How should I anchor?

[NormanS]

With a line ashore, what happens when the wind moves to be on the beam. Anchors resist inline pull well but not sideways. If the wind gets up isn't it more likely that your anchor will come unstuck if you have a line ashore than if you are swinging? If you anchor does loosen, it wont reset.

Of course I realise that a line ashore is preferable when there is not much room for swinging, but surely only when winds are light? I would point out that I too regularly sail in Greece. Taking a line ashore is not my favourite activity, but I do it ery occasionally!

Tudodrsailor

If your line from the shore is taken from the bow, the boat will lie head to wind. In effect a Bahamian Moor. In a real Bahamian Moor the line from the shore, or from a second anchor, should be made fast to the main rode, below the level of the keel.

 

[NormanS]

This one is addressed to all extreme snubber enthusiasts:- OK, you all believe that catenary completely disappears when the wind blows. You say that chain goes dead straight (which is impossible). What about the elasticity of your snubbers. Is it like Pinocchio's nose, and keeps on growing? What happens in extremis? Does it snap, so you're back to chain, or what?

 

[Adios]

35kg won’t produce much curve above 20 knots wind so yes, pretty insignificant. A snubber can be stretched quite a few time before losing it’s elasticity but I always think they are worth replacing after a serious prolonged blow.

Are we both agreed that 50m scope in 8m depth is enough? Lower angle maybe a bonus but leaving that aside its just to stop snubbing and that potentially causing damage or jerking the anchor free?

In the example its an additional 35kg of anchors PLUS 46kg more spare chain, so 81kg of weights, hung away from the ends on 116kg of chain. (assuming 10mm chain)

I didn't mean a snubber would loose elasticity over time, though good point to consider, but that once it is stretched out there is no more give so it will at some point be doing nothing if it hasn't snapped, the same as at some point a chum weight won't be doing much if the chain is permanently straight out. It also has an increasing load the closer to straight it gets same as elastic.

Out of curiosity I just did a little static pull test with a 2kg milk bottle in the middle of a meter of rope, close enough to equivalent weight and distance. I was pulling my balance scales to 6kg when it was half way lifted and 10kg before the rope was getting close to being straight. To get it "bar taught" and be at a point of loosing all snubbing effect would take more, but even at 5x the weight that's AT LEAST an additional pull equivalent to lifting 400kg straight up, required to get to the straight chain and no snubbing point, plus the 50m of chain is more so we're talking about a dead lift of around a 1000kg. I'm trying to imagine if the windage on the pointy bow of a 10ft wide hydro-dynamically ideal 35ft yacht can drag it back strongly enough for it to dead lift 1000kgs? I don't know how you'd compare that to the effect of your snubber vs the joules of a boat in motion etc but if you can prove it will have no significant effect from adding those weights I'd be pleased to see the working out and gladly be educated. When there is no snubber mentioned on the example boat though it will have to be really insignificant to not seem worth doing.

 

[RupertW]

Are we both agreed that 50m scope in 8m depth is enough? Lower angle maybe a bonus but leaving that aside its just to stop snubbing and that potentially causing damage or jerking the anchor free?

In the example its an additional 35kg of anchors PLUS 46kg more spare chain, so 81kg of weights, hung away from the ends on 116kg of chain. (assuming 10mm chain)

I didn't mean a snubber would loose elasticity over time, though good point to consider, but that once it is stretched out there is no more give so it will at some point be doing nothing if it hasn't snapped, the same as at some point a chum weight won't be doing much if the chain is permanently straight out. It also has an increasing load the closer to straight it gets same as elastic.

