magnetic sheilding.

Discussion in 'Physics' started by electronis whiz, Apr 11, 2014.

  1. electronis whiz

    Thread Starter Well-Known Member

    Jul 29, 2010
    I had always heard magnets will mess with computers, but what I've seen I don't agree totally. Tapes, floppy disks, etc. absolutely don't even put a magnet by them.

    Many people say put them on your case you'll mess it up due to most hard disks being mechanical. I had an old HDD I didn't care about, I decided to try it. I used a 1KW 120V AC tape eraser. It had absolutely no effect on the drive.
    I know many drives have fairly strong magnets in the actuator, so why aren't those erasing data, etc, on the drive. My only thought in both these cases is because the metal around the actuator magnets shields the force in the small area. And that the shell of an HDD is like a faraday cage, and no magnetism will go through.

    Just wondering what people thought about this, or am I just not using large enough magnetism to effect a drive. Also any theory on how a magnet near the platters on an HDD will not effect the data on that platter.
  2. #12


    Nov 30, 2010
    There you go. You have found rumors by the uneducated and found the truth by testing the ideas.
  3. electronis whiz

    Thread Starter Well-Known Member

    Jul 29, 2010
    I just remembered though, in some documentation by like NIST for data destruction says degauss the drives, maybe that would work, but it would have to be something really powerful. I don't think magnets most people have would be something to worry about with an HDD, even a magnetized screw driver, I use those on computers no problem.

    I have even seen some people in the I.T field that don't understand this stuff. I know one person that thinks even using a magnetized tool on a mother board will fry a chip. I thought really chips aren't magnetic based, so don't worry about. I'd be more concerned with ESD than a magnet.

    I volunteered at computer recycler, when I was getting into I.T. I asked one of people why aren't the actuator magnets erasing the platters he was like they aren't magnetic based. I thought what ever, I don't know how you think they work, but I'm pretty sure it's not optical, and obviously not solid state.
  4. Wendy


    Mar 24, 2008
    You pretty much have it down. Hard drives are indeed magnetic based, but they are also shielded. If I really wanted to destroy the data on a hard drive I would take a drill press to it. As it happens, I may be doing just that.