Which way round should the shackle be?

[Stu Jackson]

Originally Posted by Cotemar

Shackle Pin should go through the chain link, so when the chain starts to turn with wind or current for a reset you will not be prying the shackle open on a side pull.

http://www.cruisersforum.com/forums/...ml#post1174022

Reply #29 and this one disagree.

It seems to me.

Is that right?

[Pelagic]

Originally Posted by Cotemar

Shackle Pin should go through the chain link, so when the chain starts to turn with wind or current for a reset you will not be prying the shackle open on a side pull.

http://www.cruisersforum.com/forums/...ml#post1174022

Cotemar…what I see in your example is a sloppy fit shank head that is subject to leverage stresses regardless of where the pin is.
If an anchor becomes wedged under a rock or bommie and the chain has the wrong wrap all kind of side stresses will happen

The extended slot has basically added a weak link and again, I believe it is to facilitate easier bow roller stowage.

Heavy walled design and tight fit as shown below is far stronger despite the marketing hype of yacht anchor suppliers.

[bobsadler]

[IslandHopper]

Originally Posted by bobsadler

Stevpris

[model 10]

Originally Posted by IslandHopper

Stevpris

They went to all the trouble to build that anchor, then they put the shackle in backwards!

[Ryan H]

You are all wrong. Shackle pin should be clockwise in northern hemisphere and counter clockwise in the southern. Better for wind resistance unless you deprive your shackle of oxygen.... probably has something to do with gravity and how the shackle, anchor, and chain all touch themselves...

Old one, but still good: How many engineers does it take to screw in a shackle......

Sent from my SGPT12 using Cruisers Sailing Forum mobile app

[JonJo]

Originally Posted by Guy

They went to all the trouble to build that anchor, then they put the shackle in backwards!

Interesting image, looks very impressive, compelling even and being so expensive it must be right - but hardly relevant. These anchors, I'm sure you will correct me if I'm wrong, are set in multiples the pull is in one direction only and for a pull in one direction the shackle with its pin precisely fitting the shank is obviously ideal.

We have covered this already but the load is at any and an unpredictable angle.

but there again if your yacht looks like an oil rig then do what they do on oil rigs

Jonathan

[IslandHopper]

So how is a ships anchor connected then...?

[Stu Jackson]

Originally Posted by IslandHopper

So how is a ships anchor connected then...?

Usually at the bow.

Pin through the anchor, chain on the curvy part.

But given this discussion, it could be the other way.

C'mon, folks, no real answer...yet?

[Andrew Troup]

Genuine CQRs also have a built-in toggle, like the big ship anchors shown.

It's not a shackle; it's not removable: the pin is fully welded both sides (as in big ship practice), before the anchor is galvanised.

The toggle and pin are NOT close fitting, either radially or axially

I can think of several reasons for choosing to fit a toggle in the CQR case:

1) They wanted the user to attach the chain using a single shackle, with the pin through the chain, but had not thought of making a shackle slot per modern anchor practice.

The slot, to my mind, is far superior.

Eliminating superflous moving parts, and extra operations (bending the toggle, welding the pin) eliminates potential failure points.

If they had thought of it, Simpson-Lawrence could have forged the CQR shank with a slot, with a convex radius to keep people like Cheechako happy. A 'modern' anchor could achieve a similar result by plunging a 'rounding-over cutter' into the aft end of the slot from each side.

Personally I think this would be a bit of lily-gilding*.

I'm not concerned about compressive local surface stress on the pin of a decent quality bow shackle, it's very low on the scale of things to worry about, considering that hundreds or thousands of butt welds are exposed to worryingly high tensile stresses, generalised across the whole section.

Tensile stresses are the worrying ones.

* If the corners were not rounded as they should be by the manufacturer (not least because galvanising does not last on any corners left square), they soon will be by the shackle working away at it.

2) Simpson Lawrence did not have to worry about unfair loads on the toggle (which, as has been pointed out, could be a worry if it were a shackle), because the far end of the shank is hinged on a CQR

[Andrew Troup]

Originally Posted by Cotemar

Shackle Pin should go through the chain link, so when the chain starts to turn with wind or current for a reset you will not be prying the shackle open on a side pull.

http://www.cruisersforum.com/forums/...ml#post1174022

Apart from the non-galvanised chain, I see NOTHING in this photo which I would not consider best practice.

[IslandHopper]

Originally Posted by Stu Jackson

Usually at the bow.

Pin through the anchor, chain on the curvy part.

But given this discussion, it could be the other way.

C'mon, folks, no real answer...yet?

Actually i was just taking the piss, i usually drive the below for a living, it's an Anchor handler, i just wanted to find out if we had been connecting our anchors correctly but it seems we haven't, well according to some in this thread...

Ships Anchor and Shackle

[IslandHopper]

Originally Posted by Andrew Troup

Apart from the non-galvanised chain, I see NOTHING in this photo which I would not consider best practice.

I would agree if the slot was rounded, but the way it is, most definitely not....

Also the correct name for the shackle on big ships is not a "Toggle", it's an end shackle, or Anchor D-Shackle, we carry a spare or two on board and they screw in the same as a normal shackle, the welding is just electronic mousing...

Anchor D-shackle, End Shackle - China Marine Anchor Chain Manufacturer, Supply

You can also get a similar type for small boats as has been shown in another thread.....

[bobsadler]

JonJo: Yes, the rig anchors are sometime "piggy backed" with a 2nd or even 3rd anchor on one anchor chain but it's far from the norm.

I'm with Island Hopper: after 37 years involvement with offshore oil and gas developments I'm glad that someone is finally setting me straight

[JonJo]

Originally Posted by bobsadler

JonJo: Yes, the rig anchors are sometime "piggy backed" with a 2nd or even 3rd anchor on one anchor chain but it's far from the norm.

I'm with Island Hopper: after 37 years involvement with offshore oil and gas developments I'm glad that someone is finally setting me straight

Actually I was not thinking of piggy backing more that each rig is secured with a web of anchors, like watch face, and each anchor is subject to a straight line pull.

But if they are only secured by one anchor rode - what happens when the wind changes?

Jonathan