Air-O-Player Tracking Adjuster
drawing by C. H. Short, August 23, 1917
by Robbie Rhodes

airOplayer2b.jpg (63 kb)

During several months in 1917, Mr. C. H. Short, of Pomona, California, attended the Danquard Player Action School in New York City, where he enjoyed making detailed drawings of player piano roll tracking mechanisms.  The illustration above is from a photocopy of Mr. Short's 3-ring loose-leaf notebook. (The location today of the original notebook isn't known.)

A short article in Music Trade Review circa 1918 says that Mr. Short was the 152nd Danquard graduate and was considered "one of the most studious graduates that has ever received a diploma from this school."  A few of the drawings in his notebook are dated in 1920s in New York, which hints that Mr. Short returned to Danquard for an unknown period, perhaps to teach.

I recently asked a retired local school teacher about him, and I learned that in the 1950s Mr. Short was still active maintaining and tuning pianos in homes and schools nearby Pomona and Claremont, Calif.  When he retired his practice was assumed by master technician Francis Mehaffey of Pomona Valley PTG.

This 1917 description of the Air-O-Player player piano action and the tracking mechanism operation is given by Mr. Short.  Note that only the pneumatic on the right moves the spools.  The pneumatic on the left operates a locking device.

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1. Tracking device: manual mechanical tracker adjuster, also manual mechanical pneumatic tracker adjuster.

2. 5 point pneumatic motor.

3. Action.  Single valve, vertical.  Bleeds are location in valve stems.  To get at, remove valve units from front of action and take out the valve stems.  To get at this valves, unscrew two screws on top of valve unit, take out atmospheric seat and valve.

4. Lost motion between player and piano action taken up by dowels in rear of player action, or preferably bo a device on each pneumatic operated by a screw accessible from the from of the player action.  This screw is located in the pneumatic lug.

5. Players attacks the piano action against the under side of the wippens.

6. Hammer blow regulation and checking of the pneumatic taken care of by device on the piano action.

7. Top action exhausted from treble end only.  This is not a divided action.

Bottom action

8. Center driven exhausters.

9.  Center connected treadles.

10. One equalizer.  No crash valves.

11. Two governors, one for motor, one for top action.

12. Bottom action: Indirect type.

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Manual Mechanical Pneumatic Tracking Adjuster

Tracker control in key slip.  The left tablet, when pressed down, will cause both pneumatics to collapse.  The right tablet, when pressed down, will cause the left or locking pneumatic to collapse, releasing the right pneumatic, allowing the springs on the music roll and take-up spool shafts to pull it [the right pneumatic] open.

Plate 26 - Normal position, right pneumatic about 2/3 open.
Plate 27 - Both pneumatics collapsed, throwing spool shafts to the left.
Plate 28 - Left pneumatic collapsed, unlocking right pneumatic, allowing springs on music and take-up spools to pull it open, at the same time shifting the spools to the right.

airOplayer_danquard.jpg (15 kb)

Mr. C. M. Short,
420 Columbia Ave.,
Pomona, Calif.

Dear Mr. Short:-

Perhaps you commence to think by this time that I have neglected or forgotten you, and do not intend to answer your letter of Jan. 26th. It is not so.

As there was not any information needed, and as I have been pretty busy, I just laid it aside for a while. It is very interesting to note how you took care of this very leaky player action, and made it as it never was before, but what a shame it was that it tickled the poor people to death. I have been wondering how you managed to get your pay, and also if they had you arrested for tickling them so hard.  Certainly the Civil authorities ought to look you up if you do such tricks as tickling people to death, ha, ha.

Well anyway, old scout, I am glad that you appreciate the knowledge gained at the school, and that you are making the best use of it. I wish to say this, that you was one of the best students, most attentive, most studious and easiest to get along with that I have ever had, and when I get hold of a fellow like this, I certainly appreciate it. I still remember the very hot times we had while you were here. I get a letter from Immeln occasionally and he is doing work on his own hook. I think he got a very rotten deal from those people he worked for.

My best regards to you and yours, and prosperity and good health.

Cordially yours,
Geo. E. Martin


P.S. Sam also sends his best wishes.

06 April 2003