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I hope this question won't be closed as too subjective. I'd like to know best practice - how to make traces on universal PCB's with individual holes without traces (like the following image). My idea is to bend the ends of discrete components and use them to make traces to other components. Is this approach acceptable, or nasty? Although this is called "prototype" PCB, I'd like to use it for my simple final circuits (low frequency, low current applications), because I hope it will save time.

Universal PCB

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    \$\begingroup\$ I'm thinking about how I do the "layout" of the circuit for an answer, but I have a tip as well. Use a fine-tip black marker to trace out which holes are actually traces. It makes the board much more visually intuitive and can really help with debugging. You can also plan out the entire circuit this way to make sure everything fits the way you want it to. If you make a mistake and have to redo something just use some rubbing alcohol. \$\endgroup\$ – NickHalden Jan 16 '13 at 16:58
  • \$\begingroup\$ This is not really a PCB: it is a perfboard with solder pads. Do not use this. Get a PCB breadboard which has traces that you can exploit. There is at least one program to help with layouts on that type of board: VeeCad. \$\endgroup\$ – Kaz Jan 17 '13 at 1:36
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Protoboards are up to you how to use, if it works, it works.

The three common methods of using them is using jumper wire, solder bridges, or using leads. Or all three, depending on your needs.

Solder bridges take a lot of solder, especially long ones. They are good for two or three adjacent points.

Using the leads, or bare wire, is great for straight lines and buses, using less solder than solder bridges.

And jumper wire is best for when you can't/don't want to go around an existing solder joint.

It all really boils down to what you need. Of course, solder bridges can be very sloppy if you don't have practice at them. And using too many jumper wires or bare leads looks ugly and not well thought out. But this is your project, you can figure out how to mount them, and what's acceptable or not.

If you need much of either, what you really want to do is think about the placement of your components, move stuff around to minimize the need to use jumpers or long bridges.

enter image description here enter image description here

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    \$\begingroup\$ Another advantage of using wire like in the first image is it's a good way of using up left over component legs that would otherwise be wasted - I started using SMT stuff mostly because I got annoyed at the huge piles of snipped off component legs that THT results in. One other thing to be aware of with solder bridging is if you are doing long straight lines, try to do them bit by bit (letting it cool), and where possible, or zig-zag them. Otherwise as the solder cools and contracts it can warp the board. \$\endgroup\$ – Tom Carpenter Apr 26 '15 at 17:53
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Typically a board like this has components connected using wire from pad to pad. I usually use 30-AWG wire-wrap wire.

I often place components in such a way that leads that need to be connected are placed in adjacent holes. It's quite easy to create a solder bridge across two pads.

Sometimes I'll need to connect three or four leads. If possible I place these along a horizontal or vertical line of pads and create a solder bridge across the length of them. It's somewhat more difficult than a 2-pad bridge, because the solder will have a tendency to bridge only at the position of the iron, where the heat is. With a little practice, it's entirely possible to create lengthy solder bridges that span several pads. However, it can be ugly, waste solder, and is difficult to change. Multiple bridged pads is something of a hack, so while I do it sometimes, I don't recommend it for best results.

You can improve the bridged pad idea slightly, by adding stripped 24-gauge or smaller wire to the pads and using it to connect them. This image and caption/tutorial from brewpi.com:

Bridged pads

...use some naked wire for long tracks and just solder it to the board. For very short connections, you can do it without a piece of wire: Set your soldering iron to a lower temperature, and first put some solder on both pads. Then put some solder on your iron and tip in between the pads. When you are lucky, you’ll connect them. It takes some practice but it is definitely easier at lower temperatures.

I personally find bending the lead of a component to connect to another component on the underside (solder side) of the board less desirable than creating solder bridges. The reasons are:

  • the leads are thicker than the wire I would use instead
  • the leads are equivalent to bare wire and could easily make contact with an adjacent pad that should not be connected
  • difficult to remove/replace a component

In conclusion, if you need some bus lines, I would highly recommend spending a few dollars to get a solderable perf board that already has them as part of its design.

Perf board with bus lines

This 6.3" x 3.94" board is $5 at All Electronics.

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  • \$\begingroup\$ I made something once by solder-bridging on such a board. The key operative word being once. :) \$\endgroup\$ – Kaz Jan 17 '13 at 1:37
  • \$\begingroup\$ The Radioshack link doesn't work, can you find a replacement reference? \$\endgroup\$ – Kelly S. French Feb 23 '18 at 17:38
  • \$\begingroup\$ @KellyS.French Sure thing, I've changed the link to a Jonard Tools product at Digikey. \$\endgroup\$ – JYelton Feb 23 '18 at 21:49
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I know this isn't exactly an answer to your question but I thought it might help others. I still use perfboard a lot because it is more commonly available and I have a bunch of it laying around, but since I discovered stripboard, it is my preference. If you workout your layout, you can minimize the number of traces you have to create with soldier or wire. Instead, you use a drillbit to break the strips of copper where you need in order to create your traces.

This is very similar to what JYelton posted at the end of his answer but you can find boards like this all over ebay for dirt cheap.

stripboard

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It is possible and I have to admit I'm doing the same thing.. but I cannot recommend it because it's very hard to take the parts out later, when something's broken. The holes stick not that good to the board most of the time, so with too much soldering you would get the hole of your board. That's what happens sometimes when you're taking out parts again. So it's better to connect wires on the backside instead of using the leads of the components.

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    \$\begingroup\$ Easily mitigated by cutting the component leads before desoldering from the holes they go through, leaving the old leads as the interconnect - so in the replacement case it degenerates to using separate wires (the old component leads) while most of the time the component leads supply the wiring. \$\endgroup\$ – Chris Stratton Jan 16 '13 at 17:06
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    \$\begingroup\$ That is true but I find cutting the leads when soldered yet to be a bit hard, so I'd go with cutting first and using the leads as wires. \$\endgroup\$ – user17592 Jan 16 '13 at 17:12

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