[DOCRIVERS]

As a much more effective alternative to antifouling bottom paint, Cupronickel coating has been found to last for decades without reapplication, given no collision damage.

In researching this material for my own boat, I found that it has been in use for marine applications, chiefly boat hulls, at least since the 1960s. In Australia in the 1980s, a study was done on sisterships in service as parts of a fishing fleet. 2 boats were compared: 1 a cupronickel hull and the 2nd an identical boat with standard bottom paint. After a year, they were both hauled, and the 1st had zero marine growth, while the 2nd showed the expected accumulation of critters.

The 1st had a fuel bill that was 29% lower than the 2nd. The 1st also achieved a 10% increase of speed through the water at any given RPM compared to the 2nd, apparently due to the low drag from the cupronickel hull . I will be happy to provide that reference for any interested parties, since the study was published. Right after that, the Italian government built a fleet of 8 cupronickel hull fireboats during the mid-1980's. Reportedly, they are still in service with no antifouling problems.

That decrease in fuel burn also meant 29% smaller carbon footprint, not to mention the salutary impact on water quality due to absence of copper and TBT. The latter conclusions are mine. I don't think any of that was in anybody's mind in the 1980's, before we heard of global warming or were as concerned a poplulation as we are now about the environment in general.

The problem then was the cost of the solid cupronickel alloy hull (comprised of 90% copper and 10% nickel) which was considered too expensive for widespread use in commercial ventures. Since then, I have learned (via the internet) that several outfits tried various methods of applying cupronickel over existing hulls of different types. Most of these methods failed due to failure of adhesion of metal to the hull. For example, there have been a coupleof European companies that marketed cupronickel foil to be glued on in squares. ( I think EcoSea was one, but I might dis-remember that). I heard that hasn't worked out too well, though, due to a tendency for marine growth along the junction lines between squares, unless they were meticulously joined, and that proved too expensive & unreliable to be marketable beyond just a few boats. Also, they had problems wih the foil squares coming off.

This month, July, 2009, one of those European companies introduced to the US market a hull coating they call "Coppercoat". They have a website at CoppercoatUSA.com. There's a video that shows their process, but they are using straight copper in some type of proprietary epoxy that they roll on like regular bottom paint. The trouble, as I see it, with that idea is that it's copper, and, even though they claim a low copper leach rate, with the EPA coming down so hard on copper in bottom paints, it would make me nervous that it might not be on the market all that long. As well, their roll-on method has little or no advantage with regard to drag through the water, although they claim it does, it seems to me unlikely to provide much fuel cost savings or speed increase.

By the way, EPA lowered the acceptable leach rate for copper to 1.9 parts per billion of seawater beginning this past January 1st. No current bottom paints meet that standard. That's why all the bottom paint companies are scrambling to come up with something without any copper at all, given that they know EPA is only going to get more stringent with time. I just saw a new entry into that market this week. The name escapes me right now, but I'll come up with it. Anyway, when reading the fine print on the flyer, even that one is still copper-based, albeit without the TriButyl Tin (TBT) that has the EPA really fired up.

That said, most places in the world are still using paints that do contain TBT, a really nasty toxin that poisons marine life, lasts damn near forever, and ends up in the human food chain via predator fish eating the fish eating the small life that ingested the TBT out of the water.

As well, there have been companies in the US that played around with cupronickel back in the 80's, but they never really achieved much market penetration due to cost and the fact that the boating world then just wasn't as environmentally conscientious as now.

Now there's a new company, Marine EcoCoatings, Inc out of southern CA, that is applying cupronickel alloy via a cold spray method. To be sure, it costs more than paint, but it pays for itself over time. In the interest of not waxing commercial here, let me just say that I applied it to my boat hull, and I'm delighted with the result. My understanding is that the website will be fully functional in another week or so, although it's there in rudimentary form now at MarineEcoCoatings.com.

I think cupronickel really answers the need to provide effective antifouling without the necessity of subsequent hassle and expense for haulouts for repainting. That's what made it worth it to me, and I think this represents the future of antifouling. I also think it won't be long before the racing sailors of the world figure out they can go 10% faster than their competitors wearing bottom paint in the same wind.

I'm a newby here, so when I figure out how to do it on this site, I'll post some photos of self & wife on board BLUE CHIPS and during the hull coating application process on the meet & greet place or whichever is the right forum, if someone will inform me about that.

DOCRIVERS