I am not suggesting that this is a real current requirement. I was told this back in the days of solderwave and when there was a lot less attention to storage of PCBs and components before assembly
What is missing in KiCad Gerber file setup is the ability to include any layer - one or many - as input to the file generator. Gerber is dumb - it has no idea what you are feeding it - copper, text, graphics, etc. There are many instances where one needs this capability. Multiple but separate grounds is a common example - at some point they need to combine; known as a star ground. So you draw the ground nets, or planes, on separate layers and combine them at the Gerber level using some sort of a graphic “bridge” to tie the nets together without giving DRC a massive headache. Workarounds like this require the ability to generate Gerber files that can contain multiple layers. Most modern systems have this capability - look at Eagle.
An alternative method is to draw what you need on an inner layer and communicate with the CAM department at your fab house, requesting the appropriate Gerber files be combined at that level. It’s very easily done with modern CAM software.
Good luck! - bdh
If you are brave then yes.
The correct way to do this is with so called net ties (Allows connecting two grounds of different names at one specific point. So you can have an AGND and DGND and connect them at one point. Or you can have GND1, GND2, … GNDn and connect all of them at a single point using n net ties.)
Agreed. “Some sort of a graphic” = Net ties. Are there net ties in KiCad?
I erred in stating that different ground planes had to be on different layers. Many times they are on the same layer. We didn’t always have net ties or graphics. I used to run a captive prototype shop at a large company back in the early to mid 70s - pre-PC. Our engineering folks had one of the new-fangled CAD systems which they used to make colossal errors that sometimes had to be corrected by an engineer running into the proto shop with a roll of red mylar tape and quickly making manual changes to the artwork positives. Things have improved slightly since then…
Right now kicad does not support net ties as first class tool so one needs to go via a workaround of using symbols and footprints. (The next release will add net ties as a separate tool making them more powerful.)
Symbols are in the Device lib and footprints in the NetTie lib.
Simply search for net-tie in the symbol addition dialog.
Something to keep in mind is that the net tie workaround is limited to outer layers because footprints are limited to outer layers.
On an inner copper layer you would use tracks drawn with “ignore drc violations” plus possibly graphics on that copper layer to achieve something similar to net-ties (even worse than the footprint workaround as drc will complain about it and you can therefore miss a connection that should exist.)
Related to the original question, maybe it would help:
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