I prefer the universal mounting option
which will let the cylinder pivot. There are
times when you will need a parts movement
to be restricted to a single plane of motion,
however, so choose your mounts carefully.
Speed can be adjusted by the use of
flow controls and regulators. I run high
pressure from my compressor and then
adjust the pressure to each character with a
regulator. Each cylinder port is installed with
flow control fittings so I can further dial in
the speed at which they operate. This allows
me to have a cylinder respond at one speed when it
extends and a different speed when it retracts.
Fittings are available in either metric or standard, so it
will save you a considerable additional investment if you
standardize. Mixing sizes — even if they seem to fit — will
cause you many headaches because it could strip threads or
cause connections to leak, costing you time and money. I
don’t know about you, but both of those things are in
short supply in my shop!
The push fittings are wonderful because it makes
hooking up air lines a quick and easy process. They come in
many styles and sizes, so purchase a selection of different
ones so you are prepared to adapt your layout on the fly
Air Lines, Hoses
You can select between several different sizes, colors,
and qualities of air line. After trying numerous different
styles, I have settled on black polyurethane airline for its
kink resistance which comes in handy when having to make
tight turns on an armature. I have not been satisfied with
the look or performance of cheaper alternatives, and have
had it fail in spectacular fashion. Talk about a loud air
I use 3/8 inch line to each individual figure up to the
regulator, and then switch to 1/4 inch hose to each
Use one for every prop which will enable you to dial in
the appropriate pressure for each one. We only use enough
air pressure to get the job done. It is safer and you do not
want to waste air as it is too valuable of a resource.
These can be an extremely useful addition to your air
delivery system. I use these for inside displays or where it is
impractical to run an airline from the compressor to the
prop (Figure 4). They can be a viable solution in many
cases where you have located a prop in a remote location
that uses a small cylinder that doesn’t get activated often.
SERVO 11.2015 49
Figure 4. An 11 gallon storage tank in its hiding place.
Figure 2. Comparing a single- and a double-acting cylinder.
Figure 3. My fittings assortment will fit most needs.