Anchor swivel news

[tsmwebb]

Just happened across this and though it might interest folks: http://www.latitude38.com/lectronic/lectronicday.lasso?date=2009-06-12&dayid=284#Story4

West Marine tested some Kong products after Lat38 reported a complete failure in modest conditions and, in part, concluded the following:

In a conference call with the Italy-based manufacturer, West Marine asked Kong to manufacture their products more consistently as some of the tested swivels didn't work properly right out of the package. Kong also agreed to change their packaging to instruct users to

[*]Use Blue Loctite each time the captive screw is set to ensure it doesn't back out;

[*]Inspect their ground tackle at least annually to ensure everything is operating properly and thre is no visible deformation;

[*]State the SWL and suggest using a shackle between the swivel and the shank of the anchor to prevent problems with side loads
​

That last suggests a serious defect to me. I would be very concerned if I had a Kong or similar swivel on my boat.

--Tom.

 

[Stu Jackson]

Your wrote: "
[*]State the SWL and suggest using a shackle between the swivel and the shank of the anchor to prevent problems with side loads


That last suggests a serious defect to me. I would be very concerned if I had a Kong or similar swivel on my boat."

No it doesn't. It's a recommended (and we say necessary) practice specifically because the side loads require something like the rounded shackle. Ron discussed this in the long thread about shackles and swivels and he's right.

The larger part about swivels is they are useless, essentially, in a good anchoring system. I know you are familiar with that topic, but others may want to reread the recent swivel discussion again, it was very helpful and enlightening.

 

[tsmwebb]

Your wrote: "
[*]State the SWL and suggest using a shackle between the swivel and the shank of the anchor to prevent problems with side loads


That last suggests a serious defect to me. I would be very concerned if I had a Kong or similar swivel on my boat."

No it doesn't.

Yes, it really does suggest a serious defect to me.

It's a recommended (and we say necessary) practice specifically because the side loads require something like the rounded shackle. Ron discussed this in the long thread about shackles and swivels and he's right.

That is hardly common knowledge. The manual from Kong (http://www.kong.it/catalogues/kongYachting.pdf) shows the swivel connected directly to the anchor shank and the chain. I've never seen such a device or a photo of one connected to the anchor with an additional shackle. Would that not defeat the only advantage of these devices (a smooth advance over the bow roller) anyway?

In any case I though the report of the failure, the tests and the picture of the recovered failed part all showed that using the devices according to the manufacture's instructions might result in a failure at loads well below the stated SWL of the part. You're saying that's not a problem?

--Tom.

 

[Craig Smith]

I would like to see more direct from WM, as a few things in the L38 entry make little sense to me. Kong, in their packaging and blurb, give two different SWLs: one for in-line forces, one for lateral loading. They also talk about the dangers of lateral loading in the user's guide. Moreover, the L38 thing talks about deforming at SWL. Is this really right? SWL should be something like a quarter of break. Notice that this interpretation comes only from how the statement is worded by L38; the WM quotes alone if studied on their own do not specify whether the deformation/failures occurred at or under SWL, or well beyond it.

Either way the L38 piece is unclear and poorly written.

As to swivels in general, they are typically misunderstood accessories and some of the misconceptions are present already in this thread.

Try here: www.rocna.com/kb/Swivels

 

[TimCup]

I don't believe it's a sign of manufacturing defect..

I think it's more a design thing, and not a defect as much as an inherent weakness. Swivels, by construction, don't handle lateral loads, no matter who makes them. Craig's reference on the Rocna site was helpful for me to see, and Rocna ALSO recommends not attaching the swivel directly to the anchor for the same reason.

Their solution, using chain between the swivel and anchor, accomplishes the same thing as Kong's recommendation- to minimize lateral forces on the swivel...


cup

 

[Ross]

I have a Campbell swivel between my chain and my nylon three strand rode. I rely on Campbell or ACCO products and avoid other product names.

 

[tsmwebb]

...
Either way the L38 piece is unclear and poorly written.

Well, it is just Lectronic. They claim they will do a more complete job in the July issue of the Lat38.

