Question How much of the copper channel is needed for soldering on a capacitor.

May 25, 2019
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In my attempt to remove the snapped off pins of a capacitor i drilled out one of the metal channels through the motherboard with a small bit. I wish to know if it is worth trying to solder in the new capacitor i bought, seeing as i damaged the metal tube and so the capacitor pin may not contact all the way through.
 
What you lose by not trying is the use of the motherboard.

You lose nothing additional by attempting to solder the capacitor in place; because solder flowing in, along the capacitor lead, might reestablish those via connections for you, again.

Drip liquid flux along the capacitor leads, so that it runs into the PC board hole. Use a 45 Watt soldering iron, heating the capacitor lead, and running the solder onto the lead, right at the point where it emerges from the PC board. Over-solder the connection as much as you can without shorting adjacent pads or PC board traces.

If the repair is successful, you will have gained a functional motherboard. If the repair is not successful, you will still have the non-functional motherboard that you have now.

In the future, don't drill-out component leads from PC boards, unless you are positive that you are dealing with--at most--a double-layer PC board.
 
Adding to AllanGH's answer: be careful. Drilling out the VIA with too large of a drill bit may expose both power plane and ground plane. Then cramming the hole full of solder would solder the two together with disastrous results to a PSU or CPU or memory or something else... or all the above.

Oh, it it could definitely create an interesting smoke show inside the case too!
 
True, but I am assuming a bit that is absurdly large, like a 4mm diameter bit, wasn't used. Anything below 1mm would be well within the typical margins for vias in power and ground planes. Probably the easiest way to "pre-test" for a short would be to do a continuity test between all V+ imputs and ground before ever applying power to the board in question, after the attempt.
 
...... Probably the easiest way to "pre-test" for a short would be to do a continuity test between all V+ imputs and ground before ever applying power to the board in question, after the attempt.

A nasty worn out HSS bit (like I'd find rummaging around my toolbox), hand-held in a power drill with (also typical) terrible chuck run-out, could also damage it badly enough to do a job on it I'd imagine. Only the OP knows if he centered up perfectly on the VIA with a fresh graphite bit in a precision drill press.

Testing for shorts is the best thing to do, of course. But if it were me, I'd eat the extra ESR and find a really close component lead at the same potential and wire a jumper to it on same side of the board.