The 'A' word, need a connector but currently got a shackle, so....

Re: The \'A\' word, need a connector but currently got a shackle, so....

---- It was in Yachting Monthly recently, and authored (I think) by Vyv Cox who had been commissioned by YM to carry out tests on this range of connectors. ---

Just in case anyone thinks I have a hotline to YM, I proposed the tests, submitted the idea to the editor, met with the technical editor, exchanged lots of e-mails and it took two years before it finally happened.
 
Guys, guys, guys....................................

apart from a couple of rigid Kong supporters and a shackle fan, no-one has answered the question, which was which one of the 3 in the original post.
My bad for asking such an ambiguous question, I suppose.
Anyhoo. the boat is currently undergoing a few mods and at this point I have laid out both rodes. Primary is approx 225 ft of 3/8 G4 chain(which must have shrunk from the 400ft quoted in the listing), shackled to a 55lb Delta anchor. I have examined all the chain which is in good condition, but the shackle is showing a little wear, as is the slot in the Delta. So at this point I am tempted to change out the shackle and put up 3 suggestions as candidates.
This always the danger in these posts.

Incidentally the second anchor is an FX-37 with approx. 25 ft of 1/2 inch G4 chain and around 150ft of 1 inch 3 strand. I may replace the 3 strand with around 300 ft of an achor plait type of rode. I may also extend the main rode with 100 ft of the same.

Also we have never anchored this boat yet, so just taking the oppertunity to try to get things right now. The Delta may a candidate for replacement, we shall see.

I do like the Hylas solution, just need to know that I can get a suitable toggle.
 
Re: Guys, guys, guys....................................

It's because you haven't explained why you might want a swivel, other than you have the opportunity as a matter of convenience to consider one. It doesn't sound like you have any kind of problem for which they are intended to solve. Or do you?

If you don't, then continue using a shackle. Or swap it for a better one if its quality is suspect or it's undersized.

The different designs and options of swivels all have pros and cons... the right solution depends on lots of things... whether you use all chain, the condition of your roller, how much space there is between the anchor and the windlass, the width of your roller and how the anchor behaves on it, and too many more to mention...
 
Re: Guys, guys, guys....................................

Craig, as I said, I haven't anchored this boat yet. Currently it is in the US and we will be coming across the Atlantic next May to spend around 5 years cruising around the Med, so whilst I have everything apart it would seem like the ideal oppertunity to upgrade anything else.
So you are of the opinion that as I do not know what conditions I may encounter along the way, there is no reason to change anything?
Glad I didn't ask about replacing the Delta, instead of just the shackle.
 
Re: Guys, guys, guys....................................

--- no-one has answered the question, which was which one of the 3 in the original post. ---

I was under the impression that I had. If I need to spell it out, IMHO the Kong is the better choice. I would not use the rigging link as it is not intended for angular loads. If not using a swivel I would use a Wichard 17/4PH shackle, which is one of the best performers and with the countersunk pin, suitably locked, will not hang up in your bow roller.
 
Re: Guys, guys, guys....................................

[ QUOTE ]
So you are of the opinion that as I do not know what conditions I may encounter along the way, there is no reason to change anything?

[/ QUOTE ]I wouldn't. If you decide you need a swivel, re-visit the question. In the meantime just make sure the shackle is decent.

[ QUOTE ]
Glad I didn't ask about replacing the Delta, instead of just the shackle.

[/ QUOTE ]/forums/images/graemlins/cool.gif
 
Re: The \'A\' word, need a connector but currently got a shackle, so....

[ QUOTE ]
This graphs the deployed scope, i.e. increasing chain length, against the maximum tension required to introduce an upward force on the anchor (note that this is not necessarily the force required to actually drag the anchor; it is only an easily definable point to use for the purposes of these diagrams).

[/ QUOTE ]

Craig, I don't normally like to argue about anchors, but your maths and diagrams make some assumptions about small boat anchoring that leave a lot to be desired. Its all very well producing charts of the tension that will lift all the chain off the bottom, but in strong winds I don't believe all my chain EVER leaves the bottom. Even if such a tension were to apply (momentarily) the catenary has already taken up a lot of the snatch load. I don't want to get into a bit by bit criticism of your work, but there are assumptions based on assumptions leading to conclusions and its not very persuasive.

