By bbalme - 18 Apr 2012
Is it sensible or stupid to put a swivel between anchor and rode to allow the boat to rotate around the anchor during tide changes, or stupid because its an added complication and weak link?
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By simoncurrin - 18 Apr 2012
I can 't imagine not using a swivel but obviously Daria is the expert so we will await her wise words. Simon
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By rptrsn - 19 Apr 2012
We 've been using a swivel for over 10 years of full time cruising and feel that it does make sense to use them between the anchor and chain.
We did however, learn a valuable lesson when we lost our 20Kg Bruce anchor in Porto Paulo, Sicily. The swivel failed where the pin went through the shank on the anchor. Failure was due to stress on the swivel from the sides as the boat swung and pulled to the side. Also the stress of the anchor coming over the bow roller.
We replaced the anchor and swivel (ouch) and added a shackle between the anchor to relieve the side pull stress. This made all the difference; no more worries.
Here is a picture of our Kong swivel with shackle to 10mm chain.
[attachment=15]P7130006.jpg[/attachment]
Cheers,
Pete
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By bbalme - 20 Apr 2012
I 'm interested to hear what Daria has to say about the swivel, but in the meantime I reviewed Earl Hintz 's book "The Complete Book of Anchoring and Mooring" in which his brief description of swivels starts with: "The arguments for and against the use of a swivel between anchor and rode rival those of anchor choice." and end with: "A swivel truly is the weak link in the ground tackle system and could well be a greater danger than rode twist. Treat the ground tackle system carefully and it will behave itself."
I 've taken the conclusion to heart and don 't use a swivel - but then I 'm not anchored in the same spot for weeks at a time - I tend to move from place to place...
Looking forward to seeing results of the new OCC anchor survey...
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By chrisdevans - 21 Apr 2012
We have a 32kg Delta and a high grade galvanised 4-part commercial shackle connected to around 6" of chain, THEN the Kong swivel, then the main chain. This ensures absolutely no potential problem with sideways pull (even though swivel is rated to 2T WL sideways). The issue to me is one of matching the MWL and breaking strain with all the components. No point is a 2T max working load on chain if swivel is 1T - you really do have a weak link. This assumes reputable manufacturers of components telling the truth on MWL and breaking load!!
Before this set-up we did have a mismatch with a lower grade swivel connected directly to the anchor, and over a season with many anchorages, the swivel did warp due sideways load. Luckily did not break, but easily could have in a blow.
Lesson to me is buy best possible quality components and make sure they are matched in specification, or at least the joining parts (shackles/swivels) are rates higher than the chain.
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By alshaheen - 21 Apr 2012
Chris makes an important point here - inserting the swivel in the chain rather than having one end attached to the anchor stock or even to a shackle on the stock. For the integrity of the swivel it is vitally important that it must have full articulation. We have not used a swivel aboard Al Shaheen since ours parted in Chatham Bay, Union Island one dark night and we nearly went on the rocks. During a short period of intense katabatic downdrafts the boat had sailed to the end of her scope (30 metres of 10 mm chain), several times and come up hard when the chain became taught. The gusts dropped as quickly as the came and all was quiet so we didn 't know that the swivel had parted company with the chain. When the pull of the chain on the anchor (20 kg CQR)came at an angle to the anchor stock it severly strained the fork of the swivel, resulting in the forks opening and pulling the pin out.....No connection! I 'll post a photo of the failed swivel when I can find it.
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By rptrsn - 21 Apr 2012
Chris,
Good idea on the 6" chain between the shackle on the anchor and the swivel. I think I 'll dig up a short length and give it a try! It might also make it easier for the anchor to come up over the bow roller.
Cheers,
Pete
s/y "Brilliant"
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By chrisdevans - 22 Apr 2012
Johns horrible experience with a conjoined double shackle type swivel (I am assuming from description of failure) is very much the same as where we were heading with our problem twisted swivel.
Our new one is the Kong swivel which is very clever in that there is basically a two part manufactured piece - hard to describe - so both chain and anchor connections cannot twist out like shackles can. Recommend check out Kong website/catalogue.
