Bending around a curve at a point

In the attached file I have an elliptical curve and a closed polysrf.
I would like to “bend” the polysrf along the curve so that there are equal amounts on either side of the point shown.

I have tried the Bend command but it seems to only want to bend around one end. I’ve tried splitting the polysrf in half, chopping up the curve but I have had no success. Is there any way to do a bend like this?

Problem Bend.3dm (3.3 MB)

Seems like you can simply use “Flow along curve” and use a straight line as a base curve, then use your existing elliptical curve as the target. That will “bend” the entire part.

However, if your goal is to extend only the end surface so that it takes the shape of the curve, then you can do that with the “Move face to a boundary” command. First, you have to extrude the curve in the same direction as the end surface of the solid model (the most convenient way to do that is to temporarily set the CPlane along the surface you want to modify with “’_CPlane _Object”). Then, run “Move face to a boundary” and select the face you want to modify (I coloured it in yellow), then select the extruded surface (coloured in blue).

An alternative way is to move that face further, by holding simultaneously Crt+Shift (or use “Move face” with “DirectionConstraint=Normal” from the command line) and drag the end surface with the Gumball until it moves enough to overtake the extruded surface that I mentioned above. Then run “Boolean difference” and use the extruded surface as an input. For this particular case you don’t need to do anything else, but if the extruded surface had opposite direction you can swap it either with “! _Dir”, “! _Flip” ор “! _ShowDir”.


Thanks for the help. It looks like I need to expand my problem.

I am trying join these pieces to a curved surface that I created using a sweep that follows the same curve. Unfortunately, I am getting lots of nonmanifold edges (which is why I was trying to avoid in the first place) and total failures (split/joint in these cases creates nonmanifold edges).

I see there is a flow around surface command but, from the documentation, I am not sure that looks like it would solve this problem.

Do the flanges with the holes need to be bent? If not then position the objects which will be flowed so that the extend slightly beyond the base curve/surface. Then flow the objects with

flow along the curve or surface using the Rigid=Yes. Then Trim and Join the objects to the curved shape or try using BooleanUnion.

If the curved object is exactly circular then create one curved object and distribute using ArrayPolar.

Here’s what ended up doing that worked:

  1. Extended the mating surface while retaining reference point for the original object.
  2. Unrolled the surfaces what I wanted to mate.
  3. Laid out the objects on the unrolled surface
  4. Did flow along surface

For cleanliness, I likely would rebuild the bracket using your curve(s) as part of the base.