want to see a crazy rework? here's a SAS RAID controller card that ran into a little problem. 🧵 
two capacitors got ripped off the board. not only that, but they took the pads with them.
these are series AC coupling capacitors used for the high speed differential data lane. this means the layout is critical.
view under the microscope. the squigglies on the lower left are there to lengthen that trace so that it is exactly the same length as the other trace in the pair. somehow i have to install these capacitors, with no pads, without changing the length of the traces.
first task is to verify the capacitance. i'd expect them to be 0.1uF or maybe 0.01uF. they measure 0.078uF. call it 0.1uF.
so here are the replacements glued down. these are 0402 capacitors.
a scalpel did a great job removing the solder mask on the traces. i need to solder wires to them.
soldered! that was a bit tedious. i had to use a very fine soldering iron tip and a pair of very tiny tweezers.
after removing the flux and adding a tiny bit more glue, this is what it looks like. you can barely see the wires even when you zoom in!
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