AutoCAD Inventor :: Model Cut Produced By Ball End Mill Taking Arbitrary 3D Path

I've been trying to model cut produced by a ball end mill taking an arbitrary 3D path.  I know how to do this for 2D paths (and this has been discussed a couple of times on this forum), but I have had little to no success extending this to paths in 3D.  I've attached an Inventor file that demonstrates what I want to do, it has an sketch that describes the tip of the end mill and the path that I want the center of the tip to trace out.

This seems like something that should be possible using sweep feature, but if it is then I have not found a way to get this to work.  The issue is that I have not been able to effectively control the angle of the sweep plane with respect to the path.  In reality, the normal of the plane should be equal to the tangent of the path with the z-component zeroed out.

However, if I sweep using the path and the "Path orientation" then it does not zero out the z-component, if I sweep using the path and the "Parallel orientation" it does not take the x&y tangent components, if I sweep using a guide rail or guide surfaces it also does not zero out the z-component.

In fact, the only way I could come up with to accomplish this would be to sweep the path in 2D and then to use a series of bend part features in order to put things into 3D.  So far as I can tell this works, but back calculating the 2D curve is so backwards and laborious that I can't imagine using this for anything. In Solidworks this is relatively easy using the sweep solid feature .