To make my situation simple, I have two sub-assemblies in an assembly. Both sub-assemblies have several sketches and I want to mate a reference axis fixed to the center of a cylinder in a sub-assembly to a point fixed to the center of a disk in another sub-assembly. I want to fix the direction of the cylinder exactly to the center point of the disk.

Unfortunately, I tried to mate those two sketches in the assembly but didn't go well. I could open the mate window, select those two sketches, check coincident and hit check mark but happened nothing...

What was wrong with these ways? OR Is there any good way to accomplish what I want?

I'm working on SOLIDWORKS 2011 SP4.0.

Thank you in advance.