Fitting Wind vane to Boat with Davits

[briblack]

I have to agree that the arch doesn't look adequately strong for carrying a heavy RIB. Lateral loads don't seem to be addressed. Adding a windvane will be at best a challenge. If you do end up adding one that functions as its own rudder, don't overlook that it's rudder also has very significant loads that have to be transferred into the fiberglass transom.

[Pete7]

Rich, how much does that rib weigh? I thought the MG346 was a fast cruiser racer, but that relies on her being kept light. They actually displace less that my Moody 31. We have an arch, but no way am I putting a dinghy on it. We used to carry the dinghy on its side across the stern, but it just added to the weight in the stern. It now lives deflated just in front of the mast. This and some other work has resulted in a much better balanced yacht, but it has taken us some time to realise this. If you have a 50ft old long keeled tub then it wouldn't make one iota of difference, but a modern fin keeled yacht that can lift her skirts and go if you want her too, hmm it all counts.

Hate to say this, but I think you need a lighter dinghy that can go on the deck for offshore work, or in the davits for short coastal hops when you are not using the windvane. Are you also taking the kayaks?

Ivan has some Avon air floors that will roll up, either on deck or in a spare bunk for offshore.

https://www.ivanburdfieldmarine.com/boats-1

Were the photos taken in Chichester harbour?

Pete

[crankysailor]

Originally Posted by KadeyKrogen38

It us not prudent to go to sea with a dingy hanging in davits.

Bingo! first thing I thought and I can't believe it wasn't mentioned right away.. particularly cause the OP said ".. when on long passages.."

But alas.. when just cruising around they do have to coexist I suppose if one is to have the dinghy on a davit at all and the vane is not removable (is there such a thing?)

[GILow]

Originally Posted by crankysailor

But alas.. when just cruising around they do have to coexist I suppose if one is to have the dinghy on a davit at all and the vane is not removable (is there such a thing?)

Yes, there is. The autohelm I linked is just such a design.

[Matt Johnson]

Windpilots have a very similar mount to the OPs purchased Windy vane. The Windpilots are easily removed and you'll often see just the mount on transoms of boats in places where cruisers hang out. It's the best compromise in my opinion if you want davits and a vane.... don't try to make it do everything at once!

Matt

[charliehows]

looks to me like you are painted into a corner - sugar scoop + davits = no room for windvane...could be worse though, lots of other boats also include a rack of solar panels on the dinghy frame. I'd also agree with others - that structure looks well dodgy.

[roverhi]

Check out the photo near the bottom of this page to see a Cape Horn vane integrated with a dinghy on Davits. Integrated Models – CapHorn – Régulateur d’allure intégré

[Pete7]

Originally Posted by Richkayak

The Davits are solid. I had them made and they are integrated to the transom which is integrated to the sail arch, so that is solid.

I thought the wind vane that I am looking at is this:

https://windyselfsteering.com/selfst...-does-it-work/

Couple of UK versions you may like to consider for similar money but been around a while so like to be owners with real life experiences of them.

Servo Pendulum - Neptune Yacht Windvane Self Steering | Neptune Windvane

Sea Feather Wind Vane Self Steering | Dartmouth, South Devon

[Tortuga's Lie]

Of course, the other alternative is adding a solar panel or two to power a robust electronic below deck autopilot......and if you're worried about gear failure, a spare drive and computer for backup(maybe buy one used to save $$). Overall, the cost could be similar (maybe a little higher with the spare) to a custom wind vane setup......just a thought.

You could strengthen the existing arch with some diagonal struts on both sides, but it looks to me that the thing is too high, giving it a greater moment arm.

[hpeer]

I’ll end up repeating some comments, sorry. It sounds like the OP is a bit new to sailing/cruising, my apologies if wrong.

1 - I believe your boats displacement is about 8,000 lbs. I’m assuming your center console with motor will weigh in at 250-300 lbs. that’s a whole lot of weight out there, especially if it’s not secured well. If it gets loose and starts moving around it will be more fun than you desire. Probably OK for weekend trips in the Chesapeake.

2 - Frankly for my taste I would not want that much dink anywhere on a yacht of that size. I think it would be great in protected waters, tow it around, have a ball. But with any kind of sea state it would be a serious liability. Maybe a much lighter dink for longer cruises.

3 - As Mentioned Scanmar with remote mounted vane is a decent solution. I have an Aries and I think you could adapt that to a Scanmar remote vane without too much trouble. I have adapted it to a tillerpilot input. Amazingly light drive input.

4 - Depending upon what you are trying to accomplish an alternative might be to fit a CPT helmpilot. Very low power draw. The older version had a remote vane capability. I don’t know if they still offer that. Call and find out, most times the Owner answers the phone.

5 - Along the same lines you could purchase a Pealigic AP which can be fitted to a number of wind vanes and has a remote vane input option.