The Kong is more expensive than most, but seems to me to be money well spent.
The extra chain between swivel and anchor is obviously only possible if windlass is sufficiently far from roller. It also does avoid extra pressure on swivel over roller when not directly connected to anchor.
Chris
SV Tulu of Fowey
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By alshaheen - 22 Apr 2012
[attachment=16]Anchorconnector.jpg[/attachment]
Here 's the photo of the failed swivel. The opened yoke had been attched to a "D" shackle on the end of the CQR stock. The pin of the shackle was through the hole in the anchor stock and the pin of the swivel yoke was through the "D" of the shackle. I think that on one of our violent perambulations the chain must have come up tight leading almost parallel to the anchor stock causing a twist across the jaws of the yoke, which just spread them open (13 tonnes of boat travelling at 2-3 knots) and popped the pin out. This is how the swivel was when we hauled up the chain, with the other (smaller) end still attached to the chain.
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By bbalme - 25 Apr 2012
[quote="simoncurrin" post=252]I can 't imagine not using a swivel but obviously Daria is the expert so we will await her wise words. Simon[/quote]
Simon, looks like you 're in the minority regarding that use of the swivel... maybe a re-think is in order having looked at John 's picture!
As it happens we 're doing an inventory on Toodle-oo!, including all the stuff that came with the boat. In amongst the junk I found myself an anchor swivel of a type I 've not seen currently available. Good job too - it 's a ball and socket arrangement which I have to believe must be a real weak link! Hopefully it 's a discontinued item. Anyone want to buy it? :unsure:
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By simoncurrin - 25 Apr 2012
Bill yes it may be time for a re-think! What disturbs me most about John 's photo is that I think it was the the same model as ours. Looks like most people carry a lot more chain than us too so plenty of food for thought.
Simon
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By DariaBlackwell - 29 Apr 2012
Alex and I are not proponents of swivels. One of our main reasons is that you cannot see inside the housing of most swivels to be certain there is no corrosion; this is especially important for stainless steel swivels which are particularly susceptible. The Quickline cast SS swivel was recalled a couple of years ago and there was a good discussion in Practical Sailor. http://insidepracticalsailor.com/quickline-recalls-cast-stainless-steel-flip-swivels/
Friends of ours lost two SS anchors off their bow while underway. First one sheared so they replaced it with am "improved version". Then the second failed. In both cases the swivels sheared at the pin. See photos. The swivel pin was not visible inside the housing and corroded in a very short period of time. The corrosion is particularly aggressive in wet areas - like on the bow which is always subject to spray.
Ultra has created a new swivel which allows inspection of all the parts and also eliminates the need for a shackle. http://www.ultraanchors.com/ultraswivel.html They have sent us a sample for inspection and testing so we 'll let you know what we think later this season.
[attachment=22]DSC08867.JPG[/attachment]
Happy Hooking!
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By DariaBlackwell - 29 Apr 2012
By the way, another great post on the subject here by John http://www.morganscloud.com/2010/09/12/anchor-swivels/.
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By DariaBlackwell - 29 Apr 2012
Scary thought and photo John. And it would happen just when things are hairiest out there. Thanks for sharing that.
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By freyaofclyde - 29 Apr 2012
When we bought Freya our ground tackle consisted of a 30Kg claw (Bruce) and 5/16" HT chain. The two joined by a galvanised shackle. We were swithering about an anchor swivel and as we were in the USA (North Carolina) at the time, West Marine had the perfect answer, or so we thought - a swivel matched to 5/16" HT chain. We bought one, it lasted a few months before disintegrating in a 25 knot wind in the Spanish Virgins. We 've never used one since, instead we use 2 proof tested galvanised shackles.
If anyone wants a nice Bruce anchor, we can give you an approximate lat and long .... We spent 3 days trying to find it, but it was lost in the silt and the viz. was almost zero. :(
Around this time we started investigating shackles and their performance and were astounded to find the difference between the standard shackle and a proof tested shackle. Even using proof tested shackles we were not able to buy shackles that matched the size of the chain and the strength of the chain.
