Anchor size?

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<span style="color:blue"> I know all the books talk about setting two anchors in various configurations, but how much do people do it in real life? Pretty much all of the boats we see seem to lie to a single anchor. </span>

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It would be a good question for a pool..

my own answer:
I've been living-aboard during 13 years.. at the begining, I was using a single CQR. After several anchoring problems, I started to use both a plough and a flat anchor, tandem set.. but this was quite difficult to set and to retrieve.. and I have had anchoring problems too.. until I changed for one of those "new generation" anchor.

Since then, (including in the river mouths of Brasil, where current is changing with tide) i have used two anchors less than half a dozaine of times..

But this is only my own experience.. /forums/images/graemlins/blush.gif
 
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'Now and then?' What is the most popular anchor at the current time for most cruising yachts? I wouldnt mind betting that the CQR is in the top 3 at least, if not the leader.

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The most popular buger in the world is McDonalds but certianly does not make it the best.

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I'm not sure that's relevant. Boats last a long time, and most people don't replace anchors. Just because the anchor you have is good enough doesn't mean that there isn't something better. For what it's worth, the fact that there is something better available doesn't mean you have to replace what you have.

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100% correct

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Look at new boats: most that I am familiar with come with Delta anchors. Give it a few years and Delta anchors will be the dominant anchor out there for that simple reason.

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Bet you it won't /forums/images/graemlins/smile.gif Most of the boats coming out new kitted with Deltas is due to the 'package' pricing of Lewmar gear to the OEM's i.e very sharp prices when you buy the boat lot of Lewmar gear like anchor, winches (anchor and sheet), electronics and so on. Even better if you buy that lots 30-40-50 plus times a year. Not to mention the massive $$ spent on advertising Deltas (see McDonalds comment above). There is also a very large 'Monkey see, Monkey do' factor with many anchors and other gear. (flame suit is on /forums/images/graemlins/smile.gif )

Personally I'd have a Shark over a Delta, works better, holds more, EU made not Chinese and costs a lot less.

Yeap there is many raving about the Sarca. Sounds abit like "why does this piece of s**t anchor wannabe hold bu**er all" /forums/images/graemlins/smile.gif /forums/images/graemlins/smile.gif. It's heard frequently here. FYI the Sarca is the second most common anchor we replace due to poor performance. The Sarca is not one any cruiser with more than one brain cell should consider as a viable option. Harsh I know but sadly quite true.
 
Re Hylas' thoughts regarding anchors in tandem :
When I first put down our mooring it consisted of a 40 lb conventional Danforth twin fluke anchor to the east (ie windward) and a 45 lb Danforth plough anchor to the west in a bridle arrangement.
The Danforth plough had been a bower anchor on a previous boat, a task it was singularly useless at - it loved sliding along the bottom without digging in. But it has been down there for 4 years now, and is (finally!) reasonably well buried..... it does not have to cope with much, as we very rarely get winds out of the west.

Anyway, I noticed when snorkelling on the mooring one day (I routinely dive on it every 3 months as well) that the Danforth to the east had 'tripped out', presumably in a rather strong squall (F 8 easily) we had the day before, and had not re-buried itself yet.
So I came back next day with my scuba tank and a 13 lb Danforth bought in the local chandlery (that was all I could find at short notice), and hooked it up in series (not parallel) with the 40 lb Danforth. They are both completely buried now, and boy do they hold well together in tandem!
Phoenix has since been through F8+ gusts on this tandem arrangement with no worries.

And yes, I do have plenty of scope in this mooring, which is considerably helped by having 15' of heavy stud link ships anchor chain in the system just where it rises off the bottom (where is where all moorings seem to get hammered the most IMHO).

PS to GMac - I never said that the CQR was 'best' just that it is very popular still with many of the cruising yachts we see out here.
Although I must admit that Deltas, Bruces, Spades, and Brittanys are also becoming more popular.
And I am sure that these modern Rocnas and others will quickly dig in and claim their fair share of the market as well.
 
Re: Anchor in tandem

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<span style="color:blue"> Re Hylas' thoughts regarding anchors in tandem :
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Yes, as I was not happy at all with my plough anchor, I did try the tandem set technique.. with no more success..

I personally almost lost my boat trying out this idea. At the time, my first anchor dragged, so I decided to try something new. I added a smaller anchor in front of the large one. This worsened the holding power as opposed to doubling it, drifting swiftly on the smaller anchor while the larger one couldn’t grip at all.

I have done a series of approximately 70 tandem anchorages in the clear waters of the Med, diving on nearly all of them.. in 62% of the cases, only one anchor was set.. During bad weather, you will not have the possibility to dive to check your anchors.. and you only have to “trust” your anchors.. Which is what I call “the Russian Roulette” anchoring..

Therefore attaching two anchors to one rode, known as tandem anchoring, should be avoided.


On an imaginary level, it might seem like two anchors should hold better than one. This is however only true when both anchors can set perfectly. Whatever anchoring technique you use, there’s never a guarantee that both anchors are going to set well. On the contrary, once the first anchor is set in the seafloor, it will hinder the other anchor from setting also.

When an anchor has dragged, a trench formed behind it and this quickly backfilled with loose un-compacted sand. These areas can be still visible after several tides and may explain why some popular anchorages are criss-crossed with patches of poor holding.

Then, if the most proximal anchor set, they are very good chances (?) that the distal anchor will fall down in this loose bottom, with, as a consequence, a poor holding!.


