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Old 02-06-2015, 12:46 AM   #141
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If I'm being repetitive, its a bad habit

I'm not keen on swivels, people attach them incorrectly. Many swivels fail (anchors do not bend, rated shackles do not fail but swivels do (fail)).

I ask people why they use swivels - the invariable answer is 'to take out twists in the chain at a change of tide (or wind)'. The image that Noelex posted shows more twists in the chain than would be caused by simple change in tide but no-one ever says 'my chain twists on deployment' - but there again maybe people are not observant. The anchor in Noelex picture looks set 'straight' - so the twists do not seem to hinder anchor setting.

So why would people use a swivel to take out twists in a chain as a result of a change in tide? Swivels are not cheap and unless you pay an arm and a leg they are unreliable.

My belief is that people buy swivels because they think they need them, not because they do need them.

If a swivel is there to align an anchor to a bow roller then that needs to be done manually, the swivel will not do it by itself, unless you 'force retrieve'. If its simply to align the anchor then at most its a 180 degree turn, you hardly need a swivel with 2 clevis pins to create a 180 degree turn!

I'm still interested in ideas on why chain twists on deployment. I can see no disadvantage to the twists (and maybe on retrieval whatever causes the twists is reversed). But it would be 'nice' if the chain deployed untwisted.

I am equally interested in what motivates people to buy a swivel (when middle priced ones are unreliable) when all the swivel needs to do (and it can only do this with human intervention) is turn an anchor through 180 degrees at most. There are simpler, more reliable, safer means to correctly align an anchor - that do not need manual intervention (so they work with the operator at the helm).

I have seen those very sexy Ultra swivels - they extend the length of the shank which will increase the lever arm length and those shanks were ABS approved - without the swivel. The attachment of the swivel to the shank looks weak, in itself, and I wonder how many of them will bend (even before the shank). The whole basis of the Ultra is that it sets and hold tenaciously - if it does its required task it will need patience to retrieve and in choppy water you will have huge snatch loads - if you must use a swivel have some articulation so that a lever load is not imposed on any part of the swivel.
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Old 02-06-2015, 01:04 AM   #142
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The thing that puzzles me regarding the theory that a swivel is necessary to remove the twists and turns an anchor rode collects on the bottom as the boat shifts above it in the current and wind and drags the rode around, is that the moment the anchor is lifted off the bottom during the retrieve, any twists in the rode are going to simply rotate the anchor until the twists are all out.

The freely rotating anchor hanging on the end of the rode IS a swivel.

So outside of the the need to be able to rotate a heavy anchor into the correct orientation to pull in over the bow roller, I am at a bit of a loss to see what value a swivel brings to the party.
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Old 02-06-2015, 01:04 AM   #143
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Jonathan(Djbanji), I`ll avoid repetition by referring you to post 119 above. Unreliable memory says another Super Sarca user on TF fitted a shackle for the same reason. The anchor still doesn`t always come up right way round, sometimes there is twist in the chain, those things did not motivate fitting a swivel. But it does set now, and the chain does not get fouled. Thoughts?
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Old 02-06-2015, 01:11 AM   #144
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I can not say with 100% certainty that the Ultra swivel will not fail. If it does have a weakness and fails It most likely would be spread far and wide by the internet as was the case for the previous class of swivels. There is also the issue of ultimate theoretical function and the practical every day use of an item. Considering your warning I would not count on the swivel in a open anchorage under survival conditions but where and when I anchor I am willing to use it until I get reports of failure or see signs of stress damage. There are so many things on my boat that might not be considered by some the ultimate or theoretical best that the swivel would have to get in a long line and be nowhere near #1.
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Old 02-06-2015, 02:05 AM   #145
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Jonathan(Djbanji), I`ll avoid repetition by referring you to post 119 above. Unreliable memory says another Super Sarca user on TF fitted a shackle for the same reason. The anchor still doesn`t always come up right way round, sometimes there is twist in the chain, those things did not motivate fitting a swivel. But it does set now, and the chain does not get fouled. Thoughts?
The last link (or the first link) on an anchor chain should be vertical. You should be able to 'count back' to the windlass and every other link (the odd numbers) should also be vertical and remain vertical to the gypsy of the windlass. Equally the second link should be horizontal and every even numbered link should be horizontal. If this is not the case (its easily remedied) then it is inevitable that the anchor will arrive at the bow roller out of alignment. If you have never done this - its worth checking!

