23 Replies Latest reply on Nov 12, 2016 9:34 PM by Gian Flavio Violi

    Best Mate Practices Solidworks Assembly

    Joe Pickens

      I am working with a team of my peers to create a company wide assembly modeling standard. I am finding it vary hard to find hard info on mating robustness and calculation times.

      Is there anyone out there that might be able to guide me on getting this type of information.

       

      An example of a case i am trying to plea is.

      When mating parts with fastener holes. It is better to mate only one hole and then mate planes parallel or at an angel over mating two fastener holes concentric.

       

      I cant find any hard facts to plea that one way is better than the other.

        • Re: Best Mate Practices Solidworks Assembly
          Andy Sanders

          Use the least amount of mates possible that does the job.

           

          With fasteners I find it unnecessary to lock them of rotation.  Just constrain them to their respective holes with a concentric mate an the bottom of the bolt head to it's mating surface with coincident.

           

          Also, with fasteners, use the hole wizard component pattern as much as possible to avoid mating them everywhere.

          • Re: Best Mate Practices Solidworks Assembly
            Jim Steinmeyer

            Alin Vargatu is the most knowledgeable person I know.

            • Re: Best Mate Practices Solidworks Assembly
              Glenn Schroeder

              I'll disagree with you about using one concentric mate and then one parallel instead of two concentric.  If the holes don't line up for some reason, like maybe one Part was edited and the other wasn't, I want to know about it immediately.  And I do lock the rotation on concentric mates.  I like to know at a glance that all my components are fully restrained.

               

              As Andy Sanders said, when inserting fasteners, take advantage of the "Pattern Driven Component Pattern" whenever possible.

               

              Avoid stacking mates, such as mate Part A to Part B, then B to C, etc, although sometimes it's necessary.

               

              Use sub-assemblies when practical to minimize the number of top-level mates.

               

              Avoid mating to components brought in with a Pattern (Linear, Circular, etc.) as much as you can.  I've had a long-standing issue with those mates causing the Assembly to show errors for no good reason.  Sometimes a Ctrl+Q rebuild will fix them and sometimes it won't.

              • Re: Best Mate Practices Solidworks Assembly
                Arthur McRae

                I have an Assembly that has a layout that has points dimensioned where I want them then I made a single coincident mate from my sub-assemblies origin with axis' aligned. So I have a my top Level Assembly literally have as many mates as sub-Assemblies I've added.

                • Re: Best Mate Practices Solidworks Assembly
                  John Stoltzfus

                  The best Mates are locking components in with 2 perpendicular edges or 2 perpendicular sketches as shown below

                   

                  The red sketch is the Hole Wizard Sketch Profile and the Green is a McMaster C Bolt main sketch

                   

                   

                   

                   

                  The same is with the rails as shown below

                   

                   

                   

                   

                  Most people will use 3 or more steps locking in those parts...

                  • Re: Best Mate Practices Solidworks Assembly
                    Alin Vargatu

                    Any advice on mating schemes is directly dependent of the type of products you model and how they would be used by your team, by other teams or other 3rd parties (customers, vendors).

                     

                    Some companies do not us any mates whatsoever. Everything is fixed and all parts are build in the correct position in regards to the origin of the assembly.

                     

                    Other people would use one or more skeleton entities (sketch(es), part(s)) and mate all the components directly to the skeleton. That works wonders for revisions and is a very robust scheme.

                     

                    At the very least try to follow these best practices:

                     

                    1. Minimize the length of a mating chain. Find the fastest path to the main fixed component or to the assembly origin.

                    2. Do not mate components to hardware. Mate the hardware to those components. This way you would ensure a short chain of mates, while preserving the mating scheme when hardware gets suppressed, changed or deleted.

                    3. Avoid mating to patterned components. Patterns are calculated after the mate matrix is computed. You do not want to trigger another mate calculation.

                    4. Avoid mating to assembly features. Same reason as in item 3.

                    5. Avoid mating to entities (faces, edges, sketches) that are created in the context of the assembly. Same reason as in item 3.

