on the rudder and elevator pushrods did you cross the rods. In other words if looking in the radio compartment from the nose of the aircraft does the pushrod on the left side of the compartment exit the fuse in the rear at the right side and vice versa for the other. if not this could be the cause of the binding. Also have you tried moving to the outer most hole on the the control horns and or the inner most holes on the servo control arm? this can limit travel and sometimes reduce or elminate binding if you have a computer radio check the end point adjustment and servo travel. I would suggest solving this mechenacially rather then electronically if at all possible