homer
Well-Known Member
Planning a long live-aboard voyage, we thought it would be a good idea to Coppercoat the hull and, thereby, avoid anti-fouling costs for some years. In April 2008, we had the hull sandblasted and, whilst the hull was completely dry, decided that we might well apply some epoxy undercoat as well. To ensure compatibility, it seemed to a good idea to purchase Coppercoat’s own brand. The application was done “by the book”, all seemed well and off we set. Come September, a few small white spots appeared on the hull and it was clear that some of the coating had come away. By the following autumn (2011), there were numerous such spots. The boat was eventually lifted in late February 2012 when it became clear that there was a major failing in the coating. Much correspondence with Coppercoat had taken place and, as a “matter of goodwill”, they had supplied 2 packs of Coppercoat. This was half what I had requested and, it transpired, less than half of what was required. To cut a long story short, we were told that it was very likely that the first coat of epoxy had produced an “amine blush” which had prevented proper adhesion of the second layer. No satisfactory explanation for this materialised. Including the Coppercoat itself, we applied 7 coats of epoxy all under much the same, pretty much ideal, conditions. Only the first coat malfunctioned. There was, of course, no mention of the possibility of an amine blush in the directions; if there had been, it may have been recognised and dealt with. As it turned out, about 10,000 (yes, 10.000) delaminated spots had to be sanded out epoxied and re-coated with Coppercoat. As well as a huge amount of effort, there was the cost of a lift-out (450 Euro), 3 more packs of Coppercoat (about £250) plus tools and other materials. To add further stress, when the 3 further packs were ordered from the only Coppercoat agent in Turkey, it transpired that he did not have any. We had to wait 2 weeks for delivery so over-ran our re-launch date and were within one day of incurring further yard charges of 225 Euro for moving our boat so that the one behind could be launched. There is still a likelihood that the whole operation will have to be repeated if the, as yet, untreated areas similarly fail. Coppercoat assert that their epoxy (manufactured by 3M) has had widespread use without problems. However, as far as I know, it was originally made for the treatment of steel structures (such as gas rigs) and so I would be very interested to know if anyone else has experience of applying it to GRP hulls. And if anyone else is inclined to use this product, be very aware of what might happen.
