For over 20 years now I have been wanting to prepare a paper on the
design and manufacture of lightweight pneumatic cloth.  I have the
information; the job needs to be done.  I need to do something about
my motivation.  I might talk to Spencer Chase to see if I can get
some of his!

In summary, the pneumatic cloth needs to be cotton with an even weave
in warp and weft of a minimum of 100 threads per inch.  The coating
needs to be rubber, but am not a rubber expert, and can't specify it;
I need help.  The amount of fillers, etc., is hard for me to say.
The thickness is best measured by the weight increase of the cloth
due to the rubber coating.

Pin holes are allowed but not too many.  This is an odd statement, I
know, but pin holes aren't the be-all and end-all of coating thickness.
The problem with cloth is not how it is when new, but how it performs
after some time.

My paper on force development has had an influence on what a coated
cloth requirement is.  A cloth maker cannot assess the performance of
the cloth in use.  It can be assessed only during manufacture, so a
correlation is required.  He can measure weight increase and use this
as a production measure.

Art Reblitz gives a criterion for the way a small pneumatic collapses
under its own weight.  I agree with that criterion.  (See his bible,
"Player Piano Servicing and Rebuilding".)

Man-made fibres and urethane coatings, regardless of their thickness,
I found to be too stiff, and difficult to glue.  I think cotton doona
material is suited to be coated. [*]  Archer Rubber in Massachusetts
did a good job.  I did visit them years ago on a Friday afternoon --
the factory was open but no-one home.  Are they still there?

I did get involved with the Melbourne factory that, I believe, still
makes cloth for sale on special order.  My contacts were originally
from this place but, sadly, they folded years ago.  I have enough
cloth to do me.

My investigations into the manufacture of this pneumatic cloth have
not been published before.  The paper is half written.  (Note to me:
I must finish this!)  Hope this helps.

Compliments of the season to all you MMD'ers!

Paul Rumpf
Melbourne, Australia

 [* Doona is Australian slang for quilt or blanket.  See
 [ https://www.arrohome.com/blog/doona-whats-behind-name/ 
 [ -- Robbie