Soldering Ground and 5v GPIO pins aren't connecting.

[mnelliot]

I'm finishing up soldering helders custom PCB and the raspberry pi together, and the 2 connections I need to solder aren't turning positive for continuity. I have not had any trouble testing for continuity until these 2 pins. If I were to run a wire from the holes, where would I connect it to? There appears to be 4 ground connections on the custom PCB which confuses me, and I have no idea where to look for the 5v connection.

[dryja123]

What kind of tip are you using on your iron, can you get it in the hole and give it a wiggle?

If you must run jumpers to the pads you can select any GND for ground, they're all connected. If it's the main 5v for the Pi you run the jumper from the GPIO to the main VCC pad next behind the physical start and select buttons.

I would strongly suggest using the correct soldering tip and reworking the holes. Look at Wermy's YouTube video where he even shows that you can rework the hole using a piece of wire.

Post back with your results.

[Psyicman]

Try tinning a bit of wire and sticking it into the holes a couple of times. It will help make the solder flow into contact better.

[Helder]

Also show pictures as if it's not sticking I assume the pads might have been burned off and there is no copper there to solder to.

[mnelliot]

Also show pictures as if it's not sticking I assume the pads might have been burned off and there is no copper there to solder to.

Yeah the pad was partially burned off on the ground connection. I got the 5v pin working, but Ground was still giving me trouble. I ended up attaching a wire from ground on the pi to ground right below the 8 pin ribbon connector.

My multimeter says everything works in tip top shape, so I figured this is my best option at this point

[mnelliot]

Also show pictures as if it's not sticking I assume the pads might have been burned off and there is no copper there to solder to.

See my reply, the pad looked pretty burnt from sticking my soldering tip in for a while, but I managed to get it to work by attaching a wire from the ground connection on the pi to the custom PCB.

[mnelliot]

What kind of tip are you using on your iron, can you get it in the hole and give it a wiggle?

If you must run jumpers to the pads you can select any GND for ground, they're all connected. If it's the main 5v for the Pi you run the jumper from the GPIO to the main VCC pad next behind the physical start and select buttons.

I would strongly suggest using the correct soldering tip and reworking the holes. Look at Wermy's YouTube video where he even shows that you can rework the hole using a piece of wire.

Post back with your results.

Thanks for your help! I managed to get the 5v connection working with persistence and sticking the tip of my iron in for longer. the Ground connection was the most stubborn one to work with though so I ended up attaching a wire from ground on the pi to ground below the 8 pin ribbon connector, I put a picture of this in my reply to Helder. The multimeter says everything checks out, so I'll roll with it and hope nothing disconnects.