Anchor Swivel

[craigsmith]

Originally Posted by Dockhead

But I can't think of any functional advantage, unlike the cases of stainless swivels and chain.

Never needs to be re-galvanized

[Dockhead]

Originally Posted by craigsmith

Never needs to be re-galvanized

Hmm, yes, but you could replace a galvanized anchor every five years (and never even bother with regalvanizing) and still never get up to the cost difference to stainless . . .

Still I admit stainless anchors are pretty and nice to handle.

[Fuss]

Originally Posted by Dockhead

It was almost impossible to get our anchor on board before we installed a swivel. Some boat/ground tackle combinations need it, some don't. Ours does. We went with a massive oversized Kong swivel to reduce the risks inherent in swivels.

The Kong swivels seem to be designed to resist the jaw spreading problem -- the jaw which goes on the anchor shank is held together by a massive interlocking pin. And Kong gives a safe working load rating for the side loads, not just the direct pull loads. Our swivel is rated at 3000 kg safe SIDE load. Since our 12mm G40 chain is rated at 2000 kg safe working load, it seems to me that our swivel is NOT any kind of weak link. Even the side pull safe working load exceeds the chain's overall safe working load, and the swivel's straight pull safe working load is a massive 9500 kg.

The one thing which bothers me about the Kong swivels is that the pin on the chain side is held in place only by a set screw which has no provision for a locking wire. I use Loctite as recommended.

Thats why I went with a Wasi powerball swivel which I find works fine and is very strong and most importantly is easy to buy.

(I took a look around the boat yard that I am in at the moment and I would say that most of the swivels did not look safe and most showed jaw damage or jaw spreading.
If it was me I would be replacing these immediately.)

Back to the point...
On the subject of shackles, I have a van beest that I might try...its the one with a nut and split pin. The thing I dont like about it at the moment is that it does not have a nyloc nut. I would prefer a nyloc nut so now I have to get one as I am not completely happy with the nut being held with loctite and a splitpin.

The bottom line for me is this.... I am not happy to just get any shackle from the chandlery, thats why I got the big wasi swivel. Now that I am trying a good shackle (van beest), I find it difficult to buy the shackle solution that I am completely happy with as now I have to buy a galvanised nyloc.

[nigel1]

Originally Posted by john Fussell

On the subject of shackles, I have a van beest that I might try...its the one with a nut and split pin. The thing I dont like about it at the moment is that it does not have a nyloc nut. I would prefer a nyloc nut so now I have to get one as I am not completely happy with the nut being held with loctite and a splitpin.

The bottom line for me is this.... I am not happy to just get any shackle from the chandlery, thats why I got the big wasi swivel. Now that I am trying a good shackle (van beest), I find it difficult to buy the shackle solution that I am completely happy with as now I have to buy a galvanised nyloc.

Hi John,

Main part of my job is to moor oil rigs, using up to 30 tonne anchors, and 4 inch stud link chain. If a bow shackle is used in the system, it is either a Crosby or Green Pin/Van Beest, SWL 120 tonnes, and the shackle pin held in place with nut and a split pin (mind you, its a very big split pin).
If the shackle is going to be permanent, why not get a tack weld on the nut if you are unable to find a nyloc of suitable type/size. I have no idea what the thread size/type is on these shackles.

[SailFastTri]

Originally Posted by zeehag

sailfasttri-- most all the breakaways on our moorings have been from swivel failure. i see no reason to place a swivel on any kind of ground tackle, muchless for long term use--makes no sense. especially in areas with notoriously high winds.

I agree it's a potential weak point. I have never seen one fail, probably because the moorings around here must be pulled and inspected every 3 years in order to qualify for a permit. My mooring maintenance guy doesn't use any Chinese-made chain or shackles/swivels (he says it is less reliable), and replaces anything that shows wear.

90% of the failures I see are from chafe on the rope pennants, either at deck level from chocks or bow-mounted anchors rubbing -- or due to the lines getting wrapped on the chain below the ball.

Putting floats along the entire length of the mooring pennant keeps it from sinking below the ball when it goes slack. The ball should also be sized so it floats low enough so the surface above waterline slopes inward to the top and allows the pennant to pass over when the pull starts again in another direction.

Here's an image from a rental mooring failure that put a friend's boat on the rocks, resulting in $50k damage and a legal dispute with the owner of the mooring. Obviously it had never been inspected or maintained. (note the thinning of the metal in wear areas, and that loss of metal allowed the screw shackle to come loose without even turning, as evidenced by the tie wrap that is still intact.) That swivel doesn't look too healthy either.

[foggysail]

Well, I disagree with those who say a swivel has no bearing on how the anchor sets on the sea bed. In an all chain rode, a twisted rode the anchor is not free to roll as needed for setting.

And the comment on a REAL Delta......... well, both my Delta's are real. The last one I purchased from Defender Marine.

