Where can I find a good motor?

[John motz]

I have messed up on the lenz turbine I was working on and decided to do the chispito design instead. It seemed easier. I have everything except the motor and the hub. The blades are from a 6 inch pvc pipe. This is experimental and want to know what type of motor would be best for this design. I keep reading that treadmill motors work well. Any help would be appreciated.

Thanks.

JohhnyM

[John motz]

Just to clarify the pvc pipe is 6 inches in diameter and 24 by length.

[Rob Beckers]

John, depends a bit on the threadmill, my understanding is that many of them use permanent magnet motors. Those things work both ways, you can run them as a generator too, out comes "wild AC". The "wild" part means the frequency and Voltage aren't constant, they vary with RPM.

Old servo motors work too. Those are permanent magnet motors as well. There's various car alternator conversions available, though they tend to (still) be high-RPM before anything meaningful comes out.

The first step is to narrow down parameters a bit: What RPM and power output are you trying to shoot for? You'll need something that produces reasonable Voltages and currents for that range.

-RoB-

[John motz]

I am looking for something between 20-30 rpms per volt.

"The motor is the core of Chispito. Without it, forget about the rest. You are looking for a permanent magnet motor. Why permanent magnets? Because they work well as generators, which is what we want here. Also, they don’t normally require high rpms to get some usable power out of them. To find out if your motor might work, look on the label and find the rpms. Then, find the working voltage. Divide rpms by voltage to get rpms per volt. For this sort of machine, you are looking for 25-35 rpms per volt. The more rpms per volt, the faster Chispito needs to turn to charge a battery, which means you will need more wind before it will start charging. So, go for low rpms per volt.

The motor should also have a hub attached. If it doesn’t, you’ll have to find something that works. Saw blades, pulleys, and hubs from something else might work, but remember, this thing can get up to 1500 rpms, so get that hub on there tight!

The motor should be easy to turn by hand, and it should produce a bit of voltage with a hand turn. Something in the range of 1-2 volts with a hand turn will be great. If in doubt, hook the motor to a lathe or drill press to get a good representation of what it will output at set speeds. If the machine can’t get power out of it, neither will the wind."

That is from the site. http://velacreations.com/articles/energy/chispito-information/

I also thought of making a hub if I can't find a motor with one attached.