19 Replies Latest reply on Dec 24, 2016 5:59 AM by Sergio Monti

    Mates breaking down????

    Dave Bear

      Hi all,

      I'm currently trying to add two new sub-assemblies to my main assembly but when I do it seems that nearly all of the mates in the sub-assemblies that the newly inserted sub-assemblies will be mated to break down and give me 'red-errors'. The existing sub-assemblies are fine prior to the new insertions but the frustrating part is that these have a lot of 'working' parts in them and these are the mates that are breaking down as well as others.

       

      The newly inserted sub-assemblies are NOT mated to any of the working parts of the existing sub-assemblies and they are only mated by basic flange to flange so why is this corrupting things in the way that it is and how can it be prevented?

       

      Regards Dave.

        • Re: Mates breaking down????
          Vladimir Urazhdin

          Hi Dave,

          How many (if any) "smart mates or parts" has this assembly or sub-assemblies?

          • Re: Mates breaking down????
            John Stoltzfus

            Sometimes mates don't show any errors till later, but try this....

             

            Open each file showing mating errors and go to the mate folder and start down at the bottom and delete the first "Red" error, if the errors still show move up one by one till the errors disappear, then check your feature manager tree to make sure that there are no " - " in front of the part name, if it is apply a different approach, a different mate, or select points rather than faces etc.. 

             

            What could of happened is maybe a surface to surface mate isn't quite parallel or too many mates etc.... Try to find a way to use 2 mates per part....

              • Re: Mates breaking down????
                Dave Bear

                Hi John,

                As it turns out, most of the offending mates are my 'cam-mates' (camshaft lobes to top of valve stems). You can't imagine how much this has p$%^&* me off!. 24 per head, times 2 heads. Aaaaagggggghhhhhh!

                 

                Why would adding something to the outer body affect these?

                 

                Dave.

                  • Re: Mates breaking down????
                    Jim Steinmeyer

                    Dave, if I recall correctly, you are allowing the cam to rotate and the valves/springs to move with the springs deflecting during the process. Correct? This may be the result of that. Try rebuilding 3 or 4 times (Control Q as Dan has suggested). Sometimes it seems that with flexible components SW needs to take a couple of runs at the calculations to get everything sorted out.

                    Just another reason to suppress not delete mates until you have it figured out.

                      • Re: Mates breaking down????
                        Dave Bear

                        G'day Jim,

                        You're absolutely correct buddy! I've just had another crack at it and inserted the two new sub-assemblies (exhaust manifolds) to the cylinder heads, did a CTRL+Q between each one and after the last one then saved it and ended up with no issues this time, well so far at least.

                         

                        Thanks Jim.

                    • Re: Mates breaking down????
                      Jim Steinmeyer

                      Suppress don't delete the offending mates. You might find that this is the one you want, not the other one that is causing the conflict. You can always delete the suppressed mates later if you want to clean them up.

                    • Re: Mates breaking down????
                      Paul Risley

                      Dave, I am going to assume this is your infamous motor assembly from previous posts. You posed a question about lightweight parts in a previous post. Now that you are on the cusp of full assembly I would say you should look into making the parts that are static/ not changing into lightweight components in your assembly. This is a common practice in large assembly once you have fully defined static parts turning them lightweight cuts down on resolving of the assembly. The red/ gold errors you will see on large assemblies are the softwares version of trying to rectify every scenario of what could and could not be. John's suggestion above is a valid one for fixing it, the lightweight option will clear some of the mating overdefinition and or causing the broken mates. Large assemblies are a tricky beast, but after a couple of go's at it they become easier as you find a workflow that will suit your design intent.

                        • Re: Mates breaking down????
                          Dave Bear

                          Hi Paul,

                          So it is okay within one assembly to have a mix of normal and light weight components then?

                           

                          Dave.

