Hello I am trying to mill a part material on a core side block. But, solidworks doesn't seem to like me extruding cut on this curved surface. I am rather new to solidworks and I didn't know how to project a sketch on the surface so I used the surface spline. Sometimes extruded cut isn't even allowed, sometimes it works but it isn't extruded right. I've tried offset from surface but it doesn't let me click the face I want. Any help would be greatly appreciated.