You also admit that there will still be some catenary effect with an all chain rode but in the next sentence you dismiss it.
 
Re: The \'A\' word, need a connector but currently got a shackle, so....

[ QUOTE ]
[ QUOTE ]
This graphs the deployed scope, i.e. increasing chain length, against the maximum tension required to introduce an upward force on the anchor (note that this is not necessarily the force required to actually drag the anchor; it is only an easily definable point to use for the purposes of these diagrams).

[/ QUOTE ]Craig, I don't normally like to argue about anchors, but your maths and diagrams make some assumptions about small boat anchoring that leave a lot to be desired. Its all very well producing charts of the tension that will lift all the chain off the bottom, but in strong winds I don't believe all my chain EVER leaves the bottom. Even if such a tension were to apply (momentarily) the catenary has already taken up a lot of the snatch load. I don't want to get into a bit by bit criticism of your work, but there are assumptions based on assumptions leading to conclusions and its not very persuasive.

[/ QUOTE ]As the quote says, it is only an easily definable point that does not depend on the anchor or require the definition of a constant angle.

In practice it is a relatively low point in terms of force. Typical anchor chains of are quite easily pulled bar tight, and decent anchors in decent holding will hold beyond that if at reasonable scope. That's why one uses snubbers - or is a fool not to on a small boat.

There aren't any assumptions. The only uncertainty relates to the tension generated in any particular case, which depends on the boat, but the general situation may be discussed as it is.

You are wrong - or your idea of 'strong winds' is not the same as mine.

Read Fraysse's work (Richard's link above).
 
Re: The \'A\' word, need a connector but currently got a shackle, so....

We anchored in Sardinia last year, in the same location for four nights with wind speed up to 50 knots. We were in shallow water, about 2.5 metres, with a big scope, about 25 metres of 8 mm chain out. During daytime the weather was warm, the sea likewise, and I spent a good deal of time swimming and observing my anchor and warp. I saw my chain completely leaving the bottom on many occasions, becoming very close to bar tight sometimes in gusts but noticeably all off the bottom in about 25 knots of wind.

I would suggest that with a more normal scope the chain would have lost contact with the bottom for the majority of the time.

As a result of my observations I put my Fortress kedge out at about 60 degrees from the bower. This had a remarkably calming effect on our veering and seemed to reduce the lifting of the chain. We felt far more comfortable like this and it's a technique that I will use again in such circumstances.
 
Re: The \'A\' word, need a connector but currently got a shackle, so....

Whatever scope i put out, from 4:1 to 6:1, my chain is bar tight when I reverse on it at around 2000revs. It's also almost certainly off the bottom in 25 knot winds.
 
Re: The \'A\' word, need a connector but currently got a shackle, so....

Well if that was what you observed I may be wrong, but in strong winds the angle of my chain leaving the bow roller doesn't often get near to pointing in the direction of the anchor so I am slightly confused. Bar taught isn't a very scientific statement either.

In the hurricane I was in 5 metres of water with about 70 metres of 12 mm chain out. Not much catenary to take the snatch loads in that depth. Another smaller kedge laid out to one side with a mix of chain and nylon.

The article that Craig quotes as his main source is interesting and I have read it before. The conclusion in the article that I agree with is that in extreme conditions some nylon rode to absorb some of the snatching is a good idea. As it happens we have a chain hook and I always put a length of nylon through the spare bow roller. Most of the time this is only to take the load off the windlass. I guess I will consider putting a longer length on in extreme conditions.
 
Re: The \'A\' word, need a connector but currently got a shackle, so....

-- Bar taught isn't a very scientific statement either. ---

I agree, it isn't. But most of us can recognise whether the chain follows a more-or-less straight line from the roller into the water, or alternatively if it is curved. The point made above about it being straight at 2000 rpm when reversing is a good one, as this equates to somewhere around a force 7 according to an article in YM earlier this year, reporting experience with Anchorwatch.
 
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