Slicker Means Quicker
A slippery new breed of bottom paint promises performance—but at a price.
These days it seems like nearly everyone is talking about going green. Some people are going all out, living in solar-powered homes and driving hybrid cars, while others require a bit more convincing before they hop aboard the tree-hugger express. But whichever side of the great environmental debate you come down on, one thing is pretty much universally unchallenged: If a new product comes along that is less harmful to the environment than the status quo and works just as well if not better, it’s worth a look.
Such is the case with the new, “nonstick” hull paints like the Intersleek 900 system from Interlux, Hempel’s Hempasil, Sherwin-Williams’ Sher-Release, and SigmaGlide from Sigma Coatings. These paints are so slick that barnacles and weeds can’t get a good hold, which the manufacturers claim eliminates the need for the environmentally harmful biocides, like copper. You no longer have to kill the growth on your hull because it simply can’t live there in the first place. Furthermore, these paints’ slippery nature is said to reduce hydrodynamic drag, providing increased speed and/or reduced fuel consumption, thus providing a one-two punch of environmental soundness. And though they aren’t cheap to buy or apply, they may actually save some owners cash in the long run.
I first heard about nonstick paints—and in particular the Intersleek 900 system—from Billy Smith, vice president of Trinity Yachts. Smith, a 35-year veteran of the marine industry, is one of this paint type’s most vocal supporters. Trinity is currently building a 167-footer powered by MTU 20V 4000s, and with powerplants like those, it’s clear the owner has speed and performance high on his list of priorities. Looking for ways to make the boat as fast as possible, Trinity began thinking about applying Intersleek 900 to the bottom. But first it needed a test boat. Smith volunteered his 34-foot Mainship Redeemed, and the results left him impressed. “I had had a diver go down and check out her hull a few times, and he said it was clean. So after a year and a half I took her out to a barrier island and dove in [to see for myself]. I was amazed. What little growth there was on the boat I could wipe away with my hand. The barnacles and weeds slid right off.”
What’s more, Smith claims he has noticed slight gains in both his boat’s speed and efficiency. And he says, where traditional hull paints he’s used had to be reapplied every year or so, he doesn’t anticipate having to replace the Intersleek 900 until five years from its original application, which saves him time and money.
Impressed by his tale, I decided to go to the experts to find out how this paint works. Elenor Ekman, marketing manager for Interlux, corroborated some of Smith’s observations. She explained why he was able to slide normally steadfast barnacles around his hull with a nudge from his fingertips. When submerged, she says, the paint is super-slick because it’s produced using fluoropolymer chemistry, which yields a durable yet rubbery surface that’s resistant to the glycoprotein that fouling organisms secrete, hence making it difficult for them to adhere strongly to the surface.
“The idea for a paint like this has been around for 15 years or so,” she explained. “Intersleek 400 and 700 were the 900’s predecessors, but they lacked the fluoropolymer, and [therefore] the surface qualities which make the Intersleek 900 so much more smooth and durable. [The paint also] significantly reduces the AHR [Average Hull Roughness], which is so important for optimized speed.” Ekman maintains that that additional sleekness can account for a six-percent or better increase in fuel efficiency and notes that the lack of biocides in the paint does indeed earn the paint kudos from environmentalists.
Cleaning an Intersleek 900-coated hull is easy too. In fact, if a boat is run at somewhere around 13 mph or faster, the paint essentially becomes self-cleaning, with growth being pushed off by the water rushing past it. Most planing-hull boats that are run regularly (a charter fishing boat for instance) need only a bare minimum of hand-cleaning to keep the hull virtually spotless.
However, Intersleek 900 and paints like it are not without their downsides. Most notably they’re expensive. Intersleek 900 sells for about $800 per gallon, and that’s not including the cost of the professional application the paint requires. Also, nonstick paints work best on boats that are run at 13 mph or faster at least once every two weeks. Otherwise, growth can latch on as the hull sits idly in the water and become too thick to wash away just by taking the boat out for a spin. If owners of infrequently used boats choose nonstick hull paint, they should be prepared to perform or pay for regular cleaning, especially in warm waters.
However, if your boat regularly achieves enough speed to drive away excess flora and fauna, the price of the paint and application could be worthwhile. Intersleek 900 is already popular with industrial and military ships that run all the time and quickly make up for the pricy paint job with that increased fuel efficiency. And though the paints are fairly new to the world of pleasure boating, Ekman believes they will eventually become popular, particularly in the charter-fishing market, where they seem like a logical choice.
Figuring out if nonstick hull paint is a good choice for you depends on the variables in your personal boating equation. But if you’re into green technology that can make your boat faster and more efficient (and these days, who isn’t?) this is definitely a paint that you shouldn’t let slip your mind.
This article originally appeared in the October 2011 issue of Power & Motoryacht magazine.