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MMD > Archives > December 2001 > 2001.12.27 > 10Prev  Next

Gulbransen "Fishing Pole" Tracking Mechanism
By Craig Brougher

Regarding the mechanical slip-wheel tracking mechanism of any brand,
including the Gully, let me rough these out for anybody who is
interested, and whose tracker doesn't seem to work right.  The
designers all used a long lever to give them plenty of leverage to be
able to move the roll back and forth.

It's the left roll chuck spring that provides the return spring tension
for these trackers.  When the left tracking finger is pushed left, the
tension between the friction wheels is released, allowing the chuck
spring to raise the long lever by unwinding the string.  The string
winds and rewinds on a spindle which is turned down to a small diameter
to give the system enough power to shift the roll.

The correct position of the lever, when controlling a good roll should
be at the half-way point in its travel.  It should also be directly
over the center of the spindle the string pays off from.  On reroll, a
hook of sorts, sometimes with a leather nut adjustment, is provided to
catch the shifter lever motion and in effect prevent the left tracking
finger from being pushed left, and disconnects the drive shaft that
would normally turn the drive wheel (disk).  This keeps the system
static, and in the last position it found itself in just before that
reroll lever was switched into reroll.

The string should be braided nylon cord, as sold in fishing supply
stores, just as Stephen Goodman suggested.  It think they sell it as
trot line.  Any weight test up to 50 lb. is fine.  I use 20 lb.

Here is a number of typical problems one finds in a mechanical tracker:

1. Someone has oiled the slip wheels and/or rotating spindle and
the system needs to be cleaned

2. The reroll hook at the transmission isn't adjusted quite right,
so the long lever flies up quickly at the reroll point, which will
tear rolls on the left flange during reroll.

3. The lever mounting joint in the back of the spool box is broken
and wiggles, preventing good tracking.  It doesn't take but a very
minute amount of lost motion at this point.

4. The lever is not directly over the winding area of the spindle,
and the cord double-winds on itself.

5. The tracking finger toggle wire/wires are either binding in the
wood hole they pass through, or the tracking finger nails are bent,
loose and wiggling, or the tracking finger compass spring under the
trackerbar cover board is gone.  Anything that binds them will prevent
good tracking.  Loose as a goose-- that's good.

6. The tracker system isn't adjusted correctly, after everything is
working properly.

To adjust the tracker, you might have to remove the cover board in
order to watch the left finger or both fingers in some cases in the
double finger trackers.  The left edge of all rolls is the control
edge.  This is the edge that is trimmed to the position of the first
note hole.  The right edge may also be trimmed (and is) but is trimmed
in relation to the left edge trimmer (11-1/4"), and not the note hole
row.  So when you see note holes in the paper splitting the trackerbar
holes on the treble end of the bar, the problem is either swollen or
shrunken paper.  As long as the furthest left hand note holes are
directly over the trackerbar holes in the bass, then that roll is
tracking perfectly.

Whether a single finger tracker or a dual finger tracker, you will
notice an adjuster "loop" in one of the tracker wires that connect the
finger to the toggle.  That loop will be outside of the spool box on
the left, and accessible to you.  Begin with a strong, new roll with
new paper.  One that you are assured will track perfectly.  Later, you
will test the tracker with 6-12 other rolls that tend to tear.

Use a long nose pliers and very gently tension the loop in or out.
It's not so much a "bending" as it is a gentle tensioning.  If you
don't think in terms of bending it, then you will more likely do your
adjusting correctly, because it doesn't take much, at all.  This loop
basically draws the spindle's idler closer to the drive wheel when it
is closed.

If rolls are tearing on rewind on the left flange, then either the
rewind hook is allowing the tension to release suddenly, or the roll is
normally tracking too far right.  These mechanical trackers don't have
a device which would allow them to re-center on rewind.  If the roll is
tracking too far to the right, then your left tracking finger is too
close inboard and needs to be loosened a bit.  Likewise, your right
finger might also be too far outboard.

If your fingers are too "tight" on the roll, it won't track well,
and if they are too loose on the roll, they won't track well, either.
Keep in mind that the left finger is the primary one, and the right
finger just winds up the string-- the same thing that happens when the
left finger isn't being touched.  Good luck.  It takes a little time to
understand it and nobody can help you much there.

Craig Brougher

(Message sent Thu 27 Dec 2001, 15:21:00 GMT, from time zone GMT-0800.)

Key Words in Subject:  Fishing, Gulbransen, Mechanism, Pole, Tracking

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