17 Replies Latest reply on Apr 11, 2013 7:16 PM by John Sutherland

    Sketch losing relations to blocks

    David Suelflow

      I have a sketch in an assembly which is used to drive the geometry.  Within this sketch I have a couple of blocks that are linked to files.  These blocks are also used in various parts in the assembly so their use seemed to be a good idea.  Update the block and Voila! all is well…  Yea, not so much.  Every time I make even a simple change the block every relation and dimension attached to them goes away and needs to be reattached.  Even if I just change one dimension in the block (and thus not changing the element names) everything is lost.  Is that normal or am I doing it wrong?

        • Re: Sketch losing relations to blocks
          Filipe Venceslau

          Hi David, I've been having the same issue...my feeling is that it has to do with the block being linked...and somehow...everytime it "refreshes" it's link or something, the relations are lost...

          Have you found a solution for this? This seems like a bug, maybe we should submit a bug report so solidworks.


          I'm curious to know how you worked this out...



          • Re: Sketch losing relations to blocks
            Daen Hendrickson

            I am using SW2010 SP5.


            I am having the same issue with sketchs with blocks loosing relations.


            In my case, I am simply using the Save As (Save as Copy) function to make a new part. Part A is fully defined. Save AS to Part B. Open Part B and the sketch with the blocks has lost all relations.



            • Re: Sketch losing relations to blocks
              Jason Hogue

              We are having the same problem and I was just about to post this question on the forum.


              We are experimenting with using blocks as driving geometry in multiple components of an assembly.


              Eg,     Create an overall profile as a sketch with important features, save this sketch as a block.

                        Insert this block into a part and create the necessary geometry/features.  Do this with multiple parts

                        Create the assembly with these created parts.  All parts should fall into place and be linked to the block

                        Any updates to the block should be flected in the parts



                        No external references to another part

                        Potential improvements in resource usage due to the above

                        No read/write access issues if multiple people are working on the various parts (eg same as using a weldment profile)



                        Individual parts do not automatically update, especially when viewed in the assembly

                        Need to open each part and regen (not a huge problem so long as the number of parts are limited)

                        Changes to the block cause references to be lost as stated in the earlier post.

                        Note, not all referneces are lost but the ones that do drop off, are lost every time we change the block.

              • Re: Sketch losing relations to blocks
                John Sutherland

                Pack & Go fails to pack blocks.  This suggests a weakness in SW's handling of linkages to blocks.  Your problem may be inherent in SW.

                  • Re: Sketch losing relations to blocks
                    Denny Metcalf

                    Pack and Go will pack up the blocks if you have them linked to the original file.

                    Basically, it will pack up anything that is in the references:

                    [File] > [Find References...]


                    Back to the original question...


                    This has been driving me nuts for a long time now. I really want to be able to use blocks but they are so tempermental that even looking at them the wrong way makes them want to break all relations (with you).


                    I wonder if their implementation is anything like how SolidWorks arbitrarily "assigns" a number to a feature when you are placing mates or picking edges for flanges, etc. I didn't think so at first because you can actually look at your relations and see that yes, in fact, Line 6 of the block is coincident to Line 22 of the sketch... so why do the relations break. This makes even the insertion point option feel rather worthless.


                    Filipe, how are things?

                      • Re: Sketch losing relations to blocks
                        Filipe Venceslau

                        Denny, try unlinking the block and see if you still loose your relations. I understand you probably don't want to do that, but I have a feeling that may be the issue.

                        I don't really deal much with blocks, the only time I did, was when I created a macro to automatically bring in blocks and mate them, and that was when I ran into this issue. At the time I decided it to be better to unlink the block to it's original file and was under the impression that these relations being lost was somehow related to that.

                        So give that a try...


                        Things are going FFFFFine...I mean...hectic. lol...I'm getting back into school and have so much to do...never enough time in a day.

                        Kind of sad for getting away from this SW / Automation / API enviornment...but I'll still be around once in a while.

                        How are things with you?

                          • Re: Sketch losing relations to blocks
                            Denny Metcalf

                            Filipe, yes if the block references are not linked then you don't have any problems with losing sketch relations... but in many cases that defeats the purpose. I already knew that updating the block would break the sketch relations but sometimes it's a necessary evil to link them anyway. Usually my blocks don't change often so I keep them read only but yesterday I needed to update one that I had used in several locations. All of the instances worked great but are now free to float away, which is pretty dangerous.


                            I wouldn't dare classify this as a bug... instead I think of it as a feature that lacks a certain, logical functionality.


                            Over here I've been supporting production and trying to pave the way for a transition from AutoCAD to SolidWorks. Pretty soon I will be giving lecture on fundamentals of modeling and try to get the department working with SolidWorks. Hopefully I haven't scared anyone too much with all of the expletives that have emanated from my cube walls over the last several months as I've tried to determine how this tool can be useful for us and what should be our suggested design practices.


                            Good luck with going back to school, I'm a bit envious. Often I wish I could be a full time university student forever (only not having to work full time as well this time around). Don't worry about getting away from SW, if you're anything like me you dream in CAD.

                              • Re: Sketch losing relations to blocks
                                Darryl Daniel

                                I just posted this same problem in another post.  For me, I'm not linking the blocks and I still lose all block relations within the master model every time I do anything to the maste (i.e. rebuild, save, etc).  What's even worse, is that in my assembly, instead of just giving me an error showing that the constraints have gone away (or have moved) it actaully makes up completely new references and my components end up in the wrong spot without any warning.  To say this isn't a bug would be a huge mistake in my opinion.  Not only is this a bug, it makes blocks compeltely un-usable in the manner that we all want to use them.  I'm using SW2011 x64 (SP5.0)

                            • Re: Sketch losing relations to blocks
                              John Sutherland

                              "Pack and Go will pack up the blocks if you have them linked to the original file.

                              Basically, it will pack up anything that is in the references:

                              [File] > [Find References...]"


                              The references do not include the two blocks which define the sweep and thus the part.


                              The blocks were Made in seperate parts which are also not in the references of the sweep part.


                              Please explain.



                          • Re: Sketch losing relations to blocks
                            John Sutherland

                            "Within this sketch I have a couple of blocks that are linked to files."


                            Can you show us how these blocks are linked to which files?





                            "Every time I make even a simple change (to) the block"


                            Are you doing RC>Edit Block or what to make the change?




                            Did you try editing the sketch from which the block was made then remaking the block with the same name?