In MMD 990222 I reported a problem with the PPCo's re-roll unit sup-
plied with the Full Automation Kit.  I had a number of suggestions and
here is the results for those of you who are interested.

Problem:

The vacuum from the electric pump had to be turned down so low to keep
the piano volume at a comfortable level that the re-roll unit did not
have enough power to shift the transmission into re-roll.

Testing:

1. Checked the input tubing from the tracker bar to the re-roll unit
and all was clear and unobstructed.

2. Operated the unit directly from the "Y" connector at the unit valves
and the unit shifted correctly less than half the time.

3. Removed the unit from the piano and removed the 2 unit valve blocks
from the pneumatic.  Taped off the channels leading to the pneumatic
and tried to open the pneumatic and it would not open proving the same
was air-tight and okay.

4. Tested the unit valves.  One was okay but the other leaked terribly.
Disassembled and found some black "foam" type junk had been used as the
outside (the facing seen from the top of the unit) facing.  The inside
(bottom) facing did not leak and was left alone.  Used kid skin for the
new facing and re-tested.  It passed with flying colors.

5. Re-assembled the unit and re tested.  Found that there was a "small"
leak from the cork gasket and replaced it with a leather gasket.  With
these improvements the unit was much improved.

6. Installed the unit into the piano.  Since the two valve blocks had
their own nipple, which was joined by two short pieces of gray tubing
to a "Y" connector for use with only one tracker hole, I decided to
tube each block to it's own trackerbar hole.  Now there are two inputs
rather than one.

Results:

Works very well.  Has not missed a single time since.  It's only been
a week but the owner is very confident it will give no more problems
and I feel the same.  Thanks for all the input.

Three more questions: Is someone making a _good_ pneumatic unit which
could be used in place of the PPCo's?  If not, would anyone be inter-
ested in purchasing one if someone produced a unit of high quality?  Be
honest -- Is it just as easy for you to build your own rather than buy?

Sam Harris - Greenville, North Carolina
http://www.geocities.com/Heartland/Ranch/9374