Phil Dayson mentioned the mounting of Pianomation solenoids on
his harpsichord.  I have worked with electronic players since 1978
and there are two items of which you may not be aware.

(1) The metal rail that the solenoids mount on in Pianocorder,
PianoDisc and Pianomation players serves two valuable purpose.  Both
are important enough that you may wish to replace your wood rail with
metal.  First, the rail becomes a heat sink that pulls off heat from
the magnet as it works for long periods and begins to heat up.  (Also
your sticky tape will probably melt and fall off when they heat up
enough.)

(2) Also we were told that to make the Pianocorder able to play louder,
as in a concert grand, we should install dense ferrous (iron) metal
into the cutouts behind the aluminum rail in order to give the magnets
more oomph.  The fact that all other solenoid players since Pianocorder
use heavy iron rails leads me to believe that this was fact.  The use
of the iron rails for your harpsichord solenoids will remove heat and
make their pull stronger, thereby needing less power.

My suggestion is that you change the rail over to iron at your earliest
convenience.

D. L. Bullock    the Piano World    St. Louis