want to create a solar powered rotating display for class

You've got several problems. How much current does the motor need to start/run? Measure it. Toy motors are probably not designed to run on low current. You have no idea what solar cells you're getting. Solar cells are rated for a LOT of light. Unless you're running it outside in direct sunlight, you won't get nearly the current you expect.

Go buy a packaged solar panel. You can get one designed to keep your car battery charged for about $20 at a auto parts store or harbor freight online. It'll be rugged and save you much hassle. And it'll have a specification, so you can determine if it will run your motor before you buy it. And you get tired of watching your gizmo run, you'll still have a solar panel that can keep your RV battery charged.

"Slowly" is another problem. Most motors turn fast. You'll need some sort of gearing.

On 2/6/2010 12:02 PM daviddschool spake thus:

As others pointed out, there are 2 problems you need to solve:

1. Supplying enough current to the motor.
2. Getting a gearmotor, since a raw naked motor will spin *waaay* too fast, and probably won't have enough torque to spin your display. (Gearing the motor down decreases the speed and increases the torque.)

Regarding the first problem, I disagree with the reply that told you, basically, it won't work with junk/surplus solar cells. If they're cheap enough, I'd go ahead and try them. Those little motors don't take much current. And if you have a bunch of similar cells, you can always wire them up in series and parallel to increase the voltage or current.

Here are some places where you can find small DC gearmotors (some of them probably have solar cells too):

Good luck, and have fun with the project.

On 2/6/2010 3:42 PM David Nebenzahl spake thus:

Here's one small DC gearmotor that would probably work:

It runs on as little as 3 volts (perhaps even less) and spins at 22 rpm at that voltage, so they say. Plus it's cheap ($3.50). The problem with this guy is connecting your CD to the output gear, since there's no shaft; you could probably glue something to the gear to connect it. (You'll have similar challenges with any motor you get, since it will probably not have a nice CD-hole-sized output shaft.)

On Sat, 6 Feb 2010 12:02:00 -0800 (PST), daviddschool put finger to keyboard and composed:

Why not just gut an old CD/DVD player?

Remove the CD/DVD loader mechanism, and wire up the tray and spin motors to a solar panel array via a bank of switches. You could use the existing wire harnesses.

- Franc Zabkar

re_Code=3DH...

How slowly? If 1 rpm will do, get a cheap clock and connect the CD to the second hand. If you need it a bit faster, mount the CD on a ball race and drive it from the rim with a little bit of rubber tubing on the motor shaft.

Google will find motors designed to be solar-powered.

Chris

How are you going to connect the broken pieces? Most of the surplus like this I've seen had no solder terminals. only a few of the larger pieces still had terminals. They want $10 for surplus. You can buy a new

I trust the point of this display is to show how little power solar cells produce.

Sylvia.