2 Replies Latest reply on Mar 16, 2012 2:01 PM by chris clouser

    Import issues, does anybody...

    chris clouser

      have trouble importing iges and step files?

       

      Do you have a problem importing a file and you get errors when you analyze the geometry and sometimes surfaces where there should be solids?

       

      I think quite often it is due to the Zero Thickenss Geometry Error.

       

      When we try to import geometry from another CAD system that can handle ZTG or even an assembly that has been turned into a part, it may fail due to the ZTG Error.

       

      This happens to me all the time. 

       

      for instance, if one was trying to import a roller bearing, and the bearing was saved as a part in another CAD system (NOTE: it could not be saved as a single part in SolidWorks, unless it was a multi-bodied part, because of ZTG), then there is an anomaly where the bearing actually touches the bearing race.  This is a single line of tangency that SolidWorks can not understand.

       

      Because of this, SolidWorks users are handicapped when they need to import geometry from other CAD systems.  I spend a tremendous amount of time trying to clean up imported CAD models to use in SolidWorks because of this.  Often there is no way to fix it and I am left with a part that has a bunch of solids in it (parts which SolidWorks did understand and convert) as well as a bunch of partially-formed surfaces (parts which SolidWorks couldn't figure out).

       

      Myself and others have also posted dozens of other problems due to the ZTG error.

       

      When will SolidWorks figure out this ancient problem?????

        • Re: Import issues, does anybody...
          Lenny Bucholz

          To be honest I don't want it fixed, as a machinist there is no way in hell I can make what you are asking the software to do, it will always blow out and make burrs....BAD MODEL PRATICES...!!!

           

          Model the way it needs to be machined, don't be lazy.

           

          Just my opinion

            • Re: Import issues, does anybody...
              chris clouser

              I hate to tell you this Lenny, but you're very small-minded.  There's more to life than machining and there are zero thickenss examples where machining would not result in blow outs (am I blowing out your mind right now!!??).

               

              Have you ever welded something?  There are times when you put edges together and weld the parts together.  Imagine two pieces of angle iron back to back and touching along the corner.  Thats really simple and straightforward to draw, it is a physical reality, and nicely weldable.  SW forces me to either interfere the two profiles, put a space between them, or go multi body.  What if I don't want to?  Have you ever designed a weldment in SolidWorks with more than three parts?

               

              There are times when you injection mold things with zero thickenss.  Have you designed any injection molded parts?

               

              Rapid prototyping doesn't care about zero thickenss.  Have you ever designed any RP parts?

               

              Sometimes sheet metal parts bend up so that the edges touch.  Have you ever designed or built any sheet metal parts?

               

              And there are artists using solidworks for 3D art who may benefit from the ability to do zero thickness.  Do you do any artistic work with SolidWorks?

               

              Do you do any advanced Cosmos analysis?  Anybody who does will have run into this problem when trying to simplify models by joining assemblies or multi bodies into single bodies.  Have you ever done any complex FEA?  Have you ever used any boolean operators on your models, such as the COMBINE command?

               

              There are times when CAD is used for designing theoritical things, such as optics.  Have you ever designed any advanced optics?  Focal points are ZERO THICKNESS!  It is NOT SOMETHING THAT WILL BE BUILT but it is VITAL TO ENGINEERING ANALYSIS.

               

              Also, there are times when a zero thickness feature is is the easy way to get to a final part that is "machinable".  If you roll back the part, there may be a ZTG, but by the time the part is done being modeled, it is gone.  I'm not allowed to do that, why?

               

              Pro E and Inventor have no problem with this type of geometry.  Why should SolidWorks?

               

              When I hear a machinist with your excuse, I realize that they are not the cream of the crop.  Below you will see a picture of an injection molded part where there are two opposing cylindrical voids.  The first one is a SolidWorks FAIL and the second is ProE.  This part is perfectly fine as an injection molded part, and also, there are some decent machinists out there that can make this part to three or four decimal places without any blow out or burrs.  Why don't you try it for fun.  We would all like to know if you can do it.

               

              And let me ask you another question, what if I create a part that is zero thickness but I add .00000001"?  The part will be fine in SW but you will still have the same flippin' mess as if it were ZTG.

               

              Maybe you and others need the software to guide you, but I don't need it telling me how to design a part.

               

              It's sad that you think that having to "fudge" your model away from an ideal dimension to something "almost" ideal is a GOOD MODELING PRACTICE.

               

              Please don't tell me what is a good or bad modeling practice.  And I don't want SolidWorks telling me either.

               

              And if you want to call me lazy, I'll put my modeling skills against anybody.  I have over 30,000 hours on SW, many of the features you enjoy in SolidWorks, such as multi-bodied parts, were suggested by me, and I reguarily build models in excess of 20-30,000 parts.

               

              It's very sad that there are others like yourself who can only understand their little corner of the world.  It disappoints me that I have to explain all of this to you.  And it disappoints me much more that I have to explain it to SolidWorks.

               

              zero thickness.JPG

               

              SUPERIOR PRO.JPG