Why does the anchor shackle Kink like this?

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Why the twists?

The chain or nylon has twists in it , and as it comes under tension shares the twist end to end.
 
Marin,
You beat me to the post.
I anchor in a giant bath tub and I bunk in the wheel house.

If I ever leave the Sound you better believe I will take all the things gleaned from other boaters on this forum into account.

For now the swivel works. Not only does it prevent the chain from kinking, it also fits nicely*through the bow roller and chain gypsy.

Question. If these things are so bad. Why does anyone even sell them. Would not a broken swivel be cause for a law suit if failure contributed to the sinking of ones boat?

SD
 
This article came out of the May 15, 2009 Electronic Latitude.* I figured it's worth the post since we are talking about swivals.

Larry/Lena
Hobo KK42
La Paz, BCS, MX


"After thoroughly enjoying Sea of Cortez Sailing Week, we were anchored at San Evaristo on Easter Sunday," write John and Gilly Foy of the Alameda and Banderas Bay-based Catalina 42 Destiny. "The wind was blowing at 14 knots when we realized we were dragging. This was a surprise it had blown much harder the night before and it wasn't blowing hard enough to cause our 55-lb Delta to trip. It was well set in sand with plenty of scope on an all-chain rode. We fired up the engine and tried to raise the anchor. Unfortunately, it was no longer at the end of the chain! After getting over the shock of seeing nothing but chain, we deployed our Fortress back-up anchor and spent the balance of the afternoon considering how lucky we were that it hadn't happend at night or while we were ashore.

"Turns out the stainless steel swivel between the anchor and chain had come apart. We'd purchased it 3.5 years ago from West Marine for about $110. Having read several reports in Latitude that some swivel shackles of this type seem to be prone to failure, we took it back to West Marine for their opinion. We were assured that ours was one of the "good ones." For the record, our swivel has a logo that looks like 'CKN' and beneath it 'Italy'. On the other side it says 'INOX AISI 316, SWL Kg 2000'. All this comes from the remaining half of the shackle that was attached to the recovered anchor.

"Some cruisers have speculated that the pin was not properly set, while others believe the pin simply broke. All we can say is that we'd periodically inspected the shackle and everything looked to be in good shape. Unlike some swivels, ours was designed to better withstand loads from some directions than others. Whatever the reason for the failure, we now have an old fashioned galvanized shackle that is wired shut, and have no plans to go back to a stainless swivel-type shackle.

"We know of two other boats in Mexico this season who have had similar swivels part. Fortunately, there was no serious loss of property, but neither was able to recover their anchors. We suggest that anyone with this type of shackle strongly reconsider using it. For us, continuing to use it would result in too many sleepless nights wondering what's going on on the bottom, even in relatively light winds and current."
 
skipperdude wrote:Question. If these things are so bad. Why does anyone even sell them. Would not a broken swivel be cause for a law suit if failure contributed to the sinking of ones boat?
Click to expand...

That's a good question.* I don't think it's a matter of swivels being "so bad" although I guess there are some that are poorly made.* In the article Larry quoted above it would be very interesting to know how the author had fastened the swivel to the anchor.* If it was "backwards" the swivel pin could have failed for the reason I outlined earlier (from Earl Hinz's book).

*

But I think it's more a matter of the potential for failure that causes a lot of boaters who anchor a lot to do without them.* Obviously most boaters who use swivels don't have problems (or they rarely anchor out) or we would be hearing about scores of swivel failures every year.* So I think it's more a matter of personal preference as to whether a person wants more components in their anchor rode or less of them.

*

We have never experienced a kinked or twisted chain with a swivel or without one, and we anchor in places where the boat is moved around a lot.* And like previous posters, our anchor came up "backwards" as often with a swivel as it does without one.* So I'm not convinced they really do anything worthwhile.* The theory is certainly there but I'm not sure in reality they make much difference.
 
skipperdude wrote:

Ok.*
I know these things can happen. (can and DO)

I just don't have enough experience with other than my home waters.*


*

With the greatest respect for your opinion and experience, I think your logic is flawed. Something like, I don't need a life jacket because I'm a good swimmer.

