Weird texture on RMBP unibody?

Discussion in 'MacBook Pro' started by Jamesesesesess, Jul 22, 2012.

  1. Jamesesesesess macrumors 6502a

    Joined:
    Nov 26, 2011
    #1
    Has anyone else experienced this? Sometimes if I just run my finger/hand across the unibody, there's this weird pulsating feeling as if it has an electric current running through it. I never feel it if I just touch the unibody, only if I run my finger/hand across it. I first noticed it one time when I closed the lid on my RMBP but now I've been just running my finger across the palm rest area because it's so strange. Could it just be the texture on the casing causing a light skid with my skin, or some kind of defect with the coating? It's not a big deal to me, it's just interesting and strange. Anyone else experiencing this?
     
  2. Kafka macrumors 6502

    Joined:
    Mar 10, 2011
    #2
    Try it again when the laptop is on battery. I think it's the same with most current Apple laptops?
     
  3. mac1984user macrumors 6502a

    mac1984user

    Joined:
    Dec 10, 2009
    Location:
    United Kingdom
    #3
    Totally normal. I noticed it the first time I came to the UK with my PowerBook ages ago. At 110v, you don't feel anything, but at 240v, it's quite common to have that pulsating sensation. One time my wife touched my bare shoulder and sensed the pulse through my skin! She even looked away and correctly stated when I was touching the computer and when I wasn't. I've been dealing with this for years with every metal Mac. Nothing to worry about!
     
  4. iwaffles macrumors newbie

    Joined:
    Mar 25, 2006
    Location:
    Mountain View, CA
    #4
    I had a similar feeling with my last MBP. I thought I was either a. crazy or b. it had some sort of short. It only happened when I moved my finger across the casing, though.

    Maybe it's some sort of static electricity? Maybe it's time for a tinfoil hat?
     
  5. jav6454 macrumors P6

    jav6454

    Joined:
    Nov 14, 2007
    Location:
    1 Geostationary Tower Plaza
    #5
    Then it is static energy that is not getting correctly discharged.
     
  6. Jamesesesesess thread starter macrumors 6502a

    Joined:
    Nov 26, 2011
    #6
    Wow glad I'm not alone! It must be happening because the charger is plugged in then. It's plugged in about 90% of the time.
     
  7. eron macrumors 6502

    Joined:
    Dec 2, 2008
    #7
    Because your power at your location current isn't 'clean', and needs to be grounded. Use the extension cord that came with your macbook. The short power head doesn't ground the connection.
     
  8. parish macrumors 65816

    parish

    Joined:
    Apr 14, 2009
    Location:
    Wilts., UK
    #8
    Neither does the extension lead - they both plug into the 2-pin connector on the PSU. Or maybe I'm misunderstanding what you're saying?
     
  9. GekkePrutser macrumors 6502a

    GekkePrutser

    Joined:
    Aug 18, 2005
    Location:
    Ireland
    #9
    The extension cord has a grounding pin (which works through the metal disc that the connector slides in to). That's the third pin.

    The duckhead doesn't have a grounding pin, nor does it have the little metal contacts that connect to the disc but the extension lead does (at least the UK and EU 'Schuko' ones do).

    By the way this feeling is indeed normal, I've had it ever since my Alu PowerBook which I got in 2004 (and the power adaptor design actually stems from that era, I think it's the only Apple design they didn't change all that time :) ). You can feel it because the case is metal and thus conductive, that's why most PC laptops don't exhibit this. I usually use the extension lead too because it is a bit uncomfortable.
     
  10. parish macrumors 65816

    parish

    Joined:
    Apr 14, 2009
    Location:
    Wilts., UK
    #10
    Ah, I'd never spotted that. Curious that the 'duckhead' doesn't though :confused:
     
  11. GekkePrutser, Jul 23, 2012
    Last edited: Jul 23, 2012

    GekkePrutser macrumors 6502a

    GekkePrutser

    Joined:
    Aug 18, 2005
    Location:
    Ireland
    #11
    Yeah I think they're called duckhead because the U.S. one actually looks a bit like the head of a duck, with the pins folded out :)

    [​IMG]

    I think that's also the reason it doesn't have grounding: The US model is made to be as slim as possible and has a folding-pin design. That wouldn't fit if the ground pin was also included.

    The UK plug is way too bulky for this to work in such a small design, and in the UK the ground pin must always be present to open the socket latch, even if it is only plastic. I've even seen them with metal but not actually grounded. But I think the U.S. model design was probably the one that started the ungrounded duckheads thing :)

    You can also use a short cable with a 'figure-eight' (or rather IEC 320 C7 plug). Maplin have a nice cable with a folding pin plug which I use in my laptop case - I'm always afraid the large pins will press on the MacBook and cause a dent. But this will also not be grounded as the metal disc grounding thing is a proprietary Apple design.
     
  12. ixodes macrumors 601

    ixodes

    Joined:
    Jan 11, 2012
    Location:
    Pacific Coast, USA
    #12
    Apple sets most people's expectations too high with all the hype. I'm sure yours is just fine. If you're really concerned you have a warranty.
     

Share This Page