Hebridean Wind vane Design
Usually, "horizontal" wind vanes deflect on an axis around 20 degrees from the horizon (variable in some cases) which is why they "feather" into wind. The extent of this deflection creating course correction is therefore limited depending on the degree the boat is off course (whatever the wind strength!) but prevents over-steering the boat.
The Hebridean is different. The vane deflects on a horizontal axis (0 degrees from the horizon and only "feathers" when the pendulum blade swings rotating the vane axis (about the vertical) into wind. Only then is the vane damped to prevent over-steering. Until then, vane deflection is not "limited".
This "feed-back" mechanism is the unique feature of the Hebridean. It results in rapid response when the boat drifts off course, without sacrificing control - particularly necessary when running down wind in heavy seas.
Simplicity of construction and maintenance is also a key feature of this design, requiring little more than basic wood-work skills and tools to complete.