You can of course do this with a swivel in the assembly - but the anchor can rotate on the swivel, half a turn - and all that perfection and the usefulness of the swivel is 'lost'

This is on the basis you have one only rated, bow shackle with the shackle pin through the chain, that vertical link.

If the last link is not vertical then:

Cut that link off.

Or

take all the chain out of the gypsy and twist the chain so that the last link is vertical.

One thing that happens - that last link corrodes and wears much more than any other link on the chain. Every so often people cut that last link off, and reattach the anchor. if the last link was vertical and they only cut one link off, or cut 3 links off - then the new last link is the wrong orientation and the anchor will arrive at the bow roller with the wrong alignment.

Its easily done - back end of last year I was setting up an anchor/shackle assembly with one of AR's Boomerangs for someone (who was going down to Tasmania from Sydney) - despite knowing all this I did it wrong (and had to redo).

In my experience of swivels, expensive or cheap, they lack the bearing surface sufficiently efficient to guarantee the anchor will rotate exactly correctly to ensure the anchor is perfectly aligned when it reaches the bow roller. The choice is, get down to the bow and twist the anchor by hand (its easy to do this with a swivel - as long as you can reach the anchor) or simply run the windlass and use the power of the windlass and anchor geometry to re-align the anchor - works but it stresses the bow roller and windlass shaft and the anchor rolls violently and might damage something (depends on your vessel).


Bruce - I confess I cannot understand or visualise how the chain snags on the shank. The SARCA can have a bolt with locking nut in the slot to stop the shackle sliding down the slot so the chain should have no more opportunity of snagging the shank as with any other anchor. The shackle should not 'fall under' and slide down the slot as the SARCA has those 2 lugs underneath the slot to stop this. Though if the shackle is too big - the lugs might be too small.

I lack imagination - maybe post an image?


Interestingly many marine stainless items are given a 2:1 safety factor. I note many swivels have very reassuring WLL embossed into them - but no mention of what safety factor is employed (noting that G30 chain has a 4:1 safety factor and most rated shackles a 6:1 safety factor.) I also note that every rated shackle and every link of chain from a reputable source is Proof Load tested to 2 x WLL and that, again, every reputable chain maker can supply a test certificate for every batch of chain they sell detailing the actual load at failure.

I also guess that swivels are tested 'in line' not at 90 degrees. I'd also guess most chandlers do not know what safety factor is used for stainless swivels they sell nor will they know what WLL is used for a pull at 90 degrees.

Even if nothing else a swivel acts as, minor, obstruction to setting ability. (edit and costs an awful lot of $ that could be better spent on a decent single malt or put toward a decent spare anchor close edit)

Jonathan
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Old 02-06-2015, 02:38 AM   #146
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The last link (or the first link) on an anchor chain should be vertical. You should be able to 'count back' to the windlass and every other link (the odd numbers) should also be vertical and remain vertical to the gypsy of the windlass.
Our rode is set up this way and always has been with both the Bruce and the Rocna. Doesn't make a lick of difference to how the anchor ends up hanging below the pulpit in terms of consistency.

Now our bronze bow roller is pretty wide so it's easy for the chain to take a half turn one way or the other as it comes over the roller if there's an inclination in the lay of the chain to make it do this.

Perhaps with a system with a very narrow roller that is barely wider than the chain the alignment you describe might make a difference to how the anchor ends up hanging.