First, having spent time in the sound I can tell you that no anchorage is bomb proof at all times.* In advance of a predicted blow, we anchored in Snug harbor.* The guide books recommended it, and the name makes you think it's a good place to weather a storm.* Well, after two days of 60 knot winds, a lee shore only about 100 yards away, and two sleepless nights I was ready to get the heck out of there.* I was totally thankfull for our 350feet of all chain rode, shakeled to an oversized anchor, attached to the boat with two snubbers.* It was a wild ride.

Having anchored hundreds of times here in Alaska (where it stays light seemingly all night) I can tell you that when the anchor alarm goes off, it'll probably be in the two hours of darkness.* Trying to determine which way to move the boat into deeper water at night can reduce your life span by a few hours.* The GPS is useless in determining your direction of travel until you actually begin to move in one direction for a bit, and it always lags behind a couple seconds. Seconds you might not have on a lee shore.* If there is ANY question about the security of the anchorage, the weather or anything else, I leave the radar on standby (after having studied the picture to etch in my mind where the exit is) the GPS on, the plotter on, the depth sounder on, and the spotlight ready to go.* Often times, I'll even sleep on the bridge.

Believe me, it's total confusion when you wake in the dark and you have no idea where you are.* Traveling in the wrong direction for even 30 seconds* can put you on the rocks.

If the swivel breaks, now you have to attach another anchor, but first you have to remove yourself from harms way, and in a big blow of the type that come up in the sound, you will really have your hands full quickly.

You said,* "I am not going to loose my boat because I loose an anchor."

I hope this is true, but I'm unwilling to take an unnecessary chances, and swivels have proven to be a weak link.

In my opinion, loosing your anchor is the least of your worries. What about your life? Having stout ground tackle, properly rigged, with a minimum of weak points is the best insurance in my book.

Having said all that, I still respect other opinions and anchoring methods, but must go with what my experience as a professional mariner tells me, simple, stout and free of weak links....................................Arctic Traveller

*

*
Click to expand...

*
 
Where is snug harbor is that on the east side of the sound?

I do wear a life jacket. It makes it easier for the C.G. to find your body.

OK if I ever do venture out of the sound I will get rid of the swivel.
To tell the truth I can't say if it does it's job or not as I have never had an issue with or without it.

That being said I have a Hydraulic anchor winch that I could use to hoist the boat up a tree if I was so inclined. When I pull the lever the anchor comes up Twisted or not.* It once pulled so hard on a fouled anchor as to bend the shank on a 60# danforth. The bow roller is way over sized and I use 3/4" braided anchor line with 30 ft of 3/8" chain. This was on the boat when I got her.

If you could call a boat a truck that is what it is. I even have twin rams on the rudder.
The hydraulic hose is all 7/8" I also think I have as many anchors as Eric. So my issue was not loosing one. That is why I bought the cheep swivel.
*I don't think I would loose my life at anchor.**The boat OK but I always anchor close enough to shore to swim and if I did wind up on the rocks. I will walk to shore. I'm careful where I drop the hook.*

SD
 
I'm not sure your philosophy is one I'd care to follow but if that's the approach you prefer to take with regards to anchoring so be it. However you say you don't notice any difference one way or the other with or without a swivel, and you say you bought a cheap one which is probably not all that well made, so why not eliminate a risk potential by removing it altogether?

Coming up with a bunch of illogical (to me) rationalizations for retaining a poor piece of equipment doesn't make much sense in my book when one could simply get rid of the poor piece of equipment and eliminate the problem your rationalizations are designed to retain. Particularly in this case where getting rid of the poor piece of equipment does not require you to replace it with something better (and more expensive).
 
I'm convinced.
I'll get around to it.
Thanks
Just got a lot of things on my plate now besides I just winterized. No more anchoring till spring.
besides someone has to play the devils advocate.
No fun if everyone is on the same page.


