Makerverse SMT Protoboard: creating bridges

Support Product Questions
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TLDR: what’s the easiest way to use the pads on the front of the protoboard to create traces? I think I should be able to just join up the pads on the front of the protoboard and create a trace through to each button, but what’s the best way? I’ve tried:

  • solder paste: once it melts surface tension pulls it up onto the separate pads
  • regular solder: the same thing happens, unless I put a heap on, and then it’s a bit higher than I’d like

Would conductive paint do the trick? Something else? Do something to the board to get the solder to stick?

Back story
What I’m making it a board to add some 3 buttons and a https://core-electronics.com.au/neopixel-mini-3535-rgb-leds-w-integrated-driver-chip-black-pack-of-10.html to the Pimoroni Inky pHat | Core Electronics Australia, for details on where where I’m coming from see here: GitHub - baralong/inky-gadget: Scripts etc for the pi zero with inkyPhat

I’ve cut a board to replace the black plastic bit in this:

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It’s all pretty flush so the protobaord is sandwitched bwtween the case and the PHAT, I’ll be putting kapton tape on both sides just to be safe. That also means I’m trying to keep things fairly low profile. The buttons and pixel fit to the left of the PHAT as the case is wider than the PHAT

Based on Inky pHAT at Raspberry Pi GPIO Pinout I’m connecting the neopixel to pins 1 & 7, then the bottons to 27, 29 & 31. One of the handy ground pins will connect to the ground pour (saving me from having to connect to multipl grounds or crossing the traces.

I’ve managed to attatch the neopixel to 3 pads on a board (I don’t need data out) using solder paste and hot air (much trial and error as it’s my first go with SMT), but it covers the pads completely so I can’t drive it yet.

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Hi Doug,

I find making bridges can be a bit easier with lead-free solder, it relies a lot on the flux to make things flow well and when you burn all of the flux out it behaves a bit like clay.
The main steps I take are:

  • Make sure your workspace is well ventilated
  • Especially with SMT, use a fine tip soldering iron
  • Turn the heat up a bit more

I’m keen to see how you go!

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Hi Doug
A piece of tinned solid core copper wire between the pads to join will help the bridging process without using excess solder. With modest currents 28G wire would be adequate. Purchase a small roll of “Kynar” wire. It is good for this sort of thing and is silver plated so solders readily. It is covered so will have to be stripped being careful not to nick the actual wire (otherwise it is likely to break).
If Core don’t stock it Jaycar have it Cat no WW4344, WW4345, WW4356.
Cheers Bob

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Hi Bob,

Thanks for the tip, that Kynar wire is great! I gave it a try yeaterday, so much easier to do the bridging now. I wish I’d known about it before, but you don’t know what you don’t know. In hindsight I could have made do with a standard perf board, but the SMT Protoboard is pretty and the ground pour is very handy. I also got a smaller soldering tip, that helped too

Anyway, thanks again :smile:

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