Hi gang.  I have been experimenting with the new units that Ragtime
Automated Music (RAM) sent me.  I think, with some modifications,
they will work.

First of all, replace the tracker bar (I replaced the spool frame).
The tracker bar that comes with the kit is too restrictive in the
bottom and top rows.  That, coupled with the long tubing runs,
compounds the problem of the valves not seating in the "on" position.
It simply does not have enough air flow to actuate the poppet; that
is the main reason these stacks are so leaky.

To prove my point, I tubed the Ragtime tracker bar into a Standard
player action.  The longer the tracker bar tubes, the worse this problem
became.  The results were the same on the Standard.

The valve appears to be a soft plastic of some type.  These are rather
sticky, so you need to spray them with some TFE.  The top of the valve
has a valve guide with a plastic stem speared into the top.  This stem
will distort the valve.  Pull it out and throw it away.

If at all possible, don't use the 90-degree elbows to connect the
tracker-bar tubing to the stack.  They are restrictive also.  This
stack is expected to play with long tubing runs, So it is most
important to get enough signal air to the stack.

The stack sits in the piano with long rods, and it requires much
bracing to keep it from bouncing.  I used some 1' x 4' maple boards
instead of the rods for support, and to make a frame to pull it out
of the piano like any other player stack.

This unit has standard pushrods.  I didn't think that using nails (like
RAM recommends), is quite the craftsmanship I want to be known for.

Another source for leakage is the small tubes that hold the pneumatics
together.  When they are new they hold tight, but as they age they will
loosen up.  Assemble them with PVC_e glue.  I haven't gotten it back
into the piano yet, but the stack will operate on as little as 5 inches
of suction.  For a final test, I plan to operate them from a foot pump
unit.  That should tell the tale.

NEVER run the tracker bar tubing between the rail breaks.  You will be
sorry if you do, if you ever have to service the piano.  Run the tubing
through the keybed.  Don't expect this stack to have much expression.
The diaphragm pouches will not allow that.  I will keep you posted on
how well the unit does work.

Andy Taylor