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Old Oct 12, 2012, 06:34 PM
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Quote:
Originally Posted by erdnuckel2 View Post
...

Oh, and do I have to use (or WOULD I have to use) a clockwise or counter-clockwise motor?

Thanks for any help
E2
I posted an answer to this question a while back ago in a different thread:

Quote:
Originally Posted by i812 View Post
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I believe the Mini's Tail Motor has internal wire Brushes which are bent and assembled at an angle in such a way that they work best only when the Motor is spinning in a particular direction. Although swapping wires to reverse the polarity of the Voltage going into the Motor will make the Motor spin backwards, I think spinning the Motor backwards will cause the wire brushes wear out faster. Perhaps this crude diagram may help explain why:

/O/

Both wire Brushes (both "/") are bent and angled so their tips apply pressure and have electrical contact with the Commutator (the "O"). In the above diagram, if the Commutator is rotated CW, the springiness of the wire Brushes allow them to automatically maintain slight electrical contact pressure as they "slide" along the Commutator; however, if the Commutator is rotated CCW, the Commutator will "push" on the wire Brushes causing them to become hotter, wear faster, and fail prematurely.

As an example, think how a cat or dog's hair behaves depending on which way it is brushed: in one direction stroking downward from the top of their head towards the legs, the hair lays flat, and the stroke is smooth; whereas, in the opposite direction stroking upward from the legs towards the top of the head, the hair wants to stand up and the stroke is rough. With all the wire brushed Motors I've seen, the wire brushes behave the same way, and have a preferred direction of being "stroked" (i.e. rotating around) the Commutator.

Although the below EatAtJoes video is of a different Tail Motor, starting at 1:35 it shows what wire Brushes look like, how they are angled and bent to make spring contact with the Commutator:
E Flite Blade MSR Tail Motor End Cap Repair (9 min 6 sec)

Quote:
Originally Posted by i812 View Post
I think if a different Motor designed to spin in the opposite direction was used, or a Tail Rotor that has oppositely angled pitch, then it might be a better mod, because it would probably last longer.
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