Gelcoat or paint?

[D-Squared]

A friend of mine has a little 17' MacGregor in need of a lot of work. He's going to let us use it for free and all of us are going to do some repairs and painting in time for the sailing season.


It is white with a blue hull, but we can't quite determine what is peeling and oxidizing paint and what is peeling gelcoat (is there such a thing?) If it's blue that rubs off on your fingers, is that just paint? There is what looks like peeling clear stuff on TOP of the oxidized. Is that the gelcoat?


The owner wants to sand it down to "white". Will that take us past the gelcoat? Advice, please!!!!

[Uncle Bob]

Originally Posted by D-Squared

A friend of mine has a little 17' MacGregor in need of a lot of work. He's going to let us use it for free and all of us are going to do some repairs and painting in time for the sailing season.


It is white with a blue hull, but we can't quite determine what is peeling and oxidizing paint and what is peeling gelcoat (is there such a thing?) If it's blue that rubs off on your fingers, is that just paint? There is what looks like peeling clear stuff on TOP of the oxidized. Is that the gelcoat?


The owner wants to sand it down to "white". Will that take us past the gelcoat? Advice, please!!!!

Paint peels, gelcoat doesn't. If the blue is chalking and peeling it is paint, if it is just chalking with what appears to be a clear coat in patches over it it may be a degrading blue gelcoat, that someone previously sprayed a clear coat over to improve the look of it.
If you do rub it right back then it will require a repaint, sprayed or roll and tip with a decent quality paint appropriate to the vessel and bank balance.

[D-Squared]

Thank you for the quick reply! My guess is we'll repaint. Is there a danger of sanding too deeply, into the gelcoat?

[D-Squared]

.....and how do I know I'm in the gelcoat????

[thomm225]

Does picture this help? I sanded off the peeling paint on my boat down to the beige gelcoat. I did the entire topside hull until it was all beige 40 year old gelcoat then repainted.

I was only planning to do a bottom job but the topside white paint was peeling so bad I had to do something about it. This in 2014.

[D-Squared]

Yes, it does! Thanks.

[Sailmonkey]

Gelcoat can be just about any color of the rainbow. Don’t go sanding looking for blue or white or beige!

If you sand through the gelcoat you’ll see fiberglass, stop sanding there!

[D-Squared]

I think our plan is to buff off the bad paint. No sanding just yet, maybe never. One step at a time! Thanks.