Knowing the inter-action between stainless steel and galvanised steel and the phenominal strength of stainless steel shackles does anyone have any comment on the use of stainless steel between the chain and the anchor on a long term basis?
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By alshaheen - 29 Apr 2012
The (top) photo on John Herries ' post is in fact a (much better!) photo by John of my failed swivel.
John F
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By alshaheen - 29 Apr 2012
Stainless steel is a tricky material at the best of times. In spite of excellent tensile strength it is susceptible to stress corrosion cracking, especially in the presence of chlorides. I would not have stainless steel in any part of my ground tackle - not shackles, anchor or chain. Remember, the strength of your ground tackle assembly is the strength of the weakest link.
There was a very revealing article on stainless steel chain published in Flying Fish a couple of years ago...
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By DariaBlackwell - 29 Apr 2012
I 'm with you John, about SS being tricky. I would not trust it for any part of the tackle arrangement, except possibly the anchor. Again PS did a good job of reviewing the issues.
http://insidepracticalsailor.com/is-stainless-steel-really-the-best-metal-for-use-in-an-anchor/
Happy Hooking!
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By freyaofclyde - 29 Apr 2012
After hearing the comments on stainless steel in a salt-water environment, there appears to be many stainless steel swivels on the market, far more than the galvanised types. As a result of the anchoring survey, can we find out what percentage of members use stainless steel or others for their swivel?
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By chrisdevans - 29 Apr 2012
As per my earlier post, we do have a stainless swivel from Kong - new this year so latest version. My understanding is that stainless only becomes a potential problem when immersed in salt water for long periods. So not useful for permanent moorings, or I guess for sitting swinging for weeks on end without raising. We sometimes sit for a few days at a time, but rarely longer, and we are always very vigilant in washing down immediately with fresh water on the swivel after use.
Is this enough? I guess time will tell.
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By simoncurrin - 29 Apr 2012
Yes we can certainly do that. Are there any othe questions people would like answering on anchoring so that I can put together a useful follow up questionnaire?
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By freyaofclyde - 29 Apr 2012
Many years ago when I was a bit less informed I used a stainless steel thimble connecting to a heavy duty galvanized shackle. This was completely submerged in salty water, part of a trot mooring system. Towards the end of the Scottish sailing season the thimble was in perfect condition, the shackle was half eaten through. It was replaced with an all galvanized system. Any comments?
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By simoncurrin - 29 Apr 2012
I have paced a new survey designed to answer the stainless debate in a new topic. called "stailess versus galvanised"
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By bbalme - 30 Apr 2012
[quote="chrisdevans" post=332]As per my earlier post, we do have a stainless swivel from Kong - new this year so latest version. My understanding is that stainless only becomes a potential problem when immersed in salt water for long periods. So not useful for permanent moorings, or I guess for sitting swinging for weeks on end without raising. We sometimes sit for a few days at a time, but rarely longer, and we are always very vigilant in washing down immediately with fresh water on the swivel after use.
Is this enough? I guess time will tell.[/quote]
If you 're only there a few days, why bother with a swivel? Instead, weigh anchor slowly and allow it to untwist.
During the off season, we always take the chain out - mainly to inspect, sometimes to re-paint markings. I guess this would be a good time to untwist the chain - if it were severely twisted - however I don 't remember any issues with twisted chain during this process - and I don 't use a swivel.
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By chrisdevans - 30 Apr 2012
Could do, Bill. Only opted for a swivel originally due to problems getting 32kg Delta aligned to come over bow roller. Twisting was a minor irritation but not a bad problem. Original swivel used in ignorance was poor quality, but nevertheless worked well with very frequent use - we live aboard and sail a lot, and do not tend to sit at anchor for weeks at a time.
The short chain between anchor and swivel, plus a high quality galvanised certified commercial shackle would seem to relieve the possibility of the sideways pull potential weakness of the swivel. Interestingly the Kong spec gives the straight line and sideways MWL of 2000kgs. This considerably exceeds both the 10mm chain and the shackle, both at around 1250/1500kgs, so is the swivel the weakest link in this configuration? I have also ensured the only removable pin in the swivel is locked with suitable adhesive. I guess if left submerged or not freshwater rinsed, corrosion could become an issue over time, but checking for that is part of the overall ongoing ground tackle maintenance.
