Mechanical Music Digest  Archives
You Are Not Logged In Login/Get New Account
Please Log In. Accounts are free!
Logged In users are granted additional features including a more current version of the Archives and a simplified process for submitting articles.
Home Archives Calendar Gallery Store Links Info
MMD > Archives > August 2000 > 2000.08.19 > 04Prev  Next


Rebuilding Standard Pneumatic Co. Air Motor
By Paul Manganaro

In response to Julian Brook's inquiry concerning gaskets on a Standard
air motor.  Early Standard air motors did come from the factory with a
leather gasket holding the five pneumatics on.  The leather used was
rather thick, more on the order of packing leather than pouch leather.
This practice did not last long into their manufacturing procedures.
Aeolian used gaskets made of pouch leather to glue most all the note
pneumatics of their Duo-Arts.

In either case, I myself, as well as all of the restorers I know, do
not use leather gaskets when restoring these player units.  This is
debatable.  I would encourage you to use hot glue to reattach the
pneumatics in any case.  This insures the rebuilding of the air motor
the next time it has to be redone.

I must make reference once again to my friend Adam Lowjewski, a great
fellow who is no longer with us.  Adam taught me in 1975 how to
restore wind motors.  He said that leaky wind motors use up a lot of
air and if I wanted to get a player to pump well I'd have to get the
air motor right.  The ultimate test of a wind motor's efficiency is
to block the supply fitting and turn the crankshaft backwards.  If
your motor is 100% tight you will not be able to turn it backwards!
At all.  (This test does not work for Lauters.)

This test frustrated me for some time.  If you try this test on your
own player you will probably find the air motor is easily turned
backwards.  This test was the first thing that raised my awareness as
to the factory's use of shellac in every port and channel.  I've heard
that Art Reblitz is a big believer in sealing every port with shellac
to get the actions efficient.

I seal the inner chambers of the air motor with shellac.  I use button
lac made by Moser's, available from Woodworker's Supply.  I mix it to
a consistency of molasses.  It takes a few days of setting and
stirring to get this consistency from the flakes.

After the channels are sealed I tape a piece of sand paper onto quarter-
inch plate glass and resurface the wind motor's face.  (Always number
the valve guides which are attached to the motor face.)  I do the same
with the slider valves.  I then re-graphite the face and the slider
valves.

I can explain what I do to get the graphite into the wood but I have
been using a container of extra fine graphite powder I bought from an
old guy a long time ago.  I don't know if such a fine powder is
available now.  The graphite is mixed with alcohol and rubbed across
the grain initially to fill the pores.  (John Tuttle was right when he
said sharing this information is not going to get anyone to take
business away from us!)  Then dry graphite is rubbed with the grain.
I also re-bush the air motor arms and re-graphite them.  I spend at
least eight hours rebuilding a virgin air motor.

Grades of Single-valve Standard Pneumatic actions

I thought I'd like to share this information for the Archives.  In my
experience restoring players I came to the conclusion that all Standard
actions were not equal.  In handling so many actions I noticed the
following: As a thumbnail sketch I believe Standard turned out three
grades of mechanisms which on the surface appear the same.  This
information will become less valuable as time passes, because once a
skilled craftsman replaces every bit of leather in a mechanism and
reseals all the wood the finished product will be the same, but this
information was valuable to me when I was turning out great numbers of
finished products.

The lowest grade Standards had escutcheon plates for play, reroll and
tempo with whitish backgrounds and black pinstriping painted on.  These
mechanisms were installed in lesser makes of pianos and never had a
cover over the air motor's slider valves.  The mid-grade Standard
mechanism had simple brass escutcheon plates with black pinstriping
etched into the metal.  The highest grade mechanisms had brass
escutcheon plates with lots of embellishments especially notable on
the tempo plate.  Many of these mechanisms had transposing tracker
bars and a plate in the spoolbox that said: "Artist Record".  These
mechanisms always had a cover on the face of the wind motor.

If you are a restorer and have a few players around you may want to
pick up a wind motor from the lower quality and the highest quality
and take notice as to the weight of the wood itself.  Upon close
examination you will find a higher grade of wood was used in the
better mechanism, as well as bushing cloth behind the front valve seat
of the valve and a higher quality transmission.  I think a better
grade of leather was used in the valve and more shellac was used to
seal the channels.

The higher grade players always pumped very well after I restored them.
I have learned this after restoring almost 450 mechanisms to date.  If
you doubt the number call Bob Streicher; he sold me supplies.

Paul Manganaro


(Message sent Sat 19 Aug 2000, 05:02:41 GMT, from time zone GMT-0400.)

Key Words in Subject:  Air, Co, Motor, Pneumatic, Rebuilding, Standard

Home    Archives    Calendar    Gallery    Store    Links    Info   


Enter text below to search the MMD Website with Google



CONTACT FORM: Click HERE to write to the editor, or to post a message about Mechanical Musical Instruments to the MMD

Unless otherwise noted, all opinions are those of the individual authors and may not represent those of the editors. Compilation copyright 1995-2024 by Jody Kravitz.

Please read our Republication Policy before copying information from or creating links to this web site.

Click HERE to contact the webmaster regarding problems with the website.

Please support publication of the MMD by donating online

Please Support Publication of the MMD with your Generous Donation

Pay via PayPal

No PayPal account required

                                     
Translate This Page