cyclic animation

Well, not really animation, but dupliframe modelling that uses Ipo curves. I was trying to figure out how to do the telephone cord example posted by GrayBeard I tried creating a surface circle, parent it to a nurb circle then parent the nurb circle to a path. That way the surface circle would move along the nurb circle while the nurb circle moves along the path and hopefully generate the coils in the process through dupliframes. But the surface circle only goes around once, then stops moving while it’s parent the nurb circle completes its way to the end of the path, so only one coil is generated. I’m very new to Blender, only had it for a month, so I’m a little lost here. How should I set up the Ipo so that the surface circle keeps moving to the very end? Or is there a tutorial for doing this one? Think of it as the moon orbiting the earth while the earth goes around the sun. Only my “moon” only goes around once, then stops moving while it hitches a ride on the earth for the rest of the trip.

Browsing the forums and found the answer myself.
Gotta go and try this now. Sorry to take up space.