This debate is very interesting, but the hardest part is comparing like with like - all chain or chain and rope/swivel direct to anchor or with a shackle or with a short chain and a shackle/side pull or straight pull/cheap stainless or high quality/long or short immersion/good or poor maintenance - OR any combination of the above.
Certainly there are some horror stories, but what were the combinations and was the load when failure occurred direct or sideways? Opinions seems very strong as well!! If one of the experts could assure me one way or the other that my configuration and products will work or categorically not for what I do, that would be brilliant!!
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By DariaBlackwell - 9 Sep 2012
Here 's a new post on anchor swivels that covers the pros and cons. What are your feelings on using an anchor swivel?
To Swivel or to Twist, That is The Question
To a cruiser, anchoring tackle is perhaps one of the most important pieces of gear – second only to the boat itself. As such, any mention of the pros or cons of any particular component, such as swivels, or configuration will... coastalboating.net
http://www.coastalboating.net/Features/Editorials/swivels/index.html
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By Dick - 9 Aug 2015
The use of any piece of equipment on a boat should solve a problem. I used a swivel the first 5+ years of boating as that was the recommendation at the time. For the last 30 years I have not used a swivel, 13 years being full time live-aboard.In certainly thousands, probably 10s of thousands of times where we anchored, I have never come across a problem that lead to me wishing for a swivel. The consults I have done with people and complaints were tracked often to those who lock their chain down (chain lock or in the windlass). A snubber is the answer to this as it allows free rotation which is absorbed in the snubber.
Dick Stevenson, s/v Alchemy
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By alshaheen - 9 Aug 2015
Having had a catastrophic failure of a swivel some years ago I sleep much more soundly without one and with the chain connected to the anchor with a moused shackle. I have not experienced a problem in not having a swivel.
Inevitably the chain does build up twists and normally the windlass accommodates these by the chain occasionally jumping over the socket of the gypsy (wildcat). Periodically these twists should be removed by removing the anchor and veering the first 30 or 40 metres of chain normally used, and then bringing it back aboard slowly allowing the free end of the chain to rotate. Twists do not normally come out when the anchor is attached especially if it is a large or heavy Rocna or Spade.
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By Dick - 9 Aug 2015
Hi John,
Twists in the chain may seem inevitable, but I have not had my chain ending up twisted. This may be because I use a fairly long and small diameter snubber which may absorb more twist than most. I agree that some twist may resolve itself when the chain does its occasional jumping in the gypsy. I suspect much also gets untwisted when the anchor frees itself from the bottom and while it hangs free on the way back to the boat. In any case, we agree about the need for a swivel.
My best, Dick
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By DariaBlackwell - 10 Aug 2015
Here is a report on failure of a Kong swivel. It 's a type of failure I had not seen before.
http://www.latitude38.com/lectronic/lectronicday.lasso?date=2009-05-15#.VcjUivnG-PV
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By Dick - 10 Aug 2015
Hi Daria,
Pretty dramatic pictures.
I have seen this before, but it is not as common as the "jaws-pried-open" failures that have gotten more press. With all the publicity it is hard to believe that people still attach this style swivel directly to the anchor. It is a failure waiting to happen.
My understanding of this particular failure underlines why I believe stainless steel has no place in ground tackle. I see this failure developing when side loads (or poor manufacturing) give rise to a crevice which then blossoms into crevice corrosion in hard to inspect places. This leads to the catastrophic failure that stainless steel can be prone to.
