Expert: Daniel Mazur - 7/15/2006

Question
Hi,

haha, i'm a college student, exploring various objects at the time but i guess i should have phrased my question in that how i would transport a powerful neodymium magnet. Like if i were to carry one to show a friend or something, i wouldnt want to destroy every electronic equipment that i come across. So i was wondering how to make the magnet safe for carrying in a backpack and maybe keep it in a locked container.


Thanks




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Followup To

Question -
Hi,

I was wondering how one would store neodymium magnets. Would you need a magnet shield or something like that?


Thanks

Answer -
Hi,

I a not sure which property of Nd magnets concerns you. If it is just a worry that if it ever catches on a steel surface, you'll never pull it off, it's no problem. Some magnets we keep hanging on metal shelves, making sure that it's their side, not a pole, that's in contact with the metal. Others we keep in small plastic boxes, wall thickness 1 mm. You know that magnetic field drops fast with distance, so even 1 mm makes sure that you can pick the boxes up without a problem.

If you are concerned about the magnets influencing things around, you just have to keep them away, far enough. It helps matters, if you have a soft-magnetic steel U-piece, where you can store the magnet between the ends of it, because steel concentrates the magnetic field lines inside it and leaves just some fraction to stray. Just remember to put some plastic spacers between the Nd magnet and the "horseshoe", so you needn't to wrestle with it later.

I hope this helps.
Daniel

Answer
Aye,

I get it now. Well, the second paragraph of my first response applies here. You'd do best to have a steel case for it, so that the magnetic induction lines are concentrated in the walls and the stray field is thus reduced. Apart from that, whatever luggage you transport it in, you'd get most efficient results with a cubic box (and I mean a CUBE), while you pack the magnet so that it stays in the center of it during transport. Size of the box depends on how large and strong magnet you have and how much you want the stray field reduced.

I don't think you'll have a problem with commercially available magnets anyway, they are far from strong enough to do any harm. That is, any magnet can destroy magnetic records (tapes, hard and floppy discs), but static field generally won't harm electronics. You'd need a strong electromagnetic pulse to do that, but that can only happen, if you shoot your magnet past (very close) an el. device from a rifle! Even heart pacemakers, which are susceptible to strong mag. fields, will do fine, unless you place the magnet DIRECTLY on the sick persons chest, over the implant.

Well, unless I know, how strong magnet we are talking about, I don't think I can help more.

Use it well!
Daniel