Want To Buy: Auto-Helm wind vane self-steering

[Sails Rock]

I am looking for the upper unit of an Auto-Helm wind vane self steering system (see picture). Would also consider purchasing the whole assembly including auxiliary rudder. Unfortunately Scanmar no longer manufacture these so is there a second hand unit out there somewhere?

[surazo]

Hi SR , I'm trying to find one of this type too and at moment I has been impossible to get one .I have the base mounted in transom but I Know that they are possible to construct .If you have plans for it please share with me .Thanks

[Sails Rock]

Hi Surazo
I might yet need to design and build my own (this winter’s project) but I am trying to find a proven secondhand vane / trim tab system first. I will let you know how I get on.
Regards
SR

[surazo]

Thanks .we have a common problem and sometimes better is common solution .I ask to scanmar for this type of autopilot new or used but they don't made any of them in the last years .
I sent my boat characteristics and they will be send me a recommendation respect another windvane autopilot .
Anyway in you tube a young sailor made one that seems work really well :

https://www.youtube.com/watch?v=ZlKV...QZzT-e&index=1

It's a Hydrovane .I going to investigate about it .
regards

[hpeer]

This book has plans for auxiliary rudder vanes. I have one built by my boats previous owner and it works quite well. The book is fairly rare. The diagrams are a bit small. But it works.

https://www.thriftbooks.com/w/wind-v...dition=5370263

[surazo]

Thanks .It's temporary unavailable

[surazo]

Probably Some sailor have the plans to do one of the Autohelm scanmar windvane?
Regards
Hernan

[hpeer]

Well anyway, what Belcher does is to have the wind paddle turn a trim tab on the aux rudder. Then the aux rudder turns the boat. That way the effort required is quite light.

Abba.au seems to have some of the diagrams online. I can’t post the links, does not display well on my iPhone.

[surazo]

Hi , can you posted the entire link to Abba.au please .
I can't find the page
Thanks

[hpeer]

https://abba.org.au/

if you can find it look for APR 2015. Apparently they had a technical meeting with lots of drawings.

But also there is an active thread about “single handing wheel or tiller” or some such thing. Anyway poster Gilow is apparently building a aux vane rig and has Belchers book. I have a copy but it is 1,600 miles away.

OK, still looking.
A bit more…. http://abba.org.au/wp-content/upload...r-May-2015.pdf

[hpeer]

I can try to give a photo of my rig.

[surazo]

Thanks.it looks really good .Do you constructed or bought by pieces based in diagrams ?
Thanks

[surazo]

Thanks.it looks really good .Do you constructed all or bought some parts , based in diagrams ?
Thanks

[hpeer]

I did not make it, the PO did. He is a very talented fellow.

He built it from Bill Belchers book. Pretty much exactly as shown. He changed some of the fabrication a bit. But all the principals are identical. I really like it.

The thing is the trim tab acts a bit like a servo pendulum, a small wind force gets multiplied, albeit via a different process.

[GRIT]

Originally Posted by hpeer

I did not make it, the PO did. He is a very talented fellow.

He built it from Bill Belchers book. Pretty much exactly as shown. He changed some of the fabrication a bit. But all the principals are identical. I really like it.

The thing is the trim tab acts a bit like a servo pendulum, a small wind force gets multiplied, albeit via a different process.

Have you used this system? I notice the pivot point is near 50% of the chord, whereas a "normal" balanced rudder is somewhere around 25% of the chord. I'm just wondering how it steers? Have you hand steered using the aux rudder? Does it tend to oversteer?

It looks like a great design. I'm presently planning a similar system for our Cat. One of the major problems being that our present rudders are not balanced (they're kick-up rudders), so there's major re-working to do there before trying to have a trim tab do the steering.

Thanks in advance.
Paul.