My best, Dick Stevenson, s/v Alchemy
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By shills - 18 Dec 2015
In Flying Fish 2014/2 Red Knickers covers the loss of the anchor after the anchor swivel shackle failed with bent jaws (photo pg98). This is possibly because the swivel was attached directly to the anchor shank – in fact as shown in the photo on pg14 of the same FF. This potentially puts a great deal of strain on the swivel if there is any sideways force on the anchor shank, e.g. if it gets caught on a rock or even when it re-sets itself with a wind shift. We have a short length of chain (about 1m) between the anchor shank and the swivel to avoid this i.e. anchor, 1m of chain, swivel, rest of chain. We initially did not have a swivel and had frequent problems with twisted chain – this came to a head when we were anchored in Brazil and a moored vessel dragged onto us - we had to dump our anchor and chain to the bitter end to escape, and this was slowed down by twisted chain. Since then we have always had a swivel.
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By Alex_Blackwell - 18 Dec 2015
Hi Shills
I may have posted this earlier, but here is a link to a page where we discuss swivels, where to place them (as you also suggest), and the problems associated with them.
http://features.coastalboating.net/Editorials/swivels/
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By Dick - 18 Dec 2015
Hi Shills,
Your described motive for the swivel originated (in part) by the chain not coming out of the locker smoothly and fast in a fire drill, an understandable safety concern. You also suggest prior troubles with chain twist and suggest that these problems have been alleviated by the use of a swivel.
As to chain coming out of the locker and getting jammed in a fire drill: this does not surprise me. When emerging at a moderate rate, the links can separate and flow easily, especially if there is sufficient distance from wildcat to the top of the chain pile (assuming a reasonably configured locker where chain piles do not need to be knocked over to accommodate the chain and the chain is brought in by the windlass-ie not dumped). All bets are off with a very fast rate as links will have insufficient time to separate and can easily get jammed as the chain is jumping about.
As to twist when recovering the anchor, I have never understood the forensics of how chain twist gets induced. Do you have an explanation of what takes place that your chain gets twisted?
My observation: If chain goes out un-twisted as it would if going over a free-wheeling wildcat (or even by hand) I do not see how the chain could get problematically twisted in a few days of anchoring. Maybe a few wind shifts and rotations, but these would be easily “un”-twisted when the anchor hangs free coming up to the boat and absorbed by the snubber when at anchor. So I do not see a way for twist to get induced. How do you understand it?
Probably most powerful argument for me is that in many thousands of anchoring experiences, I have yet to find a problem that makes a swivel worth the added vulnerability to my ground tackle system. The only time I wish for a swivel is when the anchor comes up in a way that makes it harder to get it onto the roller: a swivel might make this easier to remedy, but even there I am in doubt.
I would suspect that there is an alternative solution to your chain twist, but without understanding the mechanics inducing the twist, I am unable to make suggestions. I am clear that I consider swivels an unnecessary added vulnerability in a ground tackle system that should be avoided.
My best, Dick Stevenson, s/v Alchemy
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By Dick - 18 Dec 2015
Hi Daria and Alex,
I read your article on swivels and believe it to be the most thorough and thoughtful examination that I remember, and I tend to read a lot about ground tackle issues.
I agree with you that swivels have not made a case for inclusion in a ground tackle system, and that goes double for those products that are stainless steel. I think modern equipment manufacturers are selling a myth that swivels are important.
What I would wish you to consider is that you collude with this commercial myth-making on the manufacturer’s part by dedicating a long article to reviews of the various swivels, their design and materials used. I would wish first for an article examining whether they serve any realistic function: whether they actually solve a problem. And examining real world reports and investigations. This has yet to be determined and the companies should be taken to task to document their claims. Only after a realistic function is determined and documented should an article such as yours be undertaken. In some way, an article of your length and breadth gives (maybe) an unintended validity to swivels having a place in an anchoring system even with your caveats.
You conclude your review with a qualified statement advising against swivels, and then undermine this stance by essentially saying (in my reading) “whatever” when you say the choice is up to the individual mariner, which, of course, it always is and need not be stated. I may be holding you to a higher standard, as professional marine journalists, to take a position that equipment needs to be justified and should not be promoted until it has done so. I may also be picking on you as I find the marine industry journalistic efforts woefully inadequate at informing the reading public: at being more than cheer leaders for products.
