Any onshape users there? I need undestand if only my issue , when try to export dxf dwg no have closed path and cam software as easel or makercam ecc no permit some operation on it, need make joined polyline before use. thx for info.
Maybe you can join it using Inkscape?
Yes I need make it but is a real boring work and lose of time… just see some cam read fine export…need try with cnc. Good of easel is good for beginners cnc users in any case onshape Added my request as enhancement.
In any case hope adding some tool for clean history…just arrived at 800mb for a project of 15mb… now copy it and delete old file. Other great absence are moving sketches/part from tabs… 
tried with export-import but no like result …continue to learn…
Copy sketches worked for me. alternatively you can export an stl and slice it with openscad cut command into a dxf.