9 Replies Latest reply on Nov 15, 2017 8:05 PM by Richard K.

    Chamfer edge lost when linear pattern count changed

    Richard K.

      I have a part made up of repeating segments.  After I create the first segment, I use a linear pattern to stack a bunch of them end-to-end.  Finally, I add some features like chamfers and fillets to the outermost ends.

       

      The number of segments is controlled by a global variable.  Unfortunately when I change the variable, the chamfers and fillets break because their associated edges are lost.

       

      Any advice on how to solve this?  e.g. Is there any way I can attach the chamfers / fillets to sketch entities instead of the ephemeral edges?

       

      I know I could totally rejig my design to pattern from the "inside out" "outside in", but that would be a lot of work at this point.  Plus sometimes I need an odd number of segments.

      Also thought about using the linear pattern for just the internal segments then creating a "cap" segment separately (e.g. via mirror or copy/move), but that seems like duplication.  (Also note the features I add to the end segments are not symmetrical).  Final option I considered is not using the built-in chamfer/fillet feature at all and manually recreating them from sketches and extrudes/revolves/etc.

       

      Before I go down this road I thought I'd check if there's a better option.

        • Re: Chamfer edge lost when linear pattern count changed
          Glenn Schroeder

          Couple of things. 

           

          1.  Unless there's some reason why you don't want to, add your fillets, chamfers, etc before the linear pattern.

          2.  When you create the linear pattern, "Features to Pattern" will be selected by default.  From what you described I believe you need to de-select that and choose "Bodies to Pattern" instead.

            • Re: Chamfer edge lost when linear pattern count changed
              Richard K.

              Thanks Glenn.  I'm actually already patterning bodies.  I only want the fillets / chamfers on one of the ends (the one which is "dynamic").  The other end already has features fixed to it so I can't pattern in the other direction.

                • Re: Chamfer edge lost when linear pattern count changed
                  Glenn Schroeder

                  Can you post a Part where you're having this problem?  It's sometimes difficult to understand with just a description.  I'm about to be away from my desk for a while but I'm sure someone will be able to help.

                  • Re: Chamfer edge lost when linear pattern count changed
                    Dan Pihlaja

                    Since you are only putting the chamfers and fillets on the two end pieces, you may want to consider fully modeling both end pieces, then using a linear pattern to create the ones in the middle.

                    You should be able to control the position of the two end pieces with a global variable that is linked to your global variable for the number of segments.

                     

                    Alternatively, you could put the chamfers and radii in as extruded cuts instead (with the positions of the cuts controlled by the same global variable.  Just make sure that you have "all bodies" selected when it asks you which body to apply them to, that way, when the ID's change, it won't affect it.

                     

                    Unfortunately, every time you edit the pattern, the ID of the bodies is changed, which means that the chamfers get broken because the program no longer recognizes them.

                      • Re: Chamfer edge lost when linear pattern count changed
                        Richard K.

                        Thanks Dan, that's the direction I'm attempting as we speak.  Right now I'm working on splitting my "seed" segment in half, mirroring it to the far end, then patterning both ends from the "outside in" before adding the unique end features (chamfers etc).  This creates a whole lot of distinct fragments which I then need to tie together into a single body.  Is there a way to tell Solidworks's "Combine" feature to combine ALL bodies that exist in the model, without having to go and re-select them every time the number of patterned bodies changes?  (If these were features instead of bodies I'd simply select "Merge" in the final pattern).

                         

                        Glenn, I hear you on that comment.  I agree 100% a picture/model is worth 1000 confusing words.  Unfortunately I'm not in a position to post the model at the moment (that might change; I'll share it if so).  If I'm really stumped I'll create a simple demo part to illustrate the problem.

                          • Re: Chamfer edge lost when linear pattern count changed
                            Dan Pihlaja

                            Richard K. wrote:

                             

                            . Is there a way to tell Solidworks's "Combine" feature to combine ALL bodies that exist in the model, without having to go and re-select them every time the number of patterned bodies changes?

                            No, but once you are in the combine command, you can open the solid bodies folder and select the first body, then hold down SHIFT and select the last body, and it will select them all.

                    • Re: Chamfer edge lost when linear pattern count changed
                      Richard K.

                      Thanks Dan.  I appreciate the screenshot, although I'm familiar with what you're talking about.  I was just hoping there might be a way to do it so that I don't have to manually nudge the feature into compiling every time I change the variable.

                       

                      In the end, I wound up doing surgery on my part to remove any patterned edges that need chamfers/fillets and replace them with less ephemeral ones.  It was more work than I wanted, but things are "cleaner" now (at least from Solidwork's perspective, if not mine!). In one case I literally chopped off the pattern-generated end of my part and recreated the exact same geometry to produce an explicit "endcap" sticks around after instance count is changed.  I also managed to turn my patterned bodies into patterned features instead, to avoid the need to combine an unknown number of bodies.  Overall it worked out well, although it left me feeling like I had to go through a lot of trouble to work around things Solidworks could make simpler (I don't understand why they can give us a "Join ALL bodies", or "Join ALL bodies except these" construct).

                       

                      I appreciate you guys responding to my thread so quickly!

                        • Re: Chamfer edge lost when linear pattern count changed
                          Dan Pihlaja

                          You know...I was thinking....

                           

                          Since you are creating a pattern of features that are all end to end.....what if you modeled the entire thing as 1 unit and have the length controlled by the global variable....

                           

                          Then add a cut feature and then pattern the cut feature instead.   This should keep your chamfers intact, especially if you put them in before the cut feature.

                           

                          I played with a few things and I am not totally sure how it would work.....but maybe it will put a bug in your ear.