My best, Dick Stevenson, s/v Alchemy
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By Alex_Blackwell - 19 Dec 2015
Hi Dick
I do agree with your sentiments and arguments. We too have anchored thousands of times, and have swung happily at anchor of weeks at a time in changing winds. Yes, the chain was twisted, but, as you correctly state, it untwisted when the anchor hung freely off the bow roller. Any twist there may have been cannot get past the gypsy/wildcat.
caveats:
Some people have complained to me that their anchor always hits the bow roller upside down. My response: remove the shackle and reattach the other way around.
For those boats where the brawny one insists on remaining at the helm and in control, and where the mate has to do the heavy work, and there is a risk of fingers getting caught righting a twisted anchor, I do recommend a swivel. In this case I recommend to look for one that actively orientates the anchor as it comes up and over the bow roller, is designed to withstand lateral loads, and has no hidden parts, where rust WILL occur.
A third caveat is on our mooring. This does not apply to every mooring. Ours is located in a hole where the water swirls around in opposite directions with the tidal flow. (Hence the reason there is a hole there.) Even with a swivel, the riser may get twisted, but the swivel does do its job and keep things right. I do have to replace the (heavy galvanised) swivel every year or so.
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By Dick - 19 Dec 2015
Hi Alex,
I suspect we could get into dangerous territory if we attempt to discuss those (usually) marital decisions which lead to the brawny one staying at the helm. In fact, this is a pet peeve of mine as it strikes me that it is (generally) a completely unnecessary decision that could be dangerous to the least brawny crew. Brawn is usually not evenly distributed among crew so jobs where occasional use of brawn (like anchor handling) can be a safety issue should go to the brawny one. Brains are usually more evenly distributed among crew and brains, with experience, allow anyone to be helm in the usually quite undemanding task of handling helm while raising anchor.
I have never solved the anchor-hitting-the-bow-roller-upside-down problem. Your suggestion is excellent for those whose chain never leaves the wildcat. When deploying the anchor, I usually “dump” a lot of chain after the anchor gets to the bottom and we have slipped a bit away and in this dumping the chain gets separated from the wildcat. So, it can be a bit of a crapshoot where the anchor will position itself upon retrieval. Those whose deployment/retrieval techniques lead the chain to always lie in the wildcat would do better for sure, but I would still doubt it would approach 100%.
In any case, it is not nearly enough of an issue to warrant the vulnerability that a swivel brings to the table. And I doubt that swivels allow the anchor to position onto the roller 100% of the time.
And agree, swivels can have a place in mooring design in certain areas. Mooring design is, in many respects, quite a different design challenge than a ground tackle system and may/likely demands an article/book of its own.
My best, Dick Stevenson, s/v Alchemy
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By Alex_Blackwell - 19 Dec 2015
Your upside down anchor issue can be solved with the right kind of swivel. There are one or two swivels on the market (we tested one) that will force the anchor to rotate in the correct orientation as it hits the bow roller. (Note that I am not naming brands here) I may not be a proponent of using swivels, but this does work 100% of the time. The one we tested also has a breaking strength that exceeds our chain.
As to moorings, we already have a section on moorings in our book. For the next edition, I have expanded this.
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By Dick - 19 Dec 2015
Hi Alex,
As said in the last email, the anchor coming up backwards on the roller is not a big deal and certainly not worth the added vulnerability of any swivel. I suspect I know I know the swivel you are referring to and it is stainless and I believe that stainless steel should have no part in any ground tackle system, regardless of breaking strength.
When last I casually went over swivel stats, the manufacturers did not specify the tests done to determine breaking strength nor did they specify safety factors. And I suspect they were not including even a little of side loading in the figures they give out. Even chain (if memory serves), a much more regulated industry, ranges from 3-1 to 6-1 in some of their safety factors.
In any case, I suspect we are spending far too long talking about swivels. Even your 3 caveats do not really apply: it is quite easy to position an upside down anchor on the occasions when that occurs; brawn can go the bow, and the third caveat applies only to moorings, not to anchoring situations and which are quite different design challenges.
