Anchor question,

[noelex]

Quite correct - though there is no evidence you will ever need that extra capacity - so why carry it around.

Modern anchors are better than their predecessors, but I don't share your view of their infallibility. As you have pointed out, even small anchors can hold 2000 kg in the right circumstances, but in the real world the holding can, on occasions, be much less.

In post 63 of this thread I included some photos of a Kobra dragging. Here is another anchor, this time an Ultra. The anchor was slowly moving backwards. You can see from the puffs of sand sliding off the back of the fluke. The scope on this occasion was a shortish at 3:1, but some anchorages can only be utilised using these sort of scopes.

 

[NormanS]

Or sometimes anchor where the wind comes for all of the place.

Sorry, can't understand that one.

 

[GHA]

Sorry, can't understand that one.

Sorry, typo, *from* all over the place.
As happens sometimes, big gusts coming down off the hills from every direction, even a heavy long keeled boat gets pushed all over the place. Sometimes a really good snubber is essential to dampen the snatch loads, chain catenary really doesn't help much when you need it most.

 

[NormanS]

Sorry, typo, *from* all over the place.
As happens sometimes, big gusts coming down off the hills from every direction, even a heavy long keeled boat gets pushed all over the place. Sometimes a really good snubber is essential to dampen the snatch loads, chain catenary really doesn't help much when you need it most.

I take it that you've never thought of using an anchor sail?

 

[GHA]

I take it that you've never thought of using an anchor sail?

Doesn't help when the next big gust is 180 deg different from the last one. The boat still gets shoved around the anchorage.

I take it you've never sailed to islands where conditions like that can happen.

Like the Canaries for instance, Valle Gran Rey springs to mind.

 

[NormanS]

Doesn't help when the next big gust is 180 deg different from the last one. The boat still gets shoved around the anchorage.

I take it you've never sailed to islands where conditions like that can happen.

Like the Canaries for instance, Valle Gran Rey springs to mind.

I've told you where I anchor, and my thoughts and recommendations, are strictly only relevant for the conditions likely to be found there, and in similar situations. As I said previously, there are actions which can be taken to improve almost any situation, but if I was anchoring in a place where gusts were coming at 180°, I would at least consider lying to two anchors, possibly in a Bahamian Moor. Negativity never solves any problems.

 

[charles_reed]

What's the current thinking on the catenary effect?

most seem to agree that the catenary effect is of little use - probably more affected by seas than wind - and non-existent above Bf5 wind.

I have, for the past 10 years, included 3-10m of nylon Octoplait in my anchoring rode.
That has significantly reduced episodes of dragging.

I am convinced, though, that generalisations about anchoring tend to make fools of all of us, it is, after all a fairly complex system where bottom and boat are far more important than anchor or anchor-rode.
However the most important variable, IMHO, remains the anchorer's competence.

 

[charles_reed]

Showing my age - I recall in the distant past a credit card called Access. It had 2 memorable slogans, 'Access your flexible friend' and 'never leave home without it'. We think of our snubbers like that - though I may have attributed the wrong slogans to the short lived Access.

Jonathan

In fact, Jonathan, its ghost still exists.
The Access operation was taken over by the US Mastercard, who took over the Southend offices and still use the title "Access" in some of their products.
https://en.wikipedia.org/wiki/Access_(credit_card)

 

[JumbleDuck]

Sorry, typo, *from* all over the place.
As happens sometimes, big gusts coming down off the hills from every direction, even a heavy long keeled boat gets pushed all over the place.

Loch Scavaig is notorious for this.

 

[GHA]

Loch Scavaig is notorious for this.

Obviously no one can possibly "anchor properly" there then

 

[NormanS]

Obviously no one can possibly "anchor properly" there then

Funny you should say that. I've often used two anchors there.
It's a circular hole in the hill, almost surrounded by high cliffs, and tends to produce its own weather. No sea gets in, but a F6 SWly is liable to produce a F8 SEly within the anchorage. Sometimes with a NEly the wind just comes down vertically. There are times when it's really best avoided.

