OK, I realize that this might be the stupidest question ever posted on the FOG, but here goes. I've never changed the pad on my ETS 150. Now I'm trying to, but I'm finding it deceptively hard. I know I have to loosen and remove the screw holding the old pad. The problem is that turning the head of the screw simply rotates the pad in the same direction, rather than loosening the screw. Obviously, I need to stop the rotation of the pad, but how do I do that without damaging it?