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Thread: Remove Solder from fragile part

  1. #1
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    Default Remove Solder from fragile part

    Looking for recommendations on removing little bits of solder from some SOJ-40 memory chips so I can install them in a couple video cards.

    What is best way to get the solder off without hurting the little legs on the chips?
    "In Life, The Days Are Long But The Years Are Short..."

  2. #2
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    A well-tinned iron and some desoldering braid would be my choice. I'd leave the solder on until you've soldered the chips in their new home.

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    and, if needed, add some flux to the desoldering braid.
    Torfinn

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    I wouldnt be soldering them into a new home, I'd be putting them in the empty memory slots on some PCI Graphics cards I have, so getting rid of the solder would be the option I'd need.

    I can give the braid a shot, I just worry about crushing the small legs on those chips when I press down on the braid with the soldering iron.
    "In Life, The Days Are Long But The Years Are Short..."

  5. #5

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    If you have a vacuum desoldering gun that could be worth a try too.

  6. #6

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    Use liquid flux and a hot iron with a flat wedge tip. Brush the flux on the legs, turn the chip upside down, and put the iron on the tiny flat top of the leg and the heat and gravity will draw the solder down to the iron. The flux is the key. Clean the chip with alcohol or flux remover when done.

  7. #7
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    If you want to go the extreme route powder some low-temp fusible alloy, pack it around the pins and use a low-temp heat source (e.g. a PAR-38 incandescent spot lamp) to heat the part. Use a small hog-bristle brush to clear the solder+alloy off. I've used this method quite successfully on TQFP parts with very fine lead pitch.

    But I suspect you're just looking at a TSOP or some such.

  8. #8

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    My technique for this is a desoldering gun.

    I use a gun tip that will just fit over the leg and quickly heat/suck and then spray it with iso. I think in the end it heats it less than holding the braid down on it will. (keep the temp at or below around 600F)

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