Does anyone have information or views on antifoulings compatible with aluminium? Since tri butyl tin (TBT) was banned internationally we have used a US non-metallic product manufactured in Falmouth, Mass, by E Paints, with great success. This product SN-1, is used by the US Coast Guard on their aluminium craft and we have found it to have excellent antifouling properties in the Caribbean and the east coast of the USA and Canada (warm and cold waters).

One problem is that this product is not available outside the USA and, contemplating a move to European waters in 2013 we are already wondering what effective products are available in Europe?

John, I 've no idea whether it works but my project for this winter was to make an ultrasonic anti fouling system. There are quite a few expensive commercial systems out there that promise much but with flimsy evidence. I bought a kit from Australia and have happily been soldering away. The cost of course was a tiny fraction of an 'off the shelf ' product. My guess is that it probably will have minimal effect but it 's been fun building it and I discovered loads about electronics on the way. I 'll keep you posted as to how it works (or not) but we will be using it on GRP and not aluminum. Needless to say despite the DIY ultrasound we spent last weekend painting the bottom with Interspeed Ultra!
Simon

Simon. How very interesting. I would be very interested to know how well it works in practice. Some years ago I had a slight involvement with, also an Australian system, for cleaning heat exchanger tubes using a combination of ultasonics and high pressure water jetting. The ultasonics certianly made the jetting process much more efficient.

I like your belt and braces approach but how will you evaluate the effect of the ultasonics?

John,
No not scientific at all I 'm afraid. The trouble is I don 't have that much faith in my soldering iron to risk an early season haul out and paint when the ultrasound proves useless! And that 's been the problem with all the written up trials I have seen. None have been properly scientifically evaluated despite companies charging megabucks for some pretty simple electronics. In reality what I am hoping for is that it will keep the prop free of growth as it is mounted adjacent to it and, hopefully, increase the amount of time between haul outs. I 'll have a subjective idea after a year as to whether it 's made any difference at all. Keeping my fingers crossed!
Simon

Just completed my Ultrasonic anti fouling project whereupon, having figured out I had blown fuse, I pressed the button and, amazingly, it started making whale like utterances that must surely deter any sensitive minded barnacle. Never have been so excited by a red LED and a very high pitched series of squeaks. If nothing else it should keep dogs away! Maybe that 's why whales don 't get covered in barnacles? We fit it in the boat next weekend and then we will hoping for the best.