Fixing leaking seams & rivets
As aluminium boats age the accumulated wear and tear on its riveted joints can take a toll on the rivets themselves. Rivets can stretch and eventually loosen, leaving gaps and leaks. Severely damaged seams may require new rivets in combination with G/flex Epoxy. Most leaks can be easily repaired with this kit and the following:
• Wire brush
• Propane torch or heat gun
1. Determine the exact locations of leaks by putting the boat in the water or by filling the boat part way with water to see where it leaks.
2. Mark the leak locations with an indelible pen.
3. Allow the boat to dry.
4. Roll the hull over if possible for easy access to leaking sections.
5. Abrade along the seams and rivets with a wire brush to remove any debris and expose bright metal. A wire brush attachment on drill will make the job easier.
6. Dispense equal volumes of G/flex 650 resin and hardener into a mixing cup and stir thoroughly with the mixing stick (1). Transfer the mixed G/flex epoxy to the plastic syringe. (It is quicker to fill the syringe by removing the plunger and pouring the epoxy into top, especially in cooler temperatures. You should also find it easier to extrude the epoxy in cooler temperatures if you trim the syringe tip back to about a 189 cm opening.
7. Use a propane torch or heat gun to boil off any remaining water under the rivets and in the seams in 31cm to 46cm long sections or areas (2).
8. Apply a continuous bead of G/flex, using the syringe, along the heated seam and around the rivet heads. The epoxy should thin out and flow into the smallest crevices (3).
9. Heat the metal with a torch or heat gun as necessary to thin the epoxy to a water-like consistency and to move it along and penetrate deeply into seams and under rivets. Continued moderate heating will cause the epoxy to gel and cure quickly. Do not heat the epoxy to the point where it discolours or begins to smoke.
Filling larger gaps in seams and rivets
If new rivets are not available to draw together large gaps, it is possible to successfully repair larger gaps in seams and loose rivets by completing the previous 8 steps and following with these additional steps:
1. Mix a batch of G/flex 650 Epoxy as described earlier. Stir in 403 Microfibre Blend Powder to thicken the mixture to a "mayonnaise" consistency.
2. Force the thickened epoxy mixture into the seam gaps or under the leaky rivets with a putty knife or mixing stick while the initial coat of G/flex 650 is still uncured (4). You may also use the syringe filled with the thickened mixture to force epoxy into the gaps. Trim the tip back as necessary for the thicker material.
3. Keep forcing the mixture through the seam until you see epoxy on the other side of the hull. Thickened epoxy bridges gaps and stays in the seams while it cures.
4. Wipe uncured excess epoxy from both sides while uncured with paper towel. Use solvent (lacquer thinner or acetone) sparingly if needed to remove stubborn epoxy. Avoid washing epoxy out of the seams or dissolving paint.
5. Allow the epoxy to cure overnight at 65°F (18°C) or warmer before using the boat. You can speed curing by applying moderate heat.
6. Apply a spray paint to match the aluminium or the existing paint if desired.