Solid sweep cut, odd result, what am I doing wrong?

Hello, I'm trying to do model kind of an odd cut over a hole where it breaks into a bore.

At the end of the path, the sphere (solid body) is tangent to the bore which should give you an idea of the intended cut.

If something looks funny, I can typically figure out where I screwed up, but I'm absolutely clueless on how this result happened.

Any ideas on why the cut looks like that and on how I can fix it? I don't remember having done a solid sweep cut before, so hopefully I'm just screwing something simple up.

solid body and path:

confusing solid sweep cut result:

Thanks!

Blake