Which anchor set have you tried,,, tandem or V formation

Neeves said:
No, never seen anyone use a tandem anchor set up, let alone seen it set - just a guess (its the idea of setting it up that puts us off - the one ploughing behind the other just makes it even less attractive). An Anchor Right Excel has a 'tandem' attachment point or a hole on which to attach a trip line at the base of the shank, Spade has a hole at the back of the fluke (they are quite common). Who said they needed to be the same design, an idea of having more than one decent sized anchor (all of which can be the primary) is that they can all be different styles - making the most of compromise and not putting all you eggs in one basket:)

Jonathan
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Rocna "claim" anyway to have spent some time calculating to get the tandem attachment point in the right place to keep the setting angle correct, rather than just an attachment point for a trip line.

Anyone have any actual experience?
 
GHA said:
Rocna "claim" anyway to have spent some time calculating to get the tandem attachment point in the right place to keep the setting angle correct, rather than just an attachment point for a trip line.

Anyone have any actual experience?
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Rocna have 2 holes, one at the base of the shank and one at the centre and rear of the fluke. Spade have one at the centre and rear of the fluke and the Excel has one at the base of the shank.

No never tried, but now you mention it, if I had a Rocna I would not know which to use:(

Jonathan
 
In a very well written article about heavy -duty anchoring Robert Lowe ( Yachting monthly January 1989 ) explains why one should not back the anchor in a tandem or triple configuration.
So DON´T back one on to another but use a separate branch of chain.
Pic´s in the article show why. In short : with backed anchors at a wind shift, the one closest to the yacht will be pulled out of the bottom with NO chance to reset.
I have used this technique some times when I had to leave the boat unattended for some time.

The “V “ formation is used a lot by me, simply because it is the only one that a single hander with a hand operated anchor winch can use when the wind unexpectedly picks up.
 
I have never used a tandem arrangement. After all you'd have to recover the first anchor to do it. I often deploy a second Fortress at an angle to the Rocna in a wide V towards any expected increased wind shift. Makes sense to me. With the usual single anchor on a multi we always use the bridle, it kills swinging and veering about instantly!
 
we set our first anchor in the conventional way then deploy the second large aluminium anchor on all rope rode as an angle to share/take most of the load. We use the rib to tow the boat forward a little with the second anchor rode then drop the anchor quickly so the second anchor is sharing load. I would rather load up the second anchor as it gives snubbing effect on the all rope set up. Only when the load increases does it load the chain. I know this seems the wrong way around but it does make for less shear and more comfort. As the boat shears, the chain on the main anchor is not loaded so drags across the seabed creating a damper effect. it seems to work well. in the bigger gusts, both tend to be fully loaded due to the stretch in the rope.
we did a lot of experimenting with anchors on an Atlantic circuit (didnt like paying for marina berths). Tandem didnt work for us as under load the main anchor would lift if it wasnt fully set. I watch this happen whilst snorkeling over the anchors.
 
We have used two anchors on a couple of occasions it works. Each laid along the same line with the boat in the middle, if that makes sense so the anchors are both pulling to the middle - where the bow is, but only one will ever be loaded.

<-------------------boat-------------------->

the reason is to limit the swing of the boat if the wind changes, a pig to set up and dismantle though.
 
Marsupial said:
We have used two anchors on a couple of occasions it works. Each laid along the same line with the boat in the middle, if that makes sense so the anchors are both pulling to the middle - where the bow is, but only one will ever be loaded.

<-------------------boat-------------------->

the reason is to limit the swing of the boat if the wind changes, a pig to set up and dismantle though.
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Provided that you mean that both rodes are brought to a point under the bows, you have just described a Bahamian Moor. See#14.

PS. Don't make the two rodes too tight, or you will put an awful strain on them if the wind comes from across the line of the rodes.
 
NormanS said:
Provided that you mean that both rodes are brought to a point under the bows, you have just described a Bahamian Moor. See#14.

PS. Don't make the two rodes too tight, or you will put an awful strain on them if the wind comes from across the line of the rodes.
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Thanks for that - never to old to learn, I was unaware it was an actual technique.