Out of curiosity I just did a little static pull test with a 2kg milk bottle in the middle of a meter of rope, close enough to equivalent weight and distance. I was pulling my balance scales to 6kg when it was half way lifted and 10kg before the rope was getting close to being straight. To get it "bar taught" and be at a point of loosing all snubbing effect would take more, but even at 5x the weight that's AT LEAST an additional pull equivalent to lifting 400kg straight up, required to get to the straight chain and no snubbing point, plus the 50m of chain is more so we're talking about a dead lift of around a 1000kg. I'm trying to imagine if the windage on the pointy bow of a 10ft wide hydro-dynamically ideal 35ft yacht can drag it back strongly enough for it to dead lift 1000kgs? I don't know how you'd compare that to the effect of your snubber vs the joules of a boat in motion etc but if you can prove it will have no significant effect from adding those weights I'd be pleased to see the working out and gladly be educated. When there is no snubber mentioned on the example boat though it will have to be really insignificant to not seem worth doing.

I did do the catenary curve calculation a few years ago as I was a fan of heavy chain before realising that the maths (and then experience from snorkelling) showed that weight just doesn’t help snatch forces in any noticeable way. The issue isn’t whether there is any curve left in the rode but whether there is so little that it would take an extraordinary force to allow even a few centimetres of further stretch let alone the ideal metre or two to dampen the force that could cause an anchor drag.

So in your example you have encountered the increasing force needed for each further centimetre of curve straightening which means that the wind speed needed moves up towards infinite for each extra centimetre. This is the opposite of what you want and basically means that the chain even with weight is bar taut even with a tiny bit of curve left as the forces required to straighten it further are too high to exist in the real world. There is no point in a tiny visible curve to the chain if that can’t be straightened by a gust.

 

[Adios]

I did do the catenary curve calculation a few years ago as I was a fan of heavy chain before realising that the maths (and then experience from snorkelling) showed that weight just doesn’t help snatch forces in any noticeable way.

It must do if there is enough of it for the situation. But Chain which is spread out to both ends where there is little more than its own weight to lift will give less benefit than a weight suspended in the middle of the scope. Did you try a chum weight to see what that did? On small boats I chuck one on and the line is up and down, gives a nice smooth motion as it is lifted. If lifts too quickly and hangs there then there's not enough weight. But it does have the potential to work I'm sure of that on different scales.

The issue isn’t whether there is any curve left in the rode but whether there is so little that it would take an extraordinary force to allow even a few centimetres of further stretch let alone the ideal metre or two to dampen the force that could cause an anchor drag.

So in your example you have encountered the increasing force needed for each further centimetre of curve straightening which means that the wind speed needed moves up towards infinite for each extra centimetre. This is the opposite of what you want and basically means that the chain even with weight is bar taut even with a tiny bit of curve left as the forces required to straighten it further are too high to exist in the real world. There is no point in a tiny visible curve to the chain if that can’t be straightened by a gust.

yes 100% agree with all that but it applies equally to chum weights and the elastic in a snubber. But do you know how to compare a given snubber with a given chum weight? I started trying to work it out but lost the will to live.

I guess at least with adding weights you can have more or less depending on the conditions. If a snubber was sufficiently stiff and resistant to stretching right out for a good blow it wouldn't be as suitable for moderate conditions.

 

[Stemar]

This one is addressed to all extreme snubber enthusiasts:- OK, you all believe that catenary completely disappears when the wind blows. You say that chain goes dead straight (which is impossible). What about the elasticity of your snubbers. Is it like Pinocchio's nose, and keeps on growing? What happens in extremis? Does it snap, so you're back to chain, or what?

In extremis, it absorbs the shock load, reducing it considerably. I don't expect my snubber to reduce the constant load, but to manage the shock loads when the boat snatches at the chain because of a gust or wave motion. It also pretty much does away with the graunching noise as the chain moves in the roller fitting, which is why I still use it in calm conditions

 

[RupertW]

It must do if there is enough of it for the situation. But Chain which is spread out to both ends where there is little more than its own weight to lift will give less benefit than a weight suspended in the middle of the scope. Did you try a chum weight to see what that did? On small boats I chuck one on and the line is up and down, gives a nice smooth motion as it is lifted. If lifts too quickly and hangs there then there's not enough weight. But it does have the potential to work I'm sure of that on different scales.

yes 100% agree with all that but it applies equally to chum weights and the elastic in a snubber. But do you know how to compare a given snubber with a given chum weight? I started trying to work it out but lost the will to live.

