anti-fouling

[Maurice55]

Hello every body,
Nearing launching time of my long term project, I'm getting more and more interrested in anti-fouling paints. Having hoped to find something environmently friendly, the only thing I got was a mixture of camel fat and lime? so for some odd reason I looked elsewhere.
Now,I've heard of Copper-Boat, which sounds a lot better than the concentrated violent poison normaly used.
Has anybody got any feed-back on this product, specialy on metal boat.
If there is any suggestion of the camel fat league, I would quite like to hear as well.
Cheers..... Yours......M.

 

[Gaffer]

These long term copper/epoxy antifoulings are OK in theory but in practice they tend to fail for a number of reasons, although having said that I have spoken to many satisfied users of this system.

Getting it to adhere to the substrate is one of the most popular failings, although this is an application problem and nothing to do with the coating. If you prime your steel boat with something along the lines of an epoxy coal tar or pitch epoxy and follow at the right time with an epoxy/copper system then you have the best chance of success.

Don't forget that you have to abrade the surface each year to keep it active, many people think you can just leave it and it will work for ever.

A lot of reasearch is going on at the moment to formulate an antifouling which has little or no "poison" in it, and the latest thing is a pure "teflon" coating similar to your non stick frying pan, and these have been found to be good on frequently moving vessels such as ferries etc, but the fouling starts to build up if the boat has remained stationary for more than a week or so............

 

[Fr J Hackett]

A recent review ( Sailing Today ) of a copper foil backed with epoxy as an adhesive looked promising I remember speaking to its " inventor " a year or so ago befor its launch onto the market he had used it on a rudder for several years prior to the extensive tests refered to in the review and said there were no problems. The drawback is its expensive but when looked at over the life expectancy its not so bad still you would have to shell out about £3000 initially. Also preperation and application are likely to be critical to the performance and results. I intend to do my rudder and wind vane rudder blade next spring to see if it really is worth it. Environmentally it is far less polluting than current systems.

RAG @ STICK

 

[oldharry]

Go round the yard(s) in your area and see which boats are the cleanest, then find out what AF they used.

There is an enormous variation in the effectiveness of different compounds geopraphically. For example Blakes Titan workls superbly in Chichester harbour, while International Bootopping seems to actually ATTRACT weed here. However Internationals' products appear to work better than Blakes on the West Coast....

 

[vyv_cox]

I coated my keel with Coppercoat about four years ago. I ran into environmental problems in Holland, which prevented me from doing the hull, but I'm now quite glad.

I found applying the stuff to be very hard work. It is viscous and the copper settles out quickly. A decent finish is very difficult to achieve. Adhesion to the epoxy substrate and primer was not a problem but now that corrosion is occurring beneath the epoxy, some of it is coming off. Air temperature during the job is quite critical and it can only be done in the (UK) summer or in temperature controlled rooms. It was expensive and you need to ensure keeping it for more than about 6 years to make economic sense, not counting labour costs, of course.

The cost of the sheet material referred to elsewhere seems astronomical, will it really last as long as is needed to justify it?

 

[Maurice55]

Just about what I expected so far, but nobody mentions steel hulls when some people around my yard say: copper on steel? no way.
Any comments?
And what is the environment issue in Holland?
Thanks any way.....M.

 

[Gaffer]

If you refer back to my first reply, I did in fact mention application to steel.

I also mentiond epoxy coal tar or pitch epoxy, and some people apply this coating to GRP, and even wood, this should be followed by at least one coat of antifouling primer at the correct interval, then your coats of antifouling, copper based or not.

The antifouling goes on the antifloulng primer..........

The antifouling primer goes on several coats of pitch epoxy or epoxy coal tar.....which can be on steel, GRP or wood, even concrete.

By this time the top coat ( the antifouling ) is so far removed from the original substrate whatever it may be, that the one has little or no influence on the other.

The only circumstance in which copper based antifouling should not be used on steel is if it is galvanised or hot aluminum sprayed.

Just think, there is hundreds of thousands of tons of commercial shipping out there, all steel, and every one of them has cuprous oxide or cuprous thyocyanate based antifouling on, now they would not be using copper if it was a no no on steel.

 

[vyv_cox]

What you describe is virtually exactly what is on my keel, which is iron. Corrosion under the coal tar is now lifting everything off in a few places and this is difficult to repair. So although the Coppercoat may be effective for ten years, that assumes that the substrate will be as well. Which on steel is not guaranteed.

The environmental situation in Holland is that no copper-based antifouling is allowed. None. When I did my keel the situation was slightly more relaxed and I got away with it, but now it is being enforced, in some places more vigorously than others, I probably would not. The legal situation as has been explained to me is that you can have copper-based antifoulings on your boat, you can buy it or you can sell it. You cannot apply it. A very Dutch solution. In my yard/marina the rule seems to be almost completely ignored but I believe this is not the case elsewhere. Standard answer is to go to Belgium and apply it there.

 

[dk]

Maurice

The only two remaining products in the UK are Copperbot 2000 (formulated by Wessex Resins - makers of the WEST epoxy system), and Coppercoat (The original Copperbot now made by Aquarius Marine Coatings in Poole).

Both are excellent products IF they are applied in the right environment to a properly prepared surface. Both are water-based epoxy products which require a minimum of around 15 deg C to cure properly. And, being epoxies they will simply 'trap' any moisture already in the hull. Best applied in a controlled environment (heated and humidity-controlled) after drying out the hull for as many months as you can. Follow the makers instructions to the letter and you'll end up with a simple pressure clean job every season for the next 10 years or more.

No, I don't work for either, but have had a great deal of experience in the product and have been monitoring boats that use it for the last 10 years!

Both Wessex and Aquarius are very willing to discuss the technicalities with you and will send you brochures on the whoile procedure.

Good luck, D