Self steering airvane

[Chrisc]

I am building myself another self steering gear. In the past I have constructed the air vanes on the horizontal axis 'flip-flop' principle, but for a variety of reasons I wish to build the new vane as the vertical axis weather-cocking type.
These vanes need to be a bit larger than the flip-flop type and I am interested in building it as a frame out of light alloy tube with spinnaker dacron laced within it. Would anyone have any experience or advise in using this type of vane construction as opposed to a plywood vane?
Chris

[gjordan]

You have an H28 with a transom hung rudder. In a week or so I will post some photos of the Quartermaster windvane that was designed for the Folkboat or Contessa 26 with transom hung rudders. It is a simple and inexpensive vane to build. I am going through some old photo albums and will have to have the picture digitized and sent by someone else since my email program wont allow me to send photos right now. A little upgrading in size should make the QM work fine on an H28._____Grant.

[Chrisc]

That would be most appreciated. Thank you.

[Snowpetrel]

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 and fabric 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.

Cheers

Ben

[rebel heart]

Have you read that book by bill belcher? Lots of neat stuff in there too.u

[model 10]

I built a vane from 3/8 al tube and covered it with aircraft polyester fabric. You just glue it on the tubing then shrink it with a heat gun. It comes out very nice and smooth. Mine is for an Aires and I made it a little larger.

[Chrisc]

Thank you for all the info.
I know that vertical axis vanes are not as efficient as the horizontal axis types, but I want something easily repairable anywhere and with a very simple linkage. Experience has taught me that friction is the enemy of light weather self steering performance and the linkage complexities are considerably reduced with vertical axis vanes.
Apart from all this, I just want to build a vertical axis type as I just plain enjoy messing about with self steering.
Chris

[engele]

Hydrovanes use an air vane similar to what you describe.

[Capt Rottnest]

I'm building a horizontal axis, flip flop vane from Belcher's book (OGT MkII) to link to a trim tab. I chose it because of the course setting control, the flipflop vanes dont need a clamp or pin to hold course (because it doesnt weather cock) while a vertical axis vane does - which I think makes it complicated and fiddly to use. I want to be able to adjust course from the cabin.

There is a design in his book that shows a flipflop vane mounted directly above the rudder with linkage to the trim tab without lines or blocks.
But anyway, have fun.

[Snowpetrel]

Originally Posted by Chrisc

...Apart from all this, I just want to build a vertical axis type as I just plain enjoy messing about with self steering.
Chris

Fair enough, I was planning to build a vertical axis vane for my folkboat with wind generator and other gear mounted at the top of the support pole, which was going to be fixed with a sleeve on bearings rotating around it where the windvane was. The vane was going to be like the Sayes rig but with an adjustable angle so I could feather it in stronger winds, and open it for power in the light stuff... But then I found a Flemming Major for sale and bought it instead. Looking forward to seeing how yours goes, all the best with it.

Cheers

[Snowpetrel]

Originally Posted by Capt Rottnest

I'm building a horizontal axis, flip flop vane from Belcher's book (OGT MkII) to link to a trim tab. I chose it because of the course setting control.

Awesome! I love his designs. Got to be the best windvane book out, I need to get myself a copy. I am planning a OGT to Auxilary rudder type myself. I might need to go to a trim tab to get the power, but I hope not as trim tabs can vibrate badly when motoring.

[charliehows]

Originally Posted by Chrisc

I just want to build a vertical axis type as I just plain enjoy messing about with self steering.
Chris

yeah, i'm with you on that - even when they dont work its a lot of fun - i worked my way up to a stainless steel horizontal vane, servo-pendulum to auxilliary rudder setup for my boat - tried a few things on the way, but it was a lot of fun, and now that its working, man i feel good every time i look at it...and i got pretty good at welding s/s on the way, a useful skill for a boatie...good luck with your project

[Capt Rottnest]

Originally Posted by Snowpetrel

Awesome! I love his designs. Got to be the best windvane book out, I need to get myself a copy. I am planning a OGT to Auxilary rudder type myself. I might need to go to a trim tab to get the power, but I hope not as trim tabs can vibrate badly when motoring.

The book was back in print only a couple years ago so they should still be available new. I chose to build up a trim tab because there are reports the vane to tiller arrangement doesn't work too well while running.