Extra trim lines

Hey guys, can someone tell me how to fix this…

The below image is a patch surface applied to an imported .dxf file, the yellow outline indicating the .dxf. From here I need to trim the holes but once I select the trim command I have those additional black lines appear. You can see on the central hole is only partially trimmed because the black lines are acting like trim boundaries.

How do I get rid of this?

Hello - please post a file with the objects, or send to tech@mcneel.com and someone will take a look.


Hi Pascal, I’ve discovered it happens when the outer line is not joined.