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I know it's not very realistic to have a wind farm in early Tombstone, but I had to give it a try.  I found some cheap hand cooling fans (they type you see people carrying around in the summer).  Only one dollar each at the Dollar Store, so I picked up a bunch of them just for the motors.  Took them apart and hooked them up to a small transformer to run in unison.  Also built a shell type building to hold them.  Here's the fans I used.

These are nice little devices and the motors are great for small projects, if you are interested.  After hooking them up with a toggle on my fun board I was able to get them up and running.  Here's a short video showing the final project in action.

Hope you enjoyed looking at my little experiment.

Tombstone Southwest Railroad O Gauge

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Not to be a wet blanket, but it's unlikely you can maintain a realistic, say, 10 RPM by simply adjusting the voltage.  It has to do with the speed-torque capability of such DC can motors.  Additionally, if you could find a sweet-spot voltage that maintains a slow RPM, that when you first apply that voltage it would not be enough to start the rotation.

By all means give it a whirl (after all we're talking $1!), but if you're determined consider a DC gearmotor which would be in the, say, $5 range.  A gearmotor or gearbox in the 100:1 range would be a good starting point; this lets the motor itself run at, say, 1000 RPM where it will better hold a constant speed.  Depending on your specific windmill, you might find the biggest challenge is fabricating a coupler/mating between motor and blade shaft so that you don't have wobble (aka shaft runout).

If you post some closeup photos showing what you're trying to spin and how much space you have I'll make additional comments.

Lots of good ideas here.  I'm working on a large turbine using the same motor. Using pic pipe that the fan casing slips into and a wooden base to make it stand up.  I'm thinking I can make the blades from heavier shoped wood so that it slows the motor down. I don't plan on running it that much that it will damage the motor.  I like the idea for using the fan to move foliage or maybe even getting some flames to wave.  I also like the idea that they are already encased in a frame work that is very versatile.

I agree with Stan, I think it will be challenging to get a standard motor to turn that slowly and reliably.

If it were my project, I think I would make the turbine mast hollow and run a string belt through it to an erector set motor or an old rotisserie motor located underneath the layout. That would be much easier than trying to locate special motors and gears and coupling at the top of the turbine. All you would need at the top is a shaft with a pulley. Would not be easy to move, though. 

mike g. posted:

You could always try this motor at 2 RPM.

http://www.sciplus.com/p/230VA...ING-MOTOR-2-RPM_5316

I wouldn't try that as it requires 230V AC to operate.   Also, 30 seconds per revolution might be a bit slow but to each his own.

BrianEso posted:

I have been fooling with different types of motors found in several old toys.

I have a few with tiny shafts on them so i was thinking of using thick rubbet bands to slow the rpm down.

If you've found a DC motor that delivers sufficient torque while maintaining slow-speed operation then I can see how a rubber-band pulley transmission can work.  But I'd think that DC motor assembly would have an integral gearbox (which many toy mechanisms have).
 
If you'd rather buy-than-build, here's an example of what I mean by a DC gearmotor.  eBay is not for everyone but with the robotics craze you can buy similar gearmotors from several U.S. suppliers for a bit more.
 
dc gearmotor
You'll need a source of adjustable DC voltage to set the desired RPM and it will require soldering to hook up the motor terminals.  It says 6V 30RPM but you can run it at 5V, 4V, etc.. to slow it down and maintain speed since the motor itself is running at 1000 RPM or more which is where it "wants" to operate.  Depending on whether you're starting from 14-16V AC accessory voltage or already have DC wall-wart power adapter for another accessory, you can use an adjustable voltage regulator module ($1-3 on eBay, free shipping) to drive the DC gearmotor.  Even with your rubber-band method, while you can adjust speed by messing with pulley diameters, it might be easier to use an adjustable voltage regulator module to fine-tune speed once you've assembled a working mechanical transmission.
 

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gunrunnerjohn posted:

I have one of those Stan, even at low voltages, it has gobs of torque at the output shaft.  It runs at 10 RPM at 1.5 volts, the lowest my supply wanted to go.

Good info!  

Note the front plate has 2 conveniently positioned threaded screw mounting holes though they're undoubtedly metric.  Many times motor assemblies re-purposed from an old toy will have inconvenient or lack in a practical mounting method.  Again, I think the mounting/coupling is the issue.  Providing a suitable voltage will be the easy part.

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