Those are all very fine formulae for tubing players, however, if
someone is not in my situation with several thousand feet of tracker
tubing sitting in boxes of 500' spools, they should purchase 200' for
a normal player and you may need more after that.

Your formulas work to an extent, but let us remember that in the
center there are a certain number of lengths that are the same.  This
is why adding a half inch in increments does not work -- How far your
tubing goes onto the tracker nipple;  Whether the tube has to go around
this or that to fit through the strap; do the tubes lay flat enough not
to push hammers up when stack is in place?

These are all considerations that will complicate your formulae.
There is also the possibility of tubing to sustaining pedal pneumatics,
pneumatic cut-out, governor bypass, soft treble and bass which are not
always 7/32" tubing.  Plus, for testing purposes, I always need a
couple of 4' lengths or so for testing pouches, blowing up pouches to
regulate valve travel.

Also I find that I tube liberally, and when done I arrange tubing to
avoid getting in the way of piano action.  In doing so I strap it all
into place and usually find I must trim some of the lengths by an inch
or so before they will go together with other tubes and fit under the
straps and such.  I would rather do this than have to lengthen tubing
that was too short.

My idea is to always buy more tubing than you think you need because
you probably will have to order more if you don't.

D.L. Bullock    St. Louis
www.pianoworld.us