Multi-net via alt. Net-tie Via

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Hey!
I’m using kicad version 5.{nightly} and I’m building a rather complex 6 layer PCB.

So I have 8 local ground planes that all needs to be isolated from the regular ground, these are at layers In1.Cu and In4.Cu. My issue is with connecting these with a starground to the regular GND-plane.

The schematic component “net-tie” is useless for three reasons,

  • I need a footprint connected to this
  • That footprint needs to be on top or bottom layer
  • That footprint can not be in “one point” or you can’t connect traces to it.

Is there a possibility for some skilled coder to implement a way to assign separate nets to the each layers a through-hole/buried/hidden via passes? Something (for example) like:
Hidden/Buried - Layers F.Cu to In4.Cu

  • F.Cu – GND
  • In1.Cu – GND
  • In2.Cu – GND
  • In3.Cu – GND
  • In4.Cu – Local_GND_1

But obviously resulting in a warning “Warning: Via acting as net-tie for layers XXX and YYY” (not an error, as this will obviously be on purpose).

OR some way to make net-ties into special markers which lets you, and warns you if you never, connect these with traces but will still put clearance for Cu pours? I know this might be troublesome with eeschema, but maybe it can be solved?

Alternatively this could be solved by not at all using net-ties, but rather different zones for the same nets? The issue is that keep-out zones has no priority but will affect all pours the same. If keep-out zones had priority you could create a keepout zone with higher priority than the GND pour but lower than the “local” Copper pours, this would still require some workaround for multiple “local” grounds next to eachother though.

Lastly would be to allow some kind of “keep-out trace” similar to programs what Altium or Eagle uses, which lets you draw “traces” that, instead of being copper are interpreted as negative copper, i.e. “no-net trace with 0 width and a clearance”.

Does anyone have any idea or solution to this?

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Alternatively an option to allow any number of nets to connect to a specific point, although I understand all this will mess with the clearance options.

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I’m working on precisely that feature, but it will be some time until it’s finished, because I have only little time and there are so many areas this touches.

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I checked out the link, that sounds rad! how about, instead of giving you a component to drag around, just give all nets connected by a net-tie the right-click option to “merge object with net: XXX” (where XXX is a sub-menu with all the nets connected to this object via a net-tie, similar to all the options for custom track-widths being a sub menu).

I assume one of the issues now is that vias act as one object/pad rather than “one object/pad per layer with their relative position fixed and a PTH through them”.

Right now my work-around will be the extremely sub-optimal solution to keep my buried via connected to GND, -> ignore DRC -> generate the Gerber files for all layers except In4.Cu -> change net for via to local_GND -> ignore more DRC -> generate gerbers for layer In4-Cu -> done.

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The problem here is the connectivity algorithm. As long as the object is not part of the net, you will have a hard time routing a trace there, unless you switch the PNS router to “highlight collisions” mode.

“One pad per layer” would solve your particular problem, but it would not work if on one layer you have both a zone and a trace connected to the same via, which is why I want to go the “pads and vias can be members of multiple nets” angle.

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