In Frame Generator, several commands are available for modifying frame members and applying end treatments. End treatments are accumulative, and can be mixed. For example, you can apply miters or mixed end treatments to three frame members that meet to form a corner.
You can also cut treatments on curved or merged members. End treatments of an arc curved frame are trimmed following the curve shape. End treatments of a spline curved frame are trimmed through tangent direction. However, Miter does not support two curved or merged beams. Curved or merged beams cannot be trimmed by or extend to a curved surface. Only Notch supports Elliptical beams.
You can sketch a notch profile together with the base profile, and extrude the base profile. Next, convert it to an iPart, select the notch profile when authoring the iPart, and publish it to Content Center. Then you can apply the notch to cut another frame during the Notch process.