fun with pager motors

My dad's pager recently went berzerk, so I, naturally, wanted to gut it and take the tiny motor inside it. These things, known in the amateur robotists as, well, "pager motors", are extremely small, low power, low voltage, but a suprising amount of torque all things considered. A pager motor, when inside the pager, has a small half-cylindrical weight on it. This way, when the shaft spins at high speeds the weight falls from one side to the other, which is the 'vibrating' you feel when you get a page. However, the first you need to do to be able to use the motor in any useful way is remove the weight. This is fairly easy, and should take no more than five or ten minutes.

Okay, the first thing you need to do is fetch a small nail, a vice of some sort, a pair of needle-nosed pliers, and a hammer. First, place the weight into the clamp, but be careful not to clamp the motor itself. See the picture if you don't get it.
Now place the nail in the pliers so you are grabbing it by the tip of the pliers, and hold it right on top of the weight. Place it so the nail is resting on top of the shaft of the motor, not on the weight itself. Make sure the clamp is tightened, and lightly tap the top of the nail, just the nail. With any luck the motor will pop free, and the small weight will be left still in the clamp. Make sure you are doing this over a table, or have a cloth under the clamp so the pager motor doesn't drop to the floor.

Seeing as how the pager this motor came in ran off of one single AAA battery, it runs on 1.5 volts, and after testing it, no load current was approximately 55 milliamps, and stalled current was a little over 100 milliamps. I have not measured the torque yet, but this little motor packs a punch! If you want to purchase one online, check out www.pagermotors.com. They have some (what I have heard) quality motors, and extremely cheap, as in ~3 bucks or less, even down to a buck fifty. Another place you might check if you are interested in small robots, or solar powered robots is solarbotics.
A picture of the motor (weight removed) on my pinky finger

The motor, with weight removed, alongside and American cent

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