A result that I cannot understand

Author	Message
SunBakedWA Newbie Joined: 22/12/2023 Location: Australia Posts: 6	Posted: 03:23pm 15 Jun 2024       Hi OA47   Quote   as I have mentioned I do not believe that the issue is height levelling as the same pads are affected in different areas of the PCB blank. Just a thought, if its not the height of the bed and its the same pads in different places on the blank and we know the actual GCODE is correct then the copper foil must be higher in those pads than in the other areas as they would not be being milled away. So the question becomes what is making those parts of the copper foil be slightly higher? Is there any chance the etch resist may be causing the copper pads to lift slightly by soaking into the PCB backing (I would say G10 but I don't recall if you are using fiberglass PCB substrate) or causing the PCB to expand slightly and the affected pads are in board areas that are more exposed and thus more affected? Kind of throwing ideas now as you have eliminated other variables.... A test to see if its caused by the etch resist would be to run your pad clearing GCODE on a board that has not had the resist applied - if the same pads still get milled away then its not that! If they don't get milled away then apply the resist in your normal way and re-try. Just trying to suggest ways to break the problem down to eliminate possible causes. Good Luck