Thanks Charlie, I know about the difference between 2d and 3d DXF export. The problem is different. In the attached image you can see what the problem is I encounter. The DXF export does generate true arcs (non segmented) code, so far so good, but... In both the DXF to G-code translators I use (free ace converter and USB CNC, the last one a professional program), the G code based on a DXF file generated by sketchup pro 8 results in a mirrored output. [image: KbBS_dxfexportbulgeincorrect.PNG]