On Sun, 2022-05-01 at 07:56 -0700, Rick Collins wrote:
The part I don't get is how they control where the plating starts and stops.? Looking at the image in your link, it shows what appears to be a cut out in the board edge.? The plating is not on the entire edge, but stops at a point.? I can discern no feature that controls this stopping point.? It is possible this point is defined after the plating by the final routing step cutting away the plating beyond this point.? The image is not clear enough to tell.?
I don't know all the details, either. But most PCB fabricators that I know of don't use your Gerber and Excellon files as-is - for a start, they add their production numbers to the silkscreen layer and usually tweak the copper layers to compensate for their processes - undercutting etc.. The drill holes are also not what the designer thinks they are either - sizes are adapted to what drills the fab actually has, and compensated for plating thickness etc.. There is quite a lot of back-end work that the PCB designer never sees and normally doesn't need to know about.
Tony Casey