Bill Edgerton asks about how to regulate an Ampico model A.  The
most important thing is the regulation of the spring pneumatics.
By adjusting the nuts one can open or close the amount the spring
pneumatics are open which makes them either stronger of weaker.
I think sometimes people think the adjusting screws on the crescendos
are for this purpose -- they are not.

If you have a vacuum gauge you can measure the vacuum with the roll
stopped; it should be equal on both sides, around 6" or 7".  Make
sure that the cancel signal has caused the 3 intensity pneumatics to
be on before making the adjustment.

If you don't have a vacuum gauge you can do it by listening to piano
play and adjusting the spring pneumatics so the piano plays evenly
on both sides and the notes just barely play on the softest passages.
Even with a gauge the amount of vacuum at the zero intensity will vary
somewhat from one piano to the other depending on the resistance of
the piano action.

The pump should put out 20" maximum with the amplifier pneumatic fully
open and the roll stopped.  You can check this by pushing up on the
spring pneumatic- bass or treble.  This is with the modify switch at
"medium".  The same test should give you 27" or so with the switch at
"brilliant".  The 20" setting is adjusted by turning the spill spring
in or out and the brilliant by adjusting the stop screw.

You might want to "time" the crescendos before you do any of these
adjustments.  With the roll stopped go underneath the piano and pull
either 1B or 1T tube off the expression cut-out block.  Observe the
crescendo pneumatic collapsing and time it by counting seconds -- you
know, counting one one thousand, two one thousand, etc.  Now cover the
nipple so the crescendo opens.  Use the adjusting screw on the return
spring to "time" it so that it takes the same amount of time to open
and close.  I find those screws are often all the way adjusted tight.

It is also wise to set the Tempo using the Tempo test on the roll as
the tension of the motor governor spring affects the overall performance
of the piano.  First see that the roll stops when the Tempo lever is at
the extreme zero Tempo and just begins to crawl when moving it just
slightly to the right.  Adjust the control rod set screw to do this.

Now, set it at 60 and do the Tempo test.  Here is the hard part --
adjusting that nut on the grand airmotor governor!  It is way down
in the bottom and very difficult to get at, not such a problem on an
upright.  You should do this after you have adjusted the pump to put
out 20" with the amplifier open.  I often find that the nut needs to be
adjusted to weaken the spring tension.  You might have to use a screw
driver or something to turn the nuts as getting your fingers in there
is tough.

If the piano is indeed working properly the test on the roll for the
amplifier being partially closed and fully collapsed is also useful to
regulate.  This adjustment is made on the outside spring that controls
the resistance to the amplifier pneumatic.

Hope this helps,

Ben Gottfried - Ben's Player Piano Service
Richfield Springs, New York
http://www.bensplayerservice.com/