Did you look at the pictures here: http://www.latitude38.com/lectronic/lectronicday.lasso?date=2009-05-15&dayid=273?

Interesting to me is there is no obvious deformity at the anchor end and they don't show us (didn't recover?) the chain end... Curious. I'm familiar with the anchorage they were in and it is possible that they had a very bumpy night and veered around the anchor a bit but unlikely that their anchor was foul as the bottom is virtually all moderately hard sand. The failure in 15 knots in the morning suggests that maybe some part that was just hanging on released when the pressure came off the rode.

--Tom.

 

[tsmwebb]

...
Their solution, using chain between the swivel and anchor, accomplishes the same thing as Kong's recommendation- to minimize lateral forces on the swivel...

Sure, but at that point what's the advantage of a bolt together swivel like the Kong? Why not just use a traditional swivel that will have less leverage on the swivel when loaded sideways (eg. wrapped around a rock) and is attached with shackles with safety wire?

I don't use a swivel at all anymore but that's a different argument.

--Tom.

 

[hgrover44]

hgrover

I just attached a KONG to my 60lb.CQR that has a built in shackle. I now find that the shackle doubles back on the shank and the KONG slides laterally and gets stuck between the anchor shaft and shackle. It is a real disappointment..and I worry side load will break KONG. I am trying to find an answer without removing either shackle or KONG..I would like to have a swivel on my all-chain assembly. Any suggestions?

 

[Craig Smith]

Yes, put a few links of chain between the anchor and the swivel, as above.

 

[sailingdog]

Not a big fan of using swivels in the anchor rode...especially stainless steel ones.

 

[Ross]

My new 3 strand nylon rode had a lot of twist in it that was released when it was first used. I finally anchored out with all 300 feet of line out. I have a swivel between rope and chain. Now when I ship my anchor the rode lays fair on the deck. Before I stretched out the full length the nylon wanted to kink everytime I hauled it aboard. I don't want a swivel between my chain and anchor because I use the chain to turn the anchor to hit the bow roller properly.

 

[caguy]

I read somewhere that you can braid or weave your 3 strand rode through the chain links for about a foot for a smooth transition between the rope and chain. I tried this, haphazardly, last weekend mainly because I didn't have shackle handy. In the boat it held well and did not slip. I would be hesitant to use it in the water for fear of it loosening up. I have also seen where the rope is spliced on the last link. The problem that I have with swivels and shackels is that they hang up on my anchor roller. Any suggestions?

 

[Stu Jackson]

Chain ropde splice

Yes, caguy, bite the bullet and either learn to DIY or have a rigger splice your rode to your chain. I did it years ago, cost all of $20 and stopped the hassle of the shackle. Got new rode and chain eight years later, now have a shackle and can manage it, but liked the splice much better.

Brian Toss' Rigger's Apprentice book and Good Old Boat magazine as well as other sources have the few different splices that are recommended.

Even accidentally made up a new word: ropde

It works...

 

[Ross]

If you know how to do a back splice you can do a chain to rope splice.

 

[John]

I had a swivel because I was told that the shackle wouldn't pass over the bow roller smoothly. Then, when I read about the dangers of using a swivel I replaced it with a shackle. I have had zero problems with the shackle passing over the roller. As for twist and kinks in the anchor rode - I had that even when I used a swivel.

Anybody want to buy a good used swivel?

 

[Craig Smith]

There is no reason to get rid of a perfectly good swivel unless it turned out to be a less than stellar brand / generic thing with reason to suspect poor quality construction. There is nothing wrong with a good quality swivel; properly made and properly installed, they can be stronger than the chain. Equally, there is nothing wrong with quality stainless components in an anchor rig.

The problems come from poor quality cheap products with design not well thought out. With stainless, they come from the use of inferior grade steels, short-cuts during construction, and poor finishing. Swivels are a product that naturally cost a lot more than a shackle, and folk have a hard time facing up to the reality of the cost of good quality high strength marine grade stainless steel. If it's not 3-5 times the cost of the galvanized equivalent, a short-cut has been taken somewhere.

You are just as likely to suffer problems with cheap shackles. The difference of course is that a top quality shackle is still relatively affordable.