4 Replies Latest reply on Jul 11, 2013 8:21 AM by michael.weinberg

    Self Intersecting Polygons

    Ned.Dempsher

      Wondering if anyone has run into problems with self intersecting polygons and slivers causing problems in down stream tools?

      We have had translation problems (into ICX for example), seen abnormalities in PI downstrean tools such as Ansoft SIwave and abnormlities in gerbers.

      Has anyone run into similar problems?

      What was the root cause of these problems and possible fixes?

      This has caused a lot of additional time and headaches our part and any experience you have would be greatly appreciated.

      Ned

        • 1. Re: Self Intersecting Polygons
          longliang.dai

          I met the same problem while import the gerber file to CAM350 that is created by Boardstation  , but i  have not checked reason .

          I need help for this action.

          • 2. Re: Self Intersecting Polygons
            fagrondin

            Ned,

            I had the same problem doing custom IDF's ( converting tracks and planes ) from BoardStation or Expedition to mechanical tools.

            All the problem were due to rounding or precision on the MCAD tools. trying to close the polygon it would miss or overlap and generate the same

            error message ( very small, 0.0001mm or more ). Changed the precison on the MCAD tools to be smaller when reading files and I think added a pass

            on the IDF to search for x/y inferior to a certain distance between 2 successive lines and round them to the same point so it would be continuous.

            And would check that first line and last line of the polygons were identical to close.

            Not sure if it helps but might give you some pointers.

            Good Luck.

            Fred

            • 3. Re: Self Intersecting Polygons
              a.thomasson

              If you have access to the Smart Utilities tools in Expedition you can allways try the "Outline Optimizer" on polygons to fix these problems.

              • 4. Re: Self Intersecting Polygons
                michael.weinberg

                If you don't use the Smart Utilities tool, enter Draw Mode, turn snap on and "trace" over the offending polygon with the add polygon tool. Once properly established, delete the original polygon.