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  #16  
Old 11-20-2008, 08:00 PM
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rayaldridge rayaldridge is offline
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Gary-- thanks for the post and diagram--

What's the little hemispherical bump at the bottom of the skeg?
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  #17  
Old 11-21-2008, 02:47 PM
garydierking garydierking is offline
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I think it's a zinc anode to prevent electrolysis in the stainless fittings. Note the wire shown connecting the fittings.
I didn't have one fitted and after a few years I found that stainless eating worms had been busy on the bolts.

Gary
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  #18  
Old 11-22-2008, 03:21 PM
bill broome bill broome is offline
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gary d: thx for the pic. i had figured out the basic mechanics, but this gets me a better start on relative size of fin and vane. i also realized while looking at it, that the vane has to be well balanced on it's axle to prevent 'inertia' steering as the hull rolls over a wave.

farjoe, i will try to mount the device on the back of the rudder, with fin and vane on the same axis. this will eliminate most of the connecting link complexity. what remains is just the two selector disks that set the relative angle between tab and vane. it might not work due to the vane having a direct effect on the rudder through weight and windage. then, plan 'b'. and 'c'...

will need devices on both rudders, or at least a quick and easy way to move one to windward rudder. i'm going to try to put pivots above the waterline, initially. make it easier to mount and service at sea. but this might not be a good idea in a really fast boat. i'm going to be a slowish boat, for comfort.
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  #19  
Old 11-22-2008, 04:31 PM
dialdan dialdan is offline
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Hi Bill
How about you lock off the two main rudders and then use your homebuilt windvane with it,s own rudder centrally mounted on your rear beam? Hydrovane and Auto - Helm are two commercially available units that do this quite successfully I believe. Google Hydrovane and look in the photo section.
Al

Last edited by dialdan : 11-22-2008 at 04:53 PM. Reason: spelling
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  #20  
Old 11-25-2008, 10:17 PM
bill broome bill broome is offline
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i've sketched a preliminary design on my boat blog:

www.sailtherapy.blogspot.com.au
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  #21  
Old 11-25-2008, 10:21 PM
bill broome bill broome is offline
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hmmm, link has been miswritten, no .au.

www. sailtherapy.blogspot.com
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  #22  
Old 11-25-2008, 10:23 PM
bill broome bill broome is offline
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www.sailtherapy.blogspot.com

bound to get it right soon...
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  #23  
Old 11-26-2008, 12:34 AM
farjoe farjoe is offline
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Bill

your sketch is a bit too small for us (or at least me) to understand principle. Can you post a bigger picture?
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  #24  
Old 11-26-2008, 01:13 AM
dialdan dialdan is offline
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vane steering

Hi Bill
This could be worth a look . www.sailsarana.com/selfsteering.htm

Al
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  #25  
Old 11-28-2008, 08:18 AM
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Chris Bretter Chris Bretter is offline
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Wharram have a windvane system that is all wood and seems to work well
James Wharram Designs 40 pounds for the plans
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  #26  
Old 11-28-2008, 02:26 PM
bill broome bill broome is offline
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thx chris. i'll pay for plans as quick as i'll pay for sex: never that desperate. there's no hurry, i'm a hobbyist who enjoys mucking about in the shed as much as sailing. more when it rains.
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  #27  
Old 11-28-2008, 02:34 PM
bill broome bill broome is offline
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farjoe: i haven't figured out how to insert a large pic in this thread, but i have put the sketch in the 'gallery' under multihull self steerer,with some notes.
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  #28  
Old 11-29-2008, 01:57 AM
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Chris Bretter Chris Bretter is offline
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I think if you get a look at it you will be able to fabricate one its all wood and very adjustable and cheap
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  #29  
Old 11-30-2008, 12:38 AM
farjoe farjoe is offline
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Quote:
Originally Posted by bill broome View Post
farjoe: i haven't figured out how to insert a large pic in this thread, but i have put the sketch in the 'gallery' under multihull self steerer,with some notes.
thanks i will have a look
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  #30  
Old 11-30-2008, 04:17 PM
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sandy daugherty sandy daugherty is offline
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I don't understand why wind vanes are successful on a tri, and universally useless on catamarans.
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