6 - Actually I think this is your best option all around, a Pelagic paired with a wind vane. Call Pelagic and see if they can adapt to the Scanmar. But you would not be tied to Scanmar only. I have adapted my Aries to work with the Pelagic as well. If you pair the windvane with the Pelagic you have BOTH a vane and an AP. How sweet is that!
HOLD ON: I see Scanmar is now distributing Pelagic, there you go, one stop shopping and integration.
https://www.scanmarinternational.com/

7. A word on aux rudder vanes: if you are motoring and have significant prop walk it puts a strain in the AP, and makes it unbalanced. If motoring hard it can be significant. You can easily tell by the feel of your helm, do you have to hold it over when motoring? When you put the AP in the aux rudder, take out the prop walk, then you center the boat up with the main rudder and lock it, now the aux rudder has an easier job. Ditto with weather helm, you balance the sails, but you can also balance with the rudder. With my Aries, a servo pendulum, you balance weather helm by moving the chain a link or two. Messy as chain is pretty tight.

[GazzaAntipodes]

On my yacht a 40 ft sloop I have a Fleming Global and vet is Davits.
My dinghy will be lashed to the foredeck on passages when I plan on using the vane.
Simply put the windvane to operate correctly requires free movement and clear air flow.
The dinghy on davits will impede the windvane.
My solution on my yacht works for me, when on home Berth, the windvane is off the yacht, safely stowed. My sailing is local so no problem. When I plan a trip the dinghy is stowed on the deck and the Fleming goes to work.

[Mike Paget]

Originally Posted by GILow

Yes, I looked very hard at the pictures of the boat, and even a few of the same model on various for-sale sites. Which is why I recommended the autohelm.

A). Auxiliary rudders (like the autohelm) do not need to be on the centre line of the boat. In fact, they can benefit by being slightly offset to keep them out of the turbulence of the main rudder.

B). A remote vane system like the autohelm frees you up to put the vane in a position to experience clean air flow, regardless of what you have strapped on the back of the boat.

Seriously, this one is not too hard. It just takes some lateral thinking.

One CF member just sent me photos just a few days ago of his autohelm vane which he has mounted ABOVE the davits. Perfect clear air flow up there.

I have a Hydrovane on my Westerly Corsair and dinghy on davits possibly not as high as the op has his but it works very well and it is mounted in the centre of the transom.
Mike

[GILow]

Originally Posted by Mike Paget

I have a Hydrovane on my Westerly Corsair and dinghy on davits possibly not as high as the op has his but it works very well and it is mounted in the centre of the transom.

Mike

Good to know, because the hydrovane is a seriously good bit of kit.

Do you have photos to share?

[Suijin]

I agree that the arch appears inadequately robust. There is a boat here in the harbor with a similarly designed arch that suffered a structural failure when attempting to go to windward to the Mona Passage not so long ago. It looks fine for hoisting the dinghy overnight at anchor and for lazy day sails to leeward, but not for much more.

I have a Monitor but no davits. I would love love love to have davits but with a canoe stern would need to build a whole arch for them. Incidentally, all the Valiants that I know that have both davits and a wind vane only use or the other at a time, removing the wind vane when using the davits and stowing the dinghy on the coach roof when using the wind vane.

The Monitor is fairly sensitive to airflow, and anything at the stern that interferes with that reduces it's effectiveness. The more crap you have back there the less able the windvane will be on anything other than a downwind run.

I don't see how you could install the Monitor top assembly "remotely", offset from the center of the boat. Just does not seem plausible to me. If the OP really wants to pursue a wind vane, the Auto-Helm seems like the best solution given it's horizontal wind paddle. But it's going to interfere with the use of the sugar scoop on some level.

Someone suggested just adding more solar and forgetting the wind vane entirely. That is something to consider in this day and age of more efficient solar and improved autopilots. On a long passage, so what if you have to run the engine for a few hours a day to charge? A modern autopilot will do a better job of steering the boat than a wind vane on pretty much every point of sail and in any sea state.

As a solo sailor I like having the wind vane as a back up, and it has been pressed into service as such on a couple of occasions. I also use my Monitor with frequency because I just plain enjoy it. But on any passage where you have several crew it's much less critical.

If I were in the OP's position I would just forget the wind vane entirely unless I was planning a few ocean crossings.

[wingssail]

1. I think that dingy is FAR too heavy to hang on the stern of an 8000kg boat to say nothing of 10' feet up and a pretty insubstantial looking set of davits.

Even if the davits were bulletproof strong the weight and inertia of that dingy and motor back there will be enormous. It will substantially affect the performance, stability and balance of the boat. To be honest with you I don't think any dingy should be carried at sea on davits. Get a much smaller and simpler dingy and carry it forward (or rolled up and below, like I do).

2. Sorry, but my experience with a servo pendulum windvane tells me that your unit is marginal. There are strong forces applied to the windvane structure in periods of high winds and big waves. The small footprint of the mounting base of the Windy unit would certainly have resulted in it having been ripped off the stern of my boat on some of our crossings. So I think this one is inadequate, (my opinion only).

You have a nice boat. I know you are not about to follow this advice, but I would remove the davits and the arch and get a smaller roll up dingy and a more substantial wind vane and enjoy a terrific sailing boat without the worry of what is happening at the stern.