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I wonder why the pre foam catamaran hulls are often identified by the nick name "egg shells" ?





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The answer is stiffness. This only comes from the thickness of the material. The loads imparted on a catamaran hull are negligble relative to the strenght(tension) of the fibers. The failure comes in compression (Just see Altered as an example) To make a hull stiff enough to stand on or any other non sailing related tortures they go through with a single skin, it would weigh a ton. Cores add thickness without significant additions in weight.

M