A method, apparatus, and article of manufacture provide the ability to conduct a sweep operation in a computer-implemented solid modeling system, A 3D non- planar surface is created. A path for a sweep operation is created. A profile for the sweep operation is created. The 3D surface is selected for use as a guide. An angle between the profile and the 3D non-planar surface is calculated. A sweep operation is conducted wherein a twist of the profile is maintained within a pre-defined range of the angle.
