In response to Gary Heckman's question about his Ampico piano rewinding
too fast and about the purpose of nipple #13 in the "Inspector's
Reference Book."

First, nipple #13 has nothing to do with rewinding.  It connects to a
leather pouch attached to the spring on the bottom of the air motor
regulator.  The other end of the connection can connect anywhere to the
treble end of the stack, to receive stack vacuum.  However if the
leather pouch on the bottom of the spring is not absolutely airtight,
it serves no function.

Many Ampico units do not have this feature, as it was added -- or
perhaps discontinued -- in later years.  Its purpose is to slightly
increase tension on the spring, to adjust the tempo during the playing
of loud passages in the music.  When the vacuum on the tracker bar
increases, it slows down the process of the paper passing over it ever
so slightly, thus negatively affecting the tempo.   The majority of
listeners do not notice this slight retardation if the pouch is
lacking, disconnected, or not functioning.

My own Ampico rewinds at a very fast speed and does not tear rolls,
unless the paper is extremely old and severely damaged from age.  The
paper can be so far gone that it is lost cause!  Accept it.  In such a
case rolls will tear at any speed of rewind (slow rewind is worse), and
sometimes they will tear during play.  If the rolls are rare or
valuable, I suggest that you have them copied on new paper.  If they
are common, I save the ends, and some of the boxes and, sadly, use the
fragments of paper to start fires in the wood stove.

The most important thing about rewinding any player, especially fragile
rolls, is the take-up spool.  Especially the take-up spool brake.
Disconnect it!  And save your old rolls.  They may rewind loosely, but
better to tighten them by hand than have them tear due to the take-up
spool brake.  

The take-up spool should spin freely with no binding.  The bearings
should be so well-lubricated that the take-up spool will spin freely
when the lever is set at rewind and the take-up spool is spun by hand.
If it binds, even slightly, rewinding will tear old rolls.

Bruce Clark