I am designing a wristband of sorts, and I have a swept boss/base for the basic shape of a wristband.

Next, I projected some sketches onto the surface of the elliptical solid and converted them to 3d sketch entities.

Now I am trying to extrude-cut these shapes on the surface inwards towards the CENTER of the ellipse, but I can only select planes as a directional guide. And making a new plane to guesstimate the proper angle of each and every cut seems silly. Is there an easy way to specify the direction/draft of a cut to be aligned with the origin of an elliptical shape?

Thanks,

Mongol