Rear Charlie Bar backing out

[jaydubya]

My rear swaybar keeps backing out of the clamp. I've repositioned and tightened it twice now. Don't know if there is a torque spec, I'm using TITS principle (tug it tight stupid).

The bar is a hexagonal cross-section and the clamp has the same internal shape and tightens with a socket head cap screw.

I figure I have a few options here - roughen the surfaces of the bar and inside of the clamp, use a shim or apply some lock-tite. Anyone been down this road before?

Thanks.