Small motor timing
 

I've been diving (headfirst) into the concepts behind how our little motors run. One of the questions on my mind has been about timing the motor. At this point I understand that timing (for brushed) boils down to relocating the brushes around the commutator in relation to the north and south poles of the magnets until the lowest current draw at a determined load is reached.

That said, why are we unable to set the timing on the smaller motors such as speed 300s and below? My guess is that the smaller field strength makes any timing adjustment negligable at best, but I'm uncertain.

A second question that I have is why use just two curved magnets? Would we get a better running motor by using multiple smaller bar magnets around the can? Would this eliminate the need for timing?

Thoughts?

Chris.

RE: Small motor timing
 

Actually, you can set the timing on most of the smaller motors. It's quite common to retime the Speed 300 motor in a GWS EPS300C drive, because the motor comes timed from the factory to run forward, but it runs in reverse in the gear drive.

The problem is, it's just not convenient to do. It's a hack. These motors are not meant to be used in model airplanes; they're mass produced for other reasons. One common use for a Speed 400 motor is for the fan motor in electric hair dryers! Speed 600 motors make their way into electric drills! You could call our use of mass-produced can motors in R/C planes a hack, too. The applications these motors are designed for do not require absolute peak performance, so they're set for a mild timing and fixed there.

To retime the motor is exactly the same as retiming an adjustable motor. You rotate the rear endbell in relation to the field magnets. With cheap can motors, you have to bend up the tabs and then figure out how to secure the endbell after retiming.