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Help balancing an unequal lever thru an arc - (Foldover flagpole)

  1. Jun 5, 2012 #1
    I am constructing a pipe flagpole that instead of using a rope or wire to run the flag up, has a pivotrod or axel near the bottom (fulcrum point) that allows the entire pole to be pulled down when unlocked. The Idea is that you attach a piece of chain a ways up the pole and use it to pull the pole over to change the flag. My problem is the balancing -- I have used these on airports before - light poles that lay over so you can change the lightbulbs etc.. but I don't know how to calculate the weight needed (even in a rough guess) to allow the laying over to be controllable..

    The pole has 27 feet above the fulcrum point - and 5.5 below the fulcrum point.. I went out to the tip of the long arm I weighed 68 lb of down force with a scale.. My concern and lack of experience falls in the area of the arc - as the pole will actually require less weight as it goes up.. I want it to remain upright (in normal flagpole position) when initially unlocked/released and yet be able to pull it over so I can change the flag.. This arrangement isn't that uncommon -- I just don't know how to determine the proper amount of weight for the base... I don't know what is important info and what isn't.. I may not have provided enough details - but would sure appreciate if someone could point me in the correct direction..
    My initial thought would be a counterweight just slightly more than the 68 lbs of downforce (weight) measured at the end (top) of the flagpole when it is layed over -- but is that correct ? I'm going in circles here... THANK YOU for any assistance..
     
  2. jcsd
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