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How much scope on yer anchor?


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How much chain/warp would you expect to be about right for this area?

I dropped all the chain out of my locker today to see what I actually had, and have got 30m of chain, which was bolted hard and fast to the boat.

I would have thought this wasn't really enough, so I intend to get some warp spliced onto it. What size warp (I've heard nylon is best as it sinks and is stretchy) and what sort of length should I be thinking of?

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Another 30m of 12mm Anchorplait should be nice and run through the gypsy too, make sure it’s spliced INTO the chain rather than a simple splice loop to a shackle or the final link or it will not negotiate the gypsy well.

For most inshore anchoring your current scope is enough though it should never be fixed to the boat without a couple of feet of rode that can be quickly cut if needs be. The extra rode will allow you to anchor in a bit more water and can be pressed into service as an emergency tow line if needs be. Stretch is not really needed (though can't hurt) as with 30m of chain out you will have all the shock resistance you need.

http://www.jimmygreen.co.uk/technical_info/anchorplait_splicing_guide.htm

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Like most splicing, not near as complex as it looks Mark, if you have a bit of a google you may even find a video. Mind you, if it's done by somebody who does it every day it will likely be prettier if no stronger.

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where are you thinking of dropping the hook Mark? i have 30m of chain which is sufficient for 10m of water. If you are in more than that then you are not likely to need to anchor unless you feel the need to make everyone sick on a fishing trip.

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We're not really planning it at the moment, but eldest son is keen to try a spot of fishing for something he can eat. From what I've read, 30m chain in 10m of water seems barely enough? The RYA recommend 4x depth for chain only and 6x for chain/warp. I had assumed for emergency type deployment that about 60m total (as David has also mentioned) would be about the right amount.

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3X is fine for a lunch stop or fishing (even then for fishing you sometimes need more for accurate positioning over a mark) in calm conditions, anything else and you need more, especially if the holding is poor. Anchor scope is another of those things you need to have more of than just what you expect to need and hope to never use it.

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well it may have changed since I did day skipper but the RYA were saying 3 times for chain and 5 times for 10m chain plus rope then.

don't think I would want to anchor Clanny for fishing in anything other than flat calm, full planing hulls are not that comfortable in any sort of swell and chop if you tie them to the bottom, obviously not a sea fisherman but think I would rather take my chances drifting over a mark to make things a bit less rolly.

Same would be true if I was trying to fix something on the boat if I was in more than 10m of water

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As you say Ian, you're clearly not a sea angler if you think drift fishing is less rolly than anchoring, as that puts you beam on. :naughty: :naughty:

What the RYA recommend is based on minimums in my experience as most cruisers (sail or power) hardly ever anchor at all. Remember this, when you run out, you run out.

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well it may have changed since I did day skipper but the RYA were saying 3 times for chain and 5 times for 10m chain plus rope then.

I can only assume they have revised their recommendations Ian. The scopes I mentioned above are from the RYA Powerboating Handbook I bought at LIBS. I was a bit surprised, as I thought it was 3x for chain too!

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Ginger biscuits that,s what you need for drift fishing......Sue used to take a packet when we used to drift along the Fairway mark off Wells for 4 miles at a time,it takes some getting used to,just keep watching the rod tip that helps aswell.If you want to sample it just put her in neutral if we get out at easter! :bow

ps take a bucket!

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Ginger biscuits that,s what you need for drift fishing......Sue used to take a packet when we used to drift along the Fairway mark off Wells for 4 miles at a time,it takes some getting used to,just keep watching the rod tip that helps aswell.If you want to sample it just put her in neutral if we get out at easter! :bow

ps take a bucket!

Whilst you're at it you can mix up the rubby dubby for a shark fishing drift.

Ginger works for SWMBO too, also quite good for general nausia at any time.

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ok, so today, I went to Norfolk Marine with my anchor chain (christ, that's heavy!). They are going to splice me on 30m of 12mm 8 strand with a thimble the other end cheaper that I could have bought the rope from Jimmy Green and tried to splice it myself. Just one to bear in mind :wave

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Not sure I agree with some of this but the scope seems right.

Anchored while fishing unless flat calm is never comfortable which is why some fish and some don't 1.gif

Anchor Rodes

by Alain Hylas (Inventor of the 'Spade' anchor)

NB - these are Alain's opinions, and as with all advice you must eventually make up your own mind. He does do a lot of anchoring though!

CHAIN OR ROPE?

The main and ONLY advantage of the chain is that it is the only and perfect mean to avoid chafing of the anchoring rode on aggressive sea beds...

Except for this point, chain has all the disadvantages..:

Stored in the bow chain locker, it adds a heavy weight in the last place you want one. When deployed, chain is actually working in the the opposite way to the way it should work:

* with light wind, it gives a perfect horizontal pull to the anchor and the best holding.

* with moderate wind, its weight and catenary effect give a perfect shock absorbing effect.

* As the wind builds up, the chain will become straighter (and this with as little as 25/30 knots of wind). The pulling angle will increase and as a consequence, the holding of the anchor will decrease.

