Richard Edlin, boat builder and designerMatakohe, North Auckland, New Zealand
Overdrive

Overdrive Continued - pg3

The coamings are narrower than the original plans for increased cockpit floor area. Lifting the cockpit seats reveals a fridge to one side, deck storage under its opposite number, while the hydraulic system and gas bottle reside under the rear helm seat. Access forward is either over the flat-topped cabin, or via the expansive trampolines. The Ferrari tramp material - nothing to do with the car manufacturer, it's French - is noticeably stiffer than the usual Luminite or Fabloc, and as it's stitched and welded, it should last longer.

The rig is a non-rotating fractional with twin swept spreaders stayed to the main hull, and cap and masthead shrouds to the floats for extra support. The radiused aft beam carries the main traveller, with the sheet directly under the boom even when running, so there's no need for a vang. Rupert King didn't want a boat full of sails, and there is no provision for overlapping headsails. The wardrobe consists of main, 100% jib and masthead gennaker; a storm jib will be added for offshore. The aluminium boom is temporary; Rupert plans to add an open-topped, foam and carbon boom to contain the flaked mainsail and provide a water collector - a neat idea.

With offshore use in mind, King was not overly concerned with weight minimisation - construction is solid. Predominately strip-planked cedar, the main hull is 12mm with 600 gram double bias (DB) glass inside and out. The floats are 10mm cedar with 430 gram DB inside and out, and foam top hat stringers for longitudinal stiffness. Beams are laminates of ply, carbon fibre and DB cloth, and the cabin top is a sandwich of ply, glass foam and glass, with selected carbon reinforcement. The chainplates are carbon with foam knees. Resins were all WEST system. Daggerboards and rudders are built in cedar and macrocarpa, with glass and carbon reinforcing. They are all the same dimensions and are interchangeable in case of damage. Although it adds cost and complexity, Edlin believes float-mounted rudders are essential for high-speed control. The helm has three gearing ratios, easily altered by a bolt per side. As tested the helm was set up for maximum manoeuvrability, at a cost to steering effort. The two lower gearings increasingly reduce steering effort at a cost to rudder lock. The lower gearings will be used offshore to give the self-steering an easier time.

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