No net (floating) copper zone

Good morning all,

I have been using Kicad recently but very easily. It is truly an awesome program.

Despite everything, I have a question:

I create my ground plan which is good but I have zones which do not contain copper (normal because it is not connected to the GND). But I still want copper inside which will be connected to nothing (no net). So I created a second mass plan with the “no net” connection. Until then everything works. But when launching the DRC, I have errors (copper zone inside a copper zone).

How to avoid having these errors?

Steve

Did you set different priority levels for the different zones ?

The priority of the ground plane is 0 and that of the “no net” plane also 0. If I set it to 1, all the component masses are no longer linked to the ground plane.

and if you set it the other way around ? (1=GND 0=“No net”)

Are you refilling the planes? Are the ground planes actually connected to ground?

Having unconnected copper planes is a bad habit of some people.
Instead, try to make a usefull ground plane.
Often this can be done by making the clearance between tracks wider, so the gnd plane can simply flow through to your empty area.

Or sometimes push a few tracks to the other side (and use via’s) so the tracks do not cut the GND plane into little pieces.

If you’ve got a power plane on the “other side” you can also put a few via’s in the “unconnected area”, and KiCad will then recognise that area is also connected (After a re-calculate zones).

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Thank you for all your messages, but I can’t make these 2 ground plans. I reversed the priorities but either it is the ground plane connected to the GND or that connected to “no net”.

I have to place them both in the same priority but with DRC errors.

Here is a video that will be more meaningful than text. You may see what I am doing wrong.
Here is the video link :

As you were told it is bad idea to have a not connected copper fill.
If you place one via at the region you would like to be filled but GND don’t fils it then GND will fill it.

Thank you for the answer but as it is an artisanal circuit, I cannot place this via in small places.

So I’m going to do with it and have DRC errors.

I hope Kicad improved this functionality.

First, have you tried to arrange your tracks so that there’s more room for copper areas and vias, or so that an existing copper area can occupy more space and the nonconnected are is smaller?

Second, why not just leave it empty? Even if it’s etched at home, does it really matter so much?

Third, you can add a cutout to the higher priority zone. Then the lower priority zone can fill the space. This isn’t convenient if you need to move or change the zones later because you have to change the cutout manually, too.

Select the zone -> context menu -> Zones -> Add a Zone Cutout.

Your right.
In many cases tracks need not to go the shortest possible way and making them a little longer you can make the regions filled by GND bigger by closing to 0 the regions for not connected fill.

Often the design requirements for artistic reasons are diametrically opposed to industry standard requirements (for example for RF emissions and/or immunity). KiCad is targeted to the industry requirements so any artistic considerations are only secondary if even considered at all.

Unfortunately, this will have to be true. But it is important to know which DRC rules you are violating intentionally (for your artistic license) so you can pay proper attention to the ones that must remain inviolate (like manufacturing minimum trace widths and clearances or circuitry issues).

Unfortunately, that is like wanting a grammar checker to be improved to accept poetic (or dialectal) grammar for that novel your are writing where your artistic choices to break grammar rules really only apply to the work you are creating.

That said… There are actually times in circuit design where floating islands of unconnected copper is acceptable (for example flex circuits). Other features that are specific to flex circuits (gridded planes) may be coming in the future so there might be hope that floating copper islands might be included.