your material sounds very nice.

I think that also metal buckets
might work.

I'm looking for similar
buckets to make some
experiments, too.

I made yesterday still more
drawings.

This draft above is quite similar
as I made earlier, suggesting developments
of 'WindstuffEd's 'Lenz' turbine. But if
you will make your machine with skewed
vanes like in 'Gorlov' turbine, you can
using waste materials from the bucket,
make 'the crossflow turbine' inside
skewed, too.

Then still another possibility would be to use
waste material from the bucket to fill
the vanes outside with strips. I'm not
sure, if it is necessary to fill the
leading edge rough shapes
with some kind plastic.
The vanes might work well without
filling, too.