Correct size of anchor - new gen against old

[smeaks]

Following the recent discussion on new style and old style anchors is there an advantage in the new generation anchors in that you can carry a smaller anchor? What size manson/rocona type would I need to comfortably secure a 27ft yacht?

 

[Pye_End]

I guess to some extent the question as to to what size anchor you need depends on what sort of anchoring you do, and in what conditions.

Mine is a 10Kg (new gen) for a 26 foot, which has been fine. If you anchored in the wilds of Scotland in the middle of the winter you probably want to err on the larger side. If you just anchor in good weather, with good holding, and usually don't leave the boat by herself for too long then you may well get away with something smaller (ignoring for a minute of what you would do in an emergancy).

 

[maxi]

What size anchor

The new edition of Sailing Today has an extremely interesting article and comparison testing of old versus new, with quantified outcomes which are not what I expected.

Does not give a table of suitable anchor sizes for any particular size of boat, but it's not hard to extrapolate form their data.

 

[jason -and the arguenauts]

The holding power of any anchor is very variable cos it depends on what the bottom is and how well the anchor digs in. But once dug in, the holding power is more a function of anchor area than shape. So my inclination would be to use the smaller modern anchor but to make sure I had a second one to deploy should the sh*t hit the fan.

I'm a fan of the Fortress since that combines low weight with large area. But like all Danforths it has the problem of rocks jamming the flukes and possible failure to re set.

Dont like the "new generation" bit since it implies that things have radically changed. Like NuLabour did and look where that got us. In other words I dont believe that the current crop of wonder anchors are really so much better than the old ones that I would rush to the shops to buy one.

 

[craigsmith]

Following the recent discussion on new style and old style anchors is there an advantage in the new generation anchors in that you can carry a smaller anchor? What size manson/rocona type would I need to comfortably secure a 27ft yacht?

Yes, the newer anchors are substantially more efficient and allow either far greater performance/security on a weight-for-weight basis, or a smaller anchor to be carried (less weight/cost).

All manufacturers/brands do "sizing" differently so you mustn't compare the different recommendations. For Rocna's part, read this:
www.rocna.com/kb/Rocna_sizing_recommendations

 

[Quandary]

Anchors again?

You are a brave man starting this theme again.
If you are talking about roll bar anchors recovery and stowage is a big issue to consider. You don't want an arrangement that put you off the whole idea of anchoring frequently and many of us even in the Wild West anchor regularly but still manage to avoid open bays in anything over force 5-6. I dont like an anchor hanging over the front and insist on using my anchor locker. After extensive handling tests I concluded that a 15 kg. Manson or Rocna with roll bar on 8mm chain was just too awkward to manhandle regularly through the pulpit rails and also risked increased banging on my fairly plumb bow , in the end I bought a 11Kg Manson.
I notice that in a similar question in the 'improved' YM an 'expert' advises changing to 10 or 12 mm chain for a boat of your size, he however did not risk adressing the type of anchor, most boats of this size come with 8mm. chain which in my experience is pefectly adequate and much easier to handle. I would suggest that unless you envisage heavy weather open water anchoring 10 kg. is ok, if you do ever get caught out your second anchor can be used to supplement it. Just make sure to set it properly.
Weight when and where stowed is also a consideration if you like to sail efficently
There will shortly be advice from Brazil on going much lighter.

 

[smeaks]

thanks.. just what i wanted.

 

[jason -and the arguenauts]

Yes, the newer anchors are substantially more efficient and allow either far greater performance/security on a weight-for-weight basis, or a smaller anchor to be carried (less weight/cost).

Can you explain why (say) a 2 square foot cross section blade on a Rocna would hold any better than the same cross section on a Danforth?

I accept that digging in might be different because of different design but I would have thought that once diug in, resistance to drag would depend on cross section except possibly for plough types.

 

[craigsmith]

Because of the fluke shape (concave), specific profile, better burying capability reaching into harder substrates, weight balance / fluke-to-shank configuration, etc.

 

[Quandary]

Digging in

I think that the speed and certainty of digging in is key, also the certainty of remaining dug in or re-setting with a tide change. My experience is that clean mud or sand is usually ok with most anchors but gravelly or stony bottoms can worry me, kelp which is everywhere here can be hard to avoid, (in Canna for instance you can hunt about and still not find a decent area of clean bottom and the kelp is brushing your bottom), I expect my main anchor to be able to cope with these. Over the years on different boats I have used a fisherman, CQR, Bruce, Delta and now Manson in different combinations, the boats (and anchors) size, weight and windage has varied but I am convinced that each was a significant improvement on its predecessor. (Though I would still like to be able to carry a fisherman just for stony bottoms.) The most heavy was a 22kg Bruce which I still have but no longer carry because of it awkwardness when recovering, I carry a 11 kg Manson and a 10kg. Delta, the Delta is the kedge but it is by far my favourite anchor for appearance and handling and I hope that over time I can promote it back to the front, time will tell. I have always avoided clones though one would expect Bainbridge/Lewmar to make a good copy of the Bruce. I am still just about fit enough to recover by hand, I have had hand and powered windlasses on bigger boats but now I prefer a decent pair of gloves. Obviously if you are happy with the anchor in the roller and a powered windlass you can go much heavier but I am content that I am safe and the boat is still seamanlike.
Flat fluked anchors are not commonplace in Scotland, I think it is because most places shallow enough to get your anchor down have a lot of kelp.
Our problem here anchoring in new and remote places are that many are very deep to close inshore, most of the shallow enough areas are already listed in the pilot books.
By the way, does anyone know where you can get the long U section bow fender that you can tie over the bow when recovering in rough water, I have seen one on a boat from the South Coast this year and it would away take some of the risk of denting my gel coat.

