Davits for Supermaramu
Hi y'all, We are now , at last, somewhere in Scotland where I hope we can upload some photos onto the Amel site--most of the place we have been to recently have had very weak signals. First of all, let me give credit where credit is due---to Roy Benveniste and his late wife Toni. It was on their SM, Excalibur, in St Lucia in 2003 that we first saw the davits that he had designed. I pondered all kinds of davits for another 6 years and then we came across Excalibur again, in St Thomas, now owned by Jorge and Isabel Zlatar, from Vina del Mar in Chile. They kindly let me crawl all over the davits and take measurements. We returned to England and this past winter I had the davits made by Cooney Fabrications on the Hamble. Three problems arise with the design of davits for an SM. 1. The sloping stern is not the strongest part of the boat 2. The slope of the stern means that the davit arms have to be quite long 3. How do you stop the dinghy, when hoisted, from swaying from side to side?
Roy's design involves two simple S/S davits whose feet slot onto fittings on the gunwale. The davits are demountable and fit into the lazarette. The clever part is that the weight of the davits and dinghy is not taken alone by the feet on the gunwale . Instead, there is a simple cross bar between the davits and where the cross bar ( which can also be demounted) meets the davits there are two eyes on the davits. To each eye is attached a bridle made of Dynema which, in the form of an upside down Y, is in turn attached to the top of the mizzen. In this way the weight of the davits and dinghy is taken by the bridle and the mizzen. I think I am right in saying that Excalibur has raised her Avon rib, ( weight about 70 kg, 154 lbs) plus her 15 hp outboard ( 35kg, 80 lb) on the davits, though Roy did tell me that if he was on a big passage he would stow the boat on the aft coachroof. We have a lighter rib which I cannot recommend highly enough. It is now made in China and sold in the UK by Ribeye. We bought the Hypalon version.It is a copy of the NZ Aquapro, aluminium hull, 3m10, and only weighs 54 kg, about 110lb. Very stable and dry( significantly more so than the 2m80 version--those extra few inches mean everything, as the actress said to the bishop). We do not raise it with either of our outboards attached. ( We use a Yamaha 2hp 2 stroke wherever possible--it only weighs 10kg, 22lb and is a gem. For longer trips we have a Tohatsu 9.9 hp, also 2 stroke, which weighs 26 kg, 57lb. This we raise with a dinghy davit we had made- far better than trying to raise an outboard on the mizzen) We have made two modifications to Roy's design. 1. Our davits are not just seated on the gunwale but also are attached to the rail via a collar with a nylon bush. This makes the whole system much more stable and takes any fore and aft strain off the feet of the davits. 2. The outboard ends of the davits extend to cross over the outboard hull of the rib. This allows you to sweat the rib up tight to the davits.I think this is critical in reducing any sideways motion of the rib.Once we have raised the davits we also tie the two handles on the inboard hull laterally to cleats on the davits.C'est tout.Even ageing sailors like me ( 63) and Judy ( 21 and a bit) can raise the dinghy easily.
The real test---how do they work at sea? Well, we left the Hamble and since then we have sailed 1,700 miles in up to 40 knots in open sea, always with the rib in the davits and totally secure without any lateral movement ( and this includes rounding the Mull of Kintyre 3 days ago with 35 knots from astern meeting a 5 knot ebb.....I thought it was the 5th August with a favourable tide---it turned out to be the 12th August, one of hazards of the life of a sea gypsy...) I believe we will keep the rib in the davits in any sea. That has certainly been achieved by other friends on other boats and I think this design allows the same security.
At the same time as we fitted the davits we scrapped the original rope across the stern and fitted a proper s/s pushpit with an opening gate-see pictures also. Huge improvement, both in looks and safety.
If anyone is interested I can also post all the dimensions. Fair winds, Ian and Judy, Pen Azen, SM 302,Troon ( the marina, not the golf course), Scotland(photos attached and hopefully to be uploaded)