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MMD > Archives > December 1999 > 1999.12.26 > 04Prev  Next


Restoring Gulbransen Action Stacks
By Craig Brougher

I second the motion to restore a Gulbransen.  Good player pianos are
becoming more rare by the year, and they are never going to build them
again.  What we have today is more than there will be tomorrow.  In
just 24 hours time, several dozen more player pianos bite the dust,
and often because of novices who have tried and failed to make them
play, particularly Gulbransens.

There are two legitimate ways of restoring Gullys.  You can either
break them apart and restore them back originally, or you can gasket
them.  I endorse either way.  I agree with rebuilders that bring the
piano back to life and allow it to be restored again in the next 70
years or so.   But I give the edge to the rebuild that gaskets them
together.  I forego originality in the case of the Gulbransen for
this reason:

When Gulbransen originally built these throw-away stacks, they were
replaceable for $32 with the old stack.  I was told they fueled their
boilers with them, which I believe.  The glued-together units were,
for all practical purposes, unrestoreable at the time.  Now, given
another 50-70 years of freeze and thaw, hot and cold, shrink and
expand, and the stacks will break apart fairly easily.  But when
relatively new, they didn't.  Likewise with a new coat of glue in
everything.

So if you have only _one_ valve that doesn't come up to specs, and
you've glued them back together, you are going to have a mess to clean
up.  The best way then is to simply cut new valve pneumatic parts and
make new ones, because you cannot put a block of wood against them and
rap hard, and have them fly off!  New hot hide glue will tear the wood
before it will break its joint.  What you have to do then is gasket
each valve pneumatic.

It is not a project for a beginner, and I really want to stress that,
because once somebody says they can do it, many novices will attempt
it, not in the least aware of what they are getting into, or the
problems they should expect to encounter.  For example, the least of
their worries are the blind 5/32" pouch holes they will have to join
without clogging with glue.  But if they don't use hot hide glue, their
work will be a complete failure and made unrestoreable after that.  Yet
with hide glue, they tend to use glue that's too thick and which clogs
the small holes, partially or fully.

Another problem encountered with Gullys is that some chests were edge
lamination boards made of maple scraps.  When the stack is knocked
apart, this invisibly loosens a portion of the original butt joint,
but it may not show up until winter months when the boards shrink.
Then two or three notes play down all the time, or play once and then
stay down.  When you've done enough of them, you are able to anticipate
these things in advance.

Also, gasketed Gullys tend to loosen up in the winter, unless its bolts
are under spring tension or some other way is provided to maintain the
equivalent of spring tension.

The striking fingers of a Gulbransen are hinged with cloth.  If they
come back with the same old material present, it's a good bet that it
won't last long.  If you have a Gulbransen rebuilt, get a guarantee
with it that you know you can trust.

If your instrument pumps easily, tracks well, and plays hard, then it
will probably outlast you.  If you have to pump fast to play it, it
will just keep getting more leaky with time.  If you need a suction box
to pump it, something serious is wrong.

If any player piano cannot be restored back with the foot pumps and
make a comfortable, relatively easy-pedaling player before the suction
box is added, it has too much leakage.  Most players will restore tight
enough to pedal and have fun with.  The Gulbransen was reknown as an
easy-pumping player piano.  (There are exceptions, by the way!)

Craig Brougher


(Message sent Sun 26 Dec 1999, 19:14:46 GMT, from time zone GMT-0600.)

Key Words in Subject:  Action, Gulbransen, Restoring, Stacks

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