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MMD > Archives > October 2001 > 2001.10.04 > 08Prev  Next


Preventing Piano Roll Tearing
By Craig Brougher

I have been reading some good comments about protecting old rolls.
John Rutowsky's comment about the Baldwin tracker was also accurate.
I was about to offer that one, myself.  But the comment I haven't seen
in print yet is, "What is the best way to begin when playing an old
roll that hasn't been played for awhile?"

You might have noticed already that rolls which are torn or prone
to tear on reroll are obviously not wound evenly on the core to begin
with.  If you can remove the left flange, you will notice the paper
edges vary a lot through the wind.  Make sure then that each roll
begins with its paper edges tight against the right hand roll flange.
Here's how:

Hold the roll vertically at its center and rest the right flange in
your other hand, then unwind it 5-10 half-turns with the right flange
down.  You will feel considerable looseness in the paper and then tap
the right flange down on a hard surface while squeezing and releasing
the paper, as well as maybe unwinding it a few more turns.  By holding
the roll firmly while unwinding its right flange, you open the turns
more evenly throughout the roll.  That takes the friction out so the
paper can all be tamped down against the right flange.

If you can get a glimpse of the paper edges at the left flange (or even
sometimes pull it right out of the core) you can watch what you're
doing once.  After that, you won't have to watch.  You'll feel what you
are doing.  You will vary the tension in your roll hand and notice that
it determines where in the roll the turns get loose! by tapping the
right flange, those turns drop against the flange, and you can
straighten an old roll perfectly that way.  What would have played off
the core in  a wandering path will now come off straight, and return
straight.

Don't use rubber bands to store rolls -- leave the roll loose in the
box after it has been played.  A rubber band causes rolls to tear more
than anything else I know of (for several reasons).  The paper should
be allowed to relax.  If the roll has old and stiff, strongly curled
paper, that is the roll you are not going to keep much longer regardless
of your tracker system.  It will break right across the note sheet by
straightening out.

Some people prefer players without tracker systems, but I don't.
I have noticed that almost all tracking systems are better than no
tracker at all (with the possible exception of the Schultz, which on
old rolls is totally worthless from my point of view.  I also "remodel"
them so that they will track).

I have also put new tracking systems on old players that didn't have
a tracker, and they have saved many a roll collection over the years.
Chasing rolls with a moveable trackerbar isn't what I call "tracking."
I call that "compensating."  The roll returns hay-wound just like it
played.  There is nothing to make it straight, so it remains crooked on
the core.  The only time no tracker is better than a tracker is when
the tracker wasn't rebuilt well or doesn't work very well.  Otherwise,
I eagerly recommend a tracker system for playing rolls that won't track
straight.

As far as single finger trackers go, you will notice that they all have
a finger on the left only -- never the right.  That's because the left
is the control edge of a roll.  So when you set your tracking system,
you set it according to the holes closest to the left edge, whether or
not that system has two fingers.  Let the paper and the holes go where
they will at the right edge.

Every tracker has an optimum clearance between the fingers.  Some
require that the paper always touch, and others are "faster acting,"
and need just a hair's breadth of space.  But you must find a narrow
roll and a wide roll to test it with.  When the system rerolls, it
should not favor the right or left flange on the majority of the rolls.
Whichever flange they tend to favor then, will tell you which finger to
move closer to the paper (with a two-finger system).  Usually you will
have to move both fingers together, left or right.

If the paper is always rerolling against the left flange and the system
is a recentering system, like Aeolian and Standard or all mechanical
trackers, then that means the tracker spent most of its time to the far
left.  That means the right finger was possibly too close to the paper
(just the opposite that you might think, right?).  But if the system
just floats on reroll without a return spring or a cutout block, take
almost all tension off the reroll brake first.  Then remember to adjust
the fingers to coax the paper over a little to the right.

The most common misconception in adjusting trackers I have seen is
overcompensation by the technician.  The first requirement is to track
a new roll perfectly, of course.  Then watch what happens to old rolls
and remember that the primary finger is going to be the left finger.
Get the left finger tracking first.  All it takes is just a bare little
"budge."  You are trying to establish not so much a "gap" between roll
edges, but think more in terms of adding or subtracting "tension"
against the paper edge.  Everything  in the regulating of fingers is
determined by the leather you've used, and its seating, cushion, set,
and nap.

In differential trackers with opposing bellows and no valves, they will
act proportionately against each other and whichever side has more
pressure it will favor.  If the system has valve driven bellows, you
can still do this trick as long as the bleeds are correctly sized, but
it's harder, so the tubes need some sort of filter in them to prevent
the bleed from getting smaller over the years.

In Standard trackers (most still don't understand them), the action is
slow, regulated by internal bleeds, for a reason.  They will track some
bad paper because their valves have big bleeds and are "time-sharing"
proportionally on torn edges.  So since they will not swing over fast
(like, say a Kimball), they sort-of "add up" the torn paper, instead of
just ignoring it.

As long as there is enough paper to sense from time to time, and
because they favor right over center, then as long as there is
occasional tension bumping of the differential bellows from a torn
left edge, the Standard tracker won't move very much.  The moment there
are no occasional 'bumps" on one side, the bellows moves very
positively.  So in all, the Standard when rebuilt correctly and its
spring tensioned and slid correctly, will track as well as the best of
them, overall.  I like a Standard Tracker because there are no fingers
to get out of adjustment.  But it is true that curled edges (not torn)
will confuse this tracker.

One last comment about tracking: 90% of rolls are torn on the left
edge, not the right.  That's why a Standard works like it does on most
torn rolls.  But they have to be internally adjusted and tight, and the
crank system and rod support, bushings, etc., have to usually be
replaced and reglued with hot hide glue so it cannot budge sideways as
the rod turns.  You cannot afford to see the cam rod moving even a tiny
bit sideways as it rotates.

Craig Brougher


(Message sent Thu 4 Oct 2001, 15:05:01 GMT, from time zone GMT-0700.)

Key Words in Subject:  Piano, Preventing, Roll, Tearing

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