Messed up Solder Job

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  • Cmpfreak88
    New Member
    • Jul 2012
    • 4
    • USA

    #1

    Messed up Solder Job

    Hey all. So I bought a Hanns-G HG281D monitor from a guy a couple months ago, it was broken, he replaced a couple caps, then sold it to me. Well, after a couple months it started giving me problems so I found these forums and when it finally gave out I recapped the logic board... well... tried. Turns out he used more junk caps that failed and not only that, when he replaced them he messed up the board so trying to work around what he did was a pain... Plus I don't solder regularly so my first couple solders weren't that great... I replaced the ones I figured were the problem, started the monitor up and it worked! But as recommended by the forums I continued to replace the caps since they were CapXon caps. I've attached some pictures of what I'm about to explain...

    So I got to the last cap and for the life of me could not get the hole cleaned up. Solder sucker didn't work, wick didn't work, and because this was the last one I was just getting frustrated. Anyways... I ended up messing it up, tried to drill it out, and now I'm assuming the board is pretty much dead and I'm resigned to the fact that I'll probably have to buy a new one. Anyways, I'm not sure how these work exactly. I started to just try and scrape off the top layer to uncover the traces and just solder onto those but I don't know if there's other layers this piece needs to get to or which traces I should even connect to... Any help or advice would be appreciated if there's any way I can salvage this!
    Attached Files
  • selldoor
    Slow Learner
    • Dec 2010
    • 7870

    #2
    Re: Messed up Solder Job

    Ok - should be fixable, but I am an optimist!

    Please provise a close up picture of the area - both sides.

    Also try and do the same again using a very bright light
    behind the board to try and silhouette the traces (may not work- depends on the board)

    Power off, put your meter on ohms 2000 and put the black probe on the earthring (red circle) then probe each cap solder point with the red probe (red & pink dots)
    Post results.
    The Meter still on ohms test from possible "through" in yellow box to negative cap soler point (yellow dots).
    You may need to push a very thin wire through the "through"
    Post result
    Attached Files
    Please upload pictures using attachment function when ask for help on the repair
    http://www.badcaps.net/forum/showthread.php?t=39740

    Comment

    • Cmpfreak88
      New Member
      • Jul 2012
      • 4
      • USA

      #3
      Re: Messed up Solder Job

      Alright, attached are the close-ups.

      From the earthring to:
      Positive - Mostly open, if I wiggle it I can sometimes find a spot or two where it will show continuity (short)
      Ground - Shows full continuity (short)

      The second test showed open, but from the pictures showing the traces it looks like it goes up near where I scraped off the trace. Checking from the through to the exposed trace shows continuity.

      So it looks like it's just a problem with that positive terminal. Checking from the earthring to the positive trace I exposed showed open. Should I try to expose more of this or would is be best to try and clean out the through and see if I can get a better contact point?
      Attached Files

      Comment

      • selldoor
        Slow Learner
        • Dec 2010
        • 7870

        #4
        Re: Messed up Solder Job

        Ok - damn good pictures- If you think the negative side of the cap will be good - seems ok from have you have tested, then there are a couple of suggestions for the positive side.

        1) If there is enough trace scraped away for you to get a thin layer of solder on it then do that first. If you need to scrape a little further down the trace but you are then getting very close to the trace on the right.
        Next get some very thin wire - thin enough to go down the hole where the positive leg of the cap will go and also thin enough to get the leg in as well.Put the wire in the hole and solder to the tinned trace. Fit the cap as normal, try and get the solder to flow onto the wire without unsoldering it from the trace.
        2) It looks like the trace goes to one of the pins on the
        8 legged IC. If you can see which or can find out which by identiying the IC and getting a datasheet for it then you just need get a small piece of insulated wire, solder one end to the pin on the chip and having made a loop on the other end, solder the loop onto the positive leg of the cap.
        Please upload pictures using attachment function when ask for help on the repair
        http://www.badcaps.net/forum/showthread.php?t=39740

        Comment

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