the angled El (Figure 10). You can then cut a small disc of
lighting gel and place it on the bulb to take intense heat
away. However, these LEDs barely get warm. Next, take
the coupling flange you drilled out earlier and snap it onto
the flange to secure the gel and bulb in place (Figure 11).
The flange itself will lock onto the PVC El, so no glue
or fasteners are needed. Besides, you might want to alter
the color of the flame at some point. We will eventually
position the Els and then glue the base to the top panel of
the enclosure, but we’ll do that later once the silk that
creates the flames is actually flying. The assembly of the
spotlights will be part of the final assembly and wiring.
Installing the Fans
The particular fans we use are very dangerous when
spinning and could probably take off a finger, so always
use extreme caution!
The fan’s casing is square and the holes we drilled are
round, so we used all-purpose silicone caulking to help
plug up around the fans and also to assist holding them
securely to the top panel. We’ll use four 1/2” lath screws
per fan to secure them, as well.
Start by drilling some very small holes into your
enclosure. Make sure each corner lines up with the holes
in the corner of the fan so you can put a screw into each
hole to secure it. You will also want to make sure that the
fans are facing the correct direction so when they spin,
the air flow will be blowing where it’s supposed to.
Usually, the label side is what you want to see when it is
mounted to the top and flipped back over to the
operating position.
Make sure to fill in any open spaces around the hole
so you don’t lose any air flow (Figure 12). Once this is
done, flip the panel over and smooth out the silicone. Set
the piece aside to dry overnight.
Hacking A PC Power
Supply, Then Connecting
Blue LEDs and Fans
We used a standard ATX computer power supply with
two 12V rails since the fans both run on 12V and use a lot
of power. We also connected the two 10 mm blue pre-wired LEDs to
one of the 12V
rails. The LEDs
use so little
power they
can share
power with no
noticeable loss
in performance
to the fan or the LED.
For this project, you will only need to use the yellow
12V wires, the one green wire, and the black ground
wires. You will also need a 10 watt/10 ohm sandbar
resistor. The red wires are 5V and not needed for this
build, so they can be cut back and shrink wrapped with
the other wires. The two yellow 12V wires will power the
blue 10 mm LED lights and the two fans.
The LEDs we used came pre-wired with a resistor, so
we just soldered the red wire from the LED to one of the
yellow wires, and the black ground wire from the LED to
the other ground wire. Don’t forget to put shrink wrap on
the wire BEFORE you solder it. Otherwise, you will have
to unsolder it to put the shrink wrap on and then resolder
it (Figure 13).
Hooking Up the Power
Supply and Splitting the
AC Power to the Switch
Let’s look at what we are powering, and what type of
power each part uses. The four LED GU10 lights are
powered by 110V and the fans and 10 mm blue LEDs get
their power from the two 12V rails.
To simplify the operation of Ruby’s Flame, we decided
to use the cord from the ATX power supply and run that
into a small electrical box we mounted inside our
enclosure. This allowed us to splice into the 110V going to
the power supply and use it to run the GU10 LED
spotlights as well, so we only have one plug to power the
whole prop.
It also allowed us to install a switch onto the side, so
as Ruby danced by she could flick the switch with her foot
or her hand to turn the entire prop on. (Basically, it’s an
off and on switch that activates all the lights and both fans
76 September 2014
FIGURE 11. Attaching the shallow
flange to the PVC light holder.
FIGURE 12. Both fans mounted to the top panel of our enclosure
with screws and clear silicone caulking.
FIGURE 13.
Wiring up the
10 mm blue
LEDs.
