Given a path (bézier curve) and a circle (black dot) as it follows
I'd like to extrude the circle along the curve such as it creates the following surface
Using the bevel tool with blender, this is the best I can get. (Add>Curve>Bezier, Add>Curve>Circle, Bezier curve>Data>Geometry>Bevel, Rotate the circle in edit mode)
I expect the edges to be smooth. Somehow this person made it happen by mistake. But I can't figure how he did. Do you know how to fix that ? Thanks !