Query number 2.  I'm having trouble adjusting my one set of
accordion pneumatics.  I have had a hunt through all my Duo-Art
literature and have found only two references to the thickness of
suitable spacers.  They are from Mike Kitner (Vestal Press Technical
Series No. 5, Rebuilding The Duo-Art Reproducing Piano Mechanism)
and Paddy Handscombe (MMD 2006 03 07), archived at
http://www.mmdigest.com/Archives/Digests/200603/2006.03.07.10.html 

They recommend the following spacer thicknesses:

     Handscombe          Kitner           JP
  1/4"  (0.25")      3/16" (0.1875")    0.190"
  5/16" (0.3125")     1/4" (0.25)       0.249"
  7/16" (0.4375")     3/8" (0.375")     0.373"
  5/8"  (0.625")      5/8" (0.625")     0.625"

The third column gives the thicknesses of a set of spacers that a
friend turned on his lathe, using the synthetic material, Syntactic.
Evidently I had come across only the Kitner dimensions at that time.

Using these spacers, I have now recovered the accordions three times.
The first time I used a pneumatic cloth a little heavier than striker
pneumatic cloth, and couldn't achieve the necessary travels of 1/8",
1/4" and so on.  So I added some cardboard spacers to the Syntactic
ones and tried again.  I felt bad about this and so, when I was
reassembling the player I stripped the cloth off again, discarded the
extra cardboard, and used just the Syntactic with some Columbia Organ
Maroon Pouch Leather.  Hardly had I finished the gluing when I read
a comment in MMD by Paddy Handscombe about not using pouch leather
because it stretches.  Well at this stage I decided to hell with it;
I'll reassemble the expression unit and see how things go.

Not very well, was the result.  Roughly, the maximum travels I can
get are almost 1/16", 7/32", 3/32" and 7/16", instead of the necessary
1/16, 1/8, 1/4 and 1/2 inches.  I managed to get 7/16" out of the
notional half-inch gap only by screwing the three hex- and flat-headed
adjusting screws up so much the that valve stems protruded into the
space occupied by the 1/4" accordion.  The stems started pushing up the
felt bumpers of that accordion, thus reducing its travel.

I'm planning to use striker pneumatic cloth for my fourth attempt, but
if anyone can point out that I'm doing something dumb, I won't be glad,
but I'll be grateful, to hear about it.

I should mention that the existing felt bumpers are in almost new
condition; this player action has never had very much use.

John Phillips in Hobart, Tasmania