6 Replies Latest reply on Sep 23, 2018 3:27 PM by Vladimir Urazhdin

    How to manage Global Variables in Assemblies ?

    Henk Bruijn De

      I have been reading many posts about managing GV's (Global Variables) in Assemblies, but have not found a clear solution which is robust (reliable), fast rebuilding and easy to apply.

      In my case I want to use it in SSP (Skeleton Sketch Part) Assembly type.

      I have read about linking a GV to an external file, but this seems a bit clumsy to me.

      Solidworks allows you to push and pull a GV from almost anywhere in the model (Feature tree), in- or out of context, which actually seems an invitation to circular rebuilds and or slow rebuilds.

      So far my I decided to push the GV's according to this picture;

      All of the GV's are defined in the SSP-part, and from there they can be pushed to equations in all other Parts, Sub-Assemblies and the Main-top-level-Assembly.

      It seems to work fine so far.

      lease let me know your ideas about this.

        • Re: How to manage Global Variables in Assemblies ?
          Henk Bruijn De

          I have tested some options and discovered that using GV’s (Global Variables) in an Assembly with Sub-Assemblies can be a mess, when not organized.

          I designed a special model to test some things. The model is a roughly a flexible hose with flanges and fasteners, showing a straight position and a bended position in different Configurations. I choose to use SSP method because it is well organized by default. Since the SSP-part is driving almost everything, it first seemed logically to put all the GV’s in the Equations of the SSP-part.

          All the Parts can pulll the GV from the SSP-part, and also the Main-Assy can pull the GV from the SSP-part.

          However, the Main-Assy has patterns which are controlled by some GV’s. If the GV is defined in an Equation of the SSP-part, than the information has to be pulled from the Equation in the Main-Assy and be pushed back to Feature in the Main-Assy. This seems not robust enough to me. The other option is to split the GV’s in the SSP-part and in the Main-Assy. This will be fine until you want to control the GV’s with Configurations and a DT (DesignTable). Than you have 2 different DT’s in 2 different files!  I decided to put all the GV’s in Equations of the Main-Assy. The model is included.

          Further thougts:

          • - is this the best way to handle GV’s in an Assembly?
          • - The labels do not scale nicely, do they need to parametrically controlled by the DT ?
          • - Ideally, the size of fasteners has to be also controlled by the DT (working on it).
            • Re: How to manage Global Variables in Assemblies ?
              Alexander Klammer

              Hi Henk,

               

              Looks like the best approach possible right now to me.

               

              Have you used this on a large scale already?, first look seems like the approach to go with. - Had a lot of problems with huge saving times at piping/media assemblies with external references to the respective interfaces in the buildings.

               

              Nevertheless changing the same dimension in numerous parts when modifying a design in monkey work style is no proper approach in any way either.

               

              When driving this further i think the limits are where a CAD Configurator comes in.

               

              BR

              Alex

                • Re: How to manage Global Variables in Assemblies ?
                  Henk Bruijn De

                  Hi Alexander ,

                  I have not used it on large scale, the model was just an example.

                  Actually I have decided to leave this subject untouched for the time being, because I'm running out of ideas to create a nice parametric model.

                  The combination of fasteners, labels and all other dimensions and configurations  is more difficult to manage than I thought.

                  Another dilemma thing:

                  If I manage the configurations for fasteners with a design table in the main-assy, than the fasteners have to be components in the main-assy. I'm afraid this will reduce main-assy rebuild performance very much.

                  Thanks.

                  Henk

              • Re: How to manage Global Variables in Assemblies ?
                Vladimir Urazhdin

                SSK works fine, but it's also possible to link Global Variables directly both ways Top Level <-> Parts/Sub-assemblies.