5 Replies Latest reply on Nov 14, 2009 4:03 PM by 1-FG9OMX

    Top-down assembly and in-place mates

    1-FG9OMX Nov 13, 2009 2:31 AM

      I'm somewhat new to top-down; pardon my question if indeed it's a simple solution "I should already know..."

       

      I've created three round parts - all concentric to one vertical centerline. I want these parts to rotate about this centerline axis - however, due to my building the model the way I have, the parts are fixed into their respective positions.  In other words, I cannot get the parts to rotate freely about this common centerline axis nor will they "pull apart" up and down (along) this centerline.

       

      Is there a means by which I can break the in-place mates - and re-establish new mate relations so as to allow these parts to rotate independantly of one another?

       

      Thanks in advance for any advice/corrective action anyone can render!

        • Re: Top-down assembly and in-place mates
          Deepak Gupta
          Deepak Gupta Nov 13, 2009 2:37 AM (in response to 1-FG9OMX)

          You can break the in place mate but that can disturb the references. The way out can to delete the in place mate and reset the references so that parts doesn't have any relations with each other and no references from assembly. And finally re mate as required.

           

          Other way will to create them separately and mate in assembly.

            • Re: Top-down assembly and in-place mates
              1-FG9OMX Nov 13, 2009 6:38 PM (in response to Deepak Gupta)

              Hello Deepak, thanks for your suggestions.

               

              Prior to posting my question, I indeed tried to break the in-place mates - so as to reassign the desired mates to these parts. However, SW would have none of it.  It was as if SW would not let go of the in-place (original) mate assignments.  I'd delete the mate - with the intent of leaving it blank (no mate) - and by some default action, SW put the original (in-place) mate back into the part...

               

              I think my fall-back is to make 3 re-named copies of this assembly, and delete respective parts out of each file so as to create three individual parts, and bring them into a new assembly. This was an alternative suggestion form you too I believe, right?

               

              Thanks,

              MP

                • Re: Top-down assembly and in-place mates
                  Rudy Lyon
                  Rudy Lyon Nov 14, 2009 9:31 AM (in response to 1-FG9OMX)

                  We do quite a few axi-symetric assemblies and the process that works well for us in a top-down assy is to;

                   

                  1. Create all revolved sections on same plane adding design intent and contraints between sketches from different parts. Note that the only assembly mate at this stage is the in-place mate that's created when the new part is created in-context within the assembly.
                  2. Once the design is completed we open the part and delete all in context dimensions or contraints on the sketch created in the assembly. At the same time the sketch needs to be re-constrained to replace the deleted in-context items.
                  3. Go back to the assembly and delete the in-place mate that created the part in context of the assembly.
                  4. Create your assembly mates for the parts and your assembly will function as you would like.

                   

                  One other thing that we have learned is to use hide solid bodies while working in the assembly with sketches to make selections and visualization of the axi-symetric revolve sketch easier to work with.

                   

                  Hope this helps.

                    • Re: Top-down assembly and in-place mates
                      1-FG9OMX Nov 14, 2009 4:03 PM (in response to Rudy Lyon)

                      Thank you Rudy - I like the method you've described.

                       

                      I didn't read your reply until AFTER I created three copies of the assembly - deleting the unwanted parts on each copied assembly, until I had three individual parts. Then I imported them into a new assembly, adding the desired mates as I went along.

                       

                      That's a lot of drama for three simple parts on a common axis!

                       

                      Deepak's solution was nice too - credit where credit is deserved.  Your method, however, seems the best for avoiding this sitch in the future.

                       

                      Thanks again. Best regards...

                        • Re: Top-down assembly and in-place mates
                          Mauricio Martinez-Saez
                          Mauricio Martinez-Saez Nov 14, 2009 5:18 PM (in response to 1-FG9OMX)

                          Michael,

                           

                          The Top-Down modeling of three simple parts (or any nnumber of parts) having free movement along a single axis as well as free rotation among that axis, do not require all that "drama".  It is very simple...

                           

                          The attached Zip File contain a simple assembly with three parts modeled 100% Top-down and being 100% parametric (change any dimension inside the two sketches placed at the top assembly level and that will drive any part dimension), which you can rotate and move along the axis (infinite movement).

                           

                          Open the assembly and take a look on how it is done, fast and simple (the attached example was done in less that 10 minutes).

                           

                          Top-Down parts with free axial and radial movement.JPG