: That works for a model test, but won't yield a very useful boat.
: There are a few ways to change the parameters such that the
: design will still work.

I built a Great Auk scaled to 5/6 (83%) and it's a fine boat for the small
person for whom it was intended. I can even fit in it myself, though I'm
twice the weight that its design displacement suits. And taller, so it's
pretty wobbly for me, and sits low in the water, but does go very fast
owing to the narrow beam and low wetted surface area. For my daughter,
(and my wife has used it too) it's a great boat. That's uniformly scaled
in every dimension.

But children aren't just scaled down adults, and for a performance boat
for a more advanced paddler than she was 9 years ago, I might want to
scale length, beam and depth separately. That's also easy for something
like a stripper where you are working from offsets, but for scaling a stitch
and glue boat, it's a lot harder to scale non-uniformly. For uniform scaling,
though, you can do it just as easily with S+G. My own boat was scaled
by converting from the published offsets to metric, pretending that an
inch was 24mm (instead of 25.4). So that's maybe 95%. The deck was
built as a more rounded strip deck, based on the original offsets. That's
also a fine low-volume boat for short multiday trips.

Andy