SD
 
Even if you elect to retain the swivel, do make sure that it's attached to the anchor the right way round so that it can pivot in any direction the rode angles into the anchor from. What you don't want is to have the rode pulling sideways on the swivel which could overstrain and snap the swivel pin.* The swivel should always be able to line up with the rode no matter what the boat does in relation to the set anchor.

-- Edited by Marin on Wednesday 6th of October 2010 06:04:40 PM
 


Marin wrote:

*
it would be very interesting to know how the author had fastened the swivel to the anchor.* If it was "backwards" the swivel pin could have failed for the reason I outlined earlier (from Earl Hinz's book).
Click to expand...
*__________________________________________________________

Here's the picture of the swivel failure.* A*follow up article was written by West Marine who sold the swivel.**They took the failure quite seriously.* Installation was never mentioned.

Larry/Lena
Hobo KK42
La, Paz, BCS, MX
 
Swivel!?* Sounds like someone in marketing did a good job convincing people they needed to spend the money on one.* Your horror stories have confirmed my common sense.** OK, here is the threadbare*statement (hold your nose): a chain is no stronger than its weakest link.
 
Larry M wrote:

Here's the picture of the swivel failure.*
Click to expand...
Well, your photo tells it all.* The swivel is one of those ones that people attach with the "legs" fastened to the anchor shank, which is the wrong way to do it.* As you can see from your photo, the body of the swivel can only pivot back and forth in line with the anchor shank.* So if the boat gets off to the side of the set anchor, the swivel cannot pivot to the side*to line up with the rode.* The strain can then put enough sideways load on the swivel pin or the body of the swivel to snap it.

Had this swivel been attached to the anchor shank with a properly sized shackle, the swivel would have been able to pivot any way that was needed for it to remain lined up with the rode, and no sideways load would have been put on the swivel and it most likely would have held the load unless the swivel itself was of very poor quality.* So based on your photo and knowing no other information, I would say the fault lay with the person who installed the swivel, not with the swivel itself.

*


-- Edited by Marin on Wednesday 6th of October 2010 07:05:03 PM
 
Correct me if I'm wrong but I don't recall anyone saying *"Gee my anchor rode comes up all twisted up almost every time we use it". Nobody's having trouble so why not huck this useless thing and keep things safe and simple. The way Marin put's it side loads seem to be the problem and that situation is not unusual.

Mark,
No line is stronger than it's weakest inch either.


-- Edited by nomadwilly on Wednesday 6th of October 2010 10:23:17 PM
 
nomadwilly wrote:

The way Marin put's it side loads seem to be the problem and that situation is not unusual.
Click to expand...
That plus the fact that a swivel adds at least one more threaded pin that can back out unless it's properly safety wired.

*
 
My understanding of the reason for a swivel was not so much to allow for rotation near the anchor, but rather to prevent twisting of the rode over time swinging with the tide etc, resulting it the chain bunching up and not being able to feed nicely back into the hawse pipe, or jamming the gypsy. I have one on, and have no trouble with it, and it does make it a tad easier to rotate the anchor on the odd occasion it comes up backwards. However, I now have the opposite issue to what Marin just mentioned - of a pin backing out. Mine are now so frozen in, when I went to end for end the chain a few weeks ago, I got no further than stripping out the damn hexagonal Allen Key socket, so there was no way to shift it and remove it - so end of that plan for now. If I get serious abut my end for ending the chain, I'll have to cut the darn swivel off. If so, I'll definitely be trying it without a swivel to compare notes, so watch this space.
 
Peter B wrote:

My understanding of the reason for a swivel was not so much to allow for rotation near the anchor, but rather to prevent twisting of the rode over time swinging with the tide etc, resulting it the chain bunching up and not being able to feed nicely back into the hawse pipe, or jamming the gypsy.
Click to expand...
I know that's the theory but I have yet to meet or talk to anyone who's ever had this happen, swivel or no swivel.* Up here with our fickle winds and currents, boats rotate around their anchors (or mooring buoys) almost constantly.* The longest we have ever been anchored in one spot was three days during which I don't know how many times we've been moved completely around the anchor either by shifting winds or the four-times a day current changes.* I'm sure some of the movement cancelled out earlier movement, but between the breeze and the constant current changes the boat was never in the same spot for more than a few minutes.* We use an all-chain rode and we probably had about 150' of it out at these times.* I had removed the swivel we used to use years earlier, but each time when we went to leave the chain came up with narry a twist or kink.* At least not by the time it got to the bow roller--- I have no idea what it looked like on the seabed.

