Paint removal without damaging gelcoat

[Greg17955]

Hi everyone,

my first post but I've used this site for gathering knowledge for the last four years or more.
I own an O'Day 30 and scraped off 30 years of antifouling last year. This year I want to bring the topsides back to it's original condition following Maine Sail's "Tips for a great Buff wax"

Started on the transom with 600 grit wet & dry, then the port side, both came up great. When I started on the starboard side I discovered the previous owner (or someone else) had painted the whole side to cover up a very bad repair job. They used black car body filler. I scraped off the paint covering the repair with a paint scraper, this took about two hours and I was very careful. It covers about a 2ft square. After removing the paint the original gelcoat looks great so I'd like to remove it all. Plus the painted starboard side is a totally different colour to the port side and I'd never noticed it before.

I plan to get a professional to repair the previous repair and match the gelcoat colour, then finish restoring the topsides following Maine Sails advice.

What I need to know is - does anyone know how I can remove an unknown brand of paint from my gelcoat without damaging it. I estimate there's about 90 square feet of paint to remove.

Anyone had a similar problem or any advice to give
Thanks in advance
Greg

 

[KD3PC]

I would pick a tough spot and start with the less aggressive solvent and move towards a more aggressive one. perhaps start with some oven cleaner and see if the paint softens, if not then some acetone, then MEK, then some laquer thinner, paint solvents, then some of the more aggressive "paint remover" types. I would make sure to use clean rags for each test, unless you know which will not react.

You may get lucky and find that they used some cheap enamel auto paint...and the solvents work.

The only way to remove the paint without damaging the gelcoat is to walnut shell/soda blast or a very subtle composite blast. But that is best done by a pro..

best of luck

 

[tommays]

Really carefull razor blade IF it is not well stuck onto the gelcoat

Interlux Briteside one part sure did NOT give up easy as they preped it pretty good

 

[RichH]

Most 'topside' paints usually are easily 'lifted' when soaked in water for long periods of time; this includes 'catalyzed' or 2-part paints. The water migrates through the 'paint' to the gelcoat surface and under long term 'soak' the paint will lose adhesion to the subsurface. If you have access to shrinkwrap or plastic sheeting consider to overlay the paint with a thick layer of absorbent toweling/paper, then the shrinkwrap over top of the applied 'paper', etc., seal the edges of the plastic, thoroughly wet the paper (a little added 'caustic' will probably help the destruction .... but not the gelcoat), and long term 'soak it' ... weeks, etc. You may need to 'refresh' the amount of soak water from time to time under the plastic.

It may not remove 'all' the paint but will certainly reduce the adhesion making it easier to 'finish sand' the area.

 

[AtlanticAl]

I have been looking into this myself. I want to strip the really bad paint job the previous owner did to my boat, and try to polish up the original gel coat. I havent tried any paint stripper on it but i have heard people say Citri strip does not damage the gel coat, seems most other paint strippers, make the gel coat go soft. I intend to try it out, but havent got any right now.

 

[Cayennita]

It was said above, Soda blasting will remove all the paint and leave the gel coat intact. Great on boat bottoms, graffiti, etc. Google it and look at some of the videos.

 

[kenn]

Soy strippers

I experimented with several approaches to remove ancient bottom paint from our small boat, including sanding, scraping and strippers, and I got the best results with least effort by using a soy-based stripper (eg Boat-Brite, Franmar Soy-Strip). The stuff has low toxicity, a long working time, and is water-soluble. Downside - takes a longer time to work, and is expensive. 90 sq ft might require $150 worth of stripper. But I'd use it again.

Here's another review.

 

[Greg17955]

Thanks for all the advice, I'm planning to try out a some of them over the weekend, starting with the cheapest and working my way upwards if that doesn't work.

Thanks again
Greg

 

[higgs]

I am presently using Srypeze to take off the PO's lousy paintjob on my cabin top. It is not damaging the gell coat and works pretty good.