AnsweredAssumed Answered

Why can't SolidWorks figure out simple mating tasks?

Question asked by Tim Lewis on Oct 28, 2015
Latest reply on Oct 29, 2015 by John Stoltzfus

I have a screw that I want to mate with the hole it is supposed to thread into.  For some reason, SolidWorks doesn't like this.  Sometimes, I can get it to mate without error (even after rebuilding and saving), but then an error randomly appears later after I've created a mate on a seemingly unrelated part.  Sometimes I can get the error to go away by deleting and recreating the mate, but it typically comes back after adding a part or creating a mate somewhere else.  Sometimes the error says the model is "Over Defined".  Other times, the error says that there is "No Solution Found". As you can see below, the mate is not particularly complicated.  It's just holding a circle (i.e. the end of a screw) that is already concentric with a hole in place (concentric with either the circle at the bottom of the hole or with the sides of the hole).


Overdefined.JPGNo Solution Found.JPG


Ultimately, the point is that it really appears that SolidWorks is too stupid to figure this out.  After all, how hard can it really be to figure out that two things that are already concentric need to be kept that way?


To say the least, if you sense some frustrations here, it's because I've run into this before and wasted a significant amount of time trying to eliminate the problems only to have them unpredictably disappear and reappear at random times later.  To be clear, there have been a few times that these errors have identified a slight misalignment of two sets of holes that I've been trying to align, but in those cases, the error doesn't go away when the mate is recreated.  Furthermore, I've confirmed that the spacing of the holes being aligned with these screws are spaced correctly.  All that to emphasize once again that there is no discernible reason for these errors.


My Questions:


My specific questions are:

  1. Has anyone else run into this issue?
  2. Is there something I could be doing that would cause this?
  3. Can someone please help me figure out what is causing this so I can stop tearing out my hair?

Any help anyone can provide would be greatly appreciated.