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This board is a prototype for the project and is for testing. It is missing the soldermask and silkscreen layers, so correcting mistakes is very possible. The board was printed correctly, but somehow I missed one via (grr) from the top layer of copper to the bottom, and the software I used (ExpressPCB) of course doesn't have any checks for things like this.

I would like to know how to add my own via. There is no ground plane on this board because I used the bottom layer for traces to lower the size of the board. It is a basic 2 layer "prototype PCB".

Below you can find a picture of the portion of the board front and back with the trace ends circled. They are lined up directly over/under each other. I need to connect those two.

Top enter image description here

Bottom

enter image description here

The two solutions I'd imagine would work:

  1. Use a tiny drill bit or mill and drill a hole through, and make sure solder is filling the whole and touching both traces
  2. Just solder a wire to the top trace, wrap it around, and solder it to the bottom trace.
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I suggest you combine the two methods. Drill a hole near the traces and thread a thin bare wire through the board, lay it along the exposed traces by a few mm and solder it on both sides.

If you don't have such a wire handy, just strip a piece of stranded wire and use one of the strands

Nobody will notice unless they look very carefully, and it will be reliable.

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  • \$\begingroup\$ I'd agree with that - don't disturb the existing copper trace - just solder to it. But, why oh why no earth plane? \$\endgroup\$
    – Andy aka
    Commented Apr 5, 2014 at 20:10
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    \$\begingroup\$ @Andyaka I wonder what software it was.. I think I'd have to try hard to miss a via with Altium (it would fail DRC for sure) and I'm sure Eagle is equally competent when it comes to connectivity DRC. I do like polygon pour of ground and power.. with a little stitching you can almost get a 4-layer board effect with two layers. \$\endgroup\$
    – Spehro Pefhany
    Commented Apr 5, 2014 at 20:14
  • \$\begingroup\$ He might have used a mech eng package hence no thoughts about an earth plane!! I'd use Altium if I had the choice but I have to use mentalgraphics absurdity called PADs. \$\endgroup\$
    – Andy aka
    Commented Apr 5, 2014 at 20:16
  • \$\begingroup\$ This is a good suggestion, no sure why I didn't think of that. @SpehroPefhany this is ExpressPCB which is annoying proprietary software that doesn't let you import or export to or from anything. This is for school, so I'm using the software since the school pays -_-. As for why no ground plane, I wanted to cram this into as small area as possible and ended up using the second layer of copper for traces, so I just ran fat ground traces, as this is for prototyping & testing. \$\endgroup\$
    – sofly
    Commented Apr 5, 2014 at 20:18
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    \$\begingroup\$ The final board is already in Eagle/KiCad and hopefully will be fabbed nicely with ground plane and all :) \$\endgroup\$
    – sofly
    Commented Apr 5, 2014 at 20:29

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