Sure you need to verify that hull weight is close to design spec. But don't forget that hull hogging, sagging, twist and water infiltration can cause inner/outer  skin separation.These should also be analyzed for maximum benefit before any expensive restoration of a cored hull.


Minimizing the weight and bend/flex in equipment is essential to sports like sailboat racing, bicycling, windsurfing, skiing, hiking and snow boarding. the lowest weight and and highest stiffness will produce top performance when horsepower or effort is limited.


Back when the poly windsurfer came out in 1980 it was possible to get the thing up on a plane in a stiff breeze. When the industry developed  kevlar light weight hulls the weight went from 45lbs to almost 30lbs. In addition to losing 33% weight, the new contruction created a much stiffer hull. The new windsurfer was easier to water start and accelerate onto a plane with identical sails and wind speed.  The most incredible benefit was the ability to pop across the top of waves with no loss of speed. Sometimes these stifff light hulls would actually accelerate as you popped across waves or chop because of the reduced drag. The original windsurfer with its flexible hull was losing energy/speed as it flexed up and down the waves. The new kevlar composite was the ultimate validation of light stiff efficiency.


Sure a stiff boat of a given shape and weight will pound more than the flexible one. If you want the smoothest ride through rough water get a submarine. If you want a heavy deep v boat, then plan on bringing more fuel.


Stiffness is the rigidity of an object — the extent to which it resists deformation in response to an applied force. The complementary concept is flexibility or pliability: the more flexible an object is, the less stiff it is.


If the outer and inner skins have seperated from the core, the monocoque structure and related strength is lost. Even if the core has not absorbed water, the hull has been structurally weakened.



******  Coming soon******  A full explanation of our nondestructive in shop method to measure/evaluate old whalers for weight, delamination, bend and twist. With this data we compare the results to our test standard.

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