Anchor Swivel Really Needed?

[WSMFP]

I recently refreshed our anchoring system with 160ft of 5/16 chain, 100ft of 5/8th rode and a 35 pound Mantus on our 31ft sailboat. I ordered a Lewmar anchor swivel but I'm kinda disapointed to see there's no apparent way to seize it with wire.....unlike the shackle I'm using now to connect chain to anchor. The swivel instructions call for anti-seize to be used on the threads.

Am I being overly worried and is a swivel even needed?

[captstu]

And anchor swivel ensures you always know where your rhode will break.

That it helps make the manufactures of money.

It does not lead to better answering.

[Paul L]

Try your system without the swivel for awhile, then decide if you think you need it.
The Mantus swivel is extremely beefy and not likely to be the weak link.

[RaymondR]

Whether you need a swivel or not depends a fair deal upon how you use your boat.

I tend to spend about six months of the year moored and the other six cruising where I am changing anchorages fairly often. The moorings I use have swivels are in protected waters where loads on the system are fairly low. However, I don't trust them on my anchoring equipment. I occasionally have problems with retrieving twisted anchor chains but tolerate this for the peace of mind of not having a weak point in my ground tackle.

[boatman61]

Its not the loads that are the problem on mooring swivels.. its the wear/erosion caused by sand as the tides swirl back and forth.. in Poole harbour we used to service the moorings every winter and at least 60% of the swivels would need replacing each time.. mind.. Poole Harbour does have a unique tide pattern.
As for fitting a swivel on my anchor.. not a chance.

[fxykty]

I’m not sure how an anchor swivel is supposed to work, so somebody please explain. While there’s load on the chain, even if the last 10 or 20 m are just lying on the bottom there’s still tension in the chain and the swivel will be loaded and won’t swivel. Or will it? Once the anchor breaks off the bottom it can spin out any chain twist.

Our all chain rode had a Wasi swivel attached to the anchor, which we removed after a couple of months because it didn’t seem to have any purpose. In the year since, no problems, even when anchoring in a place where we spun around constantly for a couple of days. As long as the chain stays in the bow roller (and there’s a lot of downward force on the two inline rollers as the chain turns 90 degrees) it runs straight to the winch. Below the bow rollers the chain can be twisted, but as soon as the anchor is off the bottom it untwists itself. Without a swivel we are ensured that the anchor will always be in the correct position to seat itself in the rollers.

Anybody want a Wasi swivel sized for 1/2 inch chain?

[daletournier]

I've spent 8 years cruising mostly full time with a anchor swivel, never had a problem with swivel and my chain was never twisted.

On my new to me boat I haven't had a swivel for 18mths, the chain twists terribly before the windlass and just compounds over time. It was a bitch of a job untwisting that 90m of chain.

I only last week fitted a Mantus swivel. It is a very rugged piece of kit, it looks stronger than the chain by far.

The only swivel failures I've seen are cheap ss Chinese swivels, I've seen them break. Blanket statements "like you know where your rodes going to break) don't take into account" all swivels aren't made equally. "

I'd have faith in loctite.

[Dennis.G]

Originally Posted by fxykty

I’m not sure how an anchor swivel is supposed to work, so somebody please explain. While there’s load on the chain, even if the last 10 or 20 m are just lying on the bottom there’s still tension in the chain and the swivel will be loaded and won’t swivel. Or will it? Once the anchor breaks off the bottom it can spin out any chain twist.

In my thinking you are right.
If swivel is under a load in does not want to twist.
If swivel is under no load, there is no reason for it to twist.
So swivel does no good under normal use.

Maybe is moored for months you could get enough twists in the chain so that sufficient torque would be generated before tension locks up the swivel. I would install on a long term mooring, but I got rid of mine on my anchor and see no difference, excepting that anchor comes up over bow roller easier.

[noelex 77]

An anchor swivel is not essential. I have not used one in the last 2,000+ nights at anchor.