Agree with the not too tight comment, the boat must be allowed to swing but not by much. So far I ve not been the position of a wind across the line but imagined I would let one go and buoy it off to retrieve later - assuming there would be enough room for the boat to lay to the new direction . . . . . Murphy's says there wont be.

One anchor on chain and the other on warp means there is less chance of shredding gelcoat but I put a heavy shackle on the warp to keep it below the keel and rudder - like I said its a pig to set up and dismantle.
 
We have used a tandem set up in very soft mud - not because there would be big blow but because of current. Once was at Kourou, French Guyana and once at Charleston, South Carolina. Our main anchor was a 25kg Delta and we attached a Fortress FX37 ahead of this on 4m of chain. Worked a treat including with reversing tide. It is possible that the Fortress alone would do the trick but we went for belt and braces. We did have about 20kts wind through Kourou and other boats did drag. N.B. don't use the hole at the front of the stock which is for a tripping line.
 
I have used tandem setup in coral rubble as I needed to get as much weight as possible on the floor as their was nothing firm for the anchor to bite into. The plough with 5m chain to danforth did hold when neither would alone.
 
From some of the replies of those who have actually used a tandem set up (and there are few users who seem to have tried it) there is a vague suggestion that the anchor nearest the yacht might be lifted, in very strong wind, in which case it seems to act more like a kellet than an anchor (but keeping the load on the further away anchor as near horizontal as possible).

I know little about this, so feel well qualified to comment:)

I assume by tandem one means deploying 2 anchors in line, one anchor attached to the second.

On the assumption anchors hold better if set more deeply then the load on each of 2 anchors will be half the load, had there only been one anchor. Consequently 2 anchors will set less deeply than one anchor. Two 'half set' anchor seems to me to suggest the one nearest the yacht, in strong wind, has a great chance of breaking free as the chain tightens up, and becomes (what looks like a straight line - which is what you would have in 40 knots). If one assumes the anchors weight 20kg then the anchor nearest the yacht is acting now as a kellet, or about an extra 13m of 8mm chain (so not very much) - and if its not too well set I would no be surprised if it lifted.

For those 2 half set anchors to set more deeply you would need an increased load, which is what would have happened as the wind developed to 40 knots but superimposed on this is the idea that the nearest anchor is constantly having its shank lifted as the chain tightens and the load being imposed at varying angles as the yacht veers not the best scenario for a well set anchor - though modern anchors do set on short scopes (or scopes that are off the seabed).

Someone will argue that this will be invalid for a modern anchor, not sure about this (as I cannot see that it makes any difference) but I would rather have an independently well set anchor, set as deeply as possibly, and another independently well set anchor set as deeply as possible on 2 different rodes (in a 'V' - assuming a wind not likely to veer through more than 90 degrees) rather than trust to 2 anchors (no matter how efficient - but whose setting ability I cannot see).

I vaguely recall an American anchor design, 6-18 months ago?, that actually was a tandem device. One anchor nested into another - but that's about all I can recall. I assume it worked - or it would not have been on the market, but I'm not sure how they defined 'worked'

Jonathan
 
I have used a tandom anchoring arrangement. It not a great option, but it does occasionally have its uses.
If you have a reasonable amount of rode between the two anchors both anchors should perform in undisturbed substraite. Once an anchor has dragged the chance of it resetting is not great anyway.

The biggest problem is getting both anchors to set well. New generation anchors set within a metre or so. Any slack in the rode or difference in setting distance between the two anchors means you end up with one unset.

With any arrangement of two anchors its very difficult to share the load. There are some benefits to reduced yawning with two anchors in a V, but I think the extra holding capacity is only minor.

Some of the benefits of setting two anchors are psychological. When sitting at anchor with bad weather forcast you feel like there should be something that should be done. Setting two anchors fills that need.
If you do set up two anchors in a V make sure to consider that you will swing differently to neighbours that are only using one anchor. Also consider the implications if you do drag. The rodes can get very tangled.
One major benefit is that if you an unreliable anchor, setting two different models gives you a better chance that one will work.

