Anchor connector

Nice to see you back, haven't seen you for ages /forums/images/graemlins/smile.gif

Those ones in the picture don't look as though they are safe to 3.5 tonnes and the shape of them after 4 tonnes does not surprise me. The shackles I buy from the chandler, from Plastimo, look much more 'appropriate'. I haven't got any way of knowing, though, whether they are any good but, Mr Plastimo, if you are listening, in this litigious age you might regret it if anyone is hurt as a result of incorrect specifications.
 
Sailing season well on. Racing here, racing there and a smidgen of pre-xmas cruising. Been good.

Yeap, that's what the punter we tested that particular one said as well "Just doesn't look right". He was right.

Interesting the one in the photo is 16mm but the pin thru the middle is only 12mm. Then it was the pins that were probably going to pull out first. They are very close which is not shown well.

Just an example of manufactures 'loads'. A common situation from that part of the world sadly. A place many many 'brand names' shop in as well.
 
[ QUOTE ]
Interesting the one in the photo is 16mm but the pin thru the middle is only 12mm. Then it was the pins that were probably going to pull out first. They are very close which is not shown well.

[/ QUOTE ]I've noticed that most pins seem to be smaller than the body. I see that the load appears to have been applied to a very small part of the pin's length - as if it had been connected to another shackle, pin to pin. For some years I have tried to avoid that arrangement where possible and when maximum load is expected. I am fairly convinced that shackle-shackle connections will overstress the metal at the point of contact and that would cause the metal to deform just as your picture shows.

[ QUOTE ]
Just an example of manufactures 'loads'. A common situation from that part of the world sadly. A place many many 'brand names' shop in as well.

[/ QUOTE ]There could be a combination of sloppiness, ignorance and skulduggery but we must be sure that when a manufacturer says, say, SWL 3000kg that we are actually using the product in the configuration the manufacturer quoted the loadings for. Sadly they don't tell you under which circumstances their limits are valid. You're a chandler - can you ask Mr Plastimo, or someone?
 
Good point....

...that would also be preferable to the other "sideways forces" preventative, a bow shackle in that the flip-over ofen experience with a bow shackle cannot occur.

Steve Cronin
 
Re: Anchor connectors

---- So why buy a connector at all? ---

It's a valid question that has at least three answers that I know of.

1. Chain twisting in the anchor locker is definitely reduced by having a swivel at the anchor end. Sometimes twisting can be a major pain in the bottom as it prevents chain from running out. This can be the cause of:-
2. Chain can become jammed by twisting in the gypsy, sometimes very strongly, so that quite drastic measures are needed to free it. Naturally, this is something that one can do without when hauling anchor. It seems that fitting a swivel can reduce the frequency of this problem
3. This year I watched a crew hauling an anchor on a charter boat. As the anchor emerged from the water surface it became evident that the chain was very twisted, as it rotated violently. In doing so it knocked a large chunk of gelcoat off the bow of the boat. No doubt Sunsail will not consider this a large problem in their scheme of things but I wouldn't have been very happy with it.
 
Re: Anchor connectors

[ QUOTE ]
---- So why buy a connector at all? ---

It's a valid question that has at least three answers that I know of.

1. Chain twisting in the anchor locker........ etc.

[/ QUOTE ]

David was referring to the post where it was recommended that a short length of chain be attached to the anchor before the connector.... but then you need a 2nd connector to connect the short piece of chain to the anchor.... and so on???
 
Re: Anchor connectors

Not how I read it but I don't think it matters.

My setup is Anchor - 10 mm Wichard countersunk screw shackle - three links 10 mm galv chain - Kong swivel - 8 mm galv chain. This seems to overcome all the potential problems of jamming, lateral swivel loads, etc without becoming too ridiculous. Two 10 mm chain links would be enough but I happened to use three. I have used this arrangement all year without any problems at all.
 
Re: Anchor connectors

If all you want is a swivel, there are easier and cheaper ways. Hylas has posted a photo a couple of times in the last year
 
Re: Anchor connectors

You're right, it was a rigging toggle. I can't be sure whether he showed a solution with a swivel.
 
Re: Anchor connectors

When we pull things we try to size the bits to what would actually be used. On that one we did expect to get a bigger load (as the manufacturer had said) so used slightly bigger fittings than the chain it was going on. Doing this would help lift the tested load. We have done a few more of those types with similar results.

Most things like this are just pulled in a straight line as that would be what is expected under the biggest loads when in use. When you think about it sideloads, while being important to keep in mind, are quite low.

We have very recently done some 90 and 180 degree anchor pulls just to see what anchors do what when dragged sideways and what loads are needed. We took the opportunity to use a few swivels on the end on the anchors. Unless you are using the Steve D school of anchor system sizing (massive anchor on real small gear behind it) the swivels took a lot more than all the anchors. We put them straight onto the anchor shanks and bent 2 shanks (one being a high quality plow type surprisingly) actually while the swivels were still fine. We used 'average' sized gear not any extremes like my (tiny) or Steve D's (massive/tiny combo) type set-ups.

While I think cruisers do have to take extra care I also still think most boaters are fine putting the swivel straight into the anchor.

Obviously the above refers to good quality swivels and anchors not stuck in rocks.

Numbers used to shops and so on - We have found most shops just use what they are told by the manufacturer. Often that is perfectly fine and accurate but from certain parts of the world some numbers are listed in some quite creative ways. Heres a very common one, actual numbers from the manufacturer

8mm Chain to DIN766/A Specification -
Pitch 24mm +/- .05mm per link
SWL - 800kg
Break Load - 3200kg
Proof load - 1200kg

While that looks 'OK' it is a bit dodgy. First DIN766/A should have a tolerance of +2.5/-.05mm per 11 links. Second, going by industry standard the SWL is 1/2 the Proof load so the SWL of the above chain is actually only 600kg. Proof load is half the break load so the aboves break should say 2400kg, not 3200. That chain made by, say our Italians, has a proof load of 1600kg (recently uprated to 2000kg).

Do most (any??) of the retailers know this stuff? No sadly so just say what the paperwork says. Is it possible Plastimo, WM and all the others are just repeating what the chinese tell them? Very possible I think.

Just got our hands on a cute little tug with a couple of tonnes bollard pull, nice and bloody good fun. Daddy's got a new toy Ya Hoo!!!!
 
Re: Anchor connectors

Vyv, it's interesting to se that you don't consider a SS shackle in an otherwise galvanised set up a problem with the dis-similar metals. I'm sure that you have good reason - why please? I've always fought shy of this, but then I don't have your expertise in metals.
 
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