The only problem experienced without a swivel is in those anchorages where the boat frequently spins in circles. This introduces a twist in the anchor chain. Note: The boat does not have to traverse around the swing circle to introduce this twist, it just has to spin through 360°.

If there are enough turns in same direction, problems develop when the anchor is retrieved. The gypsy cannot pass twisted chain, so the twists become concentrated when the chain is shortened. Once the anchor breaks out of the seabed the anchor will spin (sometimes quite violently) to take out the twists. However, on rare occasions, the chain can become so twisted it starts to hockle before the scope is short enough to break out the anchor. As the gypsy cannot pass hocked chain without a swivel you become stuck, unable to retrieve enough chain to shorten the scope sufficiently to break out the anchor. Fortunately, this is a rare problem.

A swivel will allow the chain to rotate to eliminate the twist while the anchor is still buried. It has been suggested that a swivel has too much friction to allow this rotation to occur, but this is not the case. With a well set modern anchor the torque can be very significant. On occasion, I have been concened the chain will become permanently deformed by the twisting force.

[StuM]

Originally Posted by WSMFP

I recently refreshed our anchoring system with 160ft of 5/16 chain, 100ft of 5/8th rode

Just to nit-pick yet again

The whole thing, chain and rope from the bit to the anchor shackle is the "rode".

You have 100 feet of rope and 260ft of rode

[Anders]

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

[Dockhead]

Originally Posted by noelex 77

An anchor swivel is not essential. I have not used one in the last 2,000+ nights at anchor.

The only problem experienced without a swivel is in those anchorages where the boat frequently spins in circles. This introduces a twist in the anchor chain. Note: The boat does not have to traverse around the swing circle to introduce this twist, it just has to spin through 360°.

If there are enough turns in same direction, problems develop when the anchor is retrieved. The gypsy cannot pass twisted chain, so the twists become concentrated when the chain is shortened. Once the anchor breaks out of the seabed the anchor will spin (sometimes quite violently) to take out the twists. However, on rare occasions, the chain can become so twisted it starts to hockle before the scope is short enough to break out the anchor. As the gypsy cannot pass hocked chain without a swivel you become stuck, unable to retrieve enough chain to shorten the scope sufficiently to break out the anchor. Fortunately, this is a rare problem.

A swivel will allow the chain to rotate to eliminate the twist while the anchor is still buried. It has been suggested that a swivel has too much friction to allow this rotation to occur, but this is not the case. With a well set modern anchor the torque can be very significant. On occasion, I have been concened the chain will become permanently deformed by the twisting force.

This.

But there's one more good use for a swivel - to allow you to get a poorly balanced anchor right side up when you're bringing it into the roller. I needed a swivel on my previous anchor, a 121 pound Rocna. Not needed with the Spade, with the caveat that I sometimes get a tangle like that described by Noelex, when anchored for several days in a spot where you spin around with every tide change.

[a64pilot]

I second the Mantus swivel, I’m sure it’s stronger than my chain.
If you need to Loctite a swivel, I’d use red, not blue. Takes torch heat to remove, that amount of heat heat won’t hurt the swivel though.

[zeehag]

friend used a swivel between mooring pennant and tag line. i watched his boat drift away one morning with incoming tide. coulda been worse.. incoming tide only meant could ground or hit bridge...
no swivels. guaranteed way to lose. weakest link and all that mumbo jumbo which is a reality.
another friend had swivel on anchor connecting to chain rode.. we saved his drifting butt before he hit us. anchor line in water, slack, and anchor still stuck in the mud nicely. only missing thing was.... half a swivel.
nope. wont and dont.
as for twist... have raised anchor many times and yes it twists, but never unset my anchor i use bruce happily

[WSMFP]

Thanks for the comments so far. Looks like the swivel I bought is actually a maxwell and not a lewmar. I think I'm going to keep the shackle at this point and see how things go.