water intrusion. The paints usually have a copper and/or zinc base that limit organic growth. They also are effective at this by being sacrificial. The paint is intended to wear away over several years assistng the chemical base in preventing growth. Second, though you would think fiberglass is completely waterproof...it is not. The glass strands themselves are, however, the binders used to hold them together are not. Keep in mind that we are talking over very long periods of constant immersion here. The paint is a barrier to the gelcoat to help prevent blisters resulting from intrusion.