Is it mainly the difficulty in forming compound curves that stops more
aluminum yachts/cats being made? I see lots of powerboats nowadays
going over to 'plate aluminum' construction with 1/4" aluminum being
used rather than the really thin gauge stuff used on small runabouts,
these boats looks strong with many of them having water ballasted
keels, and fully sealed compartemtns under the floor with fully welded
bulkheads giving many small water tight compartments and incredible
strength.

It seems to me that with this sort of approach you could build some
incredibly strong and lightweight cats... is this material just too
light? Is it the noise that turns people off more?

Just curious,
Shaun