Anchor Swivel Really Needed?

[Siberian Sea]

You spend good money and quality chain and anchor, you study the bottom via charts and the surrounding shoreline, you choose the best spot given all the aspects like wind, tide and other vessels near. But..... you worry about a twisted chain so all your efforts have this weak link (the swivel).
My advise is to never place a swivel anyplace in your anchor rode. Just like cheap shackles from China, this swivel might fail and you just know that’s going to happen at night in an unfamiliar anchorage when the wind is blowing and the rain...... well you all know what I’m talking about.

[WSMFP]

Originally Posted by Just Cause

Do not use Anti Seize. Use Locktite thread lock. Available at Walmart or any Automotive supply store. Blue or Red.

Mis-type on my part. Meant locktite.

[Typhoon]

We have an Ultra Anchor with the Ultra swivel . They are made to work and fit together. This makes retrying the anchor less of a chore and the are beautifully manufactured . In this world you get what you pay for , never go cheap on your boat gear.

https://youtu.be/27OJcRnO3Xg

Regards John
www.coldeh.com

[double u]

Originally Posted by Anders

My Kong swivel is much stronger than my chain. For threads I use blue Loctite.

look closely: at 90* the BL is quite low!

[NevisDog]

Originally Posted by double u

look closely: at 90* the BL is quite low!

If this means "at 90 degrees" then yes it will snap like a dry twig - but see earlier posts: these things require a few chain links between swivel and anchor so the pull is never anything other than 180. (I use half a metre of chain, so the swivel doesn't quite reach the windlass).

[billknny]

I suspect that most people who feel they need to have a swivel to avoid twists actually do not have a proper roller on the bow to align the chain. A proper chain roller should have a groove in it, so the chain links are always aligned with the windlass when they come on the boat. If you have one of those rollers, the twists are kept out in the water, and as soon as the anchor breaks free of the bottom it is free to spin and clear the chain.


If you have a smooth roller, the chain presents to the windlass with twists, and that will drive you bananas.

I don't use a swivel to keep twists of of the chain. But I use a swivel. The Mantus swivel is stronger than a standard shackle. I use it for strength.

I love the pictures of undersized, cheap, broken, swivels--that were improperly installed--presented as "proof" that swivels are bad. You gotta love the internet. You can get whatever answer you want.

[fxykty]

Funny, the instructions for the WASI swivel that came with the boat (that we’ve removed, hence this thread) explicitly state that the swivel is to be directly connected to the anchor. Like this.



While it articulates about 60 degrees through its joint, it definitely doesn’t go past that to handle 90 degree side bends. This is our setup now and you can see a slight bend in the anchor shaft (a Spade S160), I assume caused by the swivel. BTW, it’s 13mm G40 chain and a certified 16mm bow shackle.



I haven’t noticed any difference, other than feeling better not having a potential weak spot. We do have a pair of bow rollers with deep centre grooves.

I guess when anchored for an extended period in shallow water and frequent current and/or wind changes can lead to chain twists jumping out of the grooves in the bow rollers and causing problems with the windlass. But I still don’t see how those twists can possibly travel down a chain laying on the bottom and get released by a swivel that’s under tension load and can’t spin. Or can it?

Once the anchor is off the bottom it spins its twists out all on its own. The bow rollers groove keeps the chain straight for the windlass.

[Don C L]

Take a look at the strength of the swivel if you ever consider one. You’ll want the beefiest one you can find. But I was just having a related conversation with Ann, the only time I can think of when a swivel is needed is in a Bahamian mooring, and in that case it prevents two rodes from twisting together.

[thomm225]

Originally Posted by billknny

I suspect that most people who feel they need to have a swivel to avoid twists actually do not have a proper roller on the bow to align the chain.

You are forgetting those of us that bought used boats that already had a swivel on the anchor rode.

I have been so lucky that the PO set my boat up with good but very old ground tackle.

Once again on Saturday after a slow and long 20 mile sail North, I anchored just knowing I was in a good spot a bit North of the land with a forecast of 5-10 knots SSW wind.

Well I got everything but that. It was winds to 20 knots plus from all directions as a front was going thru earlier than predicted. I just hoped my old CQR would hold since I sailed into a slot with low water on 3 sides at a depth of 2'. The wind ended up being from the worst direction which was the other side of the bay 20 miles away......east which brought in beam to steep waves

Needless to say I got very little sleep.

