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Magnetic Track

  1. Feb 12, 2013 #1
    Hello all,

    This is my first post here, so please let me know if I'm not in the right section, as I wasn't 100% sure if this was the right place.

    I'm making a box that can change volume quickly with an actuator for a small project.
    But I need to minimize the friction in moving the wall of the box.

    Is there a way to make a magnetic track for the wall to 'slide' on? I don't mind if there are boards sticking out the back of the 'wall' to help balance it (I was going to put wheels on it originally), I just need the inside of the box to be box-like.
    I've seen small projects like this:

    What if I basically made a track for the wall like that, placed magnets on the right and left so that it wasn't touching the sides, and pushed it? Would it get stuck?


    Is there a way to maybe produce two rails that could attach to the wall that would have nearly no friction? Like below?


  2. jcsd
  3. Feb 12, 2013 #2


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    Staff: Mentor

    Hi RetroSpectrum7, http://img96.imageshack.us/img96/5725/red5e5etimes5e5e45e5e25.gif [Broken]

    Attaching magnets will increase the mass of the moving side; is that likely to upset your plans that movement be speedy? How heavy is the moveable side?
    Last edited by a moderator: May 6, 2017
  4. Feb 12, 2013 #3

    Simon Bridge

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    ... it also won't be air-tight.

    There's all sorts of stuff you can do with magnets - like you could exploit diamagnetic levitation. You pic of the railing looks interesting - just rotate the inner 45 degrees.

    There's something nagging the back of my mind about rapidly accelerating magnets inducing funny fields meaning it may be counter productive.

    The simple answer to your question:
    ... is "yes", there are lots of ways.

    But I'm with NascentOxygen - it could be counterproductive.
    I'm not sure you are addressing your design constraints - how fast do you want to move the wall? What are your energy restrictions? How big is this wall? ... and so on.
  5. Feb 12, 2013 #4
    The box should be 3 foot x 3 foot on the open side.
    I suspected that might be the case, that it might not be something I could do effectively without making things more difficult.

    Thank you guys for the response, I'm going to give this one up and go with some ball bearings, and mount the box's wall on some drawer sliders instead.
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