I assembled and cut the cardboard and took the pictures at home, but the rest of this was Made at Techshop Check out to see if there is one in your area.
What you will need:
$12 | 1 x RC Reversible DC Motor Speed Controller 12-40V 0-3A 60W (ebay)
$10 | 1 x 12V 60 RPM 60RPM High Torque Gear Box Electric Motor (ebay) Or buy in USA for $15
$2 | 10ft 3/4 PVC Pipe (We only need about 5 feet, but it comes in 10 foot lengths at home depot)
$.50 | 4 x 3/4" PVC Pipe Tee Adapters
$0 | Enough Cardboard for the size of the fan, in my case it was less than 2'x2'
$0 | Duck Tape
$0 | Stapler
$0 | 12V Drill Battery or 9V battery and 9V leads
$1 | Small Gauge Cooper Wire
$0 | A Light of Some Kind
Optional, Fog Machine or Frost Shower Curtain. Or 12V Drill Battery or 12V Battery Equivalent.
Total Base Cost = ~$30 I had the Motor, Speed Controller, and drill battery Laying around my house. At 9V battery will work temporarily for testing. I know that with the Motor controller a 9V battery will rotate for 6 hours. (Motor accepts variable Voltage from potentiometer).
For my final design I created a four blade fan and projected onto the back of a frosh shower curtain, the screen lowered the light pointed into the crowds eyes. Sometimes in a dark venue it is not a good idea to blast people in the eyes with light.
I apologize for some of the images I don't have a macro camera, so shots can get tough.
Step 1: The Setup
Light and Shadow manipulation can be an art form, just remember. The further away from the light source, the fuzzier the shadow will become. If you want a huge fan with clarity, then you'll have to cut out a huge piece of cardboard.
As for build quality, cardboard is not the best, but it serves it's purpose and is easily replaceable. Also, the shadow design is based on your cardboard cut out prefferences, as you will see in this tutorial I tested two different types of Cardboard cutouts.
Step 2: Cutting and Creating
So grab some cardboard and start making. three blade fans, four blade, heck you can cut out pac-man's if you want.
In the images below I simply tried to find a good center point / balancing point for the center of the fan. Then stapled the pieces together and added duck tape if necessary for extra support.
When done, find the center balancing point again and punch a hole in the cardboard to mark it.
Step 3: Preping the PVC
The DC motor will fit perfectly into the 3/4" PVC T Adapter.
Simply Cut the PVC pipe into 5 Pieces, longest for the neck that supports the fan and shorter for the legs that keep everything in position.
Connect all the pieces and slap on your cardboard to make sure that nothing is touching the shaft or the floor.
Step 4: Connecting the Electronics
Pretty Simple: Connect the Positive (Red) to the + on the board and Battery, and the Negative (Black) connects to the - IF done right an LED light should come on.
Next you can plug in the motor and flip the switch. Turn the potentiometer (knob) to adjust the speed. The motor should start turning and the cardboard with it. This motor is designed to go fast enough for the look you want and slower than any standard fan will run. The results are pretty cool and if you experiment with the fan shape and distance from the light you might be surprised at what you can achieve
Try wrapping the cables around the base of the fan and set it up where ever you want.
Hope this helps you on your next film project or stage show.
And visit techshop for all the tools you will need for any type of project. www.techshop.ws