Three methods of paint removal available to you to successfully remove the paint from a boat: mechanical sanding, heat guns, and (the best method) paint stripping chemicals.
Mechanical sanding is the most labor-intensive method. It’s messy and takes countless hours of hard work. The process consists of removing the paint or varnish from the boat finish by manually sanding it away inch by inch foot by foot. You’ll need plenty of sand paper and quality power sanders. However, based on the size of your boat and the intricate details you may also consider having multiple sanders including an orbit sander and a detailed finishing sander. The process will take time and you will have to change the sandpaper constantly. Start with course sandpaper but be extra careful of stripping too much paint too much material that will create a depression in the underlying substrate. This danger can be minimized by constantly keeping the power sander moving. Never push down too hard on the sander or hold it on one location for too long.
Some “marine experts” strip paint mechanically by using “mechanical scrapers” with sharp blades. We do not recommend this procedure for novice carpenters. It can cause a disaster including gouging the wood or fiberglass substrate, or even causing serious injury. However, experts can do this process safely and effectively.
Another method of removing marine paint is by using heat guns. Using heat to strip paint on a boat, of course, requires care. The process can be dangerous and should never be rushed. Safety first is the rule when using heat guns. You must make sure there is no fuel or other flammable substances in the area that is going to get stripped. Start in one small area at a time and apply the heat in a controlled methodical manner. The biggest danger is holding the heat in one spot too long and scorching the underlying surface. Constantly move the heat gun and stop immediately if there is a smell of something burning. After the paint has been softened by the heat use a putty knife or scraper or to remove the residual paint. We do not recommend heat gun paint removal on your boat unless you have mastered the skills on other surfaces. Boats are filled with gasoline and there is always a major risk using heat guns. Please exercise caution!
The best method of paint removal for boats is the use of chemical paint strippers. However, on a boat they can work too well and damage the surface beneath the paint, especially if it is fiberglass, so great care must be taken. Chemical paint strippers can be messy and affect other areas on your boat but if you follow the precautions, you’ll find chemical paint strippers as your best alternative for the removal of marine paint:
1. Mask off all areas that you don’t want stripped.
2. Use heavy-duty plastic drop cloths and “blue” masking tape.
3. Select a chemical pain remover specifically labeled for marine paint removal. Our favorite is Peel Away Marine Safety Strip from Dumond Chemicals.
4. Use a paste so that it will adhere to all vertical surfaces
5. Work slowly. Do “test patches” and determine the “cure time” of the paint stripper you have selected. Different marine products will have significantly different sure times based on the surface and weather conditions.
6. Marine chemical strippers might need to be applied more than once on tough marine paints.
7. Give the stripper time to work. It could take as long as 24 hours.
8. Carefully scrape or wash the dissolved paint.
9. Follow the procedures on the label for the optimum results.
When you complete the paint removal process it is important to prepare the boat’s surfaces for proper refinishing. Clean the surfaces carefully and wipe dry. Then make sure the surfaces are “baby smooth” by carefully sanding using progressively finer grits of 80, 100, then 220 grit sandpaper.
Stripping marine paint is a big job but necessary to keep your boat in the best condition!