 

[JumbleDuck]

Obviously no one can possibly "anchor properly" there then

I've only been in there for one night, in fairly benign conditions, but I am told that there are indeed times when nobody can anchor there, even though it's completely sheltered from waves.

 

[Kelpie]

It's quite common for boats to be lying in opposite directions just a few boatlengths apart. Easterlies become westerlies as they bounce off the Cuillin ridge; southerlies are accelerated in fierce gusts around the base of Garbh Beinn; northerlies tumble down over the ridge as katabatic downdrafts.

The good news is that the holding is good, the anchorage shallow, the water clear (please, please don't set a tripping line- very inconsiderate and totally unnecessary)- and no swell ever gets in.

 

[Neeves]

In fact, Jonathan, its ghost still exists.
The Access operation was taken over by the US Mastercard, who took over the Southend offices and still use the title "Access" in some of their products.
https://en.wikipedia.org/wiki/Access_(credit_card)

Thanks Charles, I thought it was long dead and buried (and so deeply buried it never occurred to look in Wikipedia!).

 

[Neeves]

. All for the sake of a few more kilos on the bow.
Don't make no sense.

Did not quite understand this one - 'all for the sake of a few kgs on the bow' does this refer to chain or anchor. Because to make any difference to the anchor, one you will actually notice will need one at least twice the weight recommended. I doubt anyone will ever tell the difference between a 20kg anchor and a 25kg anchor. Once you double weight, then you will notice - and if you want twice the hold, think 3 times weight! - now that will start you thinking.

I agree with Charles - its all about decisions and skills of the owner - if you decide to anchor in a questionable bottom with an unreliable forecast then you can expect to be woken at 3am. If you anchor in weed with a roll bar anchor - you can expect it to clog - and then maybe drag with a tide or wind shift If you do not use a Fortress in thin mud then you can expect to drag - with virtually any other anchor (once you get to F5/6). Generalities can obviously never accommodate the specific, that once in a lifetime storm or the experience of the flighty multi vs the solid long keeler - and its easy to pick on the specific - even if its irrelevant for the majority.

NormanS - you mention your use of a riding sail, often - how would one make, use, a riding sail on a multi that has no back stay? The only 'idea' I have is to launch up the topping lift and have a little boom off the main boom, tensioned to each transom - does this sound sensible? Any idea of size vs yacht length. I'm assuming your riding sail if off the aft mast (or aft mast topping lift?) and you use the existing boom. You obviously are smitten - I've never, ever, seen one in use in Oz.

Jonathan

 

[GHA]

Did not quite understand this one - 'all for the sake of a few kgs on the bow' does this refer to chain or anchor.

Has anyone ever suggested double the anchor size?

Nope.

 

[Neeves]

Has anyone ever suggested double the anchor size?

Nope.

I think you need to look at Noelex anchor and read through Dashew. Both are strong proponents of grossly oversized anchors - Noelex has a whole thread devoted to the excellence of his choice. Most proponents of oversize reference Dashew to substantiate their philosophy.

Part of the philosophy is that very large anchors allow one to locate in areas with a very short scope even under arduous conditions - thus giving access to tight or crowded anchorages. Noelex makes the point, about short scopes, in one of his recent posts, above. This actually is of more critical importance for those with larger, longer yachts - and Dashew's motor yachts are now impressively big (as a tight anchorage to them is massive to most of us). I actually do not know of anyone, apart from Noelex and Dashew, who would consider anchoring on a single anchor at 3:1 (and less) in a tight anchorage if winds are going to be, even, 20 knots - let alone more. Though I really do not know many people that well and some of the people who say they follow this philosophy are hardly world girdling cruisers (better think the lotus eaters). But that does not stop the scare mongering - 'bigger is better'. Noelex says - buy an anchor as large as you can comfortably handle - our windlass would comfortably lift a 35kg anchor - why buy a 35kg anchor when we have had no problems with a 15kg steel anchor and now use a 8kg alloy anchor - in areas as challenging as Scotland's west coast (if that is considered challenging?!) The philosophy is persuasive and pervasive - it appeals to all of our fears, but is there any substance for 99.9% of us.