 

[VictorII]

I haven't been able to get hold of Sailing Today here in Belgium, so I would be very grateful if anyone could point me to a place where I can get this article.

And oh by the way, best advice I got regarding anchor size is: the biggest which will fit your bow roller. Which is exactly what I bought.

 

[VARNE]

I bought Manson Supreme Feb this year.
E-mailed them for recommendation ---27' 10" LOA. 2812kg [6200lb] Displacement.

Reply: 15lb supreme "with a good length of chain",

I use 10 metres of 8mm chain + anchorplait, and have found it sets first time, every time [no motoring it in or messing about] and never moves.

Worst conditions: F6 in a biggish swell two or three times.

Handling such a comparative lightweight is very easy handling, wonderful, but if I was off round the world perhaps I would go up a size [possibly unnnecesarilly].

Why not ask manufacturer ?

 

[Sadlermike]

I replaced a 35lb CQR, which dragged on average a little more than once per year, with a Rocna 10 (two thirds the weight). My choice was determined by the Rocna sizing chart and the fact that this was the largest Rocna I could fit in my anchor well. I was very concerned about downsizing. However, it has never dragged and I anchor more than 250 nights per year. Admittedly I have never anchored in stronger winds than force 9.

The surface area of the Rocna blade is similar to that of the larger CQR.

 

[jimbaerselman]

You are a brave man starting this theme again.
I notice that in a similar question in the 'improved' YM an 'expert' advises changing to 10 or 12 mm chain for a boat of your size, he however did not risk adressing the type of anchor, most boats of this size come with 8mm. chain which in my experience is pefectly adequate and much easier to handle. .

For a 27ft yacht? Hmmm. I've obviously got something very wrong. I lived with 8mm on a 40ft, 10 ton displacement yacht for 8 years. Or perhaps you were talking with someone else?

 

[Quandary]

Yachting Monthly chain sizing

No, this is the advice given to a enquirer in the Oct. issue of YM. Of course it is rubbish as is lot of the other info. (Kilchattan Bay - at the head of the Kyles of Bute?) This magazine badly needs proper editing by someone with an interest in the subject, unfortunately my sub. runs until the end of the year.

 

[bluedragon]

I bought Manson Supreme Feb this year.
E-mailed them for recommendation ---27' 10" LOA. 2812kg [6200lb] Displacement.

Reply: 15lb supreme "with a good length of chain",

I use 10 metres of 8mm chain + anchorplait, and have found it sets first time, every time [no motoring it in or messing about] and never moves.

Worst conditions: F6 in a biggish swell two or three times.

Handling such a comparative lightweight is very easy handling, wonderful, but if I was off round the world perhaps I would go up a size [possibly unnnecesarilly].

Why not ask manufacturer ?

We were happy with a 15 lbs Supreme on 40m of 8mm chain on 3T/27 footer. Too large and you may not be able to stow it properly even on the stemhead, and that can be a real liability and potentially dangerous. If this feels a bit too light for really heavy conditions, then carry a big storm anchor as well.

 

[BrianH]

A touch of fred drift but thought yet another anchor thread inappropriate.

I have just been passed a copy of 'Yacht Magazin', which I believe is current - difficult to tell as the only identification is "17/2009". This is the German language sailing magazine sold in Germany, Austria and Switzerland. It claims to be "Europas groesstes Segelmagazin" - by sales/circulation I presume.

It contains a test article on 10 anchors - all anchors are 15/16kg size. The ratings are summed up by 1 to 5 stars - 1 being unsatisfactory and 5 being very good. There are two test winners, both with 4 stars (good); the Manson Supreme, at 387 euros and the Kobra 2, at 198 euros.

The Rocna, which interests me as I own one, got only 2 stars (a grudging sort of satisfactory). It was, at 440 euros, the most expensive anchor of the ten. A damning comment, which from experience I cannot agree with is: "the setting is only in sand without problem, otherwise by luck."

As with all anchor tests, simulating real conditions is difficult and I suspect that this one is missing something somewhere. But then, I would say that, wouldn't I?

 

[Pete7]

I haven't been able to get hold of Sailing Today here in Belgium, so I would be very grateful if anyone could point me to a place where I can get this article.

And oh by the way, best advice I got regarding anchor size is: the biggest which will fit your bow roller. Which is exactly what I bought.

