Sounds like a great project
. Keen to hear why you prefer a vertical axis over a horizontal? but anyway for what it's worth I have used plywood
vertical axis vanes. The Fabric
one was a Sayes rig. It had two Tee section posts with a "v" shaped vane made from a heavy fabric sail lashed to the ends of the Tee's.
It worked reasonably well, and certainly seemed to have more power than the standard flat plywood ones I had used before on simple trim tab systems. The sail needed to be very tightly lashed in place.
The best course setting system I have used was a worm drive system much like the Hasler.
This made it easy to adjust while the vane steered. The simpler and more common two disks and a pin in holes clutch
is a right royal nuisance at times, because as soon as you pull the pin out the vane cant steer the boat
, and it is hard to get it back in at exactly the right spot, Though I have heard of some cunning ways to deal with this using two pins and elongated holes or somesuch...
I bent a vertical axis vane shaft once in a knockdown. It was 2 inch stainless tube as I recall
. So they either need to be very strong, or have a weak fuse, like the nylon cover, or it's lashings, that can break to reduce the load on the important bits. The same wave ripped the trim tab off the rudder
, we think the trim tab flexed enough to pop out of the bottom bearing.
For my old horizontal axis Flemming I made a light plywood vane with big cutouts and sewed a very light nylon cover for light airs, I could pull it off in over 20 knots and just use the plywood part, maybe something like this could work
for you as a reefable sail?
Very keen to hear what you come up with, got to build something for the new boat
sometime. All the best with it.