* When the shock absorbing effect is most necessary, the "bar tight" chain will not allow this to happen.

If there are waves entering the anchorage, the resulting shocks will be then directly transferred to the anchor, which then has more chance to break free .. . and more seriously, the chain is subject to high "peaks" of pulling force and has a consequently higher risk of breaking..

WHAT LENGTH OF CHAIN?

During the last seven and half months, I spent 129 days anchored (out of 228) in 61 different anchorages. The mean water depth was 6.50 metres and the scope 5/1. The total lenght of the mooring line was about 30 meters, of which 23.5 metres was lying on the bottom (30 - 6.50 m) Therefore, I believe a length of about 25 meters is perfect. If the water height is less, then you will be anchoring with an all chain line .. . if the wind build up, you can pay out more scope but the wind will push the boat and the rope line will not chafe on the bottom.

WHAT LENGTH OF ANCHORING RODE?

Holding is in direct relation to the pulling length of the rode .. . (or more accurately, the pulling angle). Generally speaking, with a scope of 4/1 you will have about 55 % of the maximum holding of the anchor, with a scope of 6/1 about 70 % with a scope of 8/1: 80 % and with 10/1 about 85 % the maximum. - 100 % holding will be achieved with a horizontal rode or a "Infinite/1 scope.

Increasing the scope will be efficient up to 10/1 - With more than 10/1, a large increase in the scope will give only a negligible increase in holding. Therefore, the total length of the rode has to be adapted in relation with the conditions you are expecting to meet, and should be about ten times the maximum d epth you expect have to anchor in. (I suggest 100 meters).

WHAT ROPE TO USE WITH THE CHAIN?

Natural fibers are no longer used .Of the artificial fibers, the one which has the best elasticity (shock absorbing effect) is polyamide (Nylon, Perlon, Enkalon). As the breaking strenght of 10 mm chain is 5 tons, a 16 mm polyamide line will be well suited. (Breaking strain 5.6 tons). Don't oversize the rope. Yes, you will increase the strength, but at the same time you will decrease the elasticity . . . and "elasticity" is the secret.

You have the choice of three strand rope or eight strand rope (also called "square line"). Eight strands rope is better.

CONNECTING ROPE TO CHAIN

Remember: A CHAIN HAS THE RESISTANCE OF ITS WEAKEST LINK...

a) With an "eye" splice over a thimble and then a shackle on the chain.

ALWAYS use a shackle one size bigger than the chain.. and secure the pin with a monel wire. This is a perfectly safe solution but the eye splice will have difficulties to go throuh the bow roller.. will no pass the windlass gipsy and will never go through the deck pipe...

B) with a rope to chain splice.. There are two ways to do this: the wrong one and the right one.

Wrong: NEVER splice the rope over the rope after a "U" turn into the last chain link . . . you will lose about half of the strength of the rope.

Right: Make a direct rope to chain splice. This is quite easy to do.. when you know how!!! (We hope to publish Alain's detailed description of this in the future - ed)

FINAL OBSERVATIONS:

Last point, I'm currently in the LAS PALMAS (Canaria) harbor covering the A.R.C. event. (Nov 2002). Curiosity prompted me to check the rodes of these boats, which will cross the ocean and spend plenty of time anchored in the Caribbean. I was alarmed to realise than more than half the boats are relying on what is in my opinion a dangerous rode. (Note - I am not talking about inadequate anchors here).

Main points are:

A too small, rusted and not secured shackle

The use of beautiful stainless steel anchor connectors. The most common one has an axe drilled to put a "security " screw on the opposite side.. although this is a wonderful idea to avoid unscrewing of the axe. the hole in the middle of the axe decreases the strenght. For a 5 tons chain resistance, this connector has only three tons of resistance ... check yours!!!.

Swivels . . . the theory is perfect, but under load, swivels don't work. More importantly, check their breaking strength, not only with a straight pull but also with a sideways pull..

Connecting links - these have a breaking strength of only few hundred kg . . . NEVER use them on a mooring line.

CONNECTING THE ANCHOR AND CHAIN

A shackle is perfect. As before, always use one size bigger than the chain . . .and secure the pin! The simplest and perfect way is to use a toggle, the same you use for your rigging. Again, use one size bigger than the chain (12 mm for 10 mm chain).

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One thing I forgot to mention is that I assume most of the broads based boats will already carry a very serviceable angel in the form of a mudweight. If you find holding a bit difficult then you can run it down your rode on a snap shackle or similar which has the effect of bringing the rode more parallel to the seabed and helping the hook hold a bit better. It’s something that can give you a bit extra peace of mind if anchoring in deepish (for the East Coast) water overnight.

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That's something else I need to get around to buying :roll: The mudweight that came with the boat appears to be made from resin poured around blocks of lead or stone, and weighs bugger all. I can pick it up with just a finger and thumb, so the chances of it having any effect regarding boat holding on the broads are negligible. I'd have more luck tying a rope around one if the kids and throwing them in (though I believe this practise is frowned upon these days).

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