Having just read through the ST article, I thought it read like an advert for the Sarca Excel anchor which the Australian author subsequently fitted to his cat. His choice was influenced by what he could fit without modifications to the boat. Interestingly the test machine featured in the article used to test a variety of anchors seems to belong to the firm that make........ the Sarca Excel

http://www.anchorright.com.au/products/sarca-excel-anchor

Personally I think his choice which came out top looks like the Delta. So we won't be making any changes from our Delta which we bought because it seems to do well in many of the tests published and was sensibly priced.

Pete

 

[craigsmith]

I have just been passed a copy of 'Yacht Magazin', which I believe is current - difficult to tell as the only identification is "17/2009". This is the German language sailing magazine sold in Germany, Austria and Switzerland. It claims to be "Europas groesstes Segelmagazin" - by sales/circulation I presume.

The Yacht magazine test is a bit of a joke from what we can tell, although the detailed test methodology is never fully disclosed. We suspect the bottom type varied greatly and no repeat trials were conducted. They were just using a small yacht with no power or stability, very hard to get consistent results like that. In any case, a 15 kg brick should have had a good chance of attaining the low 250 daN force limit that they were "testing" to, so the whole thing is completely bizarre.

Having just read through the ST article, I thought it read like an advert for the Sarca Excel anchor which the Australian author subsequently fitted to his cat. His choice was influenced by what he could fit without modifications to the boat. Interestingly the test machine featured in the article used to test a variety of anchors seems to belong to the firm that make........ the Sarca Excel

I haven't seen the Sailing Today article but no doubt you will be talking about Jonathan Neeves, and a rewrite of something that was published in Australia last year. It was an absolutely shocking article, with blatantly wrong 'facts', selective referencing, invalid comparisons, and heavy commercial/nationalistic bias. Neeves himself has done no testing whatsoever, other than personal usage and as informed by Sarca.

The Sarca Excel is a Delta variant as you say. Neeves' choice was influenced by which manufacturer would give him an anchor... after we wouldn't give him one for free, apparently he tried Sarca.

If magazines are willing to publish this sort of thing, I'm afraid it can only be said to reflect accordingly on the editorial "journalistic" quality of the publication in general.

~

Peter wrote some interesting commentary on the problem of magazines the other day:

A boat’s anchor and the crews opinion of it is a very emotive subject. Usually a love or hate relationship. As most of us grow older we become less open to change and become entrenched in our opinions as to what is good or bad, what works and doesn’t. Very much so with anchors. “It’s worked for 50 yrs, why should I change now?” Some of these diehards don't even bother to read magazines espousing the latest technology toys, let alone the anchor test his subscription churns out every two years or so.

Reviewing the rubbish that is published in the disguise of so called “controlled tests” it is no wonder. The diehard is safer with his head in the sand and his old anchor. His information is coming from his own testing in the real world and he is only going to be persuaded by his mate who is even older, but who loves the new Rocna he was given as a centurion birthday present by the great grandson.

However in this modern information age the experience that is accumulated over many years is available at the push of a computer button. The younger generations and grey power combined jump the “experience time gap” by researching the internet for the facts and information they want. They may have seen a magazine ad, seen a interesting product in a boat show or down at the marina, or spoken to a mate about it, picked up a thread on an internet forum or typed “anchors” in his search box. He will also research the published results of various “tests” carried out by various authorities, both spurious and authentic and of course the thousands of words spewed out every year by the magazines under the guise of educating or informing their readers and in the process providing a vehicle for their advertising clients.

And here is the nub that the younger generations must grapple with. Sorting the facts from the fiction, the genuine from the bull****. And there is plenty of it. In amongst the hundreds of tests published over the last two decades, only a handful could be considered informative with somewhat accurate results. Firstly it's too time consuming and expensive and boring to actually do all of this, which is why most (all?) magazine anchor testing is as poor as it is. They don’t spend days out there with a team of men and equipment and a powerful boat. Only whatever can be dressed up as a "test".

Some manufacturers e.g. “Sarca” are even jumping on the bandwagon by advertising a “special” dedicated anchor testing tool so that all are equal, with Sarca more equal than others. In the interests of client education of course.

I am not aware of any one test by itself that tells the whole story, and some of these tests by such as by US Coast Guard or classification societies are now some 20 years out of date and what was considered a good base line is now irrelevant.

For the average sailor the practical tests carried out by West Marine for a consortium of boating magazines over the past few years, although not perfect, would have to be the best information available in recent years. They appear to run these tests every two or three years and are commercially motivated beyond the value of a six page article in a magazine.

I also liked the tests run by John Knox of Edinburgh for Practical Boat Owner. He tests in a very precise scientific manner using pulley stands for scope and a power winch through strain gauges for precise controlled pull in tidal pools near his home so he can duplicate exactly each test pull and view and monitor each anchor. He applies a engineering mind to his analysis and normalizes his findings to a common weight so all anchors are equal. He discusses the ratios of weight to blade area with his results, and tests for roll stability beyond yield and when under 90 and 180 degree veer stress. Unfortunately last we heard Knox was developing his own anchor design so now probably cannot be considered independent.

In any case, it's only when these sorts of approaches are utilized that we start to get some meaningful results. Anything less does more harm than good.

 

[NormanS]

Quote;

"Unfortunately last we heard Knox was developing his own anchor design so now probably cannot be considered independent."

A bit like yourself, then.