DIY self steering ?

[Ramona]

Originally Posted by Klaus-Marco

Hi folks, regarding self steering:
I have been trying to design a system that would use my main rudder, being transom hung, with an added trim tab - the trim tab being activated by either a horizontal or a vertical windvane. "Inca" being a bilge keeler would, I think, be better steered with a horizontal windvane, as they are supposed to be more sensitive and faster acting.
The vertical windvane has simpler mechanics, but does anyone know of or heard of a 29ft bilge keeler been steered by that system ? The Hasler windvane of this type uses a " differential linkage" that overcomes possible oversteering troubles...
Am I wasting my time trying to design and build something that could turn out not appropriate for my boat, a Sadler29, instead of buying a tried and tested one (2nd hand) ? of course, it's a matter of money...

First of all I would suggest reading the windvane section on this forum first. http://www.cruisersforum.com/forums/...ice-29953.html
Then think about making a Walt Murray 20/20 from this site.
https://windvaneselfsteering.com/walt-murrays-website. I made one of these a few years ago but it will cost more than $20 today. They work well but do not have the same effectiveness down wind as a bevel geared servo set up. Building one with exactly the same dimensions,ratios etc as the good commercial units is the best answer and build it out of what ever material you are comfortable with. Mine is made out of scrap SS and similar to a Monitor with ideas stolen from other units. Probably cost about $120 but many hours of labour.
This is the Walt Murray design with the Z crank, built out of scrap SS and plastic plumbing bits.

https://www.youtube.com/watch?v=U66-R0i2c20

This is my current unit with bevel gears. Since this video was made I changed to brass gears instead of Delrin. The open style of the monitor frame work makes construction and setup much easier.

https://www.youtube.com/watch?v=isw529SdN8s

[El Pinguino]

This design when modified should work on a Sadler as a trim tab on rudder .... this one has done a lot of ocean miles on the back of my 39 foot Sealord as a trim tab on aux rudder...

Custom built by my mate Inni.... he had built about 20 or more for boats from 20 to 50 feet.

Looking a bit scruffy in first pic... had just arrived in town after a sea passage...

Other shots show a bit more detail..

Needs damping lines on the tiller ( mine has a stub tiller see 3rd pic... main rudder is secured amidships ) to stop over steering and wandering...

Steers like an arrow downhill.....

[turtleofdart]

Originally Posted by TeddyDiver

You'd better to get the "Self-Steering for Sailing Craft by John S Letcher Jr".
Teddy

indeed there is lots can be done with sails alone especially if one adds what may have been called a jibboom in the past (joshua slocombe).... upwind or beam reaching most boats can be made to sail themselves with minimal gear....I am about to do some experiments with Bowsprits, rubber bands and a squaresail on my 28ft bermudan cutter (also bilge keeler)

I should be able to report back in a few weeks