Mating Mold Spring?

Hi,
I have been attempting to mate a mold spring into a round pocket several times without success. It will easily add a coincident mate between the flat, ground end of the spring and the bottom face of the pocket, but when I attempt to add a concentric mate between the pocket diameter and spring diameter SolidWorks will not allow it. Can any one suggest how it should be done.

Create an axis through the center of your helix and mate that to your pocket. (concentric)

[SolidMartin]

Hi,
You can add a circular cut to the inside of springs in order to make a concentric mate. I am not sure if there is any other way to mate it concentrically with out doing this. Doesnt have to be through the whole spring, just enough to select for the mate.
Or create an axis in the spring model and then use that for mating in the assembly. It's easy to hide and doesn't alter the spring model.

[tilco]

The spring has already an axis. You can show this by the pulldown menu "View" and put on axis and/or temporary axis.