Brian Nystrom ) writes:
Most people wouldn't understand these numbers, so they're rarely published.
what the sales literature had were vague statements like "for weekends" or
"for multi-day trips". I think they should be more spacific and say "this
boat is designed to perform best with a load between 250 and 500 lbs". I
don't see the value of interior volume since its more important to know
how much the boat will float the size of what it will hold. Room sizes are
more appropriate to buying houses which don't have to float their
contents.
If you were looking at plastic boats, that's typical. There are a few out there
that use better materials that are more distortion resistant (Prijon, P&H), but
most polyethylene hulls will distort due to heat and/or pressure. They will
usually return to shape if left out in the sun.
I was careful to distinguish between design weakness and temporary
distortion. I've seek a kayak come off a trailer after a long trip with a
big dent in the side which will strighten out. No, the flat spot on the
chined boat was due to the material being too thin. Housing standards
specify the span beteen joists for plywood of a given thickness. There are
similar standards for boats from insurance associations and naval
architects (eg military), and guidelines such as David Gerr's "Elements of
Boat Strength" of which our public library has a copy. The hull design
programs I've seen don't cover "scantlings", but do cover a lot of
other things like shape, initial stability, capacity, resistance, etc.
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