Science Buddies: "Ask an Expert"

Hey I'm trying to do the simple electric motor for my science fair project this year and my motor won't spin. It used to spin really well but now it wont. I've tried making a new coil, testing the battery, and changed the magnets and it still won't spin. Any help would be appreciated. Thanks Micale

Micale18 - This is a pretty easy and interesting project. One of the biggest problems is carefully scraping insulation from only half of the circumference of the coil wire that is acting as the motor shaft. This becomes the switching commutator to energize the coil at the precise moments as it passes through the field created by the magnet. You said that your motor used to spin but now it doesn't operate. It might be that as you continued to operate the motor, the varnish insulation on the wire that created the commutation action simply was burned through, now you don't have a switching capability. You should also experiment with the position of the magnet to achieve optimum operating capability. Check out your armature with a magnifying glass and possibly an ohmmeter to check for an insulation breakdown.

Here is a short YouTube I did a few years ago demonstrating the motor.

https://www.youtube.com/watch?v=5T5Nfi6N96Q

Rick Marz