Hi citroelf,

The reason you don't see anything might be because the files were saved from Rhino as 'SaveSmall' which means there is only mesh data available no NURBS data which MoI uses.

The only option you have is to find gems with NURBS data in them which would include generic CAD formats like IGS, STEP and SAT.

Alternatively you can use the Obj23dmWireframe utility http://moi3d.com/resources#Obj23dmWireframe_converter which converts OBJ to a .3dm wireframe which then if the curves are planar you can run Construct > Planar on them to create surfaces then join them to make a solid.

The latest beta V3 does open DXF files if there are splines and curves in the file, I tried opening some on the site you linked and the same thing happens with them, empty, must be only mesh data.

There are few jewellers here on the forum they might have links to better resources for you.

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