How To Prep An Aluminum Boat For Paint

Owning a boat opens up a world of opportunities. You visit places that not many else have, entertain a small fishing trip, or even take family and friends for a spin. Owning a vessel, be it big or small, is undoubtedly a treat and makes for something you could call your pride and joy. But as with any vehicle, a boat requires some level of maintenance. 

One significant aspect to look out for is your boat becoming rusty, the result of dirt that has accumulated over time. Having rust spots on a boat and taking the same watercraft out isn't the best idea. Before you know it, your little fishing trip may end up with you swimming with the fish you were supposed to catch. If you are looking to avoid these experiences, then attending to the rust and painting your boat could surely give you a pleasant experience as well as a nice fresh-looking boat to take out. 

Here's our guide on how to prep and the things you might need to know before attempting to paint your boat.

Prepping Your Boat for Paint: An Overview

Owning an aluminum boat indeed brings many advantages when prepping for paint over a fiberglass boat. First, less work means less cost and a smaller margin of error. Just imagine scraping that thick gel coat used on non-aluminum boats to start preparing for paint. That will surely cost you a pretty penny. If you are doing it yourself, it means much more elbow grease and work. 

Another advantage of having an aluminum boat is that it is less likely to have significant damage to its body due to aluminum denting upon impact during an accident rather than cracking or breaking.

Taking the Dirt Away

Finding a large dry area would be highly beneficial for this particular endeavor. The size of the space needed depends on the size of your boat, and the location you choose should also be a place you don’t mind getting wet. 

The next part entails hoisting your boat up so you can inspect the underside, which is often where all the dirt and debris that hits the boat would have taken its toll.

Things you need to prep and wash your aluminum boat:

  • Dry and spacious environment to paint
  • Power sander
  • Varying strengths of sandpaper
  • Cleaning agent of choice

You can start by getting rid of everything in the boat, including the old carpets and any items that could restrict the sanding process. You can refer to our article on How to Clean Your Boat Carpet to take your boat restoration to the next level. 

Once you have removed everything from the boat, begin by sanding off any loose paint and rust. The amount and size of the rust debris will determine the strength and grit of the sandpaper you need to use. Additional equipment, such as a power sander, may be necessary in cases of severe rust. Once you eliminate the loose paint and rust, it is now time to eliminate any external agents on the boat, such as old wax. To do this, you could use a dewaxing solvent.

One key to an excellent finish is meticulous prep work. The boat needs to be washed thoroughly, which calls for some serious elbow grease. Again, the condition of your boat plays a significant role in the items required. If your boat has small traces of dirt, which seems easy to remove, a simple mixture of mild soap and water would be sufficient to take the dirt off. However, if those stains are stubborn, a simple DIY solution would be to mix 50% distilled vinegar and 50% warm water. If you prefer a pre-made solution, some products are specifically made for this purpose.

Spray either the water and mild soap mixture or the distilled vinegar and warm water mixture using a spray bottle all over the boat, leave it for 60 seconds, and then wipe it away. Your boat should now be clean and smooth. A quick rinse-off would do the trick of getting it ready to be painted. An important point to note would be to use only fresh water and not seawater or saltwater.

Getting That Shine On

Your boat is now clean and dry, and it is time to polish. Polishing your craft before painting increases your margin for error and enhances the look of the finished product. You can start by picking the best-suited boat polish. Make sure that your selections are limited to aluminum-grade boat polishes.

Items needed to polish your boat:

  • Aluminum grade polish
  • Power buffer
  • Dry and clean cloths

Applying the polish could either be done by applying it by hand or using a power buffer. One tip is to carry out this process using your hands to ensure all those tough-to-reach spots are covered. Work in small circles and inspect the boat thoroughly, making sure to apply the polish compound on every inch of the boat.

After applying the polish on the entire surface, take a step back and walk around the boat. Upon closer inspection, verify whether you have managed to reach every nook and cranny. Are you confident that you covered your entire boat? If your answer is affirmative, then it is time to allow the polish to dry completely. The time taken to dry can vary depending on the brand or particular polish used. Refer to the instructions to get an idea of how long you would have to wait. Drying time would usually last 5 to 20 minutes. Upon drying, take a dry clean cloth and wipe the entire boat down.

Final Prep Before Paint

You are now one step closer to having the nicest-looking boat in the neighborhood, and it is now time for the final process: Getting ready to paint. 

Before applying the paint, it would be advisable to create a checklist of all the equipment you may need. Creating a checklist would ensure that you wouldn't have to stop midway and run to the store, ensuring a smooth process.

Final items needed before painting:

  • Oil-based primer and paint thinner
  • Paper or plastic to cover the floors or any item which the paint could get on
  • Paint sprayer or brushes
  • Water-resistant paint

Once these items are at your disposal, you can start on the final step in getting your boat looking new. Insisting on the highest quality products can make all the difference and ensure your paint lasts longer and shines brighter.


When it comes to painting an aluminum boat, it is an involved process. By doing it yourself, you stand a chance of saving a nice chunk of change. Plus, there is nothing like the satisfaction of admiring your own handiwork. However, if you don't feel up to the task or aren't confident in any of the steps listed above, it may be best to consult a professional for further assistance.