Exclude Copper Pour Under Trace?

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Hi all,

I have been having a few issues with a PCB that has tracks with differing impedances.
I have 100 Ohm Differential (fixed dimensions), and 50 and 100 Ohm single ended tracks where the dimensions can be altered.

I have each signal layer separated by a GND layer

Is there a way I can exclude the copper pour in the adjacent GND layer if a certain net is being used (only directly under the track)?
This is for the possibility of increasing the impedance of a track by effectively skipping a GND layer. Possibly also only in one direction, or on a specific layer.

This is a high density PCB, so I would prefer if it was using custom rules or possibly python, bearing in mind I have no experience using python with KiCAD.

Thanks.

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Easiest way is probably to select the affected trace, right click, and use create from selection option to create a rule area from the trace, select “keep out zone fill” only and the desired layer, deselect “delete source objects”. Use the hull option if you want it to expand beyond the size of the trace itself. This will create a rule area that does not allow gnd pour on the selected layer.

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Thanks for that, I had no idea it could be so simple.
Only took a couple of seconds to test out.