On the subject of paper organ pipes, I was able to build a diapason
from cardboard tube, about 1/8" wall thickness.  I sealed the inside
with sanding sealer, several coats.  I was surprised that it actually
sounded pretty good.

I know that Hupfeld had some ranks in their orchestrions that were made
with cardboard resonators.  Maybe they were trying to achieve a certain
tone quality that is only found in paper or cardboard.  Does anyone
know more about the cardboard pipes from Hupfeld?  It's nice to know
that there are (almost) endless possibilities in pipe building.

Brian Smith