I was pleased. I can best describe the effect as a ghostly colorful vortex. It's very pretty & trippy, and meshes well with other techno effects.
This instructable describes my first prototype. While still crude, it's effective enough that I've made three duplicates so far, and plan to deploy as many as I can make at the upcoming Critical Massive festival, which is the Seattle-area Burning Man community "regional burn". I'll likely also bring a variant of this to Burning Man itself.
My camera works pretty poorly in low light, so the in-action pictures and video barely do it justice. It's most fun when viewed from below; we've spent far too much time already lying on the basement floor gazing up at the pretty swirl.
OK, on to the instructions.
Step 1: A Peek at the Goal
The blade is attached to the motor using a collet, and the motor is secured to the ceiling using a hose clamp, as shown in the second picture.
There's a thousand ways to accomplish this task, and by no means am I claiming that this is the best way. It was, however, what I could quickly accomplish using what I happened to have lying around.
Step 2: Making the Blade
First I cut one to length, about 18 inches long, using a chop saw.
Then I marked the center, and drilled a 3/8 inch diameter hole to fit the collet. Finally, I drilled a 2.5mm hole along the centerline about an inch from each of the blade ends, through which I'll pass through the EL wire.
Step 3: Set Up the EL Wire
(Full disclosure: SeattleLumin.com is my online store where I sell EL wire, drivers and accessories. Check it out!)
For this project, I used two 5 foot strands of standard EL wire, which is 2.3mm. The bright wire, which is 2.5mm is actually just a little too stiff to get the desired effect. I soldered pigtails onto the ends of the wire, connected them to a Y-connector, and connected that to a TechnoStrobe driver.
Step 4: Assembling the Components Onto the Motor
I soldered a female barrel connector to the end that matched a 9 volt wallwart I had lying around.
The collet was originally designed to hold a model plan propeller onto a gas motor, so it should have no problem holding a blade spinning so slowly in this project.
Using the collet and a few washers as spacers, I attached the blade to the motor, and tightened it all together with a 9mm wrench. Next, I threaded the EL wire through the holes and let them dangle down.
Finally, as a way to mount the whole thing to the ceiling joists, I strapped the motor to a small block of wood using a hose clamp.
The driver just dangles straight down the center. For a prototype this is fine, although in a "production" model I'd probably figure out some way to afix the driver to the blade in as balanced a fashion as possible.
Turn the driver onto strobe, turn on the power, and turn out the lights...
Step 6: Watch the Swirly!
Step 7: Future Work
1) adding multiple stands to the blade. Right now there's one strand on each end. I think that three along each half of the blade will look really good, and will also be pretty much at the limit of the driver. That means I can afix a driver to each half of the blade, each driving three five-foot strands.
2) afix the driver to the blades. Right now it's just fine to have it swirling about, but when I make things more complicated, that just won't do. I'll probably just ziptie them and call it good. One driver on each half of the blade should keep it balanced enough.
3) More blades. Again, this will really help to fill in the arc and complete the effect.