13 Replies Latest reply on Dec 15, 2014 9:58 AM by Erik Rotolo

    Zero thickness geometry

    J. R

      Hello,

       

      I'm trying out SolidWorks 2013, and I ran into this error. I'm attaching a file. I need to extrude two oposite rectangles on top of the box (left bottom and right top). SolidWorks says it can't because of this zero thickness.

       

      How do I work around this problem?

       

      It has to be:

      Merged result (ONE part)

      Corners of these rectangles have to coincident (no micro space)

        • Re: Zero thickness geometry
          Jim Sculley

          J. R wrote:

           

          Hello,

           

          I'm trying out SolidWorks 2013, and I ran into this error. I'm attaching a file. I need to extrude two oposite rectangles on top of the box (left bottom and right top). SolidWorks says it can't because of this zero thickness.

           

          How do I work around this problem?

          You don't.  Not with merged solid bodies.  You either removed the requirement for merged bodies, add material to remove the zero thickness or use surfaces instead of solids.

           

          Jim S.

          • Re: Zero thickness geometry
            Justin Strempke

            You won't be able to do it.  The zero-thickness error is having two coincident edges belonging to the same part.  There is not a work-around (at least that I'm aware of) without having multiple bodies.

            • Re: Zero thickness geometry
              Jack Van Gossen

              I have to echo the previous two replies. It can't be done with a merged solid body. The reason is actually rather simple - you couldn't manufacture such a part in the real world, either. It would require you to machine (or print, or whatever) a shared edge that is nothing more than a single mathematical line, hence the "zero-thickness" part of the error. Mathematically possible, yes, physically possible, not so much.

              • Re: Zero thickness geometry
                Rick McWilliams

                The zero thickness geometry isa serious cop out. I often have lofts that should fit exactly together, they share the same guide scurves and edges but there is some little warp that makes the zero thickness body. Solidworks needs to look a bit past the nurbs tothe underlying geometry to resolve problems like this. This is a Solidworks bug.

                 

                The whole idea that trimmed surfaces are ok is a bad idea. We would get much better surfacing with untrimmed surfaces. TSplines is a good concept. I use an add in to do complex surfacing. GW3D. Solidworks get in trouble by having such difficult geometry. Low order surfaces are the best.

                  • Re: Zero thickness geometry
                    Mark Biasotti

                    Hi Rick,

                     

                    Often times Zero thickness errors can be overcome by repositioning the connector or placing new ones.

                     

                    Mark

                      • Re: Zero thickness geometry
                        Rick McWilliams

                        Connectors are undimensionable geometry control. They sould do the logical thing, like connect verticies that are on linear sections that are parallel, but they prefer twists. I use guide curves instead of connector control. The connectors seem to get the idea when there are enough guide curves. Very often one is enough. I have never needed a twisted loft. Even with guide curves the zero thickness problem can persist.

                         

                        I have given up on solidworks for precision surfaces. I use an addin GW3D to generate smooth geometry. I am particulary fond of the conic surface. This surface is everywhere a conic section that is controlled by edge slopes and rho or a corner curve. They are perfect untrimmed second order surfaces. There is never a problem with edge conditions. No edge gaps or infintesimal radii. Ever since I have experienced real controllable smooth surfaces, I see flawed surfaces everywhere in models and real world.

                    • Re: Zero thickness geometry
                      Erik Rotolo

                      One Sketch, 6 simple steps

                       

                      Done!

                       

                      Or you can go one step further by linking the 2 fillet dims (so if you change one , both change)