New barrier coating combines epoxy and copper
for advanced hull protection
By Leslee Jaquette
Boat hulls are the most important, yet most overlooked, part of a boat. When they are clean and smooth, they add to the boat’s performance and the owner’s enjoyment; but when the hull of a vessel is covered with barnacles, it coats the owner money, time and energy.
In the Northwest, owners traditionally pull their boats out of the water, scrub the hull and apply a standard sloughing bottom paint with cuprous oxide. Over time, however, environmentalists believe the sloughing action of the paints deposits toxins in the water and damages the environment. As a result, anitfouling paint use is becoming increasingly restricted by the Environmental Protection Agency.
In response to this problem, American Marine Coatings (AMC) of Seattle has developed a product called CopperPoxy — which marries epoxy and copper into a barrier coating. Best applied by boat builders to new boats in the mold, the antifouling barrier system provides a hard, durable coating that reduces bottom care costs over time. This impermeable barrier not only prevents hard marine growth, it meets EPA standards for protecting the environment.
“I believe it is a good value to the customer,” said Jim Lindell, owner of Jim Lindell Co. Inc. of Camano Island, Washington. He has applied CopperPoxy in the mold to all new Lindell 36 (formerly known as Ocean Flite2) yachts over the past two years. “It’s a value to us because it’s actually cheaper than applying conventional bottom paint. It’s a value to the customer, because it gives him 10 years he doesn’t have to paint the bottom.”
Lindell uses four gallons of CopperPoxy on each hull of his sport- fishing boats. So far, feedback from owners has been positive.
“Everyone thinks it’s great because all they have to do is scrub it off from time-to-time with a sponge,” Lindell said. “They like the easy cleanup, how it stops hard growth and how it eliminates painting for at least a decade. They also appreciate that the coating is a better product for the environment.”
How Does It Work?
Mariners have known about the effects of copper on boat hulls for centuries. A copper sheathing was used on sailing ships to keep wood-eating worms out and to resist growth. Ken Draper, president of AMC, explained that copper flakes in epoxy work very much the same way.
Essentially, the copper in the coating tastes bad to marine life. Although animals such as barnacles and zebra mussels don’t like the stuff, they aren’t poisoned by the coating. While soft growth will gradually accumulate on a hull according to boat use and water conditions, the hard coating makes it easy to scrub off with a sponge or pressure wash.
During scrubbing, no chalky debris or toxins slough off in the water. In addition, the mixture is so hard (harder than gelcoat) that it acts as a virtually 100 percent water-resistant barrier.
Ed Euler, vice president of production at AMC, described CopperPoxy as a structural coating. “It is 10 times harder than the hardest conventional paint,” Euler said. “It’s a barrier coating and antifoulant in one.”
CopperPoxy is a combination of copper flakes within epoxy resin. Each gallon of the coating weighs 16 pounds total, and half of that weight is pure copper metal flakes. According to Euler, who has helped pioneer the coating application in the mold, the product dissolves at about the same rate as the copper metal water pipes in a house. “Because the flakes are dispersed evenly throughout the epoxy, examples of the coating lasting 10 years or longer are common,” said Euler.
Founded in 1992, but not actively publicized until receiving EPA approval three years later, AMC markets CopperPoxy to boat builders and dealers. Due to the newness of the product, boaters need to be educated about its benefits before they can appreciate the value, said Draper, from AMC’s headquarters on a barge floating on Lake Union.
He added that while the product “selling itself,” a couple of traditions tend to stand in its way. For example, boaters are simply used to applying bottom paint every spring when they prepare for the season. Also, many boats these days sport black bottoms, fenders and lines.
“We simply can’t change the copper color,” Draper said. “But color can be applied down to the chine.”
Currently, AMC ships the coating (which costs $295 per gallon or $85 per quart) directly to builders, yards or individuals. Draper noted that it doesn’t sell well off the shelf at a retail store, because staff members need to be able to explain the product.
Draper said people tend to have the perception that the coating is more expensive than conventional bottom paint. The key to the product’s cost savings relates to the fact that one coating costs less in labor.
It takes a lot longer to apply eight coats of paint than it does to spray in the mold one, 4 ml thick layer of CopperPoxy. While Lindell has not done hard research, he said, “We haven’t done a cost analysis — it’s just the right thing to do for our customers,” said Lindell.
Lindell and four other builders incorporate the coating in the manufacturing process. Nordic Tug in Burlington, Washington, has applied CopperPoxy in the mold to a half-dozen vessels. Five years ago, the Hoquiam, Washington, builders of the 100 foot Shadowfax sailing yacht applied it post-mold to the yacht’s hull. They used 21 gallons on the boat.
Builders in Taiwan and Europe are learning about the product and placing orders. Boat designer and sailor John Conser uses it these days on each of his Conser 47’s and 52 foot Wally yachts. He said the coating is not only practical but pretty. “It gives a yacht a million-dollar look when the bottom gleams like a shiny copper penny.”
Several other international companies advertise various forms of copper-epoxy coatings. CopperPoxy’s closest competitor, Epcotek 2000, is an epoxy resin with copper flakes. It differs from AMC’s products in that it requires multiple coats and is designed to be used post-mold only. Another product, called Copper Bot, is made in England, and requires the customer to mix the metal flakes in the can.
Within the next year, AMC’s goal is to gain registration in California and Canada. During the same time period, Draper expects 10 more builders o use the “in the mold” system at factories. While six boat yards currently apply CopperPoxy post-mold, he foresees that number increasing to 16 within a year.
While the product is best applied in the mold to new construction, he predicts individual boaters will increasingly seek this ecologically friendly product. “We’re going for a niche market,” Draper said, “CopperPoxy is for people who want an environmentally helpful, long-lasting coating.”
Who can use CopperPoxy?
The best application is in the mold. You can also apply it post-mold on a new boat; on a boat that needs bottom work or you can remove all the old paint on an old boat. It works on all sorts of boat hulls: fiberglass, steel, concrete and wood composite hull materials.
• How can It last 10 years? CopperPoxy uses 100 percent solids epoxy resin. The resin is extremely hard, and unlike other antifoulants, it does not degrade even when scrubbed hard.
• Is it hard to apply? No, not difficult, just different, You are not painting the bottom of your boat; you are applying a coating of copper metal. It is very important to follow the guidelines.
• How does it protect the environment? CopperPoxy does not deposit toxins on the floor of waterways. The hard surface does not slough off when scrubbed.
• How do you prepare the boat bottom? You must remove all existing antifoulant paints
• What equipment do you need to apply the product? You can use a brush, conventional spray (HVLP) or airless spray.
Reprinted from Sailing Magazine, March 1998