Luc Casaer is a Belgian with a flair for designing row/sailboats with a traditional shape. ‘Doryplume’ his 14’ 11” row/sailboat is based on the venerable American Swampscott dory and ‘Joilli Couer’ (which means "The Charmer" in French) a double cabin two mast, center cockpit sharpie comes to mind. Of interest is Luc’s take on leeboards and a simple sail rig for a canoe, a guide boat or a small rowboat where the owner is looking to modify an already existing vessel for modest sailing.
Luc’s leeboard clips over the gunwale and with a large turning screw wing nut that cinches the board tightly to the side of the boat. Luc points out that the sides of the vessel must be reinforced to accommodate the stress of the lateral pressure while going hard to windward. Many open boats to be modified with this arrangement will probably never point well to windward due to hull shape with any efficiency anyway. Where Luc shows the added lower sheer plank stress strips on the boat, one could built this into the board clamp system to spread out the stress with out adding to the vessels structure. The board will probably stay on one side no matter what tack the boat may be on. Thus some versatility would be given up, but one could ‘ease’ to windward using an oar or use a paddle in place of a rudder. Off the wind, one will pick up sailing stability and enjoy a ‘hang onto your hat’ grin! Luc’s design shows a robust leeboard (Online Conversion can get you from Centimeters to what ever measurement works for you) that may need to be resized for your use. Remember to shape the board profile so it is relatively flat on the side facing the boat, and outward curved on the face away from the boat.
Adding a sail to an open boat is a challenge and Luc’s solution is to use a sailboard rig. His innovation is to add a horizontal sprit to the raised clue. Using a downhaul one can shape the sail variously to improve efficiency depending on one’s angle to the wind. Luc used an adjustable fishing rod to make the horizontal sprit. The luff of the sail is attached to the mast with sewn in Velcro strips.
Luc states in an article from “Messing About in Boats”: “In my opinion this rig has many advantages on a small boat over the common boomed sail we all know so well: A clean airflow in the lee of the sail; because of the high clue the sail is not pinned on the water in case of a knockdown; built-in downhaul, which I find the most striking advantage verses the boomed sail. It eliminates rolling and puts no strain on the sprit, which is in compression only so all the gear can be light. There is no need for a sheet traveler; you have good control of the sail shape, and there is no hardware, only a few pieces of plywood (the mast step), bits of rope, and two blocks.” The sail shape can be maintained if one ‘dips’ the sprit on each tack – or if not – though the sail shape may appear spoiled, it will still work if one only adjusts the downhaul.
Sad to say Luc Casaer the historian, archeologist, small boat designer and builder passed over the bar in October of 2001.
Attachment: Luc Mod.gif (Downloaded 97 times) Last edited on Tue Feb 13th, 2007 04:07 pm by Thom V |