For holding a single slightly larger anchor will have the same effect as two slightly smaller anchors. The single slightly larger option is easier, quicker, simpler and if you use this as everyday anchor you don't have to do anything at 3 am (which by some unwritten nautical rule is generally when the wind arrives)


Note the above refers only to holding. Setting two anchors to reduce your swinging area, or to align the boat with the swell are good reasons to set two anchors.
 
noelex said:
I have used a tandom anchoring arrangement. It not a great option, but it does occasionally have its uses.
If you have a reasonable amount of rode between the two anchors both anchors should perform in undisturbed substraite. Once an anchor has dragged the chance of it resetting is not great anyway.

The biggest problem is getting both anchors to set well. New generation anchors set within a metre or so. Any slack in the rode or difference in setting distance between the two anchors means you end up with one unset.

With any arrangement of two anchors its very difficult to share the load. There are some benefits to reduced yawning with two anchors in a V, but I think the extra holding capacity is only minor.

Some of the benefits of setting two anchors are psychological. When sitting at anchor with bad weather forcast you feel like there should be something that should be done. Setting two anchors fills that need.
If you do set up two anchors in a V make sure to consider that you will swing differently to neighbours that are only using one anchor. Also consider the implications if you do drag. The rodes can get very tangled.
One major benefit is that if you an unreliable anchor, setting two different models gives you a better chance that one will work.

For holding a single slightly larger anchor will have the same effect as two slightly smaller anchors. The single slightly larger option is easier, quicker, simpler and if you use this as everyday anchor you don't have to do anything at 3 am (which by some unwritten nautical rule is generally when the wind arrives)


Note the above refers only to holding. Setting two anchors to reduce your swinging area, or to align the boat with the swell are good reasons to set two anchors.
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As was mentioned earlier by a number of posters the setting of 2 anchors is not intended to double hold, it allows each anchor to be loaded in alignment to the shank (as the anchor was designed) and it reduces veering. The old phurphy that 2 anchors set in a 'V' doubles holding has not been mentioned. Reducing veering reduces the development of snatch loads and snatch loads by definition are loads higher than would be expected and desired as they are the result of the yacht 'sailing'. Snatch loads are uncomfortable, even if nothing else.

Any yacht that veers sufficiently that it is too close to its neighbour has anchored to close in the first place.

Reading a whole host of anchor threads one thing does stand out - the reports of modern anchors dragging are notable by their absence. Though it was common and still is for those using older style anchors anyone with a new anchor does not report (or admit - which might be a problem) their anchor drags. This observation covers most designs and seems to embrace those with big anchors and even small anchors. In fact there are lots of stories, and videos, of small anchors doing exceptional things - You Tube 'Granny Smith'

One thing that causes any anchor, including modern ones, to drag is catching something in the toe, or fluke. In popular anchorages: Beer cans, old towel (we caught a gas cylinder once) in more isolated places: waterlogged wood, large piece of seaweed and whale bones. Relying on one anchor, big or small, means if this happens, your anchor will drag and you have no back up. If its benign no problem but.

Relying on one big anchor is fine - but no anchor works everywhere. Some anchors will not self right and set easily in thin mud, some anchors clog in weed. To have a monster big one, just in case of the storm a year, means that if your big one does not work - its devil to change (unless you are lucky to have 2 big ones and 2 bow rollers) and its just as much a devil to get the second big one out (where do you store it?) and onto the rode. Having a normal sized modern anchor means you are geared up for most eventualities, your second and third anchor is easy to deploy and if you have different styles they will work where other styles might not.

And why will the second anchor in a tandem not set. If you set the outward anchor first, it is now set and will not allow you to set the one closer to you, if you deploy them both then the closer will set first (possibly leaving the other one laying on its side). Who knows what will happen when the wind gets up - not a scenario with which I would be totally comfortable.

I'm with a well known politician, when the chips are down - 'V' for Victory.

