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I am doing some assembly on a PCB which has a variety of SMD components. I accidentally got a little crazy with some paste on a large GND pad for an ESP32 component. I went to place the component on top and melt the solder, it appears to have oozed out of 2 of the vias located near the GND pad. I've checked with my multimeter and it appears the vias did not get shorted to ground, is that possible?

Am I safe to continue the assembly without desoldering the large SMD component (which I've failed to do so far) and removing the solder from the vias?

Example PCB

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  • \$\begingroup\$ A picture would be worth 1000 words here. \$\endgroup\$
    – Jim
    Commented May 9, 2018 at 21:58
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    \$\begingroup\$ As long as it doesn't short to another node of the circuit, or stick up so the IC won't sit right, it won't hurt anything. \$\endgroup\$
    – The Photon
    Commented May 9, 2018 at 22:08
  • \$\begingroup\$ Side comment: If that chip has a reason for needing the big ground pad, are you sure it's okay having the pad so weakly connected to ground (electrically) and without any heat spreading (thermally)? \$\endgroup\$
    – The Photon
    Commented May 9, 2018 at 22:10
  • \$\begingroup\$ If it has a big gnd pad like that, you probably shouldnt be routing vias underneath it... \$\endgroup\$
    – BeB00
    Commented May 9, 2018 at 22:18
  • \$\begingroup\$ It is possible that if you did not push on the chip in the process the surface tension was enough to "suck in" all the solder to the pads and vias nearby, maybe even raising the chip a bit over the surface. I'd recommend checking ALL the vias and traces in the area, and not only against ground but also between them. \$\endgroup\$
    – Maple
    Commented May 9, 2018 at 23:29

2 Answers 2

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Clearly the solder bump created by solder coming up through the via holes is going to cause a seating problem for the SMT part.

The fix for this problem is to get some solder wick.

enter image description here

Use the wick with a hot soldering iron to remove the excess solder from the problem vias.

enter image description here

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I have been there more than once..As frustrating as it can be, some good quality solder wick \ braid is needed here.

De-soldering pumps just don't seem to leave as clean of a surface.

One little trick I learned is just to add a small , very small amount of solder to the wick as you press it into the solder blob. Seems to pull the solder in quicker and more efficiently that way.

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