Fig 5 - Removing the device.  Notice the Long Tweezers


Now we’ll take a moment to talk about the importance of long tweezers.  Although during the removal of the IC, the heat gun is out of the picture, normally both the tweezers and the heat gun are both hovering over the chip.  Heat gun cooking, tweezers nudging.  Short tweezers means you will be cooking your fingers as well.  That sucks - get long tweezers.  The temperature required to melt solder is hot, and you should not expose your fingers to it for long.  You can even see that the ends of our tweezers are cooked to a dark grey - they have removed a LOT of IC’s.

After removal, you’ll probably need to do some cleanup.  Either components will have moved, or solder will have bridged across the PCB pads or the IC pins.  Just accept the cleanup phase and don’t try to half-ass it.  You can use a standard soldering iron for the cleanup, and solder wick (desoldering braid) is invaluable.  Below, we show a capacitor who was blown off his pad by the air.  You’ll need to look around for things like this, lest you end up with a board that mysteriously doesn’t work as well.  It’s no mystery - you screwed something up.  There are no such things as electronics gremlins that come in and cause glitches to a previously good system.  Go find the problem, fix it, and the board will work as designed.




Fig 6 - Collateral Damage


Only one capacitor coming off of only one pad is actually not too bad considering how close it is.  We credit that to the use of really cheap solder on this PCB that melted at a pretty low temperature.  Definitely not Lead-Free, as that stuff takes a little more cooking to soften it up.  Fixing the cap took about a minute to desolder and re-place it with a standard soldering iron.


Continued on Next Page… 

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