Dear wind vane DIYers, professionals, or physics teachers,
I've looked but couldn't find a photograph of a wind vane on a transom / rudder type which is exactly like mine. The Adams 31, as the pictures below show, has a reverse transom and a rudder which is flush with the transom and almost follows the angle of the transom.
In all the installation pictures I can find the unit is installed in a vertical position (when looking from the side). Is this necessary? This would mean a very elongated installation to avoid the servo blade hitting the rudder. I find long support arm installations like those on transom-hung rudders make wind vanes look overly large and ugly.
Or is it possible to follow the line of a reverse transom in order to avoid the need for those long tube arms and so that the servo blade doesn't contact the rudder? (diagram 1)
<div>Or, is it possible to install the main part of the unit normally (vertically) but have the servo blade offset to follow the line of the rudder? (diag. 2)
I would need to modify the actual vane (tilt it aft) so that it maintains it's 'angle of attack' to the wind but I'm not sure if installing it in this way would change the physics of the vane so that it doesn't function as designed. I also don't know what, if anything, tilting the rudder like this would do.
I'm interested in a vane but I'll be thinking twice if a massive sticky-out mounting makes my boat look like it has a sputnik on the back and have to pay more $ for slipping / marina berths.
I sent an email to Fleming but haven't heard back yet.
www.google.com.au/search?q=sailboat+self+steering+wind+vane&client=ubuntu&hs=d5X&channel=fs&biw=2560&bih=969&tbm=isch&tbo=u&source=univ&sa=X&ei=5aWfVdCELYTsmAWfyYvAAw&ved=0CCkQsAQ#imgrc=kidwezZ-uiJvAM%3A
www.google.com.au/search?q=reveres+stern+wind+vane+mounting&client=ubuntu&hs=NAY&channel=fs&source=lnms&tbm=isch&sa=X&ei=C6efVciQPIXXmAXzr6bAAg&ved=0CAcQ_AUoAQ&biw=2560&bih=969
try this one Dr
Same transom but there's no rudder to be seen there, HG. The post is dropping straight through where my rudder would be.
A fair bit to read but for anyone considering self steering this a worthwhile download.
www.windpilot.com/n/pdf/bookeng.pdf
The simplest way is to invest in one of the Sailomat 700 series. These use the oar sloping back to help with feedback. They use a modified Z crank design to rotate the oar versus bevel gears in most vanes though I have seen them with bevel gears I think. Bevel gears give automatic feedback. The other choice is build a Hebridean, one of our fellow listers is off sailing with one now. avoid.rocks/blog/the-hebridean-wind-vane-self-steering-gear/ That not him though.
If it was me I would build a unit similar to mine with the oar sloped back to match your rudder blade. The angle on the bevel gears would not be ideal but by careful selection they could be made to work. The oar blade may need to be a few inches longer though.
This is a photo of my first vane I built for my last yacht. Its a modified Walt Murray design. I made the oar slope to clear the rudder blade. It's fitted here on Ramona while I built the new one. Note the Z crank sliding through a plastic block. Quick and easy to build, plastic bearings.
[URL=.html] [/URL]
This is the new one with bevel gears. Delrin bearings on the oar and ball bearings on the vane.
[URL=.html] [/URL]
Short video of the new one. The other one is there too. Youtube has heaps of good stuff on windvanes.
The guy is Phil and you can post to him on the Top Hat site. BTW a solution could be the auxilliary rudder type that is offset on the transom. It will still need to clear the transom itself, but if far enough away from the rudder, could be vertical.
Actually looking at other photos of the Windhelm M the bevel gears are at 90 degrees. The shaft the whole unit rotates on slopes up! The push rod has a small plastic block with a pivot to transmit the correct angle to the small bevel gear. Very clever idea I had not noticed till now.
"DrRog if you decide to go ahead with the fabrication of self steering apparatus I may be able to assist with the rudder component." Cheers, f rant.
"Yes, with a Fleming it needs to be vertical." Cheers MB. Yes, all vertical systems are out.
"Some info and links on this forum. I'm Fishermantwo there." - yep, I already spotted that, Ramona.
"I would suggest looking at Walt Murray designs first and experimenting." I think that's what I'll do, Ramona - I think I'll start cheap and work up. I can't afford to buy a new one; it's second hand or self-build. By the way, there's 2 days left on a Fleming on Ebay starting at $1K with a $1.5K buy it now. (which is what started me on this line of thinking). I have to complete the projects I'm working on first (DIY stack pack sewn (just have to install now), build and cover a new dodger / spray hood, then some vinyl flooring).
I have a question for you, Ramona. I got this design idea in my head and I can't get it out. The Cape Horn system can be run through the transom and directly to the steering quadrant which shortens run lengths and potential play and eliminates lines in the cockpit. Do you think it's possible to take the lines from a more conventional servo-pen system and, instead of running them up to the CC wheel which then runs cables back to the quadrant, run them through the upper transom or aft deck directly to the quadrant? I mean, I think this would be possible, I just don't know how you'd stop all water ingress. Not that a bit of water would be a drama since the quadrant is contained within a space, the bottom of which is watertight and would hold many litres and could be run off somewhere else. Surely someone has thought of this before and rejected it. Is it simply the water ingress reason?
DrRog,
Have a look at the Hydrovane. It uses its own independent rudder to steer the boat, It can be mounted off center and It has no lines to the cockpit. Really nice bit of gear.
YEs,it's great value - that's why I needed to quickly come to terms with whether or not it would suit my boat. Great pieces of kit.
If you go down the path of building one DrRog, be sure to check out the Navik for a few Ideas . The Navik as no gears only linkages that control an aileron on the servo oar. It also has a quadrant that actuates the lines to the tiller so you get proportional movement and velocity from the servo oar to the tiller and a breakout protection that allows the whole servo oar to lift over an obstacle in the water, again another really nice piece of engineering.
I fitted a Navic to my Clansman and tried it out last week. It worked like a treat - I love it!
It cost $700 second hand and doesn't complain, block the toilet, need a nap, or eat all my chocolate biscuits.