[noelex 77]

Originally Posted by billknny

I suspect that most people who feel they need to have a swivel to avoid twists actually do not have a proper roller on the bow to align the chain. A proper chain roller should have a groove in it, so the chain links are always aligned with the windlass when they come on the boat. If you have one of those rollers, the twists are kept out in the water, and as soon as the anchor breaks free of the bottom it is free to spin and clear the chain.

A grooved bow roller will not solve the problem if your boat has spun around in the same direction enough times.

Chain will only tolerate a small number of twists for every unit of length. If you twist it more than this it starts to hockle. You cannot retrieve hockled chain conventionally.

When the twists are distributed over the total length of the rode they are not noticeable but as the chain is retrieved the twists become concentrated in the distance remaining between the bow roller and the anchor. If there are enough twists and no swivel the chain starts to hockle. If this happens when you still have enough chain out for a reasonable scope you have a problem no matter what the bow roller design.

If you can break out the anchor it will spin around underwater (sometimes very violently) and remove the twists, but at 3:1 or even 2:1 you cannot (or should not) be able to break out the anchor even with full engine power (although the torque in the chain does help with the break out by producing a significant twisting force on the anchor. Anchors, especially those models that are not very roll stable, can sometimes be twisted out at scopes where they would normally hold well.

Fortunately, this situation is not very common. The turns can only accumulate when they occur in the same direction. If the problem occurs it is unlikely to be any kind of emergency because the anchor is still holding (if you can break out the anchor the problem is solved). However, it is a pain to try and fix.

The only solution if you want to avoid this problem completely is to fit a swivel.

[eyschulman]

I use an Ultra ball in socket swivel. Jaw swivels are prone to failure due to inadequate toggle effect so I have been told by a marine surveyor. The main reason I use the swivel is not chain twist it is an upside down anchor at the bow roller on retrieval and the Ultra swivel has a flip function and is designed to right the anchor as it rolls over the roller. This actually works very well and even allows retrieval from the helm. The other reason to use a ball and socket swivel is related to the amount of force the windless has to exert to pull the anchor over the 90 degree turn. When I was considering a custom spool windless I was told that the stress on the system is considerable at this point of retrieval and often much greater than breaking loose. This is also the point where a jaw type swivel is most prone to untoggled force.

[danielamartindm]

I don't use an anchor swivel. If you do, be sure that it isn't the weak link in your ground tackle.

[Perfect Ride]

Our last 1000+ anchored nights in a cat have been using oversized Rocna as primary with galvanized O-shackle (not U, nor stainless as stainless threads can sheer) to 4 links of 10mm chain (to avoid side loads) to a quality dual action swivel and pivot to 300' of 10mm chain to 250' rode over grooved roller to a longish waterline fixed bridal that has rubberized fire hose protecting the line where it can find coral. This works when clocking for days or in high wind and wave conditions. Having said that I still check the hardware when we raise her up and I dive my anchor 90% of the time and multiple times if at anchor for long periods where we clock. This setup works very well, even in very trying (40+kt) conditions. I am more worried of chain breaking from a wrap on a coral head close to the boat when in large swell than our swivel snapping. On prior boats without swivel I would just redeploy the anchor if I was at anchor for week plus when clocking. Just haul it off the bottom and let the chain sort itself out then redeploy. From my experience either can work and be safe with proper equipment, installation, maintenance and deployment. FYI: our swivel appears to be outlasting the chain.
When done right: choose the one that lets you sleep best.

[fxykty]

I’ve re-installed the Wasi swivel that came with our boat. The various posts in this thread have convinced me that a good swivel properly installed does have a purpose, particularly if anchored shallow for a longer period of time. That’s us when we’re in the islands. Please take a look at how I’ve done it and whether it’s all good or not.

We have a Spade S140 anchor, then two 16mm hardened galvanised bow shackles, then 9 links of G40 12/13 mm chain, then a Kong SS high resistance halyard shackle, then the swivel, then the rest of the all chain rode. Each of the shackles is moused with monel wire and I’ve put plastic washers between the links and the SS shackle and swivel (no protection on the pins though, is anything possible?).

[zeehag]

gotta say i love watching the defense of a bad idea.
i donot enjoy retrieving a boat with fail swivel, and ALL swivels fail.