Wind vanes refinedOct 24, 2013
Newest developments in wind vane self-steering technology
(page 3 of 4)
Trim tab auxiliary rudders
Imagine a trim tab auxiliary rudder dutifully steering a 35-foot vessel while its airvane is mounted at the top and off to one side of a solar panel arch. Scanmar’s Auto-Helm has always been capable of such unorthodox installation, yet skippers are getting more creative at pushing the envelope in finding places to mount the airvane.
As long as the connecting cables, similar to bicycle brake cables, are not kinked between the upper and lower units, you can install the airvane mast literally anywhere there is uninterrupted wind current to the airvane.
Scanmar appears to be the sole survivor of all the trim tab builders that have come and gone over the years, more than likely because of its uniquely adaptable installation. There are plenty of online designs for building your own trim tab and auxiliary rudder, but you would be far better off taking all that time and money spent on machining and refining your self-steerer and investing it in a more redeeming pastime — like ocean voyaging!
Bernwall will be the first to tell you: if you think your vessel really needs an Auto-Helm, he will be more than happy to sell you one, but he will still recommend the Monitor first. Remember, while a trim tab feathers more delicately while sailing downwind in light airs, in rougher conditions it does little more than offer some stationary lateral resistance to prevent yaw. The servo-pendulum, on the other hand, actively repels side-sliding, keeping your boat in the groove while surfing down the faces of huge waves.