Hi All,  A recent posting stated that the volume of air required to
collapse a pneumatic was the length times the width times the inside
distance between the pneumatic boards at the open end.  In truth it
is one-half that because one of the cross sections is a triangle,
not a rectangle.

Additionally, it stated that the only air flow after collapse was
due to the bleed.  Actually most all pneumatics leak through the wood
even if they have been sealed because the wood is alternately expanding
and shrinking with humidity changes and the pores or grain of the wood
is difficult is not impossible to seal.  Also the glue joint between
the deck and the upper pneumatic board even if perfect when rebuilt
may develop leaks.  The above comment about the pores of the pneumatic
also apply the deck, valve chest and pump pneumatics not to mention
the pumps valves etc.

If after assembling striker pneumatics on a deck you collapse a
pneumatic and fill it with smoke while opening it, then seal the exit
with your finger or hand and then try to close the pneumatic, you will
see there will likely be leaks between the pneumatic and the deck as
well as the seam between the boards and the cloth.  If you are testing
a pneumatic that has been used for a year or so, as detailed above,
there may be leaks in the folds of the cloth also.

Best to all of you out there,
Allen Ford