"here are two possibilities to transfer this vertical movement to the rudder tab. These parts are below the articulated screw that detaches rudder rotation from windvane rotation while allow push-pull vertical forces.
The first idea is the same as…"
"sorry the image is so big, I halfed it but still big..
Now follows the bottom of the vertical shaft, just an idea about how vertical movement allowing horisontal rotation of the part that gets attached to the rudder. It needs to be exactly above…"
"here-s a take on understanding horizontal axis wind vane pilot. There-s the yellow wing, its vertical push-pull crank system, fixed to a rotating drum ( this one should be rotated 360 deg by an actuator to change sail direction), a (whitish) holding…"
"Regarding foam cutting, you can source the nichrome wire on ebay http://www.ebay.com/bhp/foam-cutting-wire
I've seen some are using guitar strings instead of nichrome.
When I built mine I found harder to source a 300watts transformer, that…"
"regarding the question you asked on http://engineering.stackexchange.com
The simplest self-locking rotating actuator is one that uses a worm gear, like windshield wiper motor does. If that is too strong for rotating only the wind vane mast,…"
"Regarding Ceconite - it in itself is woven polyester. Of course UV can degrade it and water pass through if it werent a resin (or dope) and paint applied to it. The resin seals it and the paint protects agains UV. The polyester fabric itself…"
"Yesterday I headed to the coast to find some boats with wind-vanes and to find somewhere to build a boat.
No luck with finding wind-vanes, but I may have found two places to build a boat. And topped-up my sun tan :)
I have a couple of hours free…"
"whatever method is used to rotate the rudder (or windvane) there is still needed a method to read its actual position.
One method is to have the encoder on the motor shaft (or the screw shaft like they use on tiller-pilots), and…"