Zone Fill not Connecting to Net Tie

I’m trying to connect two isolated GND pours together with a net tie however the zone fills do not go over the graphical polygon in the Nettie footprint. Images attached below:

What I want:

Net-ties have been implemented in a hackish way in KiCad.
When net ties were implemented, graphical items on a copper layer were completely ignored by DRC, and this could lead to an unrelated track being routed over the graphic item in the net-tie.

Later code was added to recognize graphical items on a copper layer, and a special keyword “net tie” was added to the “Description” of the net-ties so tracks can still be connected to the pad on the net ties.

A better implementation of net-ties is on the radar of the KiCad developers. It’s among the 1100+ issues logged on gitlab.

In the mean time you can right click on the zone, then select Zones / Add a Zone Cutout [Shift+C] and then draw a cutout in the zone in the form of a “C”.

You can also use Pcbnew / Place / Keepout Area and draw a “C” shaped keepout area. If you use a “keepout area” you also have to edit it’s properties to keep out copper pours.
image

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What version of KiCad are you using? See Help>About>Copy version info.

I have used net ties a few times and I do not remember seeing your issue. The net tie has pins and I wonder if your net tie is too long with the pins far into GND and GND1 zones?

The other thing is to make sure you specify solid zone connections and not thermal reliefs; maybe you are getting that…

If you look carefully at the first screenshot, you can see that the zone clearance is calculated from the graphic rectangle and not from the round pads of the net tie.
Pad connection has also already been set to “Solid”.

I did do a comparison between KiCad V5.1.x and KiCad V6.0.0-rc1.

If you put a net-tie in the middle of a zone (with “Solid” connection to pads) then it looks like this in KiCad V5.1.x. The clearance on the left is clearly calculated from the edge of the graphic rectangle.
image

If you do the same in KiCad V6.0.0-rc1 (Below) then the zone is not kept clear of the rectangle graphic. There is only a clearance around the other pad because that belongs to another net.
image


It just occured to me that a simple workaround for KiCad V5.1.x is to simply draw a track segment over the gap. Use a wide track and set it to “locked” so it does not get removed by KiCad’s interactive router.

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I think that sounds consistent with the idea that shortening the graphic line might help somewhat. But perhaps another method would be to make the net tie with long rectangular pads and a short graphic line?

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