I'm trying to model an impeller stage.  My work thusfar is attached as Impeller_Hub.sldprt.  I have an example which I am trying to replicate the general features of, attached as Example_Impeller.sldprt.  The main stumbling point is making the fillets around the impeller blades as they attach to the hub.  Specifically, I'm running to errors like "Laminar edges cannot be filleted", which as far as I can tell means that I need to knit the surface first, but then I run into errors trying to do that.  And so on.  I used the blade edges as guide curves when creating the hub, so I would think they would be coincident, but I'm not sure why I'm unable to create a fillet.

I suspect that the problems I'm running into are the result of poor design choices made earlier in the model.  For example, I wasn't able to make a solid loft for the hub initially; I had to create a lofted surface and then a solid loft with merge bodies unchecked.  This is my first foray into using SolidWorks, so I'm sure I'm making some pretty obvious mistakes, but any advice anyone has would be greatly appreciated.

Also looming in the near future are the fillets that would be attached to the shell.  In the example file, this appears to be done by creating a thin solid body parallel to the outer edge of the blade and filleting from that to a surface that is coincident to the surfaces of the blade itself.  Is that... feasible? 

Thank you for reading!