Anchors - Bigger is Better ?

[Kenomac]

Originally Posted by JonJo

But buying two correctly sized, not smaller, anchors is not cheaper than one bigger one and gives a fall back if you lose one, gives an option to use a different design if the other design is not perfect, allows deployment of 2 anchors in a 'V' to stop veering when the wind is forecast strong and steady in one direction. If your second or third anchors is alloy (Fortress seems the obvious choice) it is possible to deploy exactly where you want it from a dinghy. If the anchor chart suggests 20kg and you go for monster, say 35kg and you carry 2 anchors - I challenge anyone to deploy with complete safety from a dinghy (in fact if its not on a bow roller its basically going to be difficult to deploy - and how many yachts under 45' come with 2 bow rollers?)

I wonder how many of the bigger is better faction carry 2 anchors (both of which are 'new gen' and I wonder how many of the second anchors meet that same BIB criteria - and if not why not, people do report losing anchors - even if only temporarily. And where do they keep that second anchor?

Jonathan

If I need to set two anchors during a significant blow, they will be set in tandem on the same rode, not using two separate rodes. Less chance of tangling and much greater holding ability when both dig in, in a straight line. Think tug o' war with the big fat guy anchoring the end of the rode/rope. I've done this before, it works great.

[Delfin]

Originally Posted by Kenomac

If I need to set two anchors during a significant blow, they will be set in tandem on the same rode, not using two separate rodes. Less chance of tangling and much greater holding ability when both dig in, in a straight line. Think tug o' war with the big fat guy anchoring the end of the rode/rope. I've done this before, it works great.

That used to be my plan as well. I'm not so sure now. My reasons are that the trailing anchor attachment can't help but affect the normal burying characteristics of the primary anchor, and that as the primary drags, it creates disturbed soils that the secondary can't really dig into. My thinking now is that a properly designed snub line probably gives the most effective increase in the ability of the primary to hold you in one place.

[Stumble]

This whole issue is one that has gotten some conversation on another forum, and I still stick by the fundamental premise I came to there which is that. "Pound for pound, additional weight in the anchor increases holding power faster than weight in the chain." Assuming this premise is true, and there is a lot of justification to believe that it is, then best practice would be to move as much weight from the chain to the anchor as possible.

In reality most cruisers carry anchoring systems that were designed decades ago when electric windlasses were expensive and very rare. With modern handling equipment the small anchor + lots of chain model, is incredibly inefficient requires carrying a huge amount of excess weight and provides minimal holding power. All in all this system is really due for a rethink.

Modern anchors generally create 40lbs of holding power or more for every pound of dead weight they have. While chain generates about 1lbs of holding power for every pound of weight. This massive difference is because modern anchors are incredibly efficient at converting their weight into holding power, while chain really adds nothing but dead weight.

So when we consider the 'average' anchoring system on a 40' cruiser what do we find? Typically a 60lbs primary anchor and 300' of 3/8BBB chain weighing in at 1.7lbs/foot. Then a secondary anchor of a slightly smaller size and the same amount of chain used to increase holding power in storms. A perfectly reasonable and reliable system... Until you consider that when it's all added up this system comes out to 1,070lbs of chain and 120lbs of anchor. Even while we know that anchor weight is much more important that chain weight.

Instead of this, my recommendation is to
1) get rid of the second anchor entirely, saving over 500lbs in weight alone
2) switch from 3/8BBB to 1/4 Grade 70 chain which will save 290lbs
3) Get rid of the 60lbs anchor and get a 120lbs one

All in all this saves 725lbs of weight from the bow of the boat, puts the weight where it matters the most, and puts an anchor on the boat that will hold thru anything. Heck it's heavy enough that it could work as a deadweight anchor in calm conditions. The only trick to this is that it pretty much requires an electric windlass, without one you would need to stick with a traditional system. But amazingly enough not a huge windlass, the Lewmar 1000 would easily handle this system.

Evan assuming you wanted to keep a completely separate anchor for some reason, switching to 1/4 G70 chain alone would save enough weight that you could switch to twin 120lbs anchors and still save weight.

[Shas Cho]

Originally Posted by JonJo

It seems as if they got rid of their old gen anchors, CQRs, Deltas, Bruces and immediately bought anchors much bigger, often 2 sizes bigger. No-one seems to have gone the intermediate step.

Safety is best approached from the right side.
I can't imagine anyone buying a questionable anchor
with the intention of purchasing increasingly large models
until their boat stopped dragging.

It seems to me, sir,
that if you would prefer to stick with the anchor you have
and spend your well-squeezed money
on larger chain and shackles,
you should do that,
whether you gain a consensus here or not.

[Pete7]

Originally Posted by Stumble

In reality most cruisers carry anchoring systems that were designed decades ago when electric windlasses were expensive and very rare. With modern handling equipment the small anchor + lots of chain model, is incredibly inefficient requires carrying a huge amount of excess weight and provides minimal holding power. All in all this system is really due for a rethink.