Jonathan
 
This is a bit like a 'how long is a piece of string' type post but having never set two anchors I am a total innocent so please be gentle ;)

The essence is, how far apart to lay each anchor and should the rodes be of similar length ?

Next season we will be in a position to set a V as we are getting a Fortress. Thinking through how I may deploy it, leads me to conclude it will have to be by using the mothership.

Of course, if we have advanced warning of a severe gale and are forced to stay where we are, the second anchor could be laid by dinghy. I think though that the most likely scenario is that we will already be anchored, caught out by winds that grow more than forecast and then pick up a new gale warning which would mean we would like the additional security of a second anchor. At this point, use of the dinghy will be a no-no so we will be forced to lay the second anchor by using the boat. Is it important that I motor forward far enough to make sure that each leg of the V is the same length as the other ? Secondly, how far apart (as a %age of the length of the original V) should it be laid ?

I ask this because if the answer is that the two legs of the V should be equal, are there any likely difficulties we might encounter when motoring to the new desired drop point ? It may be that people do this regularly and it is easy, in which case this post is pointless. It may also be that people have tried this and got into trouble with their existing rode. As I said, having never done it before, I would be interested in people's real life experiences.

I will definitely practice in calm conditions but we all know how things can go pear shaped when under stress and with a low level of confidence when the wind is screaming.

TIA Paul
 
Storyline said:
The essence is, how far apart to lay each anchor and should the rodes be of similar length ? .........
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This is a question that may be easily answered sitting at a desk at home but is very different in reality. Firstly your 'advance warning of a severe gale' is a highly unlikely scenario. Nobody (very few people?) lays a second anchor under routine gale conditions until it becomes obvious that it would be a good thing. This excludes really mammoth winds such as hurricanes and typhoons, of course. When the boat begins serious yawing, other boats and maybe yours are dragging, the chain is coming up straight and tight at the extremities of some yaws, it is fairly apparent that something must be done.

The first action of most skippers is to let out more chain. This may be all that is needed but assume it isn't. If you don't want/cannot use the dinghy then you will have to use the boat. after getting everything ready, motor as well as you can at about 90 degrees to the bower rode, estimating the same distance as you have chain out, and drop the kedge there. In practice this is remarkably difficult to judge and you may finish up with something very different from what you hoped. However, assuming that you have plenty of rode on both anchors, and that you have managed to drop the second anchor a reasonable distance from the first, you can usually adjust the rodes to achieve some sort of balance.

I prefer to use the dinghy. I always row the kedge out as rope rodes can tend to wrap themselves around outboard propellers and the engine is always in the way. Plus, putting the outboard on the dinghy and taking it off afterwards in these conditions is not easy. It is far easier to judge that the kedge rode is being laid at 60 to 90 degrees from the bower, bearing in mind that its angle is changing all the time due to yawing. The length of the kedge rode is marked, so I can be certain that I am laying out the same amount as on the bower. I have cleats on the outside of the dinghy transom, upon which I hang the anchor before starting. Once I have laid all the measured rope out, plus a little to allow for the anchor to slip a little, it is very easy to unhook the kedge and drop it into the water.

This method is tried and tested, but I do have a dinghy that rows fairly well and I practise a lot!
 
Normally I lay the second anchor by dingy. We have a rigid dingy that can be rowed in very windy conditions. I never use the outboard to lay a second anchor, because rowing gives much more control over the dingy. In severe winds I can row out the second anchor with the anchor hanging over the stern, the chain and rode are always ready for use from the bow ( In winter ) The rode is coiled in the bow sprit net, with the short chain on top of it to prevent accidental blowing of.
Second anchor ( Northill ) is ready on the bowsprit, secured with a “Cunning “ rope system. Can be lowered in the dingy in a second, even with dangerous waves.

