So I have done quite a few realistic compression springs in SW.  They arent perfect but pretty good.  Now Im trying to do a torsion spring.  Sort of whats in a caulking gun handle.  basically 2 coils with 2 long legs. 

so i found a way to make it work "in the sketch"   I drew  a helix, then the leg, then attached the leg and the helix with a 3 point arc.   As long as you stay in the sketch everything moves like it should (the arc "stretches" and everything. but  once you close the sketch and the sweep rebuilds, it wont move. (which i normal for solidworks parts)

I dont think building an assembly like i do for the realistic compression springs would work very well either.

anyone have any ideas? maybe im approaching this the wrong way.    Basically, I need to somehow (via assembly mates)  control the location of the leg end point, which modifies the sketch on the fly.  

Unless there is some much better way of doing this.  I cant think of one.

this is the part im dealing with. I control it now with configurations.