1 Reply Latest reply on Dec 18, 2008 3:55 PM by 1-GDXXBU

    3d spline curve driven pattern on 3D surfaces.

    John Vard
      Hi all,

      I have a quick question re curve driven pattern in 3D, similar to many posted already on this site, but none of them address the problem of multiple faces. I have a 3D spline that "wraps" around a 3D large solid (but isnt a closed spline, more like a spiral), the solid has multiple faces, overwhich the spline passes. I am trying to pattern an small irregular 3d feature on the large solid, along this spline pattern.

      Everything works, except I cannot get the small feature to be tangent orientated to the spline, i.e if i select "allign to seed" the feature appears patterned and spaced correctly, but oriented wrong. And if I select "tangent to Curve" alignment method, I cannot get the pattern to appear.

      Also, the face normal does not allow me to select multiple faces, or a stitched surface of all the multiple faces. It is critical that my patterned features are normal to the surface where they are positioned.

      My problem is similar to the Help file details on "Face normal (For 3D curves only). Select the face on which the 3D curve lies to create the curve driven pattern" where a pattern of stubs is created on a spline around a cylinder. ( http://www.kxcad.net/SolidWork...D_PATTERN_BY_CURVE.htm ). However my "cylinder" is made up of multiple faces (of a solid body).

      Any ideas or suggestions would be much appreciated

      John (solidworks 2007)
        • 3d spline curve driven pattern on 3D surfaces.
          Here is what I do when I need this sort of patterning on a 3d surface. Usually boolean add/subtract works best here, once you have placed the appropriate bodies. Create the seed body first, and when you do, extrude a block somewhere on the seed body that can be used to orient it (basically you are creating a coordinate system in a moveable reference frame.) For symmetrical seed bodies, I have one face of the block coincident with the symmetry plane.

          Then, using your spline on surface as a guide, open another 3dsketch and place points, dimensioning them how you please. Usually, if the curvature of the spline is fairly consistient, standard linear dimensions will work well. Otherwise, you better get creative. (I don't think we can dimension along splines, can we?)
          Close the sketch, and open a third 3dsketch to begin placing your construction line alignment geometry. Place a line tangent to your spline at each of your points. From there you can create geometry that can be mated to using body move/copy however you wish. The rest is up to you, but here are some pics to show how I have used this strategy. This can be time consuming, but if done right, is very robust and responds to parametric changes quite well.

          Tip: when I move/copy bodies for this purpose, I use the rollback bar alot. I will place the seed body, and then using a new move feature, move it to 2nd position, 3rd, etc, with a new move feature each time. Then, I roll back from the beginning one move at a time and copy each body in it's position before the next move feature is built.