How to Properly Paint Your Aluminum Boat

If your boat has seen better days, a new paint job can make it look new again. Maybe you are just tired of looking at bare aluminum. My reason for painting was to seal the seams and rivets with an epoxy sealer that required me to paint over it. Whatever your reasons are for painting your aluminum boat, you should follow these basic steps to make sure the paint will properly adhere to the aluminum. Being the inside of the boat or the outside, it does not matter. These steps will be the same.

The first things that you need to do are properly clean and degrease the metal. If the boat already has paint on it, then you should sand and scrape any loose paint off first. If you choose to use paint stripper to clean off all original paint that is up to you but it is not required. Once you are ready to clean, use an aluminum cleaning product or some kind of detergent. I used a stiff scrub brush with some dawn detergent and water to get anything that may be on the metal off.

The next step is to use an acid etch wash of some sort. This will help prep the aluminum to accept the primer and paint. Without properly preparing the metal, it is very hard for anything to stick to it. This will cause adhesion failure and the paint will not last long at all. A product for this can be purchased at the store or you can make your own at home. A simple and effective wash for this is to mix a 50% mixture of vinegar and 50% mixture of water together. This will further help clean the metal and its slight acidity will help etch and prep the aluminum to accept the primer. Once you have scrubbed and washed with this mixture, rise the boat off one last time.

The next step is also very important. You MUST choose a primer that is meant for bare metal/aluminum. Zinc Chromate is a popular primer that has shown very will to adhere to aluminum. This is being phased out now so it may be hard to find. I used a primer called Zincrom found at some auto parts stores. Rustoleum makes a "self-etching" primer that has shown good results with aluminum. After using this etching primer, I recommend using a bare metal primer that is not self etching. This will ensure a solid base for the paint to adhere to.

Once the primer coats have finished curing, you can lightly sand the surface to put fine scratches in the coat. This will help the next coat properly adhere to the next. Use a good tac cloth to wipe off any dust and particles that have accumulated from sanding.

You are now ready to apply your first coat of paint. You can use a paint of your choice. What you are painting will now decide what type of paint you should choose. If you are only painting the inside of your boat, you can choose a variety of paints and they do not necessarily have to be marine specific. Rustoleum has been used with great results. Rustoleum also makes a marine specific paint now, which is what I went with. This is topcoat paint and is not meant to be below the waterline. For paint that will be below the waterline, an anti-fouling paint is recommended.

To apply your paint, the best technique that I have seen work is the "roll and tip" method. The basics of this method are as follows: Roll the paint on with a good foam roller in small sections. Immediately after this use a good bristle brush or foam brush to go at an opposite angle with the brush at a 45 degree angle. This will create a very smooth professional finish! Let the paint settle, it will self level itself. Do not be tempted to go back and try to touch up. Doing so will show the marks in the paint. Trust the paint to do what it is supposed to do. Two to three coats is recommended for a good solid paint. Allow proper curing times per the manufacturer's recommendations before applying the next coat. Again, you can lightly sand between coats to level out any imperfections before the next coat. Allow the last coat to fully cure before using the boat or putting it back on a trailer. Some paints can take up to two weeks to fully cure!