Flying Fan




Introduction: Flying Fan

Tim Anderson is the author of the "Heirloom Technology" column in Make Magazine. He is co-founde...

This fan hangs from its extension cord and flies around in circles. You can add accessories like a toilet-paper dispenser, a robotic hand for giving you high-fives, or as many cupholders as you want. To see video of this gadget in action, watch the Robot/Art movie.

Step 1: The Slipring

You can of course hang any fan from its extension cord and let it fly around. Eventually the cord will twist too much, short out, sparks will fly, and the fan will wing off into some corner of the quonset hut while the campers all shriek with delight. I think you can get a merit badge for turning in other boyscouts who do that.

This particular project uses a "Rotating Electrical Connector" a.k.a "slipring" so the fan can fly indefinitely.
Mine came from Mcmaster-Carr it is part# 7631K51 it costs $27.54 plus some extra for couple of connectors. The one I'm looking at right now has the markings "Mercotac 205 T95". It contains two little puddles of mercury with the contact wires dipped into them. When you order one it comes with a little container to ship it back to the manufacturer for disposal. I've built a couple of flying fans containing these gadgets, one of which has flown for more than a decade. Of course I now have no idea where the return mailer is, but it sure was a nice gesture.

I used to make my own sliprings which were either unreliable or too much work.
There are other cheaper sources of sliprings. Some types of electric motors have them built in. Some vcrs have them for making contact with the rotary head assembly. You can even use a "telephone line untangler" if you find one that will carry enough juice for your fan.

Step 2: Typical Installation

Here's the device that's flown at MITERS for ten or more years.
I butchered a harddrive that had a hollow shaft through one of the bearings. I installed the Mercotac slipring atop the hollow shaft just as the directions said to do.
I ran thin insulated copper wires wires through the shaft. I hoseclamped the whole unit to a pipe.

Underneath I clamped a split bar to the shaft and tied a piece of spectra string to it to suspend the fan.
I twisted the power wires around the spectra string.
The harddrive guts look too complicated. A bicycle hub with a hollow axle is just as good and looks better.

The tail of this fan is two interlocking rectangles cut from a 3-ring binder cover. The tail is attached to the fan by a couple of car antennas and some zipties. The fan is a giant muffin fan from a 19" rack. It used to cool a pdp or somesuch "mini" computer. If you have any fans like this you could give me I'd sure appreciate them.

Step 3: Speed Control

I use a Variac "Variable Voltage Output Transformer" for speed control. Mine were left to me by dead scientists, but I see that new ones are expensive. sells them and provides these nice drawings.

Some other light dimmer type thingy would probably work as well. There are rules that various dimmers don't work for resistive, inductive, or capacitive loads. You can test the limits of those rules for small motors as long as you keep them away from flammable things like houses.

To get the fan flying you'll need to throw it. That will take some practice. The fan will only fly in one direction due to coriolis/vortex voodoo reasons.



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    22 Discussions

    I made a little aeroplane that also just "flies" in a circle suspended from the roof. I recently thought about making something of this type which runs on a circuit track or rail system throughout a building, moving from room to room and able to carry small loads to be useful.

    cool and random nice maybe I should make one and add some wings if i make it ill post some pics

    used to want these things so badly every time I saw on in the toy store I said. "mom can I have that please!!!"

    Speed control for DC-powered fans of less than 15 volts:
    555-based PWM speed controller
    This is a minor modification to the common 555 timer circuit. Provides true pulse width modulation speed control with a minimum of cost and parts. Built one like it today, was pleased with it's performance.

    5 strips of toilet paper+1 foot of tape+1 ceiling fan=this thing times 5....... decent instructable though, i mean someone could have just wasted 5 bucks at the mall....

    you could keep the more rudimentary speed controls from your fan in the first place and have a 3 speed flying toilet roll dispenser also I have though of an interesting use for this using the same rail system from those movable halogen lights make a live track round the room using fairly stiff metal wire or copper piping and support it from the ceiling on rubber blocks that site below the track put 2 arms on the top of the fan and run the connector wires from the power up it to conductive wheels, use motor brushes for connecting the wheels to the power you now have a flying fan train capable of delivering cool drinks and toilet paper even use a 12volt motor and use the transformer from those lights or wire it into the ceiling and use a dimmer switch so you have speed control sorry about my uber long comment just saw a whole lotta potential for wasting time watching a fan make its way around the room

    If you don't mind about wasting power/heat, you can just put a potentiometer (which is good enough for the amount of power you're using) between the power supply and the fan to adjust speed.

    1 reply

    possible problem with the pot is that with the power running through 24/7, it'll (as you said), generate a lot of heat. The design of a pot only lets you use one end of the resistor that inside, and that end might burn itself out. I have absolutely no idea how long it'd last, but it'd work...

    but haveing a spinning tolietpaper holder would be pretty cool... oh and also, those dryers are pretty damn captivating

    This is too cool....I saw it in action once, when I first stepped into the room and met the maker. I almost didn't know how to start the conversation or divide my attention between the ceiling and the social situation. I hope I didn't seem rude, but that's what you get when you decorate with animated flying art ;-) Glad to know now how you managed the power transfer -- a mystery until today.

    2 replies

    Met the maker (Tim) or your Maker? That thing is pretty dangerous. It's really captivating though, like the dryers at a laundromat.

    Yes, just like the dryers. I wonder if that is where Tom Disch got the idea for the "fairy traps" in his excellent SF novel, "On Wings of Song"? Tim's flying fan would probably catch some fairies (which are in this case machinery-enabled disembodied mind-essences flitting about and spying where they oughtn't).