11 Replies Latest reply on Mar 5, 2013 9:21 AM by Charles Culp

    Need help with surface

    Jens Leander

      Hey Guys

       

      I am an machine engeneering stud from denmark, I am trying to learn something more about surfacing in solidworks. But now I am facing a problem with a "hobby" projekt i am doing, just for fun.

       

      I really hope someone can help me on this. Not just finishing my model, but also teaching me something.

      I have modelled this, it is a seet for a chair. But i am pretty much struggeling with adding something underneath it for mounting a chair leg.

       

      I can easily add something which look awful, but I need to blend it perfectly and tangent into the curves of the chair. I thought about something as simple as a hole, but i need to extrude something to do that hole in.

       

      I have attached my solidworks file. 

       

      Let me know if i am not clear enough

       

       

      / Jens

       

      Sorry for bad english.

        • Re: Need help with surface
          Louis Liu

          hello,it's my pleasure to talk about this problem with you,do you want to add some leg undereath the seat?or something you want to

          do,i just done't understand completely.

          i am an chinese engineer,my english is not so good,hope you understand!but i believe that we can resolve this problem,isn't it?

            • Re: Need help with surface
              Jens Leander

              Hey Louis thank you for your help :) Yes I want to add a leg, but first of all I want to add something underneath my chair seat part to add the leg into.

               

              You know, some kind of hole for a round chair leg.

                • Re: Need help with surface
                  Louis Liu

                  Jens and Charles,

                   

                  i really admire the way which Charles Culp has done in file Chair_v2.sldprt.as James said,the seat has to be cut a little bit extra material

                  which is sticking through on the seat of chair.my opinion is that Chair_v2.sldprt has no problem,but the feature for the boundray extrude is no necessary to be  done by solid feature.i would like to do the boundray extrude with surfaces(if i were),and knit them to a whole solide part .in this way,you might not  worry about if there are some extra material out there.anyway,i don't really think it is suit for you.

                • Re: Need help with surface
                  Jens Leander

                  Chair two.png

                   

                   

                  Hello again i have drawn something in paint to illustrate what i am looking for:

                    • Re: Need help with surface
                      Charles Culp

                      Jens,

                       

                      I have a newer version of SolidWorks than you, so you might not be able to open this file. I have attached it anyway. Finish the sketch in Sketch 7 by mirroring it to create a complete enclosed sketch. Then extrude up, with an End Condition of "Up to Body". Then select the chair as the body to terminate the extrude.

                       

                      Now you can use the Fillet command to create a fillet around the base. There is an additional option for Curvature Continuous in the fillet, and I would prefer to keep this on. Unfortunately, the shape of the seat bottom does not allow for a large fillet with this option turned on. Consider deleting these faces, and replacing with a boundary surface, with end conditions of curvature continuous.

                       

                      Stool-Transition.PNG

                        • Re: Need help with surface
                          Jens Leander

                          Thank you so much for that Charles Culp. It was a very nice and SIMPLE way to solve this. I will mark your post as correct.

                           

                          But.. I am still looking for some other ways of doing this, maybe something a bit more advanced with some surfaces or something which I can learn from

                           

                          Thank you again Charles

                            • Re: Need help with surface
                              Charles Culp

                              Sure. Instead of extending the extrude "up to body", do it a fixed distance, about 90 mm from the seat bottom (I used 200mm).

                               

                              Then, create a sketch on the Top Plane that is the shape you want to be your split line on the seat bottom. Then use split line to create this on the seat bottom (see image below).

                               

                              Stol_SplitLineSeatBottom.PNG

                               

                              Now you can use Boundary Boss/Base to create a nice, smooth, and fully curvature continous transition between the two.

                               

                              Stol_BoundaryBossCurvatureToFace.PNG

                               

                              Except this gives an error!

                               

                              Stol_BoundaryBossError.PNG

                               

                              So now we must use surfacing tools. Delete Face to each section.

                               

                              Stol_DeleteFace.PNG

                               

                              Then use Surface>Boundary Surface

                              Stol_BoundarySurface.PNG

                               

                              And finally Surface>Knit to create it back to a solid.

                               

                              Stol_Surfacing.PNG

                               

                              I have also uploaded this file again.

                                • Re: Need help with surface
                                  Jens Leander

                                  Thansk again Charles.

                                   

                                  Your last post really gave me something I was playing around with the first thing you did (boundary boss/bass). I changed some of the sketches and then i had this:

                                   

                                  Chair_v2.3.PNG

                                   

                                  But when taking a closer look at the other side i explored this:

                                   

                                  Chair_v2.1.PNG

                                   

                                  Marked with blue:

                                   

                                  Chair_v2.4.PNG

                                   

                                  How would you get rid of that thing?:)

                                   

                                  I have attached the SW file

                                   

                                  And last thing; in your last post you figured it all out with surfaces. But how do you "fill" up so it will not just be a shell anymore but a solid?

                                   

                                  I really appreciate your help thank you!

                                    • Re: Need help with surface
                                      James Moynagh

                                      Jens,

                                       

                                      If you look at Charles model he has delete face action after the extrusion for the stand part, that is how he got it back to a surface, you missed out that part, so the should get rid of that extra material which is sticking through on the seat of chair.

                                      • Re: Need help with surface
                                        Charles Culp

                                        Yes, sorry, I never responded. The area above the seat is caused because you used solid boundary, instead of surface boundary. I suggest using surface boundary, then you won't have this problem.

                                         

                                        The way to convert surfaces to solid is to use the Surfacing>Knit tool. Then check the "make solid" checkbox when you knit all the surfaces together, if they enclose a solid. This is the last image in my above post.

                            • Re: Need help with surface
                              Louis Liu

                              Jens and Charles,

                               

                              i really admire the way which Charles Culp has done in file Chair_v2.sldprt.as James said,the seat has to be cut a little bit extra material

                              which is sticking through on the seat of chair.my opinion is that Chair_v2.sldprt has no problem,but the feature for the boundray extrude is no necessary to be  done by solid feature.i would like to do the boundray extrude with surfaces(if i were),and knit them to a whole solide part .in this way,you might not  worry about if there are some extra material out there.anyway,i don't really think it is suit for you.