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I am currently designing my first PCB to be manufactured by a fab (I am using JLCPCB). The base material that JLCPCB offers is FR-4 TG130.

In that design, I have a few wires that would need to be hand-soldered, potentially multiple times if reconfiguration is necessary.

Regarding durability, would it be better to use plated through-holes for that or similar sized single-sided pads?

Also, what is easier to solder to for beginners?

Only leads will be attached to that, so no through-hole/surface mount components.

The parts that are attached to the leads will be separately mounted to the case of the whole device, so pulling resistance on the pads/through holes will probably not be a big factor.

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    \$\begingroup\$ Don't rely on pads for pull-strength. But whether pads or holes you should have strain relief. If reconfiguration is necessary why not just use screw terminals or terminal blocks? \$\endgroup\$
    – DKNguyen
    Jun 30, 2022 at 15:49
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    \$\begingroup\$ Through hole screw terminals are dirt cheap, easy to change out wires and relatively hard to damage. \$\endgroup\$ Jun 30, 2022 at 15:53
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    \$\begingroup\$ Plated through holes are better easier more durable for soldering. But screw terminals are great if you have room. There are also non-screw terminals (spring loaded wire cage terminals where you push in a button then shove the wire in). \$\endgroup\$
    – user57037
    Jun 30, 2022 at 16:39

4 Answers 4

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Maximum customization:

Readymade "DuPont" style wires with female connectors on the ends, that mate to male 0.1" headers soldered on your board. That's the mess on the left part of the picture. These are also great for probing stuff, as it is possible to install a male header pretty much anywhere you can solder, and that solves the three handed multimeter problem.

enter image description here

For more robustness, the mains version: spring-loaded wagos. It's very easy to modify the wiring, and the high voltage bits are hidden inside, which is safe.

enter image description here

Regarding your exact question, from an "ease of prototyping" point of view:

  • Standard thru-hole pad

If you want to remove the wire, then put a new wire back in, then the problem will be that the hole is full of solder. You can always suck it out with the solder sucker, but if the hole was tight to begin with, the new wire still won't want to get in.

enter image description here

The solution is to make the hole too large for your wire. For example, 1.5mm holes for 0.5mm wire. This makes it much easier to experiment: just melt the solder and push the new wire through the melted solder blob. It will find its way through the hole very easily. Then angle the wire 45° so more of it sits in the hole, and finish soldering it.

  • SMD pads

That works very well. These SMD pads stay attached to the board in spite of the heavy transistors with heat sink because I put in holes inside the pads. So they're SMD pads, but with a via in the middle. You can also put vias in the corners too. The vias take up less space on the other side of the board than a full thru-hole pad. The solder fills the via and holds the pad to the board.

enter image description here

Then you can make a hole, and thread the wires through it. That will hold them and prevent them from wiggling until the soldered end breaks. You can also make 2 holes, slip a ziptie through, and hold a cable in place.

It's not pretty, but it's nice to be able to mess with the prototype without the wires periodically coming off.

enter image description here

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  • \$\begingroup\$ I'm not that brave :) These days, I make boards with plenty of machined open-bottom pin receptacles and use those to house through-hole parts where possible. They are pretty much custom solderless breadboards, with some/many parts soldered down, but the rest is plug-in plug-out style. I add extra connection points at most circuit nodes. The receptacles can also accept "Arduino" patch wires, breadboard jumpers, etc. I usually populate the receptacles as needed. In early prototyping I need more, later less, and for production hopefully 0 unless there are selected parts. \$\endgroup\$ Jul 1, 2022 at 18:50
  • \$\begingroup\$ That's a nice idea! I just put male 0.1" headers, and I have a collection of SMD resistors and whatnot pre-soldered on the mating female 0.1" headers, kinda plug and play \$\endgroup\$
    – bobflux
    Jul 1, 2022 at 18:58
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Soldering wires directly into holes in a PCB is not great- the solder wicks up stranded wire and creates a spot where the wire tends to bend and break off. For ease of re-soldering (assuming you don't have a good desoldering tool) you might consider laying the wire along the board (a rounded-corner rectangle pad) and passing the wire through an unplated hole in the board as a strain relief. We used that technique in industrial instrumentation and never saw failures.

It will be a lot less annoying if you use a wire with high temperature insulation so it doesn't melt back severely when you tin it.

Or just use a connector as most commercial products do, but you'll need a good crimping tool to make reliable joints from wire to connector.

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  • \$\begingroup\$ In case anyone wondered what an affordable but decent tool may be: I'm in love with the Engineer PAD-02 crimper set, Made in Japan. Probably the best value for semi-professional use where the $$$ terminal vendor's tools are not really necessary. The Engineer brand sells on Amazon. I'm in no way attached to them, just a happy camper here :) \$\endgroup\$ Jul 1, 2022 at 18:55
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In your case it might be useful to combine through-holes and pads:

  • through-holes are much more durable but are nasty to (re)solder to because they have to be cleaned from remaining solder
  • wires can easily be soldered to solder pads, but pads can come apart after some iterations.

If you have a through-hole surrounded by a pad you can easily solder a wire to it the "SMD-way" and still have a relatively strong joint if you make sure that the hole is completely flooded with solder (solder has to come out of the back side).

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    \$\begingroup\$ It is true that plated through-holes may have to be cleaned up before you can put a new wire in there. Although sometimes you can just melt the solder and push the wire through the liquid solder (if it is one wire at a time). \$\endgroup\$
    – user57037
    Jun 30, 2022 at 16:42
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One option is turret terminals. They look like castle turrets:

A photo of a Mill Max turret terminal

The terminal above is Mill-Max 2501-3-00-44-00-00-07-0, but there are of course dozens if not hundreds others.

In my hobby projects, I've used Useco 1390D-8 Miniature Turret Terminals, shown below. They are plenty tall to attach a wire to the bottom portion, while allowing clipping a probe/clip to the upper portion.

A photo of Useco 1390D-8 Miniature Turret Terminals

The common manufacturers are Mill-Max and Useco, at the very least.

Photo credits: Mill-Max via DigiKey, and eBay seller wnyhardware.

I'm in no relationship with any of the sellers, except as a regular customer.

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    \$\begingroup\$ Do you personally solder on those or just split the strands in two and twist them together right behind the turret? I'm not a huge fan of those but they seem to be widespread in RF stuff and I was wondering why (especially given that for RF wires are sometimes not stranded). \$\endgroup\$ Jul 5, 2022 at 22:40

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