So when we consider the 'average' anchoring system on a 40' cruiser what do we find? Typically a 60lbs primary anchor and 300' of 3/8BBB chain weighing in at 1.7lbs/foot. Then a secondary anchor of a slightly smaller size and the same amount of chain used to increase holding power in storms. A perfectly reasonable and reliable system... Until you consider that when it's all added up this system comes out to 1,070lbs of chain and 120lbs of anchor. Even while we know that anchor weight is much more important that chain weight.

Instead of this, my recommendation is to
1) get rid of the second anchor entirely, saving over 500lbs in weight alone
2) switch from 3/8BBB to 1/4 Grade 70 chain which will save 290lbs
3) Get rid of the 60lbs anchor and get a 120lbs one

All in all this saves 725lbs of weight from the bow of the boat, puts the weight where it matters the most, and puts an anchor on the boat that will hold thru anything. Heck it's heavy enough that it could work as a deadweight anchor in calm conditions. The only trick to this is that it pretty much requires an electric windlass, without one you would need to stick with a traditional system. But amazingly enough not a huge windlass, the Lewmar 1000 would easily handle this system.

Greg, I disagree (which is a rare occurence on an anchoring thread )

Firstly; I think you have over estimated the amount of chain carried on a cruising yacht. 300ft is a huge amount and as you say weighs a lot. We carry 30m (100ft) though in retrospect I should have bought 45m for anchoring in areas with 8m tides. Perhaps we should have a poll to see what everyone carries for the main rode.

Secondly; we only anchor in protected areas so even with the tide running everytime I look at the chain most of it is just laying on the seabed. The anchor is just there to stop the chain from moving. We can anchor in more exposed areas but it is just unpleasant for life on board if you are constantly bouncing around.

Thirdly; I think you and Jonjo are talking to the converted on here, its just the cost of new generation anchors being the stubbling block for many. Walk around any UK marina and the majority of anchors are CQR, with bruce and Deltas coming a close second. The number of new generation anchors (Spade, Rocna, Extreme, et al) is tiny in comparision. Why? because anchors don't wear out, so folk keep what the boat came with. Ours came with a CQR copy and despite the previous owner explaining he had trouble setting it, he never changed it in 19 years. I did in the first week of ownership and we now have a 10kg Delta as the main anchor, though this may change in due course, but only to a similar sized Fortress/Rocna/Manson/Kobra 2. At 31ft I want to have a working anchor for most occasions which I can lift by hand or if the tide is running using the manual winch. For the lee shore in a storm senario I want a second larger anchor. This means the working anchor is easy to handle by hand so no need for electric winches and more expense.

Also since anchors don't wear out like sails and ropes folk find it hard to justify new chain and expensive anchors, times are hard and there are other priorities on board for folk with squeezed budgets.

Fourthly; I don't agree with getting rid of the second anchor. Even with diving equipment on board there have been several times I have let the lot go because it just wasn't retrievable. Thankfully it has tended to be cheap grapple anchors which are easily replaced. What is certainly popular in the UK is a Fortress as the second anchor, ours is one size up (FX16) and since they like lots of scope we have 20m (60ft) of chain plus 50m (160ft) of rope. This is light and easily stowed. The price paid in the UK for second hand Fortresses is astonishing, often 3/4 of the new price if you can find one.

So in summary we have a working sized anchor which is easy to handle and therefore likely to be used, which is also within our budget and meets the need for most occasions and if its blowing a hoolie we are going somewhere else.

Pete

[congo]

Pete 7

Much of what you say is true Re the invasion of new generation anchors, most marinas, 95% are CQR Delta and Bruce or copies, I disagree, anchors do ware out, pivoting moving parts eventually make a good CQR, Dan forth style sand anchors pretty much useless, simply because the original physics open up with ware.

Delta anchors do not have this problem, they were a step in the right direction when released, you certainly will not ware them out.

The amazing thing with all these anchor threads Re New generation anchors, if you look back through the earlier threads you find a progression of these New generation anchors dragging ware the old CQR didn't, what’s more amazing is conformation in tune with new generation anchors dragging is the Bigger is Better slogan ever increasing?

We do not recommend a larger size anchor unless the boat the anchor is going on is right at the top end of the anchors certified scale, then we will recommend the next size up, this works well for us.

Further in Australia we must have a lot more adventurous yachters as they find themselves caught out, exposed regularly in weather conditions not predicted.

The danger with a much larger anchor is that if you cannot bury the fluke by powering down whether the motor is not powerful enough or if it is sand over hard mud and the like the rear of the fluke can stick out and be lassoed, tangled with anchor chain in violent wind shifts, that is the reality in Australia, violent wind shifts are very common and many times it is blue Skye and not predicted, you can be facing north, the wind drops and then with vengeance slams you back to the south.

Regards Rex.

[congo]

There is no disputing a larger surface era will produce more holding power providing the anchors design will allow the larger fluke to bury, keep digging down without restrictions.

A well designed anchor smaller in fluke size that will bury deep in most cases is a more practical anchor design than some, now to really through in a new dement ion steel anchors verses alloy anchors, I must say we have been blown away with our independent sea trials on our alloy Excel, to date we cannot tell the difference.