I would espouse the position that swivels have no place in any ground tackle system as they only add complexity and vulnerability and any problems they solve are minor and can be gotten around easily in other ways. Certainly in everyday anchoring life, swivels are not a problem or issue. My stance is predicated on the premise that one should be prepared at all times for things to go pear shaped and ones ground tackle system is an on-board system that needs, at all times, to be bulletproof.
My best, Dick Stevenson, s/v Alchemy
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By bbalme - 19 Dec 2015
Dick, I feel your frustration! I am in total agreement with you that a swivel has no place in an anchor rode. Why anyone adds such a weak link into a critical system is nuts - doing it with a material that has inherent susceptibility to crevice corrosion is asking for trouble. The idea that it facilitates the anchor rolling onto the bow roller is a poor and frankly questionable excuse in my opinion. My anchor often comes up the wrong way round - a simple nudge with a boat hook is all it takes to turn it around.
I have to say it concerns me that Alex with his book on anchoring technique would not come down firmly on the side of eliminating swivels altogether. By all means keep them on a mooring - different situation entirely.
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By Alex_Blackwell - 19 Dec 2015
Bill / Dick
Just to set the record straight, I am also not in favour of swivels, never have been, never will. (That stated, I cannot say they do not work.)
In our book, and in discussions we try very hard to help people make their own decisions. That way they may think things through.
We feel we should not come down negatively on a given product (with the exception of the CQR ;) ) With regards to swivels, we also do state that we are not in favour of using them, or for that matter of ss components, but the decision remains with the reader.
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By Dick - 2 Oct 2016
first submitted in the Rocna section where it fit as a response to a comment. Re-submitted here as it rightly belongs under the swivel section:
Hi John,
I am glad you have had such good luck with your Rocna. It, like many of the new gen anchors, are amazing at initial setting when they are clean.
The following should be read as written from someone who believes a ground tackle system, in its proper design and execution, sometimes (perhaps often) has you and your crew’s life residing in its effectiveness. There are those that say that they rarely spend the night at anchor, usually use it as a lunch hook or for fishing: to them, I would say that it is also there for emergencies, unexpected squalls and engine breakdowns, where a good system proves itself invaluable. Those of us who cruise know how important it is at least a few times each season.
I would want you (or anyone with a swivel) to consider ditching the swivel for the following reasons:
The ground tackle system is to keep your boat and crew safe and nothing in that system should compromise that goal. I believe swivels do so compromise:
1. Attached as advertised (looking at the Ultra’s web site the installation is straight onto the anchor) introduces the possibility of the anchor getting jammed and side loads prying the jaws apart. (Google anchor swivel failures for examples.) Adding a bit of connecting chain, as Daria suggests, mitigates that issue while introducing even more shackle connections (every connection is a potential vulnerability) and the likelihood that the one favored reason for buying a swivel (clean retrieval onto a roller) would no longer work so effectively.
2. The Ultra (and most highly advertised and hyped swivels) is made of stainless steel and ss (in my judgment) has no place in a ground tackle system that, by definition, is in and out of salt water. It is potentially too brittle and prone to crevice corrosion and there are alternatives, all better, to ss shackles, anchors, chain etc. that one sees wherever there are boats.
3. With the possible exception of anchoring for long periods where the boat circles its anchor repeatedly CW or CCW (and I have lived this scenario a couple of times without a swivel), a swivel does not contribute to the effectiveness of one’s ground tackle. Chain twist is always relieved by an adequate snubber.
4. The advertised strength exceeding chain does not specify whether proof coil or high tensile. Among cruisers, HT is becoming more common. I would be in its strength if the anchor end was held rigid and the pull at right angles.
5. An anchor that comes up backward is annoying and can entail a bit of fussing, but introducing a vulnerability into one’s ground tackle system in order not to be occasionally annoyed is (again my opinion) in no way justified.
My best, Dick Stevenson, s/v Alchemy
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By alshaheen - 2 Oct 2016
This failure nearly caused a stranding on a rocky beach.
[attachment=435]IMG_1123.JPG[/attachment]
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By Dick - 2 Oct 2016
Hi John,
Thanks for this contribution.
A picture is worth a thousand words.
Dick
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