Why Should I Etch My Aluminum Boat Before Priming and Painting?

Getting primer or paint to stick to aluminum is very difficult, and it's a tedious process that typically entails sanding with very coarse sandpaper or blasting down to shiny, bright metal followed by priming with a specialty primer. The zinc chromate primers commonly used in the past are expensive, and less widely available now due to environmental restrictions. It's also not good for painting underwater metals, because zinc is the stuff of sacrificial anodes!

You can certainly still get excellent results with primer and paint, but the secret lies in etching the surface with the right product. Compare TotalBoat Aluminum Etch Wash to Alodine or Alumiprep 33. Our phosphoric acid-based etching wash is easy to use and works fast to create the toothed surface required for epoxy primer or paint to bond effectively and durably.

IMPORTANT: For best results coating aluminum, if using TotalBoat Aluminum Boat Etch Wash during surface prep, dry the surface completely and apply Aluminum Boat Barrier Coat within 1 hour after metal preparation.

Mixing Note: Combine base and activator components in a 3:1 ratio. If you want to mix the entire contents of both cans, just dump the can of curing agent into the can of base. There's enough room in the larger can to hold all the content of both components. Mix thoroughly, then induct for 15 minutes prior to reduction (if needed) and application.

Application Note: If applying antifouling paint over Aluminum Boat Barrier Coat epoxy primer, apply antifoulant while the primer is tacky to the touch. Do the thumbprint test—touch the barrier coat with your thumb. If the primer doesn't stick to your thumb, but you can make a thumbprint, you are within the overcoat window for applying antifouling paint. If you can't leave a thumbprint, you've missed the overcoat window. Sand with 80-grit sandpaper or apply another coat of Aluminum Boat Barrier Coat. Use the thumbprint method again before applying antifouling bottom paint.