6 Replies Latest reply on Oct 31, 2011 11:40 AM by Robert Brookover

    Attempting to model ladle from "Solidworks Surfacing & Complex Shape Modeling Bible" - issue w/ "thicken" command

    Robert Brookover

      Hi,

       

      So I have Matt Lombard's "Solidworks Surfacing & Complex Shape Modeling Bible" and I'm working on the Ladle from Chapter 15. 

       

      I've brought in the 2 sketch pictures, made the projected curve, and even lofted the surface. 

       

      I'm now at the point of wanting to "thicken" the bowl area of the ladle (p. 284-285 for those who have the book).  According to Matt, he used the "thicken" command & thickened it to the outside 0.1." 

       

      I'm at a loss, for no matter what I do, I cannot get this to work.  Depending on the options I choose in the "Thicken" command (or in the command previous to that, which is the "Surface Knit" command, I end up getting 1 or both of the following "Rebuild Errors":

       

      Failed to offset or face could not be deleted.

       

      Unable to thicken the surface.

       

      If someone could please explain what these errors mean, and maybe take a look at my file & see what I need to change, that would help me out a lot.

       

      Thanks,

      Rob

        • Re: Attempting to model ladle from "Solidworks Surfacing & Complex Shape Modeling Bible" - issue w/ "thicken" command
          Matt Lombard

          Robert,

           

          I've had some problems with that part. SolidWorks seems to have changed something significant since 2008. My 2008 models do not rebuild in 2012.or 2010 for that matter. It loses a curve in the definition although the curve is listed under it as a parent.

           

          Anyway, attached is a model that works for 2010. Not sure what version you're using.

           

          Notice that if you suppress the trim in your model and try to thicken to the inside or the outside, portions of the handle start to curl around on itself. On your part for some reason, if you edit the loft feature, notice that the lines that go from the center to the outside are angled pretty heavily. To solve this, I added some connectors and made them more perpendicular to the Right plane. Anyway, you can use connectors to straighten out the loft, prevent the surface from getting nasty curvature, and allow it to thicken.

            • Re: Attempting to model ladle from "Solidworks Surfacing & Complex Shape Modeling Bible" - issue w/ "thicken" command
              Alin Vargatu

              Robert and Matt, Just using Robert's file, without any other modification, it looks like SW has a problem thickening the degenerate surface.

              Trimming the tip to add a short edge allows the thicken to work (see picture)

               

              degenerate surface.jpg

               

              Updated: Just ignore what I said above -> A closer zoom to the tip shows the curling in the surface:

               

              Curling.jpg

              • Re: Attempting to model ladle from "Solidworks Surfacing & Complex Shape Modeling Bible" - issue w/ "thicken" command
                Robert Brookover

                Matt,

                 

                Thank you for responding.  First, let me say that I really enjoy your books, as they are more "real life" than the "step-by-step, click-this button" type of tutorials. 

                 

                So I will look at the file you sent, but I'm still confused as to what those errors were I was getting, and why my file wouldn't work?

                 

                Also, once I look at your file, and if I can replicate it myself, should I let my instructor know about the "new" file you sent, so that he can distribute it to the other students?  Are you planning on updating the other files used in the book to the latest version of Solidworks?

                 

                BTW, in response to you wondering what version of Solidworks I'm using, it's the  the "Student Edition, Academic Year 2011-2012" (which, if I recall, the student edition is the last year's edition, which is 2011). 

                 

                P.S.  No offense, but I believe your book, as well as my instructor, as well as most other surfacing tutorials I've read, all talk about using the minimal amont of connectors to make a spline - but you're saying that I should add connectors to "straighten out the loft, prevent the surface from getting nasty curvature, and allow it to thicken."??

                 

                So, how would one know how many connectors are needed versus using too many?  Is there a general rule of thumb to follow?

                 

                Anyway, thank you for your information.

                Rob

                 

                UPDATE:  So I reviewed Matt's model, and I tiled it vertically w/ my model, and just tried to replicate his spline's the best I could.  Attached is the result - IT WORKED!!  I was able to thicken it!!!

                 

                I'm very appreciative of the help I received which allowed me to surpass this obstacle, but I'm still confused as to why my original model didn't work but this one did - I guess what I'm saying is - I don't know what I did wrong in the first file, or did "right" in the 2nd file, so I'm not sure I'd be able to replicate this in "real life?"

                 

                At any rate, thanks for the assistance!

                Rob

                  • Re: Attempting to model ladle from "Solidworks Surfacing & Complex Shape Modeling Bible" - issue w/ "thicken" command
                    Matt Lombard

                    Robert,

                     

                    About connectors, they are not the points within a spline, they are kind of ad hoc guide curves you can add in Loft and Boundary. If you right click on the edge of a loft feature while editing the loft, and make sure the Selection Manager is not active, one of the RMB menu choices is Add Connector. This is a series of dots that touch each profile in one direction. you can slide the dots back and forth and make the UV mesh behave better. When the UV mesh starts to collapse on itself, when the angle between U and V becomes less than say 60 deg, it can leave artifacts on the model, and can cause the model to self-intersect in ways that aren't obvious. The curling you saw was one of those ways.

                     

                    In order to really understand this stuff, you would need to work with it a lot to have an intuitive grasp, or be a mathematician to understand exactly why stuff happens the way it does. The book tries to convey an intuitive grasp. Thinking of the UV mesh as a loosely woven fabric that can wrinkle and stretch a little is probably the best analogy I've seen. The two different directions of threads within the weave represent the U and V directions, and making them less perpendicular to one another requires you to stress the fabric a lot.

                     

                    Feel free to give the new file to your instructor.