6 Replies Latest reply on Dec 23, 2014 8:43 PM by Ernst Hediger

    How can some Parts be moving in assembly without any relation?

    Babak Shei



      I've recently just started to appreciate how nasty and grimey solidworks can be when it comes to having flexible sub-assemblies. I've attached the assembly file, Can someone please confirm so that I know its not only my version of SW, that when the gears are rotated the table moves erratically on its own, even though there is no mate between the two.

        • Re: How can some Parts be moving in assembly without any relation?
          Robert D.

          worked fine for me. rotated gears on leg of table and nothing happened other than gear moving.

          • Re: How can some Parts be moving in assembly without any relation?
            Justin Harwell

            Ok the part labeled "two sided table" does move up and down for me. Using the wheels as the guide, it is mated as such, you could add a mate to hold it into place, or lock it. I did also notice at least in my file the table is sitting up at a near 45 degrees, and that may cause issues,


            • Re: How can some Parts be moving in assembly without any relation?
              Paul Cullen

              I opened the assembly in SW 2014 and had no problems. I rotated the gears and no other parts or assemblies moved

              • Re: How can some Parts be moving in assembly without any relation?
                Ernst Hediger

                You are not alone on this issue!

                I have had the same problems when I was on 2012 and 2013.

                Background info, I am working on an assembly in the mid 400 parts and over 3000 mates. SW warns me I am close to a large assy., so at times I load light. If it makes any difference I have a Dell Precision M4600 I7 quad core 2.5 MHz 8/16 MB ram laptop running Windows 7. At times it bogs down and crashes w/o warning. I suspect not enough installed Ram. If I catch the warning signs I stop and do a reboot and that seems to help.


                I have multiple subassemblies with moving suspension and  steering "flexible" parts.


                The A-frames are concentric mated at the pivot and left unmated to allow up and down rotation. As I moved the front A-frames up and down, the seat, a totally unrelated feature and not mated in any way to the A-frames would move forward and back. If the seat didn't move the opposite side A-frame would move up and down, or the steering would rotate. I have inquired with a tech at a local reseller and he did not have a clue!...no help. It can be frustrating beyond frustrating.


                That issue was accompanied by several other issues. Maybe you have these issues as well and didn't mention them.

                1)The rod ends which were initially brought in as a "flexible" assembly had to be unassembled and brought in as individual parts because SW would throw fits over them, spazzing and locking up. It took some trouble shooting by suppression to finally decide to unassemble them. It screws up the BOM, but eliminates the rod end spazzes. Conclusion: SW 2013 doesn't do flexible assemblies well!

                2) The shocks with Min/Max moveable length (extendable rods) had to be suppressed and replaced with a temporary fixed distance mates at the shock mounting bolts because SW threw fits over the min/max length mate. Conclusion: SW 2013 doesn't do flexible assemblies with  Min/Max mates well!

                3) The moving parts, like the A-frames and steering intermittently freeze up or refuse to mate. After several hours of fighting with SW trying everything you can think of the program "snap"s and everything works as though nothing was ever wrong. Conclusion: While SW is just a program and not human it can have an attitude called "Moody!"


                I upgraded this fall to 2014, (I am currently doing more Simulation testing than design intensive model changing work).

                Since the upgrade SW has settled down a bit. I have not run into any more issues with moving subassemblies.

                From my experience SW 2012/2013 doesn't handle flexible subassemblies, Min/Max mates, or moving parts well at all. SW had no help for me. I suspect bad software or corrupted programming. My best advice is to upgrade to what I think are more stable versions.


                I still have issues with intermittent "frozen" A-frames and the inability to make the last rod end mate, but 2014 so far works better on larger assemblies than 2012/2013 ever did.

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