I have a board with many of the same donut/ring shaped pad like those described in this post:
These pads exist on the front and back of my board, but when I generate the gerber files the pads on the back layers (mask, paste, and copper) are incorrectly generated as filled circles instead of rings. The front generates as expected. What’s worse, I can generate gerber files and sometimes some of the pads on some of the back layers generate correctly (i.e. pad 1 on the back mask might generate correctly, but copper and paste for pad 1 will still be incorrect, pad 3 on the back copper might generate correctly, etc.), then I can immediately generate gerber files again without making any changes and the back pads that generate correctly will have changed. I’m kind of at a loss so any guidance or even best guesses would be appreciated.
I found that checking “Disable aperture macros (not recommended)” in the Plot dialog fixes my problem, but I’m unsure why, or if checking that box can/has introduced any other problems.
Attached is a zip file containing a test project with two PCBs, one which tests a donut footprint and the other which tests an “almost donut”. The “almost donut” (which is similar to the footprint I was having trouble with) has a 0.0001" section removed from it, making it kind of a “C” shape. I wasn’t able to duplicate the problem exactly as I was seeing it, but I think the problem identified by the attached test project is the same problem. In the case of this test project, even checking “Disable aperture macros” doesn’t prevent the almost donuts from being filled in, and the problem exists on the front layer as well as the back. The true donut, however, works as expected.
When I created the footprint I was having problems with I started by creating a donut shape using two concentric circles, which doesn’t work. That is what lead me to create the “almost donut” shape. I didn’t realize until today that I should have used the line width feature to obtain the correct donut thickness, thus negating the need for concentric circles, or concentric arcs in the case of the “almost donut”.
Yes, I typically draw my shapes in SolidWorks and then import the graphics. I included the SolidWorks and DXF drawings in the test project (in the “graphics” directory). Sorry I didn’t mention that. I see what you are talking about though. When I make the same shape in KiCad I get “fp_poly” points, not “gr_poly” points. I haven’t tested to see if my original problem exists when the shape was created in KiCad.