F.O.P.W. Part 2 - Pneumatics
This prop, as with most I've built, has been re-engineered.
After initial testing, I discovered that the vinyl tubing I attached
was rather stiff and did not produce the effect I sought.
At left is a photo of
Latex Rubber Tubing 1/8" I.D., 1/4" O.D., 1/16" Wall.
and
Clear Vinyl Tubing .170" I.D., 1/4" O.D. 1/32" Wall.
I purchased this Latex Rubber Tubing from McMaster-Carr Supply Company.
(Part # 5234 K41) This is perfect for this prop. It is supple and resilient, and the
dimensions work well with the brass ferrule fittings already installed on the prop.
The fittings I used were purchased
at Home Depot. At left is a 1/4" n.p.t. - compression
fitting. Center and right are the tubing insert and ferrule
compression nut. These two components work
together to provide a strong leak-free connection
without crushing or otherwise distorting the tubing.
First drill a 7/16" hole through the 3/4" cap and the pipe inside.
Then use a 1/4 n.p.t. (pipe thread) tap to create threads in the p.v.c..
Pipe threads are tapered, so don't thread the tap in fully. Doing so will create
a joint that is too large. The p.v.c. is soft enough that tapping the hole isn't
really necessary, but it does make assembly easier.
Next slide the compression nut over the tubing, making sure the threads face "out"
With just a short length of tubing exposed,
push the insert into the tubing.
This is much easier if you moisten the insert first.
Thread the 1/4" n.p.t. - compression fitting into the
hole you tapped out earlier, then thread the new tubing assembly onto the compression fitting.
That's about it for the "business end" of this project.
The F.O.P.W. I built has four hoses, spaced 14" apart.
At 60 p.s.i., these really whip around nicely. (15 p.s.i. each)
but it does consume a considerable amount of air.
Above is a photo of the completed Pneumatic portion of the Whips prop.
Air enters the prop through the red hose (bottom right.)
A pressure gauge/regulator allows for precise control and
monitoring of reservoir air pressure. (which will be
approx. 60 p.s.i.)
A pneumatic reservoir holds a large amount of air.
This helps feed this props over-sized appetite.
A solenoid valve (bottom center) will open with a prop
controlling device (probably a momentary switch)
I installed a quick connect fitting on each end of the 3/4" p.v.c. main line.
I thought I would be able to connect 2 units creating a
whipping prop nine feet long.
Unfortunately, I doubt my air compressor will be able to supply
sufficient air to run this device and the other pneumatic props
I'll employ in the 2002 Haunted House.
(if you're wondering, it's a 5 h.p., 25 gallon oil-free compressor.)
Even though the new tubing's inner diameter is half the size,
this device still draws a lot of air.
One bit of advice... Make sure the solenoid valve you intend to use
will supply enough air pressure/volume.
I first used a skinner valve with 1/8" ports... Big Failure.
Now I have an ARO valve with 1/4" ports... Works Great.