The Design
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  • By calculation, the test weight (weight necessary to sink boat) should have been 1650 lb.
  • The actual test weight was 1780 lb and the boat did not actually sink. (Perhaps the gunwale was trimmed a little high)
  • This works out to 534 lb max safe load. The USCG rules allow 4 persons without motor, but just 3 with a 2 hp motor.
  • The goal was to keep the transome out of the water when loaded with 400 lb to make rowing easy.
  • The wide transom above the water was designed to provide lateral stability
 
The mold lines are carried up to a common reference plane. The top longitudnal curve is the edge of the boat. It is important to have enough room at the top of the mold for vacuum bagging so there is 6 inches at the bow and extra elsewhere.
   
This is a little more of an isometric view
   
The aspect of interest is that the waterline drawn is for a 400 pound load. In order to make the boat row nicely I wanted a smooth waterline at this weight and to have the transom out of the water.