Theatre Design & Technology - Summer 2019 - 53

each with independent control. To
make this operator-friendly, each solenoid was activated by a relay controlled
through a Beckhofff module, allowing
the I/O interface to be integrated with
the theatre's Hudson Motion Control
system. From there, it was possible to
write lengthy I/O cues that intermittently pulsed all 14 solenoids on a loop
at the single push of a button. To make
the physical infrastructure turntablefriendly, an I/O interface box containing
24VDC power supplies and the relays
were stored onboard the turntable. Only
EtherCAT and power for the interface
box needed to be run down into the
trap room. Wiring for the solenoids was
contained within the walls of the structure on the turntable, running through
conduit and using Ecomate connectors
for rapid hook-up between wall sections
at load-in. Extensive labeling and paper
documentation kept trouble-shooting
to a minimum. To deaden the sound of
the solenoid valves opening and closing,
which was amplified by the open, brickwalled space onstage, the solenoids
were contained in ½" MDF boxes, with
the interior lined with acoustic foam
and the exterior covered in MuteX.
The plumbing infrastructure also
had to pass through the turntable and
be load-in-friendly. A 300-gallon tank
and 3HP centrifugal pump were located in the trap room, with the pump
inside a ½" MDF box with an interior
lining of acoustic foam and the exterior
covered in Blue Jean insulation. Because the water flow at the spray-head
lines was so low, and centrifugal pumps
must constantly push water in order to
function correctly, the plumbing system
included a branch off the motor's output piping that allowed recirculation
into the tank. The main line of output
piping included a pressure gauge for
major adjustments in the system before it converted to reinforced, braided
PVC tubing as it passed up into the
turntable, allowing flexibility with the
270-degree rotation. From there, horizontal PVC piping through the turntable's base structure and vertically into
the walls carried water up to each solenoid, where it was then pulsed out to
the spray-head lines hidden inside aluminum angle trim along the tops of the
walls. At the bottom of each wall was a
recessed, sealed UHMW channel with

Wall sections were installed with open sections to allow hook-up of electrical and plumbing systems using Ecomate
connectors and PVC quick-connects.

a single drain guiding water back to the
tank in the trap room. Like the control
system's wiring, rapid hook-up between
wall sections during load-in was a priority, and PVC quick-connects worked
well. The large number of plumbing
parts and adapters to build the system
necessitated a high level of organization and part labeling to match the bill
of materials.
During the show's run, days with
two performances required the use of
fans and stage lighting to dry the fabric between shows. The sponges also
turned out to be a bit more temperamental than expected-when sponges
dry out, they shrink and never fully recover. That meant coming in on dark
days to run the effect to keep the sponges wet and, that when a piece of sponge
did shrink, the resulting gap created a
rain-like drip off the edge of the aluminum trim. Stuffing the gap with a small

Figure 4 - A
solenoid box,
bolted to a wall
frame's steel
structure, with its
lid removed.

bit of sponge eliminated the gaps and
stopped the drips. Ultimately, the effect
proved to be reliable, with the desired
organic look and no plumbing leaks
over the run of the show.

A section of wall in
progress.

SUMMER 2019

THEATRE DESIGN & TECHNOLOGY

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Theatre Design & Technology - Summer 2019

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