Polysurface exported from AutoCAD opens as wireframe in Rhino

Hi all,

My colleague who works in AutoCAD is exporting these models as polysurface, however when I open these files in Rhino, I can only see the curves as a wireframe.

Furthermore, the curves are very stubborn. For example, I want to extract the face curves of one of the cogs. But I can’t join those curves together. I can’t project the curves to the C plane. Curveboolean fails in weird ways…

Anyone has an idea where the error originates ? Is it the export settings in AutoCAD or the import settings in Rhino ?

result of failed curveboolean

try drag and drop your .dwg into rhino viewport

That doesnt seem to change much, if anything at all. What is the reason for trying this ?

I see it now, same problem here. I cannot answer your question about the reason. But it is possible to extract a closed curve by selecting all curves, extrude into surface and intersect with a planar surface.

Hi @simon9
SolidWorks also sees nothing but curves in the file, so I’m guessing it’s an export issue - hopefully your colleague or someone here with AutoCAD experience can help you out.

Opened the file in AutoCAD, the models are blocks of lines/arcs not solids.

could you eloborate what blocks are in AutoCAD , please?

There’re only lines in the CAD file.

Google “blocks in AutoCAD”. There’s a similar concept in Rhino