I've talked to people in our marina who we know anchor out a lot--- none of them use a swivel--- and the ones who use all-chain have never mentioned any problems with twisting or kinking.* It may very well be possible--- just about anything's possible when it comes to boating--- but if it is it seems to be an extremely rare occurance, at least in these waters.

*
 
I've always used swivels, installed correctly, and never had a problem. Never had kinks or twists, nor shackle failures. Will always use them.
 
Marin wrote:
I know that's the theory but I have yet to meet or talk to anyone who's ever had this happen, swivel or no swivel.*
Click to expand...
I remember over on PMM site there was a thread started by someone who was having big troubles with chain kinking and jamming.* Several others chimed in saying they had the same issue on occasion.* It prompted quite a bit of to & fro (that was back in the days when we had quite a few keen types on there), and in the end the upshot solution recommended was to use a swivel, so there you go........
Ralph Yost, if you are watching, You might be able to corroborate that in case my memoy is faulty.

*
 
Hey Marin
Sorry but I'm over 50 now and dont remember as much as when I was young! I dont recall the thread in PMM you refer to !

I am currently using a swivel on my chain rode. It was there when I bought the boat. I have no idea how old it is so I will replace it so I know the relative strength.

I beleive that if the swivel is appropriately chosen to be strong enough, there shouldnt be a problem. Its sort of like choosing wire size for an installation: larger size is better.

I always like to have anchor gear bigger than I "need". I will always use the largest anchor that will work on my boat, the largest chain, etc that will work.* Currently using 3/8" chain with a SuperMaxx anchor
[url]http://tinyurl.com/34dn2w9[/url]

Swivel makes sense to me but it has to be ROBUST.
R.
 
Ralph--- It was actually PeterB in Australia that recalled the article in PMM, not me. I've never read PMM other than a few articles in old copies Carey gave me.

I don't think swivels are evil. If they are installed in such a way that they cannot pivot in all directions to line up with the rode then they can break at an inopportune time.* Likewise if they are too small or poorly made.* But if they're made right and installed right there's no reason they can't remain trouble free.* We don't use one anymore because it proved to be unnecessary and we don't like any more components in our anchoring system than we absolutely need.* Which for us is the anchor, the chain rode, and a single shackle to connect them together.



-- Edited by Marin on Friday 8th of October 2010 03:32:19 PM
 
Oops. Sorry Marin. I got fooled by the quoted text. I told you I was over 50 !!!
R.
 
Most shackles are undersized for the job - not diameter but working strength. Unless you have*correctly mated a "proper" alloy shackle to your chain, you will be stuck with the galvanized junk they sell at most marine stores. And in most anchor setups I*have seen, the weakest link is*usually*the shackle. IMHO, a top notch swivel is far superior to a common grade shackle. My swivel*may eventually get replaced with a good alloy shackle, but I love the way the swivel lines up the anchor on retrieval as it enters the hawse hole.

On a separate note, SS anchors, SS shackles and SS chain are weaker than their standard steel counterparts.
 
Well,* I now have a new view on swivels.* I just returned from a tour of the USCG cutter Healy, a 420 foot icebreaker docked in Juneau.* She is the newest and most technologically advanced polar icebreaker in the US.* Everything aboard is massive including the anchor tackle.* Each link of the studlink chain must weigh 30lbs, and the SWIVEL has to be over 100lbs.* So, I guess if the USCG puts swivels on their ships, there must be a reason.* Still, I'm fine without one.................Arctic Traveller

See here at** http://www.uscg.mil/pacarea/cgcHealy/default.asp
 
The swivel might be used on the Healey, which I've seen a lot in her home berth in Seattle since the late 90s, so that her anchor will line up to the side of the ship when it's pulled into the recess in the side of the hull where it sits. It's not the sort of anchor you lean over the side and give a twist to if it comes up sideways to the hull. It would be interesting to know if other large ships with this type of anchor arrangement--- which is most of them--- also use swivels. You can't tell from the outside since the anchor shank is pulled up into the hull.
 
