Can an anchor be too big?

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Coaster

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Within reason, of course - I don't mean something completely ridiculous, such as a 400lb Manson on a Mirror dinghy.

I appreciate that there might just be more than one opinion about anchor types but I'm not asking about that. What I would like to know is what disadvantages there are in going up a size or two on the recommended weight for a particular boat.

Initial thoughts that occur to me include additional weight forward if stowed at the stemhead, the extra weight to haul up, and possibly a harder job to break out if well dug in.
 
No issues with going up one size to provide a sense of extra safety, but size means extra handling, breakout, storage and cost considerations.

Going up two sizes would not be pragmatic and might make deployment and recovery more difficult; choosing a modern technical design might mean you could even go smaller.
 
might be worth upping the chain size rather than the anchor? or both...

we have 8mm chain on a 3ton boat, and rarely does the chain reset with tide or light winds etc. and rarely drags in gales etc always a bonus
 
An anchor's capacity to take maximum load is, I've always understood, directly related to the volume of material 'hooked' by its flukes/blade. So a big one can be expected to do rather better than a tiddler. And the heavier it is, the more readily will it set and perhaps reset in a bottom that is overgrown.

I was taught the right anchor to carry is the biggest one you can manhandle on the foredeck.

There are lots of leisure sailors who rue the day they were persuaded to make do with an inadequate anchor. And anchoring securely is a skill - the more you do, and then think about it, the better you get.

At some stage in your sailing career, you may be committing the lives of your family and friends to that anchoring gear. And you won't get to choose when.....

:)
 
Oversized anchor gives you excess weight in the end of the boat, and also high up, just where you don't want it. This is especially critical in a small boat, where the contribution to hobby-horsing (nautical term escapes me for the moment) can be very noticeable.


Ooops. Distracted mid sentence for an hour or so, and Gardenshed has got in beforehand with same point.
 
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Why can't yacht designers cut out alll this anchor stuff and just fit a decent handbrake?
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Could do what the mobos do. Just leave the engine in gear.

based on some of the antics in busy solent anchorages I'm sure some try just that! :D
 
Coaster said:
Within reason, of course - I don't mean something completely ridiculous, such as a 400lb Manson on a Mirror dinghy.

I appreciate that there might just be more than one opinion about anchor types but I'm not asking about that. What I would like to know is what disadvantages there are in going up a size or two on the recommended weight for a particular boat.

Initial thoughts that occur to me include additional weight forward if stowed at the stemhead, the extra weight to haul up, and possibly a harder job to break out if well dug in.
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One of the things that is never heard after a storm is forcast when you are at anchor.

" Our anchor is too large, we need to get a smaller one."
 
Thanks for the replies.

LittleSister said:
...especially critical in a small boat...
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I wonder what qualifies as a small boat? Ours is a 34' fin keeled sailing boat and displaces about 8 tons.

So far as extra weight forward is concerned I'm not convinced that an additional say 10kg will make much difference. A reasonable length of chain will be much heavier than the anchor, e.g. 50m of 8mm short link weighs about 70kg. Going up to 75m of 9.5mm increases the chain weight to 150kg.

TQA's comment regarding the aftermath of a storm, i.e. that no-one ever complains their anchor was too large, strikes me as particularly valid.

Being more specific, I'm thinking of getting a 20kg anchor of modern design. The various manufacturers generally recommend an anchor in the 10kg to 15kg range. The benefits of a 20kg hook seem to greatly outweigh (forgive the pun) any disadvantages, especially for anyone spending nights at anchor.
 
A heavier anchor inspires a bit more confidence, but you need to think how you'll handle it and retrieve it- tripping line needed? Enough crew to deal with it?
There's also the question of what sort of anchoring you do - and anchor type. We use a Bruce -and that works pretty well in most circumstances. We have a secondary 10kG Danforth in another locker -never used it yet.

The last anchor I saw on deck last week was a 6Ton Bruce, and the "small" Danforths occasionally used on offshore rigs are just 10Tons ;-). Bruce anchors hold us down west of Shetland over the winter, so I'm quite happy to have them on our yacht (35ft)
Go a little large - but don't over-do it.

regards, Graeme
 
Bigger is not necessarily heavier....

Don’t confuse weight and Holding characteristics…

Bilbobaggins is perfectly right when saying:

An anchor's capacity to take maximum load is, directly related to the volume of material 'hooked' by its flukes/blade.
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Larger the fluke = bigger the holding.

But fluke surface area doesn’t necessarily mean weight, it would be interesting to compare the overall anchor weight and the blade surface area – Unfortunately, very few anchor manufacturers give info about the surface area of their anchor.

