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Unread 18-01-2008, 20:59
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Re: Movement of the Fisher Price motors

Quote:
Originally Posted by sanddrag View Post
You can put the Victor(s) on "brake" mode which will help a little bit. It might still fall but not as fast. Traditionally worm gear setups don't fall (backdrive). The Van Door motor is the exception.
Whether or not a worm gear backdrives is dependent on the angle of the worm. If the angle is less than 5 degrees it probably won't backdrive. More than that and it probably will. This is an approximate number and how your system responds depends on many things including how smoothly your gears turn and how the load is applied.

If I recall correctly, the worm on the vandoor is around 10 degrees. I haven't looked closely at this year's motor, but older versions had an adjusting screw that could be used to increase the drag on the system and reduce a tendency to backdrive. I wouldn't reccommend making it too tight though!
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