Which way round should the shackle be?

[JonJo]

Originally Posted by Guy

Two shackles are kind of like a swivel, only they probably won't fail. The shackle in the anchor shank can be quite large also. The bow of a shackle is not meant to ride on the sharp edges of the slot of something like the slot in the shank of a Rocna while the pin will set nicely in that slot. I think mostly, the ability to articulate is the main feature of 2 shackles.

I've never tried 2 shackles - but in a 2 shackle system the first shackle will be 'vertical' and something potential that big (the pin end) hitting the roller of the bow roller would impose quite a large snatch? Not a big issue if you have small anchor, as you can lift the anchor over if necessary - but not such a bundle of laughs with a 40kg model.

[model 10]

Originally Posted by JonJo

I've never tried 2 shackles - but in a 2 shackle system the first shackle will be 'vertical' and something potential that big (the pin end) hitting the roller of the bow roller would impose quite a large snatch? Not a big issue if you have small anchor, as you can lift the anchor over if necessary - but not such a bundle of laughs with a 40kg model.

You would of course install the shackle in the chain to have the pin head up. It will always be aligned to the shank and the top side of the anchor. So unless you are in a really big hurry and need to stow your anchor upside down...

[JonJo]

Originally Posted by Guy

Two shackles are kind of like a swivel, only they probably won't fail. The shackle in the anchor shank can be quite large also. The bow of a shackle is not meant to ride on the sharp edges of the slot of something like the slot in the shank of a Rocna while the pin will set nicely in that slot. I think mostly, the ability to articulate is the main feature of 2 shackles.

Tested or Rated Shackles from brand name manufacturers, Crosby, Peerless, Campbell, Witchard are a bit like chain, stories of them failing are few and far between - in fact non-existent? Of the shackles I know that have failed (apart from the pin falling out) - they fail in or near the eye (not the bow). Which still makes me wonder of the need for 2 shackles.

Jonathan

[Andrew Troup]

The reason Peter S put a slot in the shank of the Rocna is to enable threading the eye of the shackle through the slot so you could fit the shackle to the anchor, pin through the chain where it belongs.

Two shackles do not provide superior articulation to 1 shackle and one chain link, surely?

And the probability of a shackle-specific failure, such as unscrewing, is doubled by using two of them, no?

[DoubleWhisky]

Originally Posted by Andrew Troup

The reason Peter S put a slot in the shank of the Rocna is to enable threading the eye of the shackle through the slot so you could fit the shackle to the anchor, pin through the chain where it belongs.

I think the slot in the shank is attribute of small size Rocnas only.
My 40 kg Rocna is slotless for sure

[Dockhead]

I would gladly use galvanized shackles, but the Wichard one linked by Pallaram above is the only one I have been able to find which is strong enough and yet will fit through even the enlarged link I have at the end of my 12mm chain.

According to Vyv Cox and other engineers, there is nothing wrong with stainless in ground tackle (but you should never use in a mooring system which is permanently under water). In fact, Vyv Cox uses the same Wichard shackle as I do.

[Andrew Troup]

Originally Posted by DoubleWhisky

I think the slot in the shank is attribute of small size Rocnas only.
My 40 kg Rocna is slotless for sure

Always had slots "back in my day"

[goboatingnow]

DONT forget not to "mouse" up the pin, with a bit of Monel wire

dave

[sparrowhawk1]

Originally Posted by sy_gilana

Please don't put a stainless shackle in between two galvanized items in an electrolyte.
If you don't know why not, please look it up.
The correct way to mount the correct shackle will be to put the pin through the last link of the chain, and it should touch the last link halfway around its circumference, to avoid a point load. The anchor should have a slot allowing the ear of the shackle through it.
Ideally a 5/8" shackle on a 1/2" chain. ie. one size up.

Agree 100 percent. Also agree with everything that JonJo said. If you put the pin to the anchor it increases the shear stress enormously putting most of the force on one side of the pin and as JonJo stated the weakest part of the shackle is the hole the pin goes through (on the shackle) . Also if stainless steel is deprived of oxygen it will be weakened and you may not even see any signs.

[JonJo]

[QUOTE=Dockhead;1528538]I would gladly use galvanized shackles, but the Wichard one linked by Pallaram above is the only one I have been able to find which is strong enough and yet will fit through even the enlarged link I have at the end of my 12mm chain.

Peerless, Crosby and Campbell (amongst others) make a 1/2 inch (pin size) alloy gal shackle with a WLL of 2.66t (I assume short tons) Proof Tested to 2 x WLL. The Peerless models have a 6:1 safety factor the Crosby ones a bit less (not sure about Campbell - but I guess similar). The ones you mention have a 4:1 safety factor.

These are conventional bow anchor shackles with narrow distance between eyes (as they are for lifting) and a lug with a hole in it for the pin. But check the shackle will actually fit your anchor! (not only the chain).

Each of the pins from the three manufacturers mentioned are slightly different, maybe enough that one or 2 might fit a specific chain but not the other.

edit The shackles are designated 7/16th inch (1/2 inch pin). Peerless' are in their Peer-Lift range and the Crosby shackles are their 209A range. Campbells are just in their High tensile range.

I suspect people like Gunnebo, Pewag and Rud might also make - but do not know. end edit

I think you are UK based so contact

wendy@tecni.eu

I've just bought smaller, 3/8th inch WLL 2t, gal Crosby shackles from the same range from Tecni for delivery to Oz. I think if you ask Tecni might actually measure the pin size so you can confirm it fits. I confess I do not know how you can get supply of the Peerless shackles (which seem better than the Crosby ones) and have them delivered economically (or sensibly) to the UK. I did try but no-one in America is interested in sticking anything in a padded envelope and sending US Post, they all seem to have vested interests in supporting expensive couriers

Good Luck

[DoubleWhisky]

Originally Posted by Andrew Troup

Always had slots "back in my day"

Sorry!!!!!!!!!!
I thought about this long one slot, similar to Manson Supreme!
My one is identical...
But... 115? I do not know this size Kilograms or pounds?

[Fuss]

Originally Posted by DoubleWhisky

Sorry!!!!!!!!!!
I thought about this long one slot, similar to Manson Supreme!
My one is identical...
But... 115? I do not know this size Kilograms or pounds?

The one in the picture is not 115 pounds.

It even looks heavier than 115kg but I guess it isn't because it has 115 written on it.

[noelex 77]

Did anyone notice that there appears to be an extra hole in the shank of the Rocna?

All the anchor manufacturers strongly discourage drilling a locating pin hole. I am surprised one would appear in what looks like a promotional photo.

[Cheechako]

Originally Posted by MarkJ

Hi Brian,

I don't think it matters. I got one shackle and can't for the foggiest visualise which way its up. No doubt some who "knows better" will give you the correct answer which will mean you have to spend $1,000 or buy a new boat... Or both!

Here's a crude drawing showing why it matters. Contact surfaces are much better one way.
However, I must say, I always use a big galvanized shackle at the anchor anyway then the SS one myself.

[sparrowhawk1]

Originally Posted by Cheechako

Here's a crude drawing showing why it matters. Contact surfaces are much better one way.
However, I must say, I always use a big galvanized shackle at the anchor anyway then the SS one myself.

That's for 100 percent straight pull which often does not happen at anchor. Nice drawing though.