Thursday, March 14, 2013

Getting the Gap Correct in Electric Motor Project

It appears so many students must be building the Build Simple Electric Motor project but I have to wonder if they are running into the problems that students had in my classes. The most common problem is not scraping the insulation off the wire well enough and the next problem is the gap between the outside of the coil and the top of the magnet.

For sure the gap cannot be so small that one side of the coil hits the magnet as it turns but if the gap is too large probably an 1/8" of an inch or more the motor will not run. Ideal would probably be about 1/16".

The gap is too small between top surface of magnet and bottom edge of coil, when the coil is completely vertical it will strike the magnet.

In this motor the coil magnet gap is too large and the motor will not run. Another shim under the magnet should fix the problem.

This gap was close enough for motor to run about 1/16" inch. It looks to be larger because the picture is so large.

Bill Kuhl

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  1. Very informative post you have shared here, this is really a simple and effective post, i enjoyed it. Many thanks for sharing.

  2. Thank you so much for your comment. I have been trying to come up with a good design for a 2-pole motor but so far I am learning more what does not work.

    Bill Kuhl

  3. These days the demand of electric motor sales is being increased as well as the demand of experienced repairing experts. At the time when people are looking for a sales or repair location they should make sure to verify whether they are EASA members or not. People should make sure that the electric motor repairing experts are well trained and have experience in this field.