13 Replies Latest reply on Apr 23, 2012 9:00 PM by Jerry Steiger

    Create a path to extrude ...

    Altibano Ortenzi

      Hi,

       

      Could anyone help me with this problem?

       

      I need to create an extrusion but the profile doesn't a circle. Rather, it is an irregular geometry quite similar to an ellipse but without the both radii. I mean, There are at least five centers on geometry. I couldn't correlate the paths with the geometry. Any help?  Thanks.

        • Re: Create a path to extrude ...
          Anna Wood

          Post your file of what you have tried so far.  Used the Advanced Editor link in the upper right of the dialog box to attach your file.

           

          Cheers,

           

          Anna

            • Re: Create a path to extrude ...
              Altibano Ortenzi

              Mast01.jpgThank you Anna and Scott.

              It's actually a mast profile longher 12000 mm. It is conic along the length. This would not have a problem. The problem is extruding an oval or elliptical profile in a helix and conical at the same time. As would establish the pitch, because the profile is not circular.

                • Re: Create a path to extrude ...
                  Scott McFadden

                  Altibano,

                  It looks like you need to create a lofted feature.

                  Create your profile shapes on different planes at different distance locations.

                  Then I would use the fit spline command to make all the shapes one entity.

                  This make the loft blend easier.  The create a sketch on a plane that runs through

                  all of the profile sketches and use the pierce constraint to attach the guide curve

                  to the profile sketches.  You might need to create more then one guide curve sketch

                  depending on how complex your outside contour is.

                  For additional help it might be worth while to go to youtube and look at creating loft

                  training videos.

                  Hope this helps you and good luck.

                    • Re: Create a path to extrude ...
                      Altibano Ortenzi

                      Scott, I didn't understood the last part (is pierce constraint a command or relation?) and I couldn't find how to connect three or four guide lines with 3 or 4 different radii to create an unique curve through the profile, with the pitch I need. For simplification I've tried to create a pitch curve along a elliptical profile through the loft extrusion without the conical variation, but without good result. Anyway I'll look for it in other sites. Thanks.

                    • Re: Create a path to extrude ...
                      Altibano Ortenzi

                      PipeDeform.pngSorry all. My mistake... this elliptical geometry is formed by 'n' rectangulars as the same as steel cables, but they form a skin over all surface of profile. There are filaments of fibers like as stripes and are disposed to forming an helical. Next in oposite side the same rectangles must be extruded with a gap between them. I've attached another file... The image above was a circular profile with ten extruded rectangles for each direction +/- theta.

                        • Re: Create a path to extrude ...
                          Jeremy Feist

                          here is a quick example using SW 2011

                            • Re: Create a path to extrude ...
                              Altibano Ortenzi

                              Thanks Jeremy Feist Is just this procedure that I need.

                               

                              Thanks also to Scott and Anna by your first contribution.

                                • Re: Create a path to extrude ...
                                  Erik Bilello

                                  Altibano,

                                   

                                  Just for fun, here's another method to get a "helical" path on a tapered ellipse.  It will only work if your profile is a true ellipse though.  I think the method could be used for other tapered profiles if you can create an appropriate "spiral" shape to project on to the tapered surface, perhaps using an equation driven curve.  I'm also presuming that you are not needing the strands to be woven, that would require a different method to get your path(s).

                                    • Re: Create a path to extrude ...
                                      Altibano Ortenzi

                                      Thanks dears,

                                       

                                      Actually the cross section is a NACA profile used for rigging, rudders and keels of boats (aireplane wings too). I design with RHINO and ORCA3D but I cannot import the file to use as sketch on SW. So I must start from zero. I think the part that Jeremy sent could be the best way. In next days I'll try to finish one profile and I'll post here the result.

                                       

                                      Erik I'll take you drawing too and I'll use it to compare the both methods. Thanks a lot for all.

                                      See you.

                                        • Re: Create a path to extrude ...
                                          Erik Bilello

                                          Altibano,

                                           

                                          I expected as much when you referred to a mast.  I played around with producing an "elliptical spiral" that was bigger on one end than the other and I'm sorry to report that I have been quite unsuccessful.  It sounds like you probably know the geometry of your profile enough that developing a "spiral" might not be too hard.  You might look into using the "Curve through XYZ points" either to generate a "spiral" even the complete "helix".  It is surprisingly easy to generate a large set of X,Y and Z values with a spreadsheet (autofill is your friend) and importing large data sets are quite easy on (computer) resources.  Getting your profile to stay put on a large path with a lot of revolutions may be your real challenge.  I've found that for me after a hundred or so turns any profile but a circle starts to do funny things. I hope you can post your results for us.

                                           

                                          Good luck.

                                          Erik,

                                  • Re: Create a path to extrude ...
                                    Jerry Steiger

                                    Altibano,

                                     

                                    I don't have time to look at the other solutions you have been given, nor time to make an example for you. You might want to search in the forums on how to make coil springs that do not use a round major diameter. Examples include elliptical springs and rectangular (with rounded corners) springs. The concept is that you make a helical surface and an extruded surface which matches the center line of your wire. The intersection curve between the two surfaces is the sweep path for the wire.

                                     

                                    In your case, the helical surface establishes the angle of your wraps. The airfoil shaped extrusion would be tapered, either by an extrusion with draft or by a sweep or a loft. You would need offset airfoil sizes for each layer of your mast.

                                     

                                    Jerry Steiger

                              • Re: Create a path to extrude ...
                                Scott McFadden

                                Altibano,

                                Welcome to the forum.

                                Like Anna said can you post your model or if nothing else some images that show

                                exactly what you are talking about?