I have a QFN which we are adding after process. (it was not available the day we ran the 4 prototypes.) We have removed most of the solder on all the pads, My plan was that a LITTLE solder on the center pad would wet and center the device (using a gel flux) with our BGA hot air rework station. Then we would touch each pin with a tiny iron to make the pad connections. Well we had it nicely lined up on the gel paste, then reflow was good, but it shifted (nice and square) ONE SET OF PADS offset. Rev two of this attempt will be to put less gell flux on, and a tiny dab of paste the pads, hoping to have the PADS do the alignment. Any better suggestions out there? I was actually expecting my 1st approach to be just fine. Peter
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