– Copied from customer email (@Esotech) –
I know this probably sounds a bit like savagery but - referring to the “small” switch module, are there any traces on mid layers between the hole and radiused corners?
Removing the PCB corners would allow me to easy accommodate either the small or rugged version of the switch modules in the prototype with only very minor changes and without altering or making a new chassis, or an adapter plate. This is what I would like to do, but obviously if there are any mid layer tracks routed around the outside this will not be possible.
Top left corner
Top right corner
Bottom left corner
Bottom right corner
You can see there’s a small sliver of ground plane on each layer on the outer side of the hole. So you won’t break any critical tracks when you do what you’re proposing.
However you do run the risk of planes within the layers shorting together. Not all the planes inside the board are GND, some are power rails.
That said, you probably should be able to do this, just inspect the corners after and check if you see any copper from the layers touching.
Also check for shorts using these testpoints. 1V1 and 3V3 are the power rails on the internal layers. If you don’t see a short there, you should be good.
It goes without saying that you’ll void the warranty by doing this
Based on your response indicating that the power plane is extended around the holes I have decided against removing the area of PCB in question and have modified the chassis instead