I guess at least with adding weights you can have more or less depending on the conditions. If a snubber was sufficiently stiff and resistant to stretching right out for a good blow it wouldn't be as suitable for moderate conditions.

I don’t think we will convince each other on the chum weight ineffectiveness without the maths so I must look up the calcs. But a stretch snubber has completely different characteristics as a strong force becomes a stronger one. A chum/chainweight will require massive forces to stretch even a small amount once under a decent load but a snubber does not have that steep expontial curve versus stretch distance.

Regarding what snubber to have that will work in moderate and in strong conditions I think you need at least two parallel stretch types ideally one which will reduce small snatch loads in ok conditions and a much stronger longer one for severe. For me that is a 40m nylon 14mm rode for the strong conditions and a big dogbone rubber snubber at the chain hook end for 90% of the time. In extreme conditions the dogbone will be completely stretched out and I see that as sacrificial but they usually last a year or two before giving up in a real blow.

 

[geem]

In wind over tide situations my boat sometimes sails up the chain and the snubber drops off when it goes slack. What is the best way to deal with this issue?

We attach a 100mm diameter fish-pot float to the chain hook with 300mm of light line. It keeps the hook connected to the chain. Simples. We use ours when the snubber/chain hook touches the seabed in light/zero wind

 

[Adios]

I don’t think we will convince each other on the chum weight ineffectiveness without the maths so I must look up the calcs. But a stretch snubber has completely different characteristics as a strong force becomes a stronger one. A chum/chainweight will require massive forces to stretch even a small amount once under a decent load but a snubber does not have that steep expontial curve versus stretch distance.

Well that's why we do science! Pretty crude equipment but you seem to be right the increase has an exponential curve.

With a bend in the rope of 120 degrees or less it is 2kg
130 degrees - 2.5kg
140 degrees - 3kg
160 degrees - 10kg
I would guess 165 degrees 20kg but my kid couldn't measure it quickly enough for my fingers. To get it straight would be massive considering its only a 2kg weight.

How that translates to distance is roughly 4.5% increase from 140 to 160 degrees and around 6% if 170 degrees is achieved. Over 50m of chain that's from less than 2 and a half to 3 meters of expansion and contraction, not very much compared to a wave length if waves were a factor in the position the boat was in, but its not nothing. If the actual hanging weight was significant and close to what was exerted on the boat it could be ok still but the initial weight would need to be a lot more than i realised. I guess there is some data out there on how much force a given wind puts on a boat at anchor but that 81kgs doesn't seem so much now.

I guess surging backwards and forwards could be an issue with snubbers more than weights but seeing the physics of weights like this definitely makes me think something with a more even elasticity would be better for serious needs.

 

[geem]

If Thinwater comes along he may comment.

He tried in line tandem anchoring.

First off its difficult to set 2 anchors in line connected together. Secondly if the furthest anchor holds then as the rode tightens, or straightens it results in a vertical component on the inner anchor (the one nearer the yacht) and simply lifts it out. You then have one anchor holding the yacht and the other simply acting as a kellet. Finally its difficult to retrieve two anchors joined together in line.

If you know the wind is going to be 'fairly' constant you could deploy and set two anchors on 2 independent rodes roughly next to each other. If the rodes are very similar, so same chain size, same length then they will perform similarly and you will have twice the hold of one anchor (assuming the 2 anchors are the same design). However though using a high holding anchor offers advantages (they also seem to resist veering better - though quantifying this advantage has so far defeated - everyone) it is not an absence of hold that is the issue.

There is some other mechanism that allows anchors to drag - in the absence of another idea I'm putting my money on the the movement of the yacht causing twitching at the anchor and this resulting in a lowering of shear strength of the seabed and thus lowering actual hold. So my focus is on keeping the yachts movement to a minimum and introducing elasticity to the rode (which absorbs energy, snatch loads and introduces a part of the rode that does not transmit so well the yachts movement to the anchor and seabed).

An idea to bear in mind - Morgans Cloud removed their recommendations for concave anchors ( or those like Rocna and Supreme), but continue to use a Spade as their primary. The implication is that despite the high hold of a Rocna (twice that of a Delta).........

they still dragged.


