Here's the OpenSCAD code: dxffile="207a.dxf"; difference(){ translate([0,0,-10])rotate_extrude(convexity=10) import(dxffile); translate([140,0,10])cube([300,600,300],center=true); }; Here's the DXF file: 207a.dxf <http://forum.openscad.org/file/n10598/207a.dxf> Here's the Preview: <http://forum.openscad.org/file/n10598/RotatePic.jpg> Here's the attempt at a rendering: Compiling design (CSG Tree generation)... Rendering Polygon Mesh using CGAL... CGAL error in CGAL_Nef_polyhedron3(): CGAL ERROR: assertion violation! Expr: e->incident_sface() != SFace_const_handle() File: /data/OpenSCAD/libraries-mingw64-master/mxe-w64/usr/x86_64-w64-mingw32.static/include/CGAL/Nef_S2/SM_const_decorator.h Line: 326 Geometries in cache: 5 Geometry cache size in bytes: 7177856 CGAL Polyhedrons in cache: 2 CGAL cache size in bytes: 0 Total rendering time: 0 hours, 0 minutes, 2 seconds Rendering finished. -- View this message in context: http://forum.openscad.org/Assertion-Violation-in-Render-tp10598.html Sent from the OpenSCAD mailing list archive at Nabble.com.

On Dec 17, 2014, at 14:20 PM, sguthery <sbg@acw.com> wrote: > Here's the OpenSCAD code: […] The challenge is that the DXF file touches the Y axis in one vertex. This causes the revolved volume to be non-manifold (volume collapses in one vertex). Unfortunately, our CSG engine doesn’t handle that. For the others: https://github.com/openscad/openscad/issues/1081 -Marius