                    6. Avoid mating to temporary axes. They will hinder you when you try to manage large assemblies with display states or SpeedPaks.

                    7. Avoid mathematical limit mates. Use Geometrical limit mates instead.

                     

                    Sorry, but I have to get in a meeting. Will continue the list in the near future.

                     

                    Disclaimer: These suggestions are coming from my own personal experience. I welcome any input in this regard.

                      • Re: Best Mate Practices Solidworks Assembly
                        Glenn Schroeder

                        Hello Alin,

                         

                        I see a couple of yours match mine (1. and 3., and thank you for explaining why not to mate to patterned components).  I must be smarter than I thought.  However, I saw you advised against mating using temporary axes, and I have seen others give the same advice.  I don't do that often, but I do occasionally, and have never had any issues with it.  I don't use Speedpak, but do often have Display States in my Assemblies.  Can you please elaborate on that relationship if you have time?  Is it just the lag when displaying the temporary axes?  I only turn on the temporary axes long enough to place the mate, then turn them back off, since turning them off doesn't suppress the mates.

                         

                         

                         

                        Glenn

                          • Re: Best Mate Practices Solidworks Assembly
                            Alin Vargatu

                            Don't be modest, Glen. I learn every day something new, reading your entries!

                             

                            Display States are super useful for large assemblies, when used in conjunction with the option for not loading hidden components when opening assemblies. Also, for unloading hidden components once the assembly is open.

                             

                            The best thing about this functionality is that there is no need for the crazy mate management needed when using configurations. When you suppress a component, its mates are suppressed. When you hide and unload a component, SOLIDWORKS applies some magic to preserve the position of the other visible components mated to the hidden one. It is a thing of beauty!

                             

                            Unfortunately, there is a bug when temporary axes are used: SPR# 933480: After using unload hidden components, mate error shows for mate defined by temporary axis and does not solve.

                            Also, for SpeedPaks, you cannot select a temporary axis for preservation, correct? So all the mates referring a temporary axes will be lost when the geometry gets speedpacked.

                             

                            Logically, what is the point of using a temporary axis instead of the cylindrical or conical face that generated it? We should mate to the most robust entity and a child is always weaker than its parent!

                          • Re: Best Mate Practices Solidworks Assembly
                            John Stoltzfus

                            If I could, I would like to add to your list....

                             

                            8.  Suppose you're working in a large assembly and you need to add another part, do yourself a huge favor and isolate the two parts you're mating, especially if the assembly is busy or rather a large amount of parts.  How many of us mated to the wrong part only to throw errors later, when you isolate, it can be more of a personal lifelong relationship , when we mate wrong there are or will be issues later..................

                             

                            9.  Whenever possible establish "Mate References" to your interchangeable components, make life easier.

                            • Re: Best Mate Practices Solidworks Assembly
                              Dave Bear

                              Great info, thanks Alin.

                              • Re: Best Mate Practices Solidworks Assembly
                                Gian Flavio Violi

                                To shed further light into tip # 3.

                                 

                                What I do often is getting all the parts mated before doing the pattern matrix, then include those components that would end off mated to the mirrored component in the pattern matrix itself. This is specially useful when using Toolbox hardware. If you want an example look at this.

                                 

                                Also, If you find hard to remember all comments made by Alin about what gets computed first, just look into the ASM model tree. It computes from top to bottom (as a general rule).

                                 

                                Green is the mate matrix.

                                Blue is Pattern matrix

                                Yellow is a Mirror Matrix

                                Magenta (or whatever color that is) is another set a Pattern Matrix.

                                 

                                Regards,

                                GF

                              • Re: Best Mate Practices Solidworks Assembly
                                Roland Schwarz

                                When placing a fastener that holds part A to Part B, I try to "cross over" my mates. If the fastener is on the Part A side, I put the face contact on Part A and the concentric mate on Part B. It's easier to detect misalignment when it happens.