An experiment, like my cement and trowel experiment above. Take a bit of anchor chain and string it between 2 trees, does not matter if its tight or droopy, but not touching the ground. Have your finger touching one end (and stretch your imagination and pretend your finger is an anchor). Now (you have proven you have a good imagination so now assume that a hammer or mallet is like a yacht!) have someone hit the other end with a hammer, even a rubber mallet. You will feel the impact - no matter how long the chain. Now attach one end with your nylon snubber and repeat hitting the snubber with the same hammer/mallet. The impact is dampened. Same as your anchor. Chain is a, almost, perfect transmitter of movement - so every sea saw of your yacht every gentle straightening of your chain is immediately transferred to your anchor (unless you use a decent snubber).

Using elasticity and catenary to minimise movement and snatch loads is not very clever. Your car uses a variety of mechanisms to smooth out bumps, shock absorbers, springs, tyres, foam in the upholstery - the idea that catenary can do everything does seem a bit simplistic - especially as we have other mechanisms available to us. A snubber does not work by itself, catenary is still there.

Jonathan

I think I have mentioned this before on the forum. We have successfully used two anchors on separate rodes in winds over 40kts. The wind was veering through 90 deg due to a hill immediately in front of the anchorage. The wind would come from one side of the hill then the other. Lots of boats veering around dramatically. We set the main Spade anchor as normal on chain with a 12m snubber but then add a second lightweight aluminium anchor via the dinghy. The second anchor was set in a Y format in relation to the main anchor. The rode is all rope. No chain. We tighten the rope rode so the boat is predominately lying to this anchor. The effect of the stretchy rope on the boat is instantly noticeable. More comfortable and a lot less veering.

 

[Neeves]

This one is addressed to all extreme snubber enthusiasts:- OK, you all believe that catenary completely disappears when the wind blows. You say that chain goes dead straight (which is impossible). What about the elasticity of your snubbers. Is it like Pinocchio's nose, and keeps on growing? What happens in extremis? Does it snap, so you're back to chain, or what?

It snaps.

Which is why you need a long one, they are less prone to snapping and/or you deploy a storm snubber (instead of more chain that you don't have)

Snubbers are like sheets, batteries or chain - they wear out. Their life is a function of the number and size of stretch cycles. But it is impossible to measure these cycles and you either retire the snubber to a schedule, or wait till they fail. We have had 2 fail, both old and short ones of 3 ply. You do know when they fail - the sound is similar to a gun shot. Because they fail you should always have a chain lock, of some sort (and spare snubber).

At about 30 knots with a 5:1 scope and 6m between bow roller and seabed your rode will 'look' straight (it obviously is not straight) but the effective catenary left is basically zero (see graph). You can obviously deploy more chain (or bigger chain ) but there may not be any room behind you to deploy more chain (in a crowded anchorage - another yacht or 3). If you added a snubber it has a similar energy managing capability as chain, upto 30 knots (see graph) but will continue to work until it fails.

Check the graphs in this article (scroll through the pictures at the top of the article): There is also a picture of a simple lock for a chain hook.

The art of snubbing, in the nicest possible way - MySailing.com.au

If you read the article on the Med storm you will note they were attempting to add a storm snubber, but the original chain hook failed, they did not have a chain lock, all the rode discharged (the clutch slipped) - so they had plenty of chain deployed and their anchor, CQR, held.

and if still in doubt - ask another question.

Note also Geems comment, post 50, on a long sketchy rode (a long snubber would have the same effect).

If the idea of having a spare snubber, or an extra snubber or the idea that snubbers are sacrificial upsets you - do go to the climbing gym and recycle their retired ropes. They otherwise go to landfill (and I guess last centuries). Retired ropes have no value, cannot be sold, cannot be used for height safety and have no known other uses. Do you bit for the environment and put them to good use. If you feel bad about begging an old rope - offer to refill the coffee fund for them.

