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i am trying to make a watch that looks like the speedometer from merceds benz AMG my problem is i canot figure out how to let the needle or the minute hand (call it what ever you want) rotate from 0 to 60 in an hour and then the second the needle reachs the 60 it should go back from 60 to 0 in 3 second(a negativ rotation right here) and then it should loop and the process should repeat it self.the needle position should stay the same and not change only the roation should change.the cause of the problem is the gears since the watch should be a mechanical watch and i am struggling to make the gears work toghter, i have tried many ways before and all i got was failure out of it :( there is a yt video down that makes you understannd more of what i want.

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https://www.youtube.com/watch?v=XV7ij1cICHM

ABO M7TRAF
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  • Cam mechanism with flat spiral return spring? – Vladimir Jul 12 '22 at 21:37
  • @SolarMike its the same question and its mine i did repost with more details and more explained in deapth since some people told me to do so to make it more understandable. and no it does not answer – ABO M7TRAF Jul 13 '22 at 09:46
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    Then you should have edited the original question to improve it and no post a duplicate. – Solar Mike Jul 13 '22 at 09:49
  • Don't keep creating new questions. All of these are the exact same, so improve one question. If you have a separate question, ask it as a separate question. – hazzey Jul 13 '22 at 20:25

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A half-cogged gearwheel plus a return spring will do it. ( A similar mech is used in older (electromechanical) pinball machines for all sorts of resets) You just need to include some sort of cam or detent that keeps the pawl disengaged during the "flyback" motion.

Carl Witthoft
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