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Unread 20-02-2012, 09:35
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Re: Shooter burning motors...but why?

Quote:
Originally Posted by matthewdenny View Post
So... we have a shooter powered by a 550 motor. (We have destroyed both a FP and AM motor.) The motor is geared down about 7:1 using parts from a Modulox lunchbox, and then powers 2 8" dia wheels on a hex shaft. We have destroyed 2 motors after only a couple shots each, and cant figure out why. Any ideas?
It's easy to figure out why, if you gather some data:
What is the free speed (i.e. steady-state speed with no balls being launched) of your shooter wheel? If you don't know how, or don't have the equipment to measure the speed of a spinning wheel, then what is the current being drawn by the motor?

At that free speed, what %PWM are you commanding?
You've already given the 7:1 geardown ratio, and that's a good start. Just make sure that's the right number and includes everything all the way from the motor rpm to the wheel rpm.