UGH. Sorry for posting. I figured out the top circle needs to be filled using Planar in order for it to work.
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This video shows me trying to blend but with little luck: It keeps saying "Calculation Failed."

http://youtu.be/Sa7EFH-j3cs



Here's the file: https://altuit.cloud/web/dbpub/3D/blendissue.3dm

No problem Chipp - yes if you want to construct a surface blend you need to select all edges for that, not just some edges and some regular curve objects. Basically surface blends always match themselves to the surface shape and so you need to construct a surface there for it to know how to shape it.

- Michael

Also another thing that can be a bit tricky with blends is if you have a separate cutting curve object sitting right on top of the surface edge. In a case like that with both the curve and the edge stacked on top of each other the curve will get precedence if you click on it and to make the blend you need the edge selected instead.If you run into that you need to hide or delete the curve so that you can target the edge that's directly underneath it better.

- Michael

Just extrude you upper circle without caps!
Then the 2 circles will be blended! ;)
Each figure must have a "surface" for be blended!