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Possible to modify a magnet to be more beamlike

  1. Sep 10, 2007 #1
    Possible to modify a magnet to be more "beamlike"

    I've been wondering if it is possible to encase a magnet in something readily available that would give it more beam-like characteristics vs. field. Basically, I want to have the magnet encased so that I would get full magnetic pull on an object directly in front of the magnet but little or none when the object is not directly in front of the magnet.
  2. jcsd
  3. Sep 10, 2007 #2
    Not that I know of. Magnetic field loops need to have a path from the south to the north pole, although if the field loops were mind-numbingly huge it might seem to act like you want...
  4. Sep 10, 2007 #3
    That's actually what' I'm looking for. The loop to be large on either pole but keep very close to the magnet itself on the sides.
  5. Sep 11, 2007 #4
    Mu metal will help but there is no way to totally shield a magnetic field. Magnetics Inc. sells it but it it expensive. Try making a shield out of a ferromagnetic metal and it will likely work about as well. A preformed iron or steel box with open ends will work pretty good.
  6. Sep 12, 2007 #5
    Actually, I've been looking around and I think that for my application I'll use a rod magnet wrapped in ferromagnetic material with a mu-metal shield around that. Hopefully that will allow the field loops to pass through the ferro material while limiting the spread of the field. As soon as I get the money up to buy all the materials I need, I'll reply to this thread and let everyone know how it's working.
  7. Sep 12, 2007 #6
    Remember that the pull on an object (a magnetic dipole) by a magnetic field has nothing to do with the strength of the field as such, but with its gradient. Thus, a uniform field confined to a cylinder wouldn't actually pull anything.
  8. Sep 28, 2007 #7
    Unfortunately, really efficient "pull" requires a pancake shape coil and that will have little throw.
  9. Sep 24, 2011 #8
    Re: Possible to modify a magnet to be more "beamlike"


    These people have specially polarized magnets that attract strongly when properly aligned but repel when slightly twisted or moved off-axis. Not sure if this is exactly what you're looking for in a magnet but it's the closest commercially available product I know of that seems to match your description. Cheers.
  10. Sep 24, 2011 #9

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    Re: Possible to modify a magnet to be more "beamlike"

    This thread is 4 years old.
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