It is not possible in QCad. There are several other operations which are also not possible with splines or ellipses in QCad, including trimming to them. QCad appears to be unable to determine the exact coordinates for arbitrary points on these entities. You can snap to an endpoint or a midpoint of an ellipse, but you can not trim to an arbitrary intersection with an ellipse or a spline. This same limitation affects hatching, since hatching requires trimming. -- Carl Brown Whitefield, NH USA