Register

If this is your first visit, please click the Sign Up now button to begin the process of creating your account so you can begin posting on our forums! The Sign Up process will only take up about a minute of two of your time.

Results 1 to 6 of 6

  1. #1

    Join Date
    Jan 2013
    Location
    berwickshire, UNITED KINGDOM
    Posts
    5
    Gallery
    My Gallery
    Models
    My Models
    Ratings
    My Feedback

    Increasing servo revolutions

    Hi everyone.

    I need to modify a hitec hs 785 sail winch servo so that it rotates 3 times the origional amount - just over 9 revolutions - thus realing 3 times as much thread.
    I've already tried larger drums on it but the increased load was too great. If i gear down the pot will that work? Not sure.Any Ideas?

    Thanks

  2. #2

    Join Date
    Jul 2007
    Location
    BlackpoolLancs, UNITED KINGDOM
    Posts
    901
    Gallery
    My Gallery
    Models
    My Models
    Ratings
    My Feedback

    RE: Increasing servo revolutions

    This would require quite major surgery to the control. 
    Does it actually need to be proportional?  If not, just lose the electronics, including the position pot, and fit an ESC to work the motor.

  3. #3

    Join Date
    Jan 2013
    Location
    berwickshire, UNITED KINGDOM
    Posts
    5
    Gallery
    My Gallery
    Models
    My Models
    Ratings
    My Feedback

    RE: Increasing servo revolutions

    yeah unfortunatly it does. so major surgery?

  4. #4

    Join Date
    Jul 2007
    Location
    BlackpoolLancs, UNITED KINGDOM
    Posts
    901
    Gallery
    My Gallery
    Models
    My Models
    Ratings
    My Feedback

    RE: Increasing servo revolutions

    It MIGHT be possible to insert a resistor in each of the outer legs of the sensing pot.  This depends on how long the legs are and how much room there is.  Doing that should increase the travel required to give the comparator the range of voltages it expects, but nothing is guaranteed.  Some experimentation with different values would be needed, but a good starting point would be about half the value of the pot, typically about 5K. Resistors are cheap enough at your local Maplins.  Too high a value could cause it to try to drive past the end of the track, bad news all round.
    Normally the pot travels over the middle 1/3 of its track.  Full travel is 270 degrees, a servo arm covers about 90.  Translating this to a 10 turn pot gives 3 and a bit turns.
    I have been using non-prop winches for ages, using the idea that I only tell the thing to drive one way or the other until I think its got where I want it, then I let go of the stick.  I've also got boats with propo winches, and they are more fiddly to use - you can't let go of a spring loaded stick without the winch repositions itself.

  5. #5

    Join Date
    Jan 2013
    Location
    berwickshire, UNITED KINGDOM
    Posts
    5
    Gallery
    My Gallery
    Models
    My Models
    Ratings
    My Feedback

    RE: Increasing servo revolutions

    ok cool, thanks very much. I'm not hugely experienced with servo's, but i'll look into it and let you know how i get on

  6. #6

    Join Date
    Jul 2007
    Location
    BlackpoolLancs, UNITED KINGDOM
    Posts
    901
    Gallery
    My Gallery
    Models
    My Models
    Ratings
    My Feedback

    RE: Increasing servo revolutions

    Oddly enough, just found this - http://www.rcgroups.com/forums/showthread.php?t=1428266
    It sounds like your setup, the guy who did it used 2K2 resistors.


Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
  •  
All times are GMT -6. The time now is 02:01 PM.

SEO by vBSEO 3.6.1 ©2011, Crawlability, Inc.