Single sided circuit boards

I am trying to recreate PC Boards for some vintage equipment, all these boards are single sided, I can find no way to get KiCad to just have 1 Copper side, when I go to layer setup the program defaults to 2 copper levels even going to custom wont allow me to have a single sided board. Is there any work around to force only routing on the non component layer.

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You may want to try “Design Rules” > “Layers Setup” and select “Two layers, parts on Front only”.

What exactly do you mean “force only routing on the non component layer”?

pcbnew itself does not enforce routing at all. You decide when (and if) to place vias or Through Hole pads and you decide the layer on which to route. As long as you route on one side (say F.Cu) and flip footprints of TH devices to the back side, then I think this will accomplish what you want, no?

Are you trying to do SMD devices and routing on one side only or Through Hole devices on one side with routing on the other? Or some other arrangement?

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OP says “vintage” so probably not SMD. You only have to route on one side. Your choice. If you don’t route or specify a ground plane on a side then there will be no copper. In short, if you don’t tell the program to put down copper, it won’t. I just designed a single sided board. I just did all the routing on the bottom side.

The only caveat is that if you close between sessions, routing will default back to the top layer. In my case though the traces are red for front and green for bottom so there is no mistaking which side I’m on. You can turn off visibility on the right tool bar of a layer. I’m not sure that helps you though. I think you could still lay down some traces and just not see them.

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Even with a single layer PCB, two layers are needed for EDA design. The top layer to locate the physical part, and the bottom layer to run copper pads/traces.

Also probably not plated through hole NPTH to the pad on the bottom layer.

For an accurate duplication, this means custom footprints for every part in the design.

Is your design new enough that copper was used as silkscreen? If so, that is an additional bit of information you will need to learn and apply.

If I am copying a vintage single layer NPTH board, I would actually make a two layer design, but simply not use the F.Cu component side. Then:

  1. I can use existing footprints, which use PTH holes
  2. PTH solder joints are much less prone to dry joints
  3. Most hobby/protype fabs don’t offer single sided
  4. I can always use the B.Cu plot to expose and etch my own board, drilling manually
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[quote=“Sprig, post:4, topic:7122”]
. . . Also probably not plated through hole NPTH to the pad on the bottom layer.

For an accurate duplication, this means custom footprints for every part in the design . . . . [/quote]

How authentic do your designs need to be? The thin, straight traces; accurately squared (or mitered) corners; and uniformly spaced traces produced by modern software EDA tools will differentiate your boards from the “originals” (laid out with tape on mylar) and can be spotted from half way across the room.

As already mentioned, it’s a trivial matter to place traces on only one side of a board with KiCAD. The fab house will probably still require Gerber files for both the top and bottom sides, even though one file will be completely empty, since they only produce boards with two or more layers. I have never used the feature, but the “Footprint Editor” lets you specify through-hole pads with copper on only one side of the board. Getting those pads produced with non-plated through holes may take a little effort - some low-cost fabs produce plated-through holes for ALL holes up to a certain size. (Typically around 6mm (1/4").) If you edit a pad to create a “vintage” look like this, you should probably also un-check the appropriate “*.Mask” box.

“Vintage” equipment didn’t have nearly the proliferation of component package styles that we have today, so an entire design might use fewer than a dozen types of footprints. And, they will be rather simple, straightforward footprints so creating an entire library of “vintage” footprints isn’t a formidable task.

Dale

From what I know, this is usually done with electrolysis plating; and if there is no copper on one side, there should be no through hole plating.

I reserve the right to be horribly wrong on this issue.

True, but these cheap FABs are geared to producing double sided PTH boards. Single sided belongs to a different world of paper based boards (another vintage issue) and very high volumes.

Good points about plated through holes. We don’t know the OP’s scale of production and budget though or even if they are being designed to be produced. The older boards tolerances may be loose enough to do themselves. Otherwise, if they buy up an entire panel worth of production then that simplifies things.

I think the OP wants to force the autorouter to only one layer.
For manual routing is easy.

As I never use the autorouter, I can’t help here.
May an autorouting user enlighten the OP?

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You can set the autorouter not to use the F.Cu layer, but if the OP is cloning a vintage board, manual routing is the only way to get close to the original tracking

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Just set a keepout zone where you don’t want tracks.

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would you like to comment on my post…

https://forum.kicad.info/t/1-sided-auto-routing-in-kicad/8602

I don’t use auto routing or know which one you will be using. You may be surprised to learn you can actually do this better yourself. An autorouter may give up in the scenario you list. Don’t assume there is a solution. There may not be. My circuits are generally quite simple and I lay them out as I go. I don’t wait for the end. This means a lot of rework along the way but generally improves the layout in terms of less clutter.

A post was split to a new topic: Single sided circuit boards in KiCad 7

The moved post is probably useful, but warrants a new topic instead of appending to a 6-year old topic.