Rhino export to .dwg Error

I am trying to export simple rhino geometry to .dwg and rhino is unable to export the geometry.
Find attach .3dm file and image of error msg.

Thank you!

BA_ST_02.3dm (340.7 KB)

I exploded the object and then exported the individual surfaces. One didn’t export, so that is the culprit. Went looking for the usual suspects - micro surfaces with no area or tiny edge length and I found one…


Remove that edge, join all back up, run _RemoveAllNakedMicroEdges to eliminate the micro edges left by the sliver surface when it joined to the others, then it will be a good, closed polysurface that exports fine.


Hello @omkar
I haven’t checked your specific file but I often get this error and it normally means that there is an object flagged as bad in Rhino. This could be a Poly, Surface or curve etc.
I always run the SelBadObjects command before exporting to DWG or DXF.
Bad objects will be highlighted.
FIX: The fix is normally just to Explode and immediately Join the poly.
If this still creates a bad object it can be down to seperating out the offending sub-surface and duplicating the border, untrimming and re-trimming a surface using the extracted border or remaking the sub-surface from the border curves.
I have also had instances of objects being flagged as BadObjects because of incorrect tolerances for the size of the surface or sub-surface.
Michael VS

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