Repairing An Aluminum Boat Bottom: Expert Tips For Success

Owning a boat can be a lot of fun, but it also comes with maintenance and repair work. If you have a 17-foot aluminum boat that needs bottom repairs, there are several options to consider. The first step is to assess the damage and determine the extent of the repairs needed. Small holes in an aluminum boat can often be fixed with epoxy putty or a product like JB Weld, but larger holes or more extensive damage may require welding or patching with a riveted aluminum patch and sealant. It's important to clean and prepare the surface properly before making repairs, and you may also need to replace rivets or seal seams to ensure a watertight seal. Once the repairs are made, you can paint the boat to protect the repairs and improve its appearance.

Seal the seams and rivets from the outside

Sealing the seams and rivets from the outside is an important step in repairing an aluminum boat. Here are some detailed instructions to help you through the process:

Clean and Inspect the Boat:

Start by giving your boat a thorough cleaning, both inside and out. Use a pressure washer if possible to spray hard at the seams and rivets to check for any leaks. Identify any areas that need special attention, such as loose or missing rivets, cracks, or holes.

Replace or Repair Rivets:

If there are any missing or loose rivets, replace them with new ones of the appropriate size, typically 3/16" for aluminum boats. You may need to drill out the existing holes and use clamps and straighteners to get the new rivets in place.

Prepare the Surface:

Sand the areas around the seams and rivets to create a clean, smooth surface for the sealant to adhere to. Use 80-grit sandpaper and sand until the metal is shiny. Remove any residue from sanding with a solvent like acetone or denatured alcohol. Ensure the surface is completely dry and free of dirt, grease, or other contaminants.

Choose a Suitable Sealant:

Select a sealant designed specifically for aluminum boat repairs, such as an epoxy leak sealer or a product like Flex Seal. These sealants are waterproof and create strong, permanent bonds. Some products may also require a primer to ensure better adhesion.

Apply the Sealant:

Follow the instructions on your chosen sealant for proper application. Typically, you would use a caulking gun to apply the sealant in a bead along the seams and around the rivets. Smooth and manipulate the epoxy with an epoxy spreader to ensure it fills any gaps and creates a proper seal.

Allow for Curing:

After applying the sealant, leave it to cure for the recommended amount of time, which can vary from 7-10 hours to 24-48 hours, depending on the product. Refer to the manufacturer's instructions for specific curing times and conditions.

Final Touches:

Once the sealant has cured, you can sand and paint over the repaired areas for a neat finish. If desired, apply an additional coat of protection, such as a spray-on bed liner or a marine-grade paint designed for aluminum boats.

Remember to wear the appropriate safety gear, including gloves, eye protection, and clothing protection, when handling sealants and solvents. By following these steps, you can effectively seal the seams and rivets of your 17-foot aluminum boat from the outside, ensuring a sturdy and leak-free vessel.

Use epoxy to repair

Epoxy is a strong and waterproof adhesive, making it ideal for repairing an aluminium boat. To repair your 17-foot aluminium boat bottom with epoxy, follow these steps:

Prepare the Surface:

First, ensure that the aluminium surface is clean, dry, and free of any dirt, dust, grease, loose paint, oils, or other contaminants. Sandblast or sand the aluminium with 60-80 grit sandpaper within a 1-inch radius of the repair area until the metal is shiny. Remove any sanding residue before applying the epoxy.

Choose the Right Epoxy:

Select an epoxy specifically designed for aluminium boat repairs, such as the West System G/Flex 650-K Aluminium Boat Repair Kit or the TotalBoat Aluminium Boat Leak Sealer. These products are easy to use and effective in repairing leaking rivets and seams.

Apply the Epoxy:

Follow the instructions on your chosen epoxy product. Typically, you will use a caulking gun to dispense the epoxy onto the repair area. Spread the epoxy with an epoxy spreader, ensuring it covers all the shiny, sanded metal. You may need to apply multiple layers or use a filler to achieve a smooth finish.

Cure and Sand:

Allow the epoxy to cure overnight or for the recommended time specified by the manufacturer. Once cured, you can sand the repaired area to smooth out any roughness and create a fair finish.

Paint or Camouflage (Optional):

If desired, you can apply a mixture of epoxy and pigment to camouflage the repair, as in the case of the G/flex Epoxy repair. Alternatively, you can paint over the repaired area once the epoxy has fully cured, following the manufacturer's instructions for the best results.

Tips and Tricks:

When working with epoxy, always wear gloves, eye protection, and clothing protection to avoid contact with your skin and eyes. Additionally, it is important to store epoxy cartridges at room temperature when not in use and to use them within their shelf life.

Sand the surface

Sanding the surface of your 17-foot aluminum boat is a crucial step in the repair process. Here's a detailed guide on how to do it effectively:

Before you begin sanding, it's important to have the necessary safety gear. Make sure you have safety goggles, a dust mask or respirator, gloves, and clothing that can be washed immediately after the job. The sanding process will release oxide dust into the air, so protecting your eyes, lungs, and skin is essential.

