Aluminum can be difficult to coat because smooth surfaces provide little for polyurethane to bond to. If you plan on applying Durabak products to aluminum, follow these helpful hints for best results!
If you are coating a low grade aluminum (no shine) a simple pressure washing may allow you to coat the aluminum. If you are coating a high grade aluminum, (high shine) you may need to mechanically roughen the surface and use a primer that matches the grade of the aluminum to be coated.
Unless the surface of the material to be coated is highly sealed (like teak wood, stainless steel, or a high grade of aluminum) or unless water cannot be used to prep a surface for some safety reason, a Clorox rinse, keeping the surface to be coated wet for at least 20 minutes, followed by a horizontal/ vertical pressure wash at 2500 psi using a 15 degree nozzle will remove and clean at least 95% of all dirt, grease, oil, and grime from the surface of the substrate to be coated. When the surface is clean and dry, then perform the 2 inch patch test.
One layer of Durabak or Durabak 18 applied at 15 wet mills will do a good job for a boat used 5 or 6 times per year. Two layers applied at the same thickness will protect that same boat deck for 7 to 12 years. You can use the Durabak indoor for the first layer and the Durabak 18 for the second layer. It is NOT recommended that you mix the two products (Durabak and Durabak 18) while they are in liquid form because if they are mixed, the total mixture will not dry. If the Durabak is used first, allow at least 12 hours before applying the layer of Durabak 18 to the dry and cured out Durabak layer. If you prefer to just use Durabak 18, on a 70 degree day in roughly 30% humidity, you can apply the second coat in approximately 45 to 60 minutes. Never apply either Durabak material at less than 8 wet mills thickness as the material may not dry. This is the hardest urethane on the market, but it is a chemically cross-linked material so it must have at least 8 wet mills to start the chemical reaction to set up drying and curing.
One of the reasons that Durabak is the most versatile and reliable coating around is that even if a mistake is made during the application process, Durabak is EASY to repair!
- Durabak naturally bonds to itself, so for damaged surfaces, a quick cleaning and re-coating is often all that is needed!
- If the underlying substrate was prepared improperly, peel off any Durabak which hasn't bonded and is easily removable.
From there, follow standard Durabak application instructions.
Below are some pictures of a boat deck repair!
Below is a photo of the Portland Spirit, which has Durabak 18 Non-Slip on its walking decks!
Many other clients have used Durabak products on their private 25-125 foot boats!
We have even applied Durabak 18 to Coast Guard Cutters and Golf of Alaska oil tankers!