Frankly I can see no reason NOT to carry a bit of climbing rope (make good mooring lines as well). Frankly I can see no reason not to at least try a bit of perfectly good rope and try it as a snubber - you are then in a better educated position to argue against them

Jonathan

 

[NormanS]

It snaps.

Which is why you need a long one, they are less prone to snapping and/or you deploy a storm snubber (instead of more chain that you don't have)

Snubbers are like sheets, batteries or chain - they wear out. Their life is a function of the number and size of stretch cycles. But it is impossible to measure these cycles and you either retire the snubber to a schedule, or wait till they fail. We have had 2 fail, both old and short ones of 3 ply. You do know when they fail - the sound is similar to a gun shot. Because they fail you should always have a chain lock, of some sort (and spare snubber).

At about 30 knots with a 5:1 scope and 6m between bow roller and seabed your rode will 'look' straight (it obviously is not straight) but the effective catenary left is basically zero (see graph). You can obviously deploy more chain (or bigger chain ) but there may not be any room behind you to deploy more chain (in a crowded anchorage - another yacht or 3). If you added a snubber it has a similar energy managing capability as chain, upto 30 knots (see graph) but will continue to work until it fails.

Check the graphs in this article (scroll through the pictures at the top of the article): There is also a picture of a simple lock for a chain hook.

The art of snubbing, in the nicest possible way - MySailing.com.au

If you read the article on the Med storm you will note they were attempting to add a storm snubber, but the original chain hook failed, they did not have a chain lock, all the rode discharged (the clutch slipped) - so they had plenty of chain deployed and their anchor, CQR, held.

and if still in doubt - ask another question.

Jonathan

Come on now Jonathan. At one point above you say that there might not be room to let out more chain, and yet you're advocating adding a snubber!
Chain is wonderful stuff. It lasts for years and years. ?

 

[Neeves]

Come on now Jonathan. At one point above you say that there might not be room to let out more chain, and yet you're advocating adding a snubber!
Chain is wonderful stuff. It lasts for years and years. ?

I have offered access to a pdf in which I use a 2 x 30m snubber yet only 10m of that snubber is forward of the bow. No-one has taken up the offer of access to the pdf. I can deploy 15m of each arm of our bridle and have none forward of the bow. Check the 'value' of a snubber vs deployment of 10m of chain in the graphs. In low wind speeds chain and nylon are roughly 'equal' as the catenary straightens catenary diminishes in value (to zero). Nylon continues to work, until it fails, or is near failure) and if you use skills that anyone who owns a yacht has - you can deploy as much nylon as you can carry without it needing more sea room (just set it up as a block and tackle system).

Its amazing the number of people who re-galvanise their chain

Jonathan

 

[Neeves]

I think I have mentioned this before on the forum. We have successfully used two anchors on separate rodes in winds over 40kts. The wind was veering through 90 deg due to a hill immediately in front of the anchorage. The wind would come from one side of the hill then the other. Lots of boats veering around dramatically. We set the main Spade anchor as normal on chain with a 12m snubber but then add a second lightweight aluminium anchor via the dinghy. The second anchor was set in a Y format in relation to the main anchor. The rode is all rope. No chain. We tighten the rope rode so the boat is predominately lying to this anchor. The effect of the stretchy rope on the boat is instantly noticeable. More comfortable and a lot less veering.

We have a similar practice and deploy a second anchor when the forecast in the anchorage is going to be 35 knots plus (so compared to Geem's 40 knots - call me a wimp!) Our second rode is 15m of 6mm high tensile chain and 40m of 3 ply 12mm nylon. Our primary anchor is aluminium, an Excel weighing 8kg and our spare anchors are also aluminium, Spade A80 and 2 x Fortress (FX16 and FX 37, the latter for squishy mud). We would also deploy from a dinghy. Our primary rode is 6mm HT chain, 75m and we use 30m x 10mm snubbers, 2 off, as a bridle. Our yacht is a 38' catamaran which has the windage of a 45' AWB.