However, a few times in winter an unexpected thunderstorm surprises us. In Med thunderstorms winds can pick up from zero to 50 knots in seconds and... from any direction. Whether forecasts are useless for thunderstorms.
In those situations even our dingy is useless. So … visibility non, except during the lightning bolts.
I start the engine, steer the boat at what I think is 45° of the main anchor ( In fact one does not know where the anchor is ) then engage the autopilot and give gas so the boat moves forward.
Our boat is long keeled, does what I expect it to do.
Then I crawl forward and when the main anchor chain makes eary noises, I tip the second anchor out of the bowsprit.
Running back, engine in neutral and look what happens. In all but one case the second anchor took all strain, I knew the main was still in deep.
Only once the Northill fouled itself in its chain and was useless. Pull the thing back up ( By hand ) and start over.
We had times that the only way to know if the anchors ware holding was the depth sounder. No lights in those desolate Turkish bays. No moon, no stars, just horizontal rigid rain and the wind making it impossible to hear the idling engine.
 
Neeves said:
Any yacht that veers sufficiently that it is too close to its neighbour has anchored to close in the first place.
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Sailors from counties that have uncrowded anchorages feel they have a right for a very large swinging circle. This does not happen in the more crowded anchorages of the world. If you anchor differently to your neighbours you need to consider the difference in swing circle. If you set two anchors in a V formation you swing circle will alter.

Neeves said:
Reading a whole host of anchor threads one thing does stand out - the reports of modern anchors dragging are notable by their absence.
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In strong wind boats unfortunately often drag. I wish it was not so. Many of these have "modern" anchors.

Neeves said:
One thing that causes any anchor, including modern ones, to drag is catching something in the toe, or fluke. In popular anchorages: Beer cans, old towel (we caught a gas cylinder once) in more isolated places: waterlogged wood, large piece of seaweed and whale bones.
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I have never dragged because on whale bones :), but setting the anchor also tests the anchor, which is one reason why it is such an important step.
 
Storyline said:
This is a bit like a 'how long is a piece of string' type post but having never set two anchors I am a total innocent so please be gentle ;)

The essence is, how far apart to lay each anchor and should the rodes be of similar length ?

Next season we will be in a position to set a V as we are getting a Fortress. Thinking through how I may deploy it, leads me to conclude it will have to be by using the mothership.

Of course, if we have advanced warning of a severe gale and are forced to stay where we are, the second anchor could be laid by dinghy.
Click to expand...

Our second main anchor is now a Fortress, which makes deploying by dinghy, in reasonable weather, very easy. It is a much more controlled. operation using the dinghy, because you know from the length of line, how far you are from the boat. You also have a fairly clear idea of the angle between the chain of the first rode, and the one you are rowing out.

However, life is not always straightforward and sometimes you can only drop the second anchor from the boat. Here one must have everything ready, and clear to go. I only use about 5m of heavy chain, and the rest nylon. I have the nylon all flaked out clear along the deck, with the anchor and chain, (and tripping line and buoy) all attached. It's then a case of motoring ahead, but to whichever side the anchor is to go, until you think (guess) that you are roughly as far ahead as the first anchor, but well out to the side, then let it go immediately. When the boat drops back you'll get a good idea of how the two anchors are sharing the load, and can let out more rope or chain as required. There's no hard and fast rules about all this, but I like to have my anchors at between 45º and about 60º to each other. The other consideration is whether the wind is expected to veer round, and what this will do to your anchor spread.

I think that you, like me, sail mostly on the West Coast, and while we do get some interesting weather at times, we are also blessed with some very sheltered anchorages, so that while you may have a lot of wind to contend with, you shouldn't have to worry about sea.

It is well worth practicing your anchor procedure, so that if things do get serious, you have a plan.
 
I have never dragged because on whale bones :), but setting the anchor also tests the anchor, which is one reason why it is such an important step.[/QUOTE]


In Refuge Cove, Wilsons Prom, tiny anchorage, the National Parks collected all the whale bones from the shore and dumped them in the middle of the bay. Whales regularly beach themselves in Tasmania, and other places, its practice to simply leave the bones where they are, return everything to nature. Some of these will end up in the sea. I watched the Australian Navy one day, all, well 3 or 4, of their deckchairs blew into the sea, they did not retrieve one of them.

Expect the unexpected.

But having all ones eggs in one basket?

Jonathan
 
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