Now, let's get into the sanding process:

• Choose the right sandpaper grit: For sanding aluminum, it's recommended to use 80 or 100 grit sandpaper. This will create tiny scratches and scuffs on the surface, which is actually beneficial as it helps the primer and paint adhere better. You can also start with a coarser grit, like 500, and then work your way up to finer grits like 120 and 180. This will ensure you remove all the coarser scratches and create a smoother surface.
• Prepare the surface: If you're dealing with an old boat, it's likely to have paint or oxidation on the surface. Use the coarse-grit sandpaper to sand away any old paint, surface contaminants, or oxidation until you're left with clean, shiny metal. This step is crucial to ensure the new paint adheres properly.
• Wash the boat: Once the sanding is complete, wash down the boat with a pressure washer. This will help remove any remaining dust, dirt, or residue from the sanding process. After pressure washing, give the boat a good scrub with a coarse-bristle brush and soapy water to ensure all contaminants are removed. Finally, rinse the boat thoroughly to get rid of any soap residue.
• Dry the boat: After washing, allow the boat to dry completely before moving on to the next step. It's important to work on a dry surface to ensure the best results.
• Protect surrounding areas: Before you start sanding, make sure to protect any areas of the boat that you don't want to sand. Use tape or covering to mask off these areas and ensure you only sand the intended surfaces.
• Start sanding: You can choose to sand by hand or use power tools like an electric sander or angle grinder. If you're sanding by hand, use a circular motion and apply even pressure across the surface. If you're using power tools, follow the manufacturer's instructions and always put your safety first. Wear gloves and eye protection when operating power tools.
• Sand in sections: To ensure a consistent finish, it's best to sand the boat in sections. Work on one section at a time, making sure to overlap slightly with each pass to avoid missing any spots. Pay extra attention to areas with angles, like chines and transoms, as they can be tougher to sand.
• Remove sanding residue: Once you've finished sanding, make sure to remove any sanding residue from the surface. Use a tack cloth or a clean, dry cloth to wipe down the entire boat, ensuring no dust or residue is left behind.
• Inspect your work: After sanding, inspect the surface closely to ensure you've achieved the desired smoothness and shine. Look out for any scratches, scuffs, or uneven areas. If you find any imperfections, you may need to repeat the sanding process in those areas, using finer grit sandpaper.
• Prepare for the next steps: After you're satisfied with the sanding job, the boat is now ready for the next steps in the repair process, such as applying primer and paint. Make sure to follow the manufacturer's instructions for the specific products you're using.

Remember, sanding is a crucial step in repairing your aluminum boat. It ensures the surface is properly prepared for the application of primer and paint, which will help protect your boat and give it a new lease of life. Always take your time, work in a well-ventilated area, and put your safety first.

Clean the boat

To clean a 17-foot aluminum boat, you will need a few essential supplies and a good amount of time and effort. Here is a detailed guide to help you through the process:

Prepare the Boat for Cleaning:

Before you begin, park the boat on its trailer in a shady spot with ample room to work. Avoid cleaning in direct sunlight as the aluminum can get too hot to touch. Ensure you have all the necessary supplies, including a garden hose, a bucket, biodegradable car soap or boat soap, a scrubber or sponge, a pressure washer (optional), an aluminum boat cleaner, a buffing cloth or machine, and protective gear such as goggles and gloves.

Initial Wash:

Start by spraying down the boat with a garden hose to loosen any dirt and grime. Fill your bucket with hot water and add car soap or boat soap. Use a sponge or scrubber to scrub the boat's surfaces, including the hull. For stubborn areas, you can use steel wool to scour them. Rinse off the soap and dirt thoroughly.

Apply Aluminum Boat Cleaner:

Dilute the aluminum boat cleaner with water as per the instructions on the product. Soak your scrubbing brush in the solution and thoroughly scrub all aluminum surfaces, paying extra attention to any areas that were not cleaned during the initial wash. Check the product instructions to determine if the solution needs time to set into the metal or if you can rinse it off immediately.

Buffing to a Shine:

Once you have rinsed off the cleaning solution, it's time to buff the aluminum to restore its shine. For a small boat or light oxidation, you can opt for hand buffing, but a buffing machine will make the job much quicker and easier. Apply aluminum polish to a buffing cloth or pad and work it into the boat's surface using circular motions. If using a buffing machine, start by applying the polish to the pad while it is in motion, then press the pad into the aluminum and move slowly from side to side. Remember to keep adding polish to the pad as you work.

Final Rinse and Inspection:

After buffing, give the boat a final rinse to remove any remaining residue. Inspect the boat to ensure that all areas are clean and shiny. If you notice any spots that were missed or areas that require additional attention, go back and repeat the cleaning and buffing process as needed.

Maintain Shine with Boat Wax:

To maintain the shine and protect your boat, consider applying boat wax at least once a year. This will help preserve the aluminum's appearance and make future cleanings easier.

Use a caulking gun

Once you have shaped and cleaned the metal, you can use a caulking gun to repair the hole in your aluminium boat. Firstly, you will need to prepare the surface of the boat by sanding the aluminium with 80-grit sandpaper within a 1" radius of the leak until the metal is shiny. Remove any sanding residue before application.

Next, attach the mixing tip to the cartridge and insert the cartridge into the caulking gun. Pull the trigger to apply the epoxy adhesive to the hole. You can use an epoxy spreader to manipulate the adhesive and spread it to a thickness of 1/8" to 1/16" over the hole.

The caulking gun can be used to apply the adhesive in less than ideal conditions, even in temperatures as low as 40°F. For the easiest application, use a caulking gun with a minimum ratio of 8:1.

Frequently asked questions