On our boat the inconsistent orientation of the anchor as it hangs under the pulpit is a non-issue as I described earlier so it's not something we have pursued addressing. It's just the nature of the beast.
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Old 02-06-2015, 02:39 AM   #147
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No way my chain is one link too long or too short. There is no need for attention to such minutiae. It doesn't matter! The anchor rode, line or chain, will twist somewhat and there's nothing you can do to counter it. Nor is there a reason to.

Bring the anchor up until the anchor shaft enters the pulpit slot. Pause.....allowing the anchor to settle naturally to the heavy end down. Many anchors will reset to the proper orientation, if needed. If not, go kick it! Then continue retrieval to secure the anchor. If you have to kick it too many times, you have the wrong anchor for your boat.

My Claw anchor has never retrieved upside down....never! I suspect a Sarca or Rocna or Delta or CQR would do the same. No need to waste money on swivels or to waste chain links by cutting off that extra one. At least that's my opinion. YMMV.
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Old 02-06-2015, 08:14 AM   #148
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I have never heard of a mass failure of swivels...sure.... some,....just like dragging anchors. Nothing is perfect and failure can come from misuse, misapplication, poor installation, factory defects, lack of maintenance....etc....etc....just like any boat gear.

Mine cost about $4 as it was on sale because the galvanizing was rough....big deal ....as one use of it flattened and scraped the excess right off the critical moving area.

It is not a ball bearing swivel....but it doesn't have to be. It does the job it was designed to do just fine....which is allow me to easily orient the anchor coming aboard. That is its primary use as chain twist never really happened to excess before. Sounds like others here use it for that reason too...more for the anchor than chain.
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Old 02-06-2015, 08:22 AM   #149
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Quote:
Originally Posted by Djbangi View Post
You can of course do this with a swivel in the assembly - but the anchor can rotate on the swivel, half a turn - and all that perfection and the usefulness of the swivel is 'lost'
Bruce - I confess I cannot understand or visualise how the chain snags on the shank. The SARCA can have a bolt with locking nut in the slot to stop the shackle sliding down the slot so the chain should have no more opportunity of snagging the shank as with any other anchor. The shackle should not 'fall under' and slide down the slot as the SARCA has those 2 lugs underneath the slot to stop this. Though if the shackle is too big - the lugs might be too small. I lack imagination - maybe post an image?
Even if nothing else a swivel acts as, minor, obstruction to setting ability. (edit and costs an awful lot of $ that could be better spent on a decent single malt or put toward a decent spare anchor close edit)

Jonathan
Ok, that's it. This weekend when I go down to the boat I'm going to take the swivel out, and then we'll see if we have any more issues than we have to now. Which is never a jamming of the sliding shackle, or fouling of the chain on that shackle, but only sometimes the anchor not aligned well enough with the roller to re-align on retrieval - easily fixed as previously described.

So if Bruce has that, shank/chain jamming or fouling, then I suspect he has the wrong type and size of shackle in the anchor slot, so yes please Bruce - we need close pic of that set-up. The correct shackle size, type and fixation in the slot are all critical. I have clarified this with Rex personally several times, and mine is right. You may or may not be able to see it in these pics, so I'll take a closer one over the weekend while down there doing a djbangi and removing the damn swivel…
PS, the top 2 shots were some I took trying to demonstrate to Marin how unlikely it would be, because of the natural locking effect in the slot when the direction of pull was anything but perfectly aligned with the shank and under minimal load for the shackle to slide down and trip the anchor at a bad moment - but he remained unconvinced, I must add...
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Old 02-06-2015, 09:00 AM   #150
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I'm not a fan of swivels and I do think they are a weak link when the rode pulls them from a wide angle. I also think the through bolt swivels like Peter's may be stronger than the ball types.

And if you have a swivel the anchor will come up at random attitudes needing to be straightened before being pulled aboard over the bow roller. So what I'm saying is that the swivel creates the problem it was designed to correct. If you have no swivel and a bow roller that has a small grove in it's center I don't see how an anchor will come up/back in any orientation different than how it went down in the first place. And if you rotate the anchor on deployment so it's orientated upside down or backwards it will come up the same way. The above applies to all chain of course.