Below, you will also find a letter from Jean Louis GOLDSCHMID (Nautical Center of Glénans) published in N° 114 of Glénans news letter (August 83) (“badly” translated from French)

<< The Tandem set technique it is a very good technique with Fisherman anchors and I personally made some experiment at time when the Glénans’s boats only had this type of anchors on board.

On the other hand,. I began one day to have doubts while seeing tandem set anchored boats dragging.
I thus carried out a series of measurements of traction with a motor boat. Almost all the tests gave the same results: one needed 200 rpm less to drag 2 tandem set anchors (CQR or Fluke anchors) than only one of these anchors alone. I thus checked what occurred, with small anchor on the dry maërl beach of “PEN MARYSE” in the Archipelago of Glénans, pulling by hand.

First problem with the CQR:, it doesn’t have any fixation hole to attach the second anchor (that should have been a sufficient reason for not using this technique), I thus tested the bar, the trip line hole, the elbow of the shank. On these 3 points. the effect is the same one: the articulation plays badly, the plow cannot dig in. Remain the extremity of the shank, but it is not better. Almost each time, the chain comes to obstruct the plow The whole system does hold only on the most distant anchor. If this one is smaller, it holds less than only the large anchor one. I noted too that an anchor holds very badly in the furrow of another.

With the “Fluke” anchors: this is again the same problem of devoted fixation, and it does not have there anything which can be used except sometimes the trip line rings which are usually not strong enough. However, from time to time y obtained results comparable with the holding of only one anchor.

I thus concluded from it, that I had sufficiently poisoned my life by re-installed useless scrap heap to definitively give up the tandem set technique.
 
Re: Anchor in tandem

OK Chief, you dont have to tell me that my tandem anchor arrangement on my mooring should not work - I am merely reporting my own observations that (in this instance) it seems to work very well.
But I acknowledge that this is for a mooring, where both anchors are down all the time, and have a good opportunity to get properly buried.

A correction : Re my previous post, I had said the anchors were in series, but on reflection now I guess they are effectively in parallel (re how the cables are attached), although they are both in the same line when load is applied. The smaller anchor is behind the bigger one, on about 6' of chain, the end of which is attached to the mooring chain about 1' ahead of the main anchor.
 
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I know all the books talk about setting two anchors in various configurations, but how much do people do it in real life? Pretty much all of the boats we see seem to lie to a single anchor

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1. If it's a strong wind from a predictable direction, you'll drop two anchors to minimise the snatches when you yaw from side to side:

a. Drop your bower with at least 6xdepth, dig it in with a good burst of astern

b. Prepare the kedge, motor round your bower in a semicircle (with the helm set away from the bower) until you're facing into wind with the bower on your beam. Drop the kedge, allow the boat to drop back onto the bower.

c. Secure the kedge when you're doing a yaw towards it, let the yaw back start the dig in, then motor back against the kedge to complete the dig in.

d. Sleep sound with much reduced yawing and two anchors working for you.

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2. If you want to drop two anchors to reliably survive a tide reversal

a. Drop your bower and dig it in as above. Then allow as much chain out as you can to position yourself well down tide.

b. Drop the kedge - from the stern, or even from a dinghy, if you don't have enough bower chain).

c. Pull in the bower til you have 6xHW depth out there (maybe a bit less, but be careful not to trip it out) while paying off the kedge.

d. Dig in the kedge by trying to pull it home (it has to be more than 6xcurrent depth away for this to work).

e. Lash both rodes together while they're pulling against each other, then pay out enough from both to drop the lashing below your keel. Make up the kedge rope to take the strain (it's a better spring than the chain) and make the chain up with some slack. Anti-chafe the rope.

f. go ashore for that meal while the tide changes without worrying about an anchor trip.

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3. Tandem anchors - for when you have little swingin room and rather a lot of depth. This is a variation on the 'chum' theme:

a. Without dropping your bower, let out about 3m of chain. Shackle the kedge onto the chain.

b. Drop the bower, then the kedge, letting out not enough chain to catch the bottom. Manouvre to your anchor position.

c. Set up some astern movement, let the chain out. Pay chain out/move astern so that it is pulling at not more than about 20 degrees off the vertical.

d. When you've got the appropriate length of chain out, gently pull astern to dig in, praying that the 'chum' or 'kellet' or whatever you want to call that weight. doesn't allow the chain to lift too far off the bottom.

e. Sleep uneasy if the wind gets up.
 
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And yes, I do have plenty of scope in this mooring, which is considerably helped by having 15' of heavy stud link ships anchor chain in the system just where it rises off the bottom (where is where all moorings seem to get hammered the most IMHO).

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Our moorings down here have real heavy stud link (32-40mm) then to a 20-24mm chain to a 16mm chain to a smaller chain or rope to the boat. Using progressivly heavier chain is so when the weather turns bad the boat has to lift increasingly heavier chain and give the whole thing some elasticity or shock absorbsion. It would have to be real real extreme before the mooring weights have to take any load.

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PS to GMac - I never said that the CQR was 'best' just that it is very popular still with many of the cruising yachts we see out here.
Although I must admit that Deltas, Bruces, Spades, and Brittanys are also becoming more popular.
And I am sure that these modern Rocnas and others will quickly dig in and claim their fair share of the market as well.

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True. Many do regard the most popular as best though hence my "Monkey see Monkey do" comment. A classic example down here is the Sarca. See many on small boats so many think they are good when in fact they are 1st class c*ap backed by some very very good marketing. We refer to them as the 'WMD or McDonalds anchor' /forums/images/graemlins/shocked.gif
 
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