Tips for converting to 4 layer from 2

I’m a fairly new KiCad user and am still fumbling around a bit. I have 20 years experience with Eagle and can bang out boards practically in my sleep so it’s a bit of a culture shock.

Anyway, I imported a mature 2 layer design from eagle and want to convert it to 4 layer. One (maybe 2 ground layers?), power layer and 2 signal layers. Pretty straightforward. I think I just add 2 layers and copper pour the ground one. Then add the vias for ground connections. Then move the power traces to the power layer, again with vias. So, it seems like a fairly simple, if plodding, approach.

Am I missing anything here? Are there any things I can do to make this go faster/easier?

Nope, that’s pretty much it.

4 layer boards are much easier to design then 2 layer boards, as you can have both a continuous GND plane and plenty of room to route all your signals. (Until you start doing 10.000 ball BGA’s and similar).

You’ll need some time to get used to KiCad, and learn the ways to use it most effectively.
You can use the U and I shortcuts while hovering over a track segment to select portions of a net, and then delete it, or use the E shortcut to edit your selection to move it to another layer.

While you’re re-visiting this PCB, have a close look at all your decoupling capacitors and their connections.

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I would just make two ground layers and replace the ground traces with vias, if you’ve already maanged to route your power traces.

Thanks. Though, I was hoping for a magic macro so some such…

Every IC has some decoupling already, super close to Vcc and Gnd/Vss pins though with a ground plane I might get even closer which is what I think you were referring to.


Yeah, probably 2 ground planes but this is the start of a number of feature additions component changes so I need to clear some space for more traces which is why I’ll look at moving the power traces (3 different voltages) to one of the groundplanes.

A magic macro for doing what exactly?

It’s all much guesswork, because I have no idea what your board looks like. but adding 2 layers, removing the GND wires and connecting them to your new GND plane is probably somewhere between 10 minutes and half an hour of work for an 80*80mm board which previously fitted on a 2-layer PCB and therefore can’t be too difficult. Before you can do it in that time you will need to spend some time learning KiCad.

Can you recall how much time it took to learn eagle the first time?
Learning KiCad will take much less time. As a lot of the time goes into learning what you can and what you can’t do while placing Footprints and Routing them, and those conditions are pretty much the same.

KiCad’s Interactive router is also awesome. Learn to use it, and your approach to routing the tracks will change over time.

Have a look at the “cheatsheet” for KiCad shortcut keys.

The FAQ section of this forum: has a lot of good tutorials for lots of specific tasks in KiCad, and is a good place to start reading if you want to learn about specific tasks.

If you then start re-routing the rest of the board because you can make shorter connections because the GND is no longer in your way, that easily sucks up much more time.

TIP: If not already discovering this…
• Select the desired layer with Tracks to move (to other layer).
• The ‘E’ shortcut works Only on a Full Track, not a segment. Thus, select all segments (holding shift-key), then Right-Click>Properties and change the Layer as desired.

Then, you can move them/redraw them…

[EDIT] Also, in the 3D viewer, turning-on the Ray Tracing (though Slow) will reveal the traces on the Inner Layers…

(I had trouble doing this until realizing must select all seg’s of the track)

Thanks. About halfway done. I started using E and then decided I’d get better results just deleting the tracks and rerouting them. Thanks for the Ray Tracing tip - saves hiding/showing layers like a madman!

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