And I can add that this is a distinct advantage of the all chain rode. Unless one is fine w aligning the anchor to the bow roller frequently. Hate to point out advantages to all chain but there it is.
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Old 02-06-2015, 09:16 AM   #151
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My swivel helps correct the problem...in NO way does it CREATE the problem.

Based on another post, maybe more here, and certainly more in other threads and readings.....people find the use of a swivel beneficial and I bet they made a decision after struggling with orienting the anchor without one...like me.

Having anchored many a boat and used to teach an anchoring class at a Sea Ray dealership....and played around with a variety of anchors and rollers....thinking that one answer cures all anchor roller problems is ...well you decide.
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Old 02-06-2015, 09:36 AM   #152
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Snubber

Does anyone have opinions on snubbers like this one?
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Old 02-06-2015, 10:03 AM   #153
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I don't see chain twist as a problem, until your boat starts to list. A cure would be to pull into deeper water and let it straighten out, much like a yo-yo string. All us old farts must remember yo-yo string problems.
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Old 02-06-2015, 10:44 AM   #154
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Does anyone have opinions on snubbers like this one?
Hey, thats what I'm making!

Parts were ordered from amazon a couple days ago!
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Old 02-06-2015, 02:21 PM   #155
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Does anyone have opinions on snubbers like this one?
My only comment is that in my opinion it's not long enough. We were taught to let the chain grab down a good ten or more below the surface of the water and then let the bight of chain between the bow roller and the chain grab down considerably more then that. All that weight down low acts sort of like a kellet and helps reduce the angle of pull on the anchor.

If the thing above the chain hook is one of those rubber shock absorbers, they seem to be a bit controversial. Some people like them and some say they offer no real value in terms of shock absorbing and tend to fall apart over time. We've never felt the need for one so have had no direct experience either way.
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Old 02-06-2015, 03:35 PM   #156
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My bow is 6 feet off the water. The two lengths that make up the V are 8 feet long and the straight length with the rubber snubber is 5 feet long. I think that will put the hook about 5-6 feet under water. In the Chesapeake I have never anchored in more than 10 feet. I can see why it would be better to be longer if anchoring in deeper water. It may have been smarter to leave the loops off the ends and have longer lines that can be adjusted to the hawse pipe.
I have read that the rubber snubbers aren't any better than the stretch of the line. I will give it a try.
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Old 02-06-2015, 03:57 PM   #157
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My bow is 6 feet off the water. The two lengths that make up the V are 8 feet long and the straight length with the rubber snubber is 5 feet long. I think that will put the hook about 5-6 feet under water. In the Chesapeake I have never anchored in more than 10 feet. I can see why it would be better to be longer if anchoring in deeper water. It may have been smarter to leave the loops off the ends and have longer lines that can be adjusted to the hawse pipe.
I have read that the rubber snubbers aren't any better than the stretch of the line. I will give it a try.
What I was thinking too...but you could make up some pairs of similar line with loops on both ends....and add them if you need more length if trying to keep it simple...


...or just add a couple of looped docklines with the non loop end fed back to the tie off point...no biggie.
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Old 02-06-2015, 04:10 PM   #158
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What I was thinking too...but you could make up some pairs of similar line with loops on both ends....and add them if you need more length if trying to keep it simple...


...or just add a couple of looped docklines with the non loop end fed back to the tie off point...no biggie.
I think I follow that , but youse guys are making me loopy!
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Old 02-06-2015, 04:41 PM   #159
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I think I follow that , but youse guys are making me loopy!
Great Loopy?
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Old 02-06-2015, 04:55 PM   #160
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I see Mantus has added the little black piece to make sure the chain does not fall out. Never had a problem with mine, yet! I have watched those rubber snubbers work on dock lines, when conditions were not so good, and they seem to work very well. Cannot see how they wont do the same on your bridle.
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