Sick of Silic

During the major refit 2 years ago, I had the opportunity to review the antifouling situation. (the coating on the hull to prevent the growth of weed and barnacles etc) The existing  ‘coppercoat’ treatment was both disappointing (maybe I expected too much) and coming to the end of its effective life, so I thought it was maybe time for an upgrade. A new product by Hempel, called ‘Silic One’ was getting rave reviews in the yachting press and seemed, from the hype, to have all the answers. The antifouling promised to be effective for several years, only ever needing just lightly hosing off (it would be stripped by power washing) and it is, apparently, easy to augment with no additional surface preparation. The principle is that it is very slippery and anything that tries to stick to it will just wash off with the passage of water when underway. The treatment on my propeller works on a similar principle and it is very effective.

What was not to like? I have now found out!

The hull preparation demanded the complete stripping of the existing coppercoat, right back to the epoxy substrate which was an arduous job. There was then a complicated sequence of applications with a final ‘tie coat’ before the actual silic covering could be applied. Additionally, the temperature and humidity is a critical factor and, over the winter, it was necessary to erect a ‘tent’ around the hull to achieve the correct environmental conditions. You will have seen from previous blogs that the launch was frustratingly delayed into more benign climatic conditions and, had I known, the costly ‘tenting’ would actually have been unnecessary. What we had also not properly thought through was the fact that the inaccessible patches where the supporting cradle pads bore on the hull had prevented the complicated preparation and covering process in those areas. In the event, the very craning process when lifting back into the marina, scuffed away the delicate surface where the strops bore against the hull. All in all, the whole exercise was compromised, but by that stage, I was committed and had little choice. Maybe the shortfalls could be corrected at the next ‘lift’ – I thought…

Initial indications were encouraging as we had a fast passage to Dun Laoghaire suggesting that the hull was super clean. We left Hejira in the marina near Dublin for several weeks and observed from other vessels, that the general level of fouling around the marina was pretty bad. Our onward passage should have washed the hull clean, but it became evident that the log impeller was seriously ‘under reading’ despite thoroughly cleaning the paddle wheel which suggested that the hull had some growth. My brief icy dive off Oban cleared the fouling from the hull around the log opening and it subsequently began to read correctly, but it all indicated that the Silic was not performing as well as expected.

The lift on Monday 17^th of February 2025 was to reveal the extent of the problem and I was resigned to making whatever decisions were necessary to ensure several years of easily maintained, fouling free sailing, possibly away from easy access to marina facilities.

Unfortunately, that morning, having moved Hejira to the waiting berth as stipulated by 08.30 for the promised 09.00 lift, by 10.00 there was still no activity apart from the staff debating moving other yachts to make a place for Hejira. Expecting to ‘drive’ Hejira into the crane dock, we were told that they would ‘warp’ her in and our help was not required. With no sign of any imminent activity, we decided to leave the marina to it.

It came as a complete surprise when, late afternoon, I had a call to say that Hejira was still in the slings as she had slipped when they were trying to block her off. The staff blamed the Silic coating as the supporting pads could not make a purchase against the slippery coating on the hull. I had arranged for Chris Murch from Hayling Yacht Services to be in attendance and he set about stripping the Silic from the area of the support pads and abrading the hull. Any notion of retaining and repairing the Silic coating was now abandoned.

The following morning, the yard staff were still not happy and insisting that they put Hejira back into the water as they could not safely ‘block her off’ and there were other yachts with disgruntled owners, scheduled to be lifted. I was not happy as she had been ‘blocked off’ ashore at Northney half a dozen times before, even withstanding over 100mph winds, unattended over Christmas 10 years before. I ended up having to speak to more senior staff, and eventually the Marina Manager, explaining that Southerlies were designed to safely sit on their grounding plates when they dry out on the sand and mud between tides, without supports. I just could not understand their issue when they routinely deal with yachts right up in the air with 6-foot fin keels. I suggested that further areas around the grounding plate would be stripped of the slippery Silic and additional blocks could be used.

They finally relented and she was ‘blocked off’ ashore late morning having spent 24 hours ‘in the slings’, now hopefully safe but with the manager labouring the point that they would have to carry out daily checks…

So, apart from the other jobs like replacing anodes, a seacock and tidying some hull windows, we will be stripping the Silic off the hull and applying the best traditional, hard, antifouling available. We should then be able, in future, to simply lift, wherever we are in the world, and have the hull pressure washed as necessary and returned straight back into the safe embrace of the sea.

The Hempel Silic One may be a fabulous product and the antifouling Nirvana for power boats which travel fast enough to purge their hulls of growth, but for a sailing yacht, particularly one as sedate as portly old Hejira, it is probably not the answer.

Little wonder that I am ‘Sick of Silic’!