My neighbor just bought a small boat and wants to remove the bottom paint. The previous owner left it in salt water for a long time and looks like it has about 4 layers of paint on it... some of it is chipping. Anyway, it look really bad and he wants it removed.

What's the best way to remove it? I suggested pressure washing as much as possible off and then trying Zip Strip. I assume you shouldn't sand this crap down because of the toxicity, correct? Any other ideas?


TIA!

soda blast it

Yeah. Soda blast or walnut shell blast.
There are also strippers made for bottom paint, but it matters what kind of paint (ablative or hard).

Typical paint strippers will melt the gelcoat since it is essentially a vinyl based plastic.

Sanding is effective, but will leave the underlying gelcoat heavily scuffed. However, chances are that the gelcoat was scuffed initially to prep it for the paint so you won't be adding that much to it. But you need to be sure you don't scuff THRU the gelcoat. It's all give and take.

As far as environmental stuff, he should sand over a tarp so when finished he can bundle it, bag it, and trash it properly instead of hosing it into the yard. Good breathing filtration is also essential.

Best of luck.

Soda blasting doesn't sound like a DIY at home project, so I don't think that's an option.

Using an orbital sander would probably work well, but health safety is a big concern (as I would be helping). What is needed for filtration? I assume a 3M dust mask wouldn't cut it.

Chemical stripping sound like the best choice. I don't know jack about bottom paints, how can I tell if it's ablative or hard? How well do these work?



BTW, we are not worried about scuffing the gel coat, it will be repainted with some type of two part epoxy to make it look nice.

Kleen Strip makes a fiberglass paint stripper that works great but it won't remove epoxy primer. Had to sand that off.

I'll look into that, thanks.

I know we can scrape some of it off so we'll do as much as possible with the scrapper. Wet sanding is a great idea for the leftover areas which are left from the scrapping and chem treatments.

Does that work on bottom paint???

don't know about cleaning bottom paint, but it damn sure cleans nearly evverything else on the planet.

I tried it, doesn't work.
Ended up with very clean old bottom paint still on the boat.