Hi All,  Over the past couple of months, I've come across three
player pianos that had new tubing installed less than ten years
earlier.  Each of them had at least one problem that was directly
related to the new tubing.  One would think that replacing tubing
is perhaps the easiest job there is when it comes to fixing a player
piano, and, in my opinion, it is.  However, from what I've seen,
people often neglect to consider what happens to the tubing after
it's installed.

Primarily, there are two forces that will effect tubing after it's
installed.  They are 'gravity' and 'pressure'.  Both of these
forces work fairly slowly, and it might take a few years for them
to adversely effect the position of a piece of tubing.  But, if they
aren't considered when the tubing is installed, there will be problems
in the future.

The easiest way to prevent problems is to think about how the
forces of gravity and pressure will work on a piece of tubing.
Simulating these forces is relatively simple.  All you need to do
is push on the tubing in the direction in which the force/s will be
working and watch what happens.  In many cases, it will be found that
part of the problem has to do with using too much tubing.  When it
comes to re-tubing a player, more is almost never better, and many
future problems can be easily avoided by shortening the length of the
tubing.  A properly sized piece of tubing should fit between the two
connection points without being stretched.  Also, the tubing shouldn't
sag unless it's purposely designed to do so.  (An example is the
trackerbar tubing in the Gulbransen.)

Another way to prevent future problems is to use tubing that is the
same as the original tubing.  That may sound like a no-brainer, but
things like wall thickness are just as important is using tubing that
has the correct inside diameter.  Remember, player piano tubing is
specifically 'under-sized' to fit correctly.  In other words, tubing
that is sold as 7/32" I.D. tubing will fit perfectly on a connector
that has an outside diameter of 7/32" because the actual I.D. of the
tubing is slightly less than 7/32".

Musically,
John A Tuttle
Player-Care.com
Brick, New Jersey, USA