We might anchor at short scope, but invariably would use 2 anchors in a fork and if its that tight - we'ed be tying to a tree of rock as well!

But the bigger is better philosophy and the idea of grossly oversized anchors is repetitively advocated often without mention this is really relevant only if you are thinking of anchoring on that single anchor on a very short scope in winds over F6.

I confess to have no experience of anchoring at 3:1 let alone 2:1 with any anchor in winds over 35 knots (in fact even for lunch we would use 5:1) - so I simply cannot comment on whether any of Dashew's philosophy is correct. I doubt if many of the proponents have any experience either. We would be on 7:1, 2 rodes and maybe tied to a tree or rock - we like belt and braces and I think Norman suggests, appropriate to his yacht, the same cautious approach. We have never found ourselves where this is not possible though last time we found ourselves in the path of a 70 knot storm we did need to travel 20nm.

Another part of the philosophy is that a larger anchor will develop more hold in difficult substrates. To me this is very questionable - it goes back to my example of the nail and garden spade. A different design might offer better hold but I have seen no evidence that a bigger anchor of the same design is any 'safer' than a smaller one. If you can only bury 100 cmsq of fluke it does not matter if it is big or small - the hold will be the same. For me - better a different anchor that might handle the seabed more appropriately - than put all our eggs in one anchor.

It is impossible to dismiss Dashew's comments - he has been there and done that. Its his disciples that have the passion - his comments tend to be much less dogmatic.

But yes - there are advocates.

Jonathan

 

[Duster]

Neeves' comments, loosely summerised ( sorry ) as 'one size does not fit all', remind me of anchoring in the daunting Loch Scavaig, in a mountain cauldron where the swirling downdraughts off the close-by 3000' Cuillin Ridge frequently lift the surface of the water in spiralling sheets of spray. Sustained and repeated gusts in excess of 60mph are not uncommon, even in summer, and a Dragonfly ( catamaran - no! ) trimaran was inverted there - with no sail up.

I've anchored in there in two boats - one a Catapult cat-dinghy..... which was pulled up onto the 'boilerplate' slabs and tied down to steel pegs in the rock.... and in a Rival 34, which was anchored AND tied into a 3-way set of lines secured to pegs in the rocks. This is commonplace in Scandinavia and, to a lesser degree, among those hardy Scots who use the little-visited nooks of the Outer Isles. No trees! Carrying a hammer and some pegs - with some long lines - is a cheap option compared with the cost of another UHHP anchor. A certain Skip Novak shows this practice in one of YW's excellent videos, free to watch from a corner of this website.

 

[JumbleDuck]

I think you need to look at Noelex anchor and read through Dashew. Both are strong proponents of grossly oversized anchors

But, and with all due respect, you start about a thread a week in order to tell us we all need to have much more effective anchors. To those of us coping quite happily with a 25 lb CQR, a 15 lb Rocna is grossly oversized.

Luckily my anchor does not read these threads and so continue, obliviously, to work.

 

[Neeves]

But, and with all due respect, you start about a thread a week in order to tell us we all need to have much more effective anchors. To those of us coping quite happily with a 25 lb CQR, a 15 lb Rocna is grossly oversized.

Luckily my anchor does not read these threads and so continue, obliviously, to work.

I thought I'd answered this but must have deleted my comment!

You exaggerate.

I had a thread on Knox Anchor in March 2013 and then a lapse of activity till Sept 2015 since when I have had 4 threads (on anchoring)

Dragging of Anchors (this was to evaluate whether modern anchors dragged)
Snubbers and Chain Hooks
Stainless Steel Anchor Chain (this was to question whether people had any experience of duplex chain)
Anchor attachments. (this was primarily about shackles)

I think that works out at one per month.

On each of these threads you have been a constant attendee, making posts - so though your anchor takes no notice, you do and I, for one. value your comment.

My conclusion is either you are very bored or you find these threads interesting

Jonathan