Uneven gelcoat below the waterline.

[Yannis]

Many times when I see a hull below the waterline there are some places with uneven surface. To be more precise I am posting an image with a red arrow indicating the uneven surface I am talking about. Does anyone know what causes it. Any opinions and help will be appreciated!!

 

[slawosz]

Oh my, I will be first to reply!
I guess its old antifauling, not removed. Sometimes people paint layers after layers, in some places it goes away, it some doesn't.

 

[Tranona]

Yes, not the gel coat but layers of antifouling. The only way to get it smooth is to remove all the coating , preferably by blasting, back to the gel coat and start again. If you find there are imperfections in the gel coat you can fill and fair with epoxy to get a clean smooth surface. worthwhile then considering recoating with epoxy and a more long lasting antifoul such as Coppercoat.

 

[ryanroberts]

Been there, got it blasted and then spent 2 months under the boat having fun with epoxy. I would just ignore it and go sailing

 

[Stemar]

Go sailing.

However, if it bothers you, the rest of the antifoul looks in reasonable condition and there isn't any obvious blistering, so I don't think you need to take the hull back to the gelcoat, which is letting yourself in for a lot of expense and work. I reckon you could just wet sand the lumps smooth and put this year's dose of barnacle feed antifouling on.