                            • Re: Mates breaking down????
                              Paul Risley

                              You can turn any part in any assembly lightweight. The benefit is no re-build on that part, which is also the downfall if you need to change it. So managing them is important. It is easy to turn a part from lightweight back to resolved if you need it to be rebuilt. Also Dan's comment about tangent mates is a valid one especially in large design mode. Rebuilding tangent mates on the scale of a motor where I am assuming you have a few is going to wreak havok on rebuild.

                              My suggestion if it is not to late in the game for you is to create tangent planes to the round surfaces you are holding tangent and re-mate to the planes if you can. Holding moving enviroments like this together is tricky but doable.

                              • Re: Mates breaking down????
                                Dan Pihlaja

                                Another one from the help files *grin*:

                                Lightweight Components

                                You can load an assembly with its active components fully resolved or lightweight. Both parts and subassemblies can be lightweight.

                                • When a component is fully resolved, all its model data is loaded in memory.
                                • When a component is lightweight, only a subset of its model data is loaded in memory. The remaining model data is loaded on an as-needed basis.

                                You can improve performance of large assemblies significantly by using lightweight components. Loading an assembly with lightweight components is faster than loading the same assembly with fully resolved components. Assemblies with lightweight components rebuild faster because less data is evaluated.

                                Lightweight components are efficient because the full model data for the components is loaded only as it is needed. Only components that are affected by changes that you make in the current editing session become fully resolved. You can perform the following assembly operations on lightweight components without resolving them:
                                • Add/remove mates
                                • Edge/face/component selection
                                • Assembly features
                                • Measure
                                • Section properties
                                • Mass properties
                                • Exploded views
                                • Physical simulation
                                • Interference detection
                                • Collision detection
                                • Annotations
                                • Dimensions
                                • Assembly reference geometry
                                • Section views
                                • Advanced component selection
                                When a component is lightweight, a feather appears on the component icon  in the FeatureManager design tree.

                                 

                            • Re: Mates breaking down????
                              Dan Pihlaja

                              Sometimes I will have an assembly that shows red or yellow errors on my mates when I KNOW that there are no issues.

                              2 things could have happened:

                              1) a global update just needs to happen: if this is the case, then a simple CTRL Q will solve the issue.

                              2) one of the mates might have "Flipped" when you added to the main assembly.  See if that is the case.

                                   and example of being "flipped" is when you create a tangent mate to the left hand side of a cylinder and the mate "flips" to the right hand side instead.

                              • Re: Mates breaking down????
                                Dave Bear

                                Thanks everyone for your prompt attention and helpful information......

                                 

                                Dave.

                                  • Re: Mates breaking down????
                                    John Stoltzfus

                                    I should have asked or rather I should have known that it's your cam mates - Again it comes back to choosing a different approach when it comes to mating cam related parts, I would never use the cam mate or a tangent mate, for exact reason of what you are experiencing.  On another post I had mentioned using a sketch of the cam path which you would already have and then add a point or use a point from the original cam sketch.  A coincident mate from a point to a line will follow correctly every time and not flip.

                                     

                                    I would change it, but it's your baby not mine, lol 

                                      • Re: Mates breaking down????
                                        Dave Bear

                                        Hi John,

                                        Yep, those cam-mates we discussed! But CTRL+Q fixed it and I can move on and get this thing closer to the finish line. I know next time though to do a sketch path, I just couldn't be bothered re-doing them all on this project, I'm getting quite sick of this thing! lol.

                                         

                                        But don't think the advice wasn't heeded............

                                         

                                        Dave.

                                    • Re: Mates breaking down????
                                      Sergio Monti

                                      Another reason for the error could be the following.

                                      The sub-assembly you are going to insert has got some parts having the same model name of other parts already used in the main assembly, but actually being a different model. I that case Solidworks will use the current model already present instead.

                                      I faced that problem in the past with bought-out component downloaded from internet.

                                      When using big assemblies, may be you use a component, i.e. a pneumatic fitting, more than once in sub-assemblies, but that fitting could be located in two different folders and having the same name.

                                       

                                      Sergio