Using a ball weight on the anchor chain

[Uncle Bob]

Originally Posted by Ballsnall

Also a very system when used on cyclone mooring although the Kellet is quite a bit heavier. Don't underestimate the benefit of the shock absorbing capacity.

Never actually used one in those circumstances have you?

[ilCigno]

Originally Posted by StuM

Good analyisis:
https://www.petersmith.net.nz/boat-anchors/kellets.php

QED
Better to buy a somewhat longer chain and/or a heavier anchor.

[thinwater]

Pretty funny.


a. I'm willing to bet that 80% of the responders have never used a kellet.


b. With all chain (my last boat) I'm in the no-kellet camp for the obvious reasons; it is far more user friendly to let out another 10-20 feet of chain.



c. With rope rode (current boat) the story is reversed. A kellet is one of the handiest things, primarily for keeping the rope away from the keel during tide changes and to make your boat swing like all-chain.


d. But I would not use a metal ball. I keep a length of chain, which make into loops and attach to the rode with a prusik sling. The chain is the same weight and benefit as a ball, but it is flexible and I can deploy/recover it over the roller with the anchor, and leave it on the chain in the locker, making it no trouble at all to use.


e. The optimum position depends on the purpose. Closer to the anchor for security, centered for swing control, and closer to the boat to keep the rode off the keel.

[boat driver]

Originally Posted by RaymondR

Why carry around a big chunk of metal of limited use when you can carry a second (or third or fourth) anchor and seventy five yards of nylon rode to provide the security of redundancy?

totally agree-
a second anchor on short scope works very well in a storm- and in a crowded anchorage. But more important in a crowded anchorage, scope on surrounding vessels and type of anchor rodes is even more important. Put a rope next to chain and thereby having two different swings.

More important is 1) communication between anchored boats (aka harbormasters position) 2) Being sure the anchor stays in position it was set, not dragging. If worried about anchor holding, get a bigger anchor.

[RaymondR]

If you have plenty of chain you can fold and treble a section using shackles and thereby considerably increase the horizontal restoring force component of the catenary.

[s/v Jedi]

Originally Posted by RaymondR

If you have plenty of chain you can fold and treble a section using shackles and thereby considerably increase the horizontal restoring force component of the catenary.

Shackles don’t really fit, but small dyneema does. Spyderline is good for that as it holds knots (lashing) really well.

[MathiasW]

Originally Posted by thinwater

Pretty funny.


a. I'm willing to bet that 80% of the responders have never used a kellet.


b. With all chain (my last boat) I'm in the no-kellet camp for the obvious reasons; it is far more user friendly to let out another 10-20 feet of chain.



c. With rope rode (current boat) the story is reversed. A kellet is one of the handiest things, primarily for keeping the rope away from the keel during tide changes and to make your boat swing like all-chain.


d. But I would not use a metal ball. I keep a length of chain, which make into loops and attach to the rode with a prusik sling. The chain is the same weight and benefit as a ball, but it is flexible and I can deploy/recover it over the roller with the anchor, and leave it on the chain in the locker, making it no trouble at all to use.


e. The optimum position depends on the purpose. Closer to the anchor for security, centered for swing control, and closer to the boat to keep the rode off the keel.

Yep, have to agree on this!

I am in the 80% camp. Mostly, because I am all chain anyway, but also, because I have been in a number of occasions where I would have dreaded to have to go to the bow and lift/detach a kellet in a hurry and under a lot of stress. Eg, when another vessel is slowly drifting towards you and you try to make an escape...

As others have said already. For reducing the swinging radius and keeping the angle at the anchor small, the kellet should be as close to the anchor as possible, whilst still being off the seabed, to have the best effect. If you want to get the most out of the kellet in terms of temporary energy storage / damping, then it needs to be placed at a position along the chain that has the largest vertical swing in a surge, which is usually somewhere half way.

BUT: The effects are smallish. Placed close to the anchor, one can show mathematically that the kellet is at best equivalent to a chain of the same amount of weight (in water). For a 10 mm chain, 10 kp / kg are therefore less than 5 metres chain equivalent, which will matter only in a crowded space. Same goes for energy absorption. Again, it will fare not better than a chain segment inserted at its place of the same weight. If you use a chain of 80 metres length, then adding another 5 metres does not change its energy storage capabilities at all. So, it is hard to underestimate the energy storage capabilities of a kellet, really, unless you are using very little chain to begin with.

I can see the advantage of sorting out ropes and somewhat reducing swinging radius in a crowded space, when it is not too windy. But in a storm, no, no way. A kellet immobilises me...

