Originally Posted by
sergeantseabass
Wow thats great. danirc so can you tell me how to actually get the reading of the RPMs from my motors do is it bet to just scour the interwebs unitl i find something. what is the best way that you have found to calculate scale speed. As far as the 600:1 ratio I can see that being a bit more accurate than 4:1. They really just need to change how they label the gearboxes. Even just a basic description like (3;!= higher to speed less torque, 4:1= lower top speed higher torque) or something.
To get motor RPM, I glue (with CA) a small 2-blade RC plane prop on the shaft end and measure the RPM with this tachometer:
http://www3.towerhobbies.com/cgi-bin...P?I=LXYXK9&P=8
When I measure, I also hook up a voltmeter to get the actual voltage to the motor when the RPM is measured.
The tach does not work under indoor lights (because of the AC 60 cycle flicker in the lights). Need to make the measurement outdoors or in a bright room indoors with no lights on.
Measurements are very repeatable.