Ver 6.0.7: placing a via attached to gnd

I recently upgraded to ver 6, so still learning! (and thanks for the various “how to upgrade” posts: my upgrade went nicely!)

In version 5, if I wanted to use a via to get some ground plane on the second side, I would just place a via over some gnd plane on one side: it would work out that it was to be connected to gnd, and all was good.

In ver 6, I see that it is described as “add a free-standing via”, and when I used it, it did NOT connect to the gnd, as I had expected… in fact, it cleared the space around the via! (which ties up with the description!)

I’m clearly missing something, but I’m not sure what!

I have done only one very small PCB (like 14x25mm) with V6 so have no big experience with V6.
Not sure what I am saying, but ensure that you:

  • have active layer at which you have the GND plane,
  • plane is filled.

Then I suppose if you place via then probably it will be GND via.

After you place the via, hit ‘e’ to edit & assign a net from the drop-down box.

After you place the via, hit ‘e’ to edit & assign a net from the drop-down box

Yup, that did it, thanks!

It should pick up the net automatically if the zone is filled.

I just added this via with ctrl+shift+v (freestanding via tool) and it picked up the GND net from the plane automatically. After refilling the zones, the via is still connected as expected.

If there is a second region of copper with a different net under the via (like a pad on the backside), then the via will pick one or the other.

So, here’s my PCB:

In V5, I would just drop a via on that bit of red in the middle: it would auto-detect that it was wanting to connect to ground, and would do exactly as you describe… fill that hole in.

So, I use the via tool, or ctrl-sh-v, to put a via there:

image

… and you might think "ah, yes, it’s connected ok to the ground plane there… but when I refill the zones, I get:

image

… which is NOT what I want!

If I go edit that via, it is not connected to any net. If I then set it’s net to be GND, then it works the way I expect:

Is there some ‘global setting’ that needs sorting out?

" * have active layer at which you have the GND plane,"

Ah, so before I had the BCu side (green) selected, but if I now try selecting the FCu side (red) and drop the via, it DOES connect automatically to the GND net, and works as expected.

I could swear that in Ver 5, it didn’t seem to matter which side was active, the via connected as expected! Not to worry, now I KNOW, I can work with it!!

(I’ll leave these last 2 posts here, in case it helps anyone else!)

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This is probably by design (and an improvement).
Consider a multi layer PCB with different zones on multiple layers.

Also: In your screenshots, the added pieces of GND copper on the green layer does not do anything useful. Consider moving either the red or the green tracks a bit to the side, and then use more vias, so all the GND pieces are stitched together.

Although it’s much better to move all the tracks to the same layer, and then have a continuous GND plane on the other side of the PCB.

This is an audio board, and experience is showing that any noise is inaudible. Yes, I could stitch it more, but it’s no big deal… although in that specific area there’s not many options.

(The main reason for adding in the extra copper is that is simply means less copper needs to be removed during manufacture. And it looks nicer!)

Yes, it WOULD be nice to have a clean ground plane, but I need some tracks to go on the other side… however, the majority of tracks are on one side, giving a very reasonable ground plane on the other, and in fact, where the audio is, it’s almost 100% groundplane.

As another comment: I just looked at the actual PCB’s I had made: they were made from version 5. It seems that something very minor must have changed when the layout was upgraded to 6: that specific area originally had groundplane, squeezing up between the track and adjacent pad. If, in 6, I slightly move the track, again the groundplane connects through ok.

You can make the clearance in the zone properties a bit smaller, so the zone sneaks in between the pads of the THT connector.

Although I usually modify the pads of such THT parts to use oval holes. Then the’re still easy to hand solder, while also leaving more room for either tracks or zones in between them.

It’s a bit of a bummer that the default settings of KiCad do not work for this.

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