Cheers, Mathias

PS: My long essay on anchor chains, when they work and when they don't... Now also covering a mix of rope and chain (In English): https://trimaran-san.de/die-kettenku...atiker-ankert/

[MathiasW]

Originally Posted by ilCigno

Fairly useless indeed. In strong winds the anchor chain (or rode, doesn't matter) is completely taut, no kellett / sentinel / angel with any practical weight will change that. If you want to improve your storm anchoring tactics, increase the scope (i.e. longer rope or chain).

If that happens and you are using only chain and do not use a decent snubber / bridle - then you are simply anchoring in too shallow water.

In deeper water, a catenary will always form. If it does not make sense to go there, then use a decent snubber/bridle that can stretch by more than a metre in strong wind. That will give you the dampening you need. Remember that a chain does not work well in shallow water. It needs very elastic snubber / bridle or rope to add the missing energy absorbing capability.

Thus: Your advice to use more scope in shallow water is not going to help you, if you are on all chain with no nylon elasticity.

Cheers, Mathias

Anchor Chain Calculator

[thinwater]

Re. kellets vs. swing with rope rode. This is only important in light winds, when a boat on chain may barely lift the chain and barely swing, but boats on rope move a lot. In a crowded anchorage this can cause conflicts and a kellet solves the problem. Once the wind picks up to over about 15 knots, they all swing the same anyway--straight back.


Additionally, boats with rope rodes typically (and should) use slightly greater scope, resulting in greater swing if they do not use a kellet in light winds. If you are on all-chain, expect it.


It's tempting to estimate the scope of other boats by the angle of the rode leaving the bow, but that only works in very strong winds. In lighter winds the angle stays near 35 degrees through a wide range in scope.



But no, with chain just a little more chain is better. If the anchorage is so crowded that 10 feet of chain is a problem, consider that 10 feet of dragging is the same problem. One way or the other, you are rolling the dice on your set and the weather. I'm glad it's not that crowed here.

[mrcarson]

Over the yrs I've tried a few different things. don't have a chain weight.
Nowadays.
32 ft boat (steel) 35lb CQR anchor with 40/50ft of heavier link chain on primary chain to anchor. With a large Admiralty and 40ft of chain/link ready to clip onto primary anchor head. if unknown ground or heavy weather. ALL chain.
Port side pick is Bruce copy with 40 ft chain and 110m of 1in Nylon for short term or dual pick set.
30lb Danforth type on stern rail. 10ft chain and a 100m length of 1in Silver for use as a brake./Swing retarder.
Spare chain and Bruce in bilges above lead as ballast. (chain strapped down)
Ca/have also used the 3 anchors on short chains. on a large swivel/ring to set as a 3 way mooring when leaving boat for a while.

[nmccubbin]

Your anchor seems very small to me, so the system needs all the help you can give it.
Lots of scope, 6:1 or more
A LONg nylon snubber, no more than 5/8 diameter Three strand. Ideally half the length of the ride.
It is well supported by mathematics, my first hand experience in a category 4 hurricane & other storms, and by others posters that all-chain roses are dead rigid in a real blow (say 40 plus sustained) That will either break the chain or sledge-hammer the anchor out.
Make sure the rope going over the bow roller is well protected against chafe

[NPCampbell]

If my math is correct ...

Given a 100 foot, horizontal, weightless line, for every 100 pounds of tension put on the line, it takes 3.5 pounds of kellet weight at the midpoint to deflect the line 1 degree.

In water, buoyancy would reduce the weight of iron so it would require 6 pounds of kellet weight vs 3.5 pounds to achieve the same result.

A 15 knot wind on a 25' boat should generate more than 100 pounds of force on an anchor line.

So yes, kellets mathematically work, but the weight required to be useful is pretty high.

[sv Stella Maris]

Finally, thanks ! I have an old anchoring guide that calls them a “kedge”. I have played with multiple. The same people that think chain is taught (straight) in a storm are the same that have succumbed to tiny chain and short scopes to accommodate affordable electric windlasses (which is not a bad position for the average sailor).

BUT, days of old and sailors not willing to let “calculations” dictate them dragging or not used lots of both weight and scope.

I have a modern anchor, it sets amazingly. I have “large” chain, and a bigger windlass. I put out ample scope for expectant weather, and dive my anchor during storms. I have never seen my chain anywhere near straight…physics disallows it.

Kellets are cool. Anchor, get in the water. Don’t be afraid of close boat that can and may go bump in the night (I’m near the French often, hehe).

Good topic.

[StuM]

taut = straight.
taught = what you got from a teacher.

[RaymondR]

Originally Posted by StuM

taut = straight.
taught = what you got from a teacher.

And "tort" is what lawyers do to you??