The end curves are the construction lines, there is no need to create curves between them.


So first you will have:-



On the right is a circle split into 6 sections, on the left, 6 circles trimmed with each other.

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You then select the curves and extrude them






you then need to delete or hide the curves so you can select the edges of the extruded surfaces:



Then blend those surface edges.



Once all done, You can then delete the extrude surfaces as they are not needed.