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Given a matrix board with soldering pads but no traces, how would you connect adjacent components (including the ends of the jumpers for longer stretches)?

Some possibilities I've come up with:

  • Solder the individual leads as usual, then bridge the pads with solder.
  • For each connection wrap one of the leads around the adjacent component's lead before soldering the two pads (ensuring there's more than just solder joining the two components).

I started with the former before I came up with the latter (which seems like at least an improvement), but I'm wondering if there's some even better solution I haven't come up with yet.

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4 Answers 4

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Here's another interesting method of perfboarding, this guy does it with SMD components and really tiny wires. He made a special little wiring pen for laying down the wires:

Progressive Wiring Techniques

example
(source: davr.org)

Personally I make solder bridges for pins that are in adjacent holes, for things further away I use thin wires (though not as thin as the ones above) in adjacent holes to the things I want to connect.

Top of my board:

board top

Bottom of my board:

board bottom

And no, I didn't just wire those pins all on the fly, I had drawn up a detailed schematic in advance. There's no way I could keep track of so many wires just in my head.

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    \$\begingroup\$ The first cabling is outstanding :-) \$\endgroup\$
    – Axeman
    Apr 14, 2010 at 17:39
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    \$\begingroup\$ Not sure it worth the time and headache compared to a 10$ PCB \$\endgroup\$
    – Damien
    Feb 26, 2019 at 10:26
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I have tried both the methods listed above, and I can certainly recommend the second one over the first. Trying to create solder bridges across the pads is not fun! The solder tends to blob onto the pads, and it does not like forming bridges. Heaven forbid if you have to make more than one bridge, then you end up creating one bridge, then destroying it as you try to create the second!

Perfboarding is an art, and requires a lot of thinking and forward planning to get neat. Never try to create solder bridges without something conductive in between. The best option is to use component leads to form the connections. Most through-hole components come with leads much longer than necessary, so you can use this to your advantage. If you need more material, you can use the snipped off ends of resistor legs, if you have them lying around. In addition, you can use hookup wire on the top of the board for longer connections. This is much less tedious than trying to carefully arrange multiple resistor legs along the bottom of the board, not to mention a better use of space.

If your circuit can be less compact, then you can use strip board (a.k.a. Veroboard) which has long continuous copper strips along the board. You can break the lines by grinding off the copper with a knife, scalpel or drill bit.

If you really want to be embarrassed about your perfboarding skills then look no further than: this. This guy knows the art!

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  • \$\begingroup\$ Thanks Dave. That's good advice. It's nice to know I'm not totally out in the woods. \$\endgroup\$
    – Redwood
    Apr 13, 2010 at 5:46
  • \$\begingroup\$ Your sentence about solder bridges made me laugh :-) Yes. IT IS FUN to make solder bridges... after some practice, you learn the correct timing, the correct temperature, the magic of a little blow on a bridge segment... it's an art :-) Some of my first prototypes also had DRAWINGS made with solder tracks. BTW: I can easily etch my own double sided PCB, but I like to build prototypes in this way also if I've already designed the PCB. \$\endgroup\$
    – Axeman
    Apr 14, 2010 at 18:07
  • \$\begingroup\$ I know it's old, but a search got me here. I also have trouble doing bridges. The melting solder literally drips through the hold before it wants to connect. It kind of "marbles" away from the insulating board between pads. 5m of solder gone, managed one horrible mess of a blob bigger than any component on the board... \$\endgroup\$
    – wcndave
    Dec 5, 2018 at 7:24
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I always bridge pads with solder, even for big circuits. It comes automatically after some practice.

These are two boards I've recently done (both of them deals with 220VAC)

alt text http://lbw.axe-man.org/solder/thumb/t_RELAYV2B.jpg alt text http://lbw.axe-man.org/solder/thumb/t_RELAYV2F.jpg

alt text http://lbw.axe-man.org/solder/thumb/t_RELAYV3B.jpg alt text http://lbw.axe-man.org/solder/thumb/t_RELAYV3F.jpg

I've built the second one directly from this breadboard version

alt text http://lbw.axe-man.org/solder/thumb/t_RELAYV3P.jpg

My first realizations were more "fuzzy" ... this was a 8x8 led matrix I made more than 18 years ago, with NO MULTIPLEX: each led was directly connected to buffer output.

alt text http://lbw.axe-man.org/solder/thumb/t_LEDB.jpg alt text http://lbw.axe-man.org/solder/thumb/t_LEDF.jpg

And this is my most "knotty" array cabling:

alt text http://lbw.axe-man.org/solder/thumb/t_FPGA.jpg

(full size pictures are on this page)

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  • \$\begingroup\$ Do you have an updated URL for those images? \$\endgroup\$
    – piojo
    Jan 17, 2018 at 2:59
  • \$\begingroup\$ Oh... sorry, I ditched that page months ago... I'll try to put them back online asap. \$\endgroup\$
    – Axeman
    Jan 17, 2018 at 11:03
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  1. Take a length of wire-wrap wire (30ga or so).
  2. Strip end of wire long enough to bridge the two pads. This leaves a short length of stripped wire and the remaining insulation, which now ends at point X.
  3. Solder end of wire to one pad.
  4. Cut wire at point X.
  5. Solder point X to the other pad.
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  • \$\begingroup\$ Wire wrap wire is perfect for this kind of thing. It is sometimes marketed as 'Kynar' wire. I can recommend it. \$\endgroup\$ Apr 13, 2010 at 21:49

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