Just a few examples:
- a 30 kg SPADE anchor has a blade surface area of 1400 sq cm
- a 30 kg Rocna has a blade surface area of 1590 sq cm
- a 30 kg RAYA has a blade surface area of 2000 sq cm or 30% more surface area than the Spade anchor

Then you can have a bigger anchor without increasing weight at the bow...

João
 
bilbobaggins said:
An anchor's capacity to take maximum load is, I've always understood, directly related to the volume of material 'hooked' by its flukes/blade. So a big one can be expected to do rather better than a tiddler.
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In the distant days when the Fortress was The Anchor To Have, according to all the magazines, various tests were produced showing that weight for weight it did much better than a Danforth. But it was aluminium alloy, so much lighter ... if you compared them size for size, the holding powers were very close. The answer was clear: replace a 20kg Danforth with a 20kg Fortress and get much more holding power for the same ease of handling. Unfortunately, the Fortress seemed to be priced by size, not weight, so that logical option was horribly expensive.
 
bilbobaggins said:
An anchor's capacity to take maximum load is, I've always understood, directly related to the volume of material 'hooked' by its flukes/blade. So a big one can be expected to do rather better than a tiddler. And the heavier it is, the more readily will it set and perhaps reset in a bottom that is overgrown.

I was taught the right anchor to carry is the biggest one you can manhandle on the foredeck.

There are lots of leisure sailors who rue the day they were persuaded to make do with an inadequate anchor. And anchoring securely is a skill - the more you do, and then think about it, the better you get.

At some stage in your sailing career, you may be committing the lives of your family and friends to that anchoring gear. And you won't get to choose when.....

:)
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Seconded.

The pitiful excuses for anchors seen on many boats make me worry about the owners and if they ever used them. It seems the more modern and excuse me for mentioning them - but Mobos particularly often lack a decent anchor of good amount of kg's.

We read posts about handling and SWMBO cannot lift it ... etc. Sorry but anchoring if by hand is a mans job - cause the anchor should be heavy enough to do it's job. Settling for a lightweight for SWMBO to handle is IMHO totally wrong..... unless she's a Shotput champion or girt big wrestler lass !!
 
We read posts about handling and SWMBO cannot lift it ... etc. Sorry but anchoring if by hand is a mans job - cause the anchor should be heavy enough to do it's job. Settling for a lightweight for SWMBO to handle is IMHO totally wrong..... unless she's a Shotput champion or girt big wrestler lass !!
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That sort of fits with my thinking. Peeps doing what they're best capable of, or 'horses for courses'!

The big heavy 'carthorse' should be up the front, hauling the heavy metal around the foredeck. The 'pretty little filly' should be down the back, positioning the whole kit 'n caboodle, and making the decisions... ;)
 
The big heavy 'carthorse' should be up the front, hauling the heavy metal around the foredeck. The 'pretty little filly' should be down the back, positioning the whole kit 'n caboodle, and making the decisions... ;)
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My thinking also, SWMBO mandles the back end when anchoring, picking up mooring buoys etc, I have longer stronger arms so makes sense to us.

I have too often seen the "pretty filly" on the foredeck trying to pick up a mooring buoy she can't reach being yelled at by the "carthorse" in the cockpit
 
Refueler said:
We read posts about handling and SWMBO cannot lift it ... etc. Sorry but anchoring if by hand is a mans job - cause the anchor should be heavy enough to do it's job. Settling for a lightweight for SWMBO to handle is IMHO totally wrong..... unless she's a Shotput champion or girt big wrestler lass !!
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I think it is very unwise to have any safety-critical system or equipment which can't be operated by everyone. What's going to happen with your Big Butch Anchor when it's night, blowing a hooley and you're down below, sweating out a broken leg?
 
orbister said:
I think it is very unwise to have any safety-critical system or equipment which can't be operated by everyone. What's going to happen with your Big Butch Anchor when it's night, blowing a hooley and you're down below, sweating out a broken leg?
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If the anchor is up to the job boat will stay put; if its light enough for light weight crew to recover in those circumstances you may all be dragging out to sea or up the beach.

I have on three occasions over the last 30 years been anchored in UK waters when the boat's anemometer stayed hard against the 60 knot stop for a number of hours and mean wind speeds reached into the 70's or 80's (shore records checked after the events). On the first occasion I was not on board and the boat went up the beach. On the other two occasions I had anchored in 'normal' conditions so was pleased that my main anchor was regarded by many as seriously overweight. I deployed the second anchor - also overweight by most standards, and ran the engine in gear at a fast tick over to take some of the load off the ground tackle, and survived without damage.

No, on a cruising boat an anchor can not be too big - but does need suitable chain and a sensible manual windlass for recovery (have come across too many failed electric windlasses to take them seriously) and roller for stowing.

Have just purchased a Rocna for my new boat - recommended size for winds up to 50 knots is 20 kg so I fitted the 25 kg.
 
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