I put a great deal of effort and time into designing the rudder/tiller offsets providing full size templets to the builder. I got the “Ackerman” geometry right. The Dragon will complete a tack from broad reach to broad reach. Tacking while hard on the wind never produces a stall. The key was to estimate the turning radius based on other large catamarans I have sailed. Once this is established the individual turning radii of each hull (the rudders are approximately 20’ apart) is drawn and the angular deference between the rudders in a tight turn may be measured. This came in between 7 and 8 degrees. This means the tillers connected to the rudder shafts must be set at a “toe in” angle relative to the mounting position of the Teleflex cable ends of 7 to 8 degrees. If you look at the tillers/connecting link for any beach cat you will note that the tillers are toed in at a slight angle. As the boat is being steered, the inside hull/rudder is making a tighter turn than the outside hull/rudder. Ackerman geometry compensates for this angular difference. This allows both rudders to maximize equally their “bite” in the water and prevent one of them from stalling out.
During the build process, after the rudders and helm steering Teleflex Hub is installed, measurements are made from the Hub to each rudder/tiller location. These measurements were in excess of 20 feet. As the steering station is on the port side of the cockpit the distance to the starboard rudder was greater than to the port side. These cables were ordered from Teleflex to match the measured distances. Cable mounting is literally a snap.
During installation the rudders and wheel are centered. The tillers are given their 7 to 8 degree rotation toward the middle of the boat (Counter Clockwise for Starboard, Clockwise for Port), the ball joint/adjustment is set so the business end of the cable lines up with the attachment hole (11” from center) in the tiller.