11 Replies Latest reply on Oct 21, 2014 5:41 PM by Greg Fowler

    Part Not Meshing Due To Interference

    Edgar Stone

      Greetings all,

       

      Have been browsing these forums for a while now and they have helped me immensely. Certain little tricks and tips that I needed to continue with my design in SolidWorks I had found here with ease. This current problem I am having now, however, has been persisting for longer and I have not seen a topic that has pointed me in the correct direction as yet.

       

      I am quite new to SolidWorks Simulation and as such may not be very use to its abilities and things of that nature. The part I have attached have been giving me problems during meshing due to interference. I am not even sure to check what is actually interfering, much less to solve it. I would appreciate any assistance I could get on this. Possibly a hint on if the way I constructed my part was not well thought out. It may have been as I was just drawing as I got dimension from a very old standing machine.

       

      Please let me know a way to tackle this issue as soon as you get a chance to when you can. Thanks for all help in advance.

        • Re: Part Not Meshing Due To Interference
          Frank Krockenberger

          Edgar,

           

          I can get you started, I am on sw2012 so I could not load your file,

           

          go to tools, interference detection, make sure "treat coincidence as interference" is un-checked.

          Select your assy, select, Calculate.  this will show you what is interfering.

           

          Then,

          You can exclude a component or a shell from analysis by suppressing it and then remeshing the model. If a mesh exists and you do not remesh, the components will be considered in the analysis.

          -or-

          Right-click on the part and select Exclude from Analysis. The part is excluded from the study without suppression. The excluded part will be hidden.

           

          this is about it for me, I am in the learning faze.

           

          Frank

          • Re: Part Not Meshing Due To Interference
            Edgar Stone

            Hey Frank,

             

            Thanks for getting back to me so promptly. That option was not available to me at first as I was trying to run the analysis on was just a single component of the entire assembly. When I went ahead and brought in the whole assembly, I saw that option. It is the only component I have been having problems with and it is the most complex of the bunch. It is like the main body of the structure that every other components is attached to. Sad that you cannot open it as I would really love someone's hands-on experience with some of the errors I've been getting when trying to mesh.

             

            In any case I did run that interference detection for the assembly and it said there were none so that is not my problem. It is just saying that extrusions and cuts and so on that I have made are interfering with each other and that I cannot see and would like some help with,

            • Re: Part Not Meshing Due To Interference
              David Nagreski

              Edgar,

              Since your part is a multi-body part, the interference check doesn't work.  I just went through that with some imported multi-body parts that gave me the same error.  Since SW wouldn't tell me where the problem was, I guessed (I only had three bodies) and suppressed that body.  Then I redrew a new body based on the other two.

               

              Back to your problem, I tried meshing and then when the mesh failed, I suppressed the entity that it called out.  I didn't have time to study your design, but there appears to be some miss-matched solids.  When I tried to combine them into one solid body, I get the error of a zero length body.

               

              Try making a version that merges the various operations until you have a single body, then try to mesh it.

               

              Dave

                • Re: Part Not Meshing Due To Interference
                  Edgar Stone

                  Hey Dave,

                   

                  Thanks for the prompt reply. I have noticed that and addressed it by first suppressing it. Then when I do that, I realize it keeps popping up other bodies that it says to be interfering as well. I kept suppressing the different features as they pop up when I try to run the mesh and I realize that it seems to be affecting a lot of the model. If I should suppress them all, I probably would not have a model left. Why they are all interfering is what I do not understand. Have I really designed this equipment in such a unsolvable way? The thing is I built it off of an actual equipment so if I change much then I am changing the actual apparatus that I am trying to analyze.

                   

                  I am not sure how else I could have modeled this if I indeed needed to change all those features that are giving errors. Any direction on this problem would be of great help.

                   

                  Thanks,

                   

                  Edgar

                    • Re: Part Not Meshing Due To Interference
                      Jared Conway

                      Havent had a chance to look at the model but with interferences there are really 2 ways to deal with them, remove the interferences or merge all the bodies together.

                       

                      if you modeled things from a Real assembly is it possible your measurements were a little off resulting in small interferences?

                       

                      there is another topic about shells and weldments instead of solid elements but start with good geometry.

                        • Re: Part Not Meshing Due To Interference
                          Edgar Stone

                          Jared,

                           

                          Thanks for the reply. I doubt the dimensioning is the problem as I have retaken them three times and have had some of my peers check my work and turns out they get the same thing. Don't know the odds of so many checks and from different perspectives all coming up inaccurate but I think it would be quite low. As for merging the bodies, there are only some I can do as it also occurs during the extrude cuts as well. No sure if you can merge those but as I said I am quite raw at FEA.

                           

                          Removing the interferences (all of them) results in a drawing that is almost in no way similar to what I had originally which is not what I am trying to analyze so that's why I have been asking if it is maybe possible for someone to take a quick look at the part and see if my design methodology has been poor. I know many are busy but it would be greatly appreciated if one could find the time to.

                           

                          Thanks again.

                           

                          EDIT:

                           

                           

                          Hey Jared, is there a way to merge the whole body in one go as you were saying? I may need to explore this option. Shed some more light on this when you can, hopefully after getting a chance to look at the drawing.

                        • Re: Part Not Meshing Due To Interference
                          Greg Fowler

                          I'd suggest saving the bodies ("Save Bodies" feature) and building an assembly of the part.  Then you can use the "Interference Detection" tool...

                           

                          Also, if meshing fails, there's a handy diagnostic tool which tells you where the problems are.

                      • Re: Part Not Meshing Due To Interference
                        Edgar Stone

                        I went ahead and roll back my model to where I first started being able to mesh and I found that I made a bad extrude-cut that kept getting piled upon. Thanks to all for the many different ways to look at my model as I think it may have provided the breakthrough I needed.