[lancelot9898]

Originally Posted by rcassano

. In the case of anchor swivels some I see on the market now look unbelievably strong. One model has a 12,000 lb SWL for 5/16 - 3/8" chain. If true, I could almost lift the boat with it.

The mantra about swivels has always been not to use one because they are a weak link but I wonder if this is still true today after looking at the construction of the new models.

I'm pretty certain that their claims are true for the SWL with a straight line pull however...it is the side loading that is suspect as the boat surges back and forth with the wind gusts.

[boatman61]

Originally Posted by zeehag

sailfasttri-- most all the breakaways on our moorings have been from swivel failure. i see no reason to place a swivel on any kind of ground tackle, muchless for long term use--makes no sense. especially in areas with notoriously high winds.

Zee... the difference of views lies in the posts.... "I use my swivel/anchor 20-30 days a year..."
Weekenders, light cruisers and day sailors will find these things fine for years as they're so lightly used... long distance folk view it differently as their conditions and anchorages/bottoms are constantly changing and often ground tackle is recieving 100% more use.
To them a pretty and functional device... to us a dangerous weakness...

[GordMay]

See ➥ Moorings Failure Analysis - Excerpted from the Monmouth Boat Club "Moorings Boooklet" at: http://www.monmouthboatclub.org/PDFfiles/moorings.pdf Cruisers & Sailing Photo Gallery

[boatman61]

Thats about it Gord...
I used to work servicing most of the moorings in Poole Harbour.. some bigger marina's/yards did their own but we covered all council owned and a lot of other yards and buisnesses one hell of a lot anyway and the replacement rates shackle vs swivel was around 15 to 1... the swivels were chewed away by constant wear...

[zeehag]

our tackle is raised every year to and including the concrete anchor block, weighing in at 2840 pounds. the swivels that broke away had been examined within weeks to months of their failure. they fail in low stress times, after the stress of 90+ mph winds and currents of 4 kts in and out 4 tidal changes daily every day--
stainless is brittle and fails. pretty, but too brittle for daily use. btw-- friend found a USED rocna--i was trying to see if i could buy it at a reasonable rate-- the store owner(oops -- former owner) said they ar e good anchors. but at 80 GAZILLION dollars, is waaay out of anyones reach except the occasional "gotta anchor out this weekend for the yacht club annual picnic" folks.
i have never heard of changing out galvanized anchors every 4 yrs--LOL-- mine are ancient and good.. genuine cqr. looking for a used genyoowine bruce. should be able to find in mexico.....
the used and rough rocna would be a good addition to my stock of used ground tackle.. but i am not just about to pay retail for anything--i was raised "right"..LOL

[capnorv]

Originally Posted by boatman61

Zee... the difference of views lies in the posts.... "I use my swivel/anchor 20-30 days a year..."
Weekenders, light cruisers and day sailors will find these things fine for years as they're so lightly used... long distance folk view it differently as their conditions and anchorages/bottoms are constantly changing and often ground tackle is recieving 100% more use.
To them a pretty and functional device... to us a dangerous weakness...

Sorry I can't be underway everyday Mr. Boatman. I do keep the boat on the mooring outside the house the rest of the time. After being aboard for 5 years, my wife and I chose to take custody of my grandchildren 3 1/2 years ago and our state required us to have a house. Sometimes you don't know how the dice will roll, fair winds

[squarerigger]

Zeehag:
I have a #66 genuine Bruce i'm not using any more, don't want 80 gazillion bucks for it and I'm just up the bay from you if you're interested.
Ray

[boatman61]

Originally Posted by capnorv

Sorry I can't be underway everyday Mr. Boatman. I do keep the boat on the mooring outside the house the rest of the time. After being aboard for 5 years, my wife and I chose to take custody of my grandchildren 3 1/2 years ago and our state required us to have a house. Sometimes you don't know how the dice will roll, fair winds

Hi Cap... was not being personal or sarcastic... that was and is, a general fact of life.. the majority of boat owners are very lucky if they get to manage 1 or 2 mths a year on the boat... usually in familiar waters and the rest of the time at a slip or a mooring...
If you look at the anti swivel voters you'll see they're folks who have done or are doing voyages with a great variety of bottoms and currents and the last thing one needs is one more possible weakness in the ground tackle... thats why many carry a variety of anchors as well..
They're great for certain cases.. in others not so great..

[craigsmith]

Originally Posted by boatman61

If you look at the anti swivel voters you'll see they're folks who have done or are doing voyages with a great variety of bottoms and currents and the last thing one needs is one more possible weakness in the ground tackle... thats why many carry a variety of anchors as well..

That's rubbish, I can show any number of counter examples. Swivels have several possible and perfectly valid functions, depending on the set-up, and quality examples are perfectly reliable and safe. The comment on variety of anchors is nonsense too. Quit with the FUD.