Yes and I am talking all sea floor types in comparison to steel, dare I say it, maybe I should start a new thread, it's true Excel alloy digs in first time every time. In all seriousness I have been blown away with its light weight performance and it has changed a very long negative view of mine on alloy anchors performance.

Regards Rex.

[lancelot9898]

Rex,

You raise an interesting point about the anchor chain becoming tangled with the anchor with violent wind shifts. I switched from my 35 lb Cqr to a 45 lb Manson Supreme some 6 years ago and wonder if that roll bar presents a problem as you mentioned? I agree with you about too much weight is being given to anchor weight and I'ld rather have the excess weight in the chain. Case in point is that little 35 cqr all by its lonesome held me(on a 24000 lbs displacement boat) in a Cat 1 hurricane some years ago. Never will I be aboard again during a hurricane, but to me the holding power is dependent on the bottom conditions and how well the anchor sets.

[congo]

lancelot9898

Yes well we have been doing boat shows for twenty years and I have heard many stories such as yours with small anchors, a prime example is Noelexs thread, his octopus thread, Noelex stated it was blowing approx 25 knots with his Rocna, look at the octopus, a perfect situation in a wind shift for the chain to pick out the anchor or tangle. In twenty five knots with a smaller anchor would be well buried. Down side is there would be no room for the octopus.

It’s not just the bigger is better slogan, the one that gets me is the now many saying not one, but two sizes larger, if the new gen anchors are so good why oh why aren’t we going the other way, the next irritation I have with two sizes bigger, especially in concave design if your trying to lesson the load on the winch forget it, many here in Australia are stepping up to larger winches to cope, the real mind blower now is I know of one winch company that will warranty there winch but only if it is not a concave anchor design.

Regards Rex.

[noelex 77]

This is a photo of the anchor from the "octopus" incident. The octopus dug out sand from around the fluke to make his home which was why I said.

Originally Posted by noelex 77

Under engine power alone my Rocna normally at least completely buries the fluke which makes my anchor immune. My current anchorage has very hard sand so the anchor has set with the fluke only just covered and some enterprising octopus decided a few of days ago that he could dig out the sand under the fluke and make a nice home.

Each day a bit more sand is dug out from under the anchor and there is steady accumulation of pippi shells that have been eaten and discarded and small stones that are obviously important for the best octopus homes.

There is no problems setting a larger anchor.



The thread is here:
http://www.cruisersforum.com/forums/...na-110176.html

[noelex 77]

Originally Posted by congo

Australia are stepping up to larger winches to cope, the real mind blower now is I know of one winch company that will warranty there winch but only if it is not a concave anchor design.

It does not surprise me the concave anchors set so well that if you run out of patience and try to rapidly break the anchor out with the winch you are putting a very large load on it.
The traditional convex anchors do not set as well and can often be easily hauled up even after a blow.

[JonJo]

An interesting facet of concave anchors is that owners make lifting all that seabed into an asset (and defend the characteristic to the death). The fact that the fluke is clogged would suggest to me the anchor has stopped working and the device at the end of the chain is simply 'dead weight'. Of course the owners see it as proof the anchor has set (though how an anchor with a clogged fluke can take an increase of 10 knots of wind is never explained).

No wonder deck washes are essential.

It has been suggested that the Mantus wide roll bar was devised to ensure this clogging did not happen,

Testing with the Mantus does show that clogging is not the issue it is with those concave anchors with smaller (narrower) roll bars and uplifted heels causing compression and hence blockage. Mantus in taking that route must have sacrificed some potential sales as the large hoop will not fit on many vessels (and is not the most attractive feature) - so they must have been strongly motivated away from 'fluke clogging' at the expense of beauty and fitting ability.

So we have one concave roll bar anchor where clogging is an asset and another concave roll bar anchor specifically designed that clogging cannot occur.

Takes all sorts, I suppose.

Jonathan

[sailorboy1]

I don't know if I can take it much longer:

So what is the perfect anchor and size? Surely after all this there is a real answer that doesn't use the word depends.

[congo]

Noelex,

I am surprised, if I sold you a winch and you used it to break your anchor out then I wouldn’t be giving you a warranty either. I don’t know of any one that breaks their anchor out with their winch.

Yes many motor forward and back trying to shake-loosen some of this mud but in firm mud it simply will not drop of as many know; I have seen some trying to winch up a barrow load of mud and then prodding at it before locating on the bow, this is where the winches are giving up the Ghost. P Smith himself justifies this by saying well at least you know your anchor has been set.

This is a bit like looking out of the window when driving a car to see if the wheels turn, (connected to the steering wheel) If you power down and your boat stops like it was on a mooring then obviously your anchor has buried into whatever you have deployed it in.

Your above photo as an example for an anchor that was power set, and then holding you in twenty five knots, your words, well, it is poorly set, even the shank is still sitting up proud, lovely cavity for the chain to slide under, either go smaller in size or try a proven convex designed anchor that continues to burry.

Regards Rex.

[Cotemar]

Jonjo,
Good point. The roll bars on these new gen concave anchors have vast differences in size.
The larger they are the better, but then you run the risk of them hitting a railing or netting as they come over the anchor roller as they seat.