11 Replies Latest reply on Jun 25, 2009 4:33 PM by 1-GCUQMA

    Kniting

      When kniting two surfaces together that are not perfect, how much will SolidWorks change a part to force the Knit.

      And when you check "Minimal adjustment" hou much will it change the part to try and complete the knit
        • Kniting
          Matt Lombard
          I hope you get an answer to that. SW answer to most stuff is to try to simplify it rather than offering details for better decision making. Simplification usually means a loss of control.
          • Kniting
            Robert Stupplebeen
            In legacy parts (not my mistake) I have seen knitting change 0.100mm thick parts by 0.050mm. Be very careful if the edges do not line up. I would argue that if they do not line up edge to edge you should not knit them together.

            Matt, It would be great to have more control over this and to choose a tolerance where the knit would fail.

            I hope this helps.

            Rob Stupplebeen
            • Kniting
              Michael,

              Minimal Adjustment does not have anything to do with the tolerance that knit users but rather was put in there in 2009 to overcome changing the design intent of your parent features. For instance, pre 2009, if you had split line/s feature on the surfaces that you then knitted, the Knit feature would assume that you wanted them eliminated (made one face), even thou they are split Line features. Now with Minimal adjustment checked, it will not eliminate the split line (or other faces that could be minimized - i.e. eliminated.)
                • Kniting

                   

                  Minimal Adjustment does not have anything to do with the tolerance that knit users

                  Ahhh.... I stand corrected on this. The help file states that this does change the tolerance of what Knit considers. In all practicality thou, it was put in to alleviate the condition I stated before. We are looking into possibly giving the user more control of this in a future version of SW.
                • Kniting
                  Charles Culp
                  Yes. go to: https://www.solidworks.com/sw/support/downloads.htm

                  then log in. then click on "Fixed SPRs". Click to Accept the NDA. Then sign over your firstborn son.

                  Then you can narrow the search results, although the top of the list should be SW2009 SP4.0
                  • Kniting
                    Kevin Quigley
                    Mark, kniting is one of those things that causes issues when moving from system to system. When I used Think Design exporting a solid from that into SolidWorks was nightmare as the stitch/knit tolerances in Think Design could be controlled feature by feature, and when you didi a complex blend, say, the system would automatically apply a very loose tolerance that inside ThinkDesign created a solid but outside it created issues with stitching. It was/is the same for VX as well. In general I find that Parasolid is not so hot with looser tolerances. ACIS tends to be a bit more controlable and forgiving. I've also had Pro/E user moan that the tolerances set in SW exports are too loose for them to use so I presume they have similar issues.

                    In terms of specific examples, in general I can shell and stitch parts better in VX than in SolidWorks simply becuase of the control I have of tolerances. Of course that is only useful if you are machining from VX!

                    In terms of control, it would be good to have the ability to build parts to a specific tolerance, or to try to loosen or tighten the tolerance at export time. Also the tolerance control would be great to be able to set it by a specific value. You can get away with a looser tolerance depending on where the data is going after - and into what system. Some CAM systems are very good at dealing with gaps.

                    I wonder how Inventor tackle this given that it is built ona core of ACIS, and ACIS has specific controls to allow user control of stitching?