Assembly says concentric mate is overdefining.. but how is it possible?

Hello everyone,

     Can you guys help me with my assembly?  For some reason I can't get a concentric mate going between the 2 threaded rods.  There seems to be enough freedom of movement and the planes seem lined up and parallel etc.   I've run into this numerous times before and can't figure it out.   Even being extra careful in all of my mates from the begining.  Any advice is greatly appreciated.

SolidworksAssemblies