Marin

The answer to that is NO

The anchor whether on a large ship or small usually comes up ok without a swivel
the practice of swivels is something that I have only seen recently

I had a galvanised swivel on my boat when I bought it. Couldn't get it removed fast enough.

With the design of most anchors the twist comes out of the chain as you wind it up and the anchor will usually oweing to it's design turn itself over on the roller providing there is room to do so.

In 40 years I have not had to manhandle an anchor into the chocks as they always roll over at the last minute.

Allan
 
sunchaser wrote:

Most shackles are undersized for the job - not diameter but working strength. Unless you have*correctly mated a "proper" alloy shackle to your chain, you will be stuck with the galvanized junk they sell at most marine stores. And in most anchor setups I*have seen, the weakest link is*usually*the shackle. IMHO, a top notch swivel is far superior to a common grade shackle. My swivel*may eventually get replaced with a good alloy shackle, but I love the way the swivel lines up the anchor on retrieval as it enters the hawse hole.

On a separate note, SS anchors, SS shackles and SS chain are weaker than their standard steel counterparts.
Click to expand...
Tom, you have me confused.* You rightly criticise the shackle as often being the weakest link on an anchoring set-up, then go on to praise the superior qualities of an 'alloy' shackle, then later point out, again quite correctly, that a stainless steel part is a bit weaker than its mild steel equivalent, which of course rusts if not galvanised.
Now my understanding is, decent swivels have to be stainless, because with all the twisting the galvanised coating would soon be worn away.* However, good shackles can be just galvanised - or you put an oversized stainless one on.* My question is, what is this magic 'alloy' you are are referring to, because there is no way I would have any anchor connection made out of aluminium, which is what most people are talking about when they talk of alloy, and the only alloy I know of stronger than steel or stainless steel, is something like titanium, which I doubt is the alloy you are referring to.

*
 
The trick to shackles is no trick at all.

The best made ones are RATED , there will be a SWL load stamped or cast in to the unit.

Simply match the SWL of the chain you are using with the shackle .

Galvanizing does wear off but it takes usually YEARS before the unit looses strength.

An advantage is the galvanizing suffers when the unit is assembled , so the threads are the first to rust together.

Far better to need a hacksaw on deck to replace a shackle than have it leave at O dark 30.
 
Marin - I understand your confusion, you come from the aircraft Al side and I come from the metallurgiccal big iron side. There are dozens of alloy steels that are stronger than "mild steel." By very slight variations in the carbon, Si, Mo, Cr etc content an alloy is born.

For a quick industrial reference, pull up the 1st Chain Supply website. They note the standard steel 7/16" steel shackle with a 1/2" pin WLL at 1.5 tons whereas the same size shackle made from alloy steel carries a whopping WLL of 2 5/8 tons. The alloy steel costs a magnanimous 14 bucks vs about 6 bucks for the standard steel.

And best you do not "match" the shackle to the chain, oversize ( higher WLL) *it. WLL* is a function of a strain test not always taking into account shear, shock and loose thread pins.

-- Edited by sunchaser on Saturday 9th of October 2010 07:18:42 AM
 
It's hard for me to imagine many subjects that will spur more heated debate than anchoring or anchoring systems. Anyone care to voice their views on the effect of anchor rode color on the overall system?*
biggrin.gif
.** Personally, I'm in the rust colored camp...................Arctic Traveller
 
sunchaser wrote:

Marin - I understand your confusion
Click to expand...
I'm certainly confused over a lot of things but in this case your answer is in response to PeterB's confusion.* I just don't want to be accused of being more confused than I already am
smile.gif


But thank you for the link to 1st Chain Supply.* I am going to measure the shackle we use now to connect our rode to our anchor and see if I can't get a stronger one from them.

*


-- Edited by Marin on Saturday 9th of October 2010 02:02:06 PM
 
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