DXF import problems

PARTNER/ASPAN can import DXF files, but the import has the following limitations:

  • the DXF should be generated in a format compatible with AutoCAD 12, 13 or 14. Most CAD makes these DXFs.
  • the DXF could contain the following entities: lines, arcs, 2D polylines, ellipses, 2D splines (NOTE 2). You may export text using a trick: see NOTE 1.
  • the DXF must not contain blocks. If the DXF has any block you must explode from inside AutoCAD, using the AutoCAD "_EXPLODE _ALL" command.

NOTE 1: the SPLINES algorithm used by PARTNER/ASPAN is different from the 2D NURBS SPLINES used by AutoCAD, so you may experience some differences. If you want a closer match you must convert SPLINES to POLYLINES. To do so: export the drawing as a DXF in AutoCAD 12 style (R12 DXF). In this DXF the Splines will be converted to POLYLINES. That's all, but ... you will notice that the drawing will become Huge: a 12 Kbytes Spline drawing becomes easily a 2M Bytes DWG. Further PARTNER/ASPAN may give you the following error: "Reached the maximum number of routings". If you don't get this error you could notice that PARTNER/ASPAN becomes slow and the Part Program Generated by PARTNER/ASPAN is very big. If you want to avoid this error or huge Part-Programs, please change the Spline tolerances BEFORE exporting the DXF as R12 DXF. Set the Knot Tolerance, Control Point Tolerance and Fit Tolerance to 0.01 and not the default 0.0000001. When AutoCAD r13 converts the drawing in a r12 format, it converts a spline in a 3D polyline (not imported in PARTNER/ASPAN via DXF). Suggestion 1: - Use the PEDIT command, selecting the polyline to be modified; - use the SPLINE option of the PEDIT command to refine the polyline (with a zoom you can see how the polyline change). It should be noted that the polyline is still composed of lines but more accurate. With this procedure the number of entities in the drawing may increase dramatically and, when converted in DXF and imported into PARTNER/ASPAN, it may exceed the max number of entities allowed. Suggestion 2: - use the EXPLODE command, selecting the polyline to be exploded in its sections (this and the following steps are necessary to transform the 3D polyline in a 2D one); - use the PEDIT command, selecting one single section of the previously exploded polyline; - at the prompt of converting into a polyline enter YES; - use the JOIN option of the PEDIT command to join all the section of the previous polyline, selecting all its section (now the polyline is a 2D one). - use the FIT option of the PEDIT command to refine the polyline (this option is only available with the 2D polylines). The polyline is now composed of arcs approximating the original curve, and you can export the corresponding DXF to PARTNER/ASPAN. The same suggestions apply to AutoCAD r14.

NOTE 2:

  1. You have to set the "AutoDesk DXB file plotter driver" as a printer device (AutoCAD command config).
  2. Then you can print the drawing containing text to the DXB file.
  3. You must now import the dxb file back to AutoCAD using dxbin. After import, the text has been converted to lines.
  4. You can now make the DXF file.
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