I'm giving up on the servo pendulum and fitting a H-vane trim tab instead. Since the rudder has a slight curvature or knee I've been wondering about the shape of the trim tab.
(See Richard's link or my album)
The photo with Badger dried out on the Falklands(?) shows a trim tab solving this problem. Annie mentioned it was done to give more leverage. Are there any calculations involved or did you simply fit a straight trim tab to the rudder? Dijkstera wrote a superb book with all sorts of formula and whathaveyou on designing wind vanes. Unfortunately I hardly understand a word of it!
PS could some kind soul let me know why neither BB code nor the above html work?