When we are anchoring long term, a few days, and the weather might be challenging we place our second rode on deck (its stored neatly in a milk crate), with the anchor appropriate for the seabed. Each of our 'spare' anchors already has its own shackle already attached. If we feel twitchy, 35 knots, - we are ready and able for a quick deployment. The FX16 is ideal in clean sand, the Spade ideal in weedy bottoms and those with stones pebbles and shells. (If you are 'sharp' and you look at some of the pics of our catamaran you can sometimes see the milk crate and the yellow on the fluke of the Spade in some of the images).

If your yacht is yawing, because of its characteristics, or because of the 'geography' of the anchorage (see Geem's post) then sitting on one anchor and aggressively veering may unseat your anchor (because it is being constantly tensioned at opposing angles). One common advice would be - use a big anchor. Sadly a big anchor will set less deeply that a smaller one, under the same tension - I wonder if anyone considers that the big anchor is less stable than the smaller one given that its shank will have a larger lever arm effect - every time it is tensioned at an angle??? We far prefer 2 smaller anchors each set for the maximum tension angle (which they will automatically adjust to themselves). Because a Mantus sets shallow (and the lever arm effect greater and it 'sets' in the less consolidated upper layers of the seabed) I cannot ever commend it, at all. If you like the Mantus concept - buy a Viking.

Setting a second anchor from a dinghy can be a bit of a faff - what else are you actually doing as you wait for the wind to increase?

Jonathan

 

[Roberto]

wind speeds of over 100kts

I'd definitely figure a way to anchor the boat the way you most like, then immediately go ashore to seek personal shelter.
With 100kt (real 100kt) wind you won't be able to do anything meaningful on the boat, just risk your life.

 

[Neeves]

I'd definitely figure a way to anchor the boat the way you most like, then immediately go ashore to seek personal shelter.
With 100kt (real 100kt) wind you won't be able to do anything meaningful on the boat, just risk your life.

I agree, and at lower wind speeds.

I read surprisingly often

'I/we have sat out 2 named storms'.....'and our (insert name) anchor held us firm.

I wonder about these people - they really sat out exposed to the fury of a named storm - their sanity and credibility (to me) is low.

We sat out, unnamed, 70 knots in Tasmania. We found the most sheltered location available and the wind was never more than 20 knots. So yes - we sat out a forecast 70 knot storm - so what.

Sounds great as bragging rights, if that's what turns you on - its not a competition. Sailing is meant to be a pleasure not part of an SAS course. You equally have no right to test the courage of your crew nor the availability of divorce lawyers.

Jonathan

 

[Fascadale]

Jonathan

In your "Art of Snubbing" article you say "Chain on the seabed has the advantage of friction between chain and seabed. So chain on the seabed reduces the impact of chain on anchor". If I understand this correctly you are saying that this reduced impact decreases the movement/vibration of the anchor in the substrate, thus reducing the liquefaction of the substrate and thus increasing the anchor's holding.

This takes me back to "tandem anchoring". Would it not be the case, if tandem anchored, that the anchor nearer the boat, if it were on the seabed, would create the friction that you refer to in your article?

In the YouTube below they shackle on the number two anchor about two metres closer to the boat than the primary anchor. (About minute 15) It also appears that when quite a lot of power is applied astern the chain stretches diagonally taut from the closer anchor leaving the chain to the primary on the seabed. Increased friction? Better holding?

 

[Neeves]

Jonathan

In your "Art of Snubbing" article you say "Chain on the seabed has the advantage of friction between chain and seabed. So chain on the seabed reduces the impact of chain on anchor". If I understand this correctly you are saying that this reduced impact decreases the movement/vibration of the anchor in the substrate, thus reducing the liquefaction of the substrate and thus increasing the anchor's holding.

This takes me back to "tandem anchoring". Would it not be the case, if tandem anchored, that the anchor nearer the boat, if it were on the seabed, would create the friction that you refer to in your article?

In the YouTube below they shackle on the number two anchor about two metres closer to the boat than the primary anchor. (About minute 15) It also appears that when quite a lot of power is applied astern the chain stretches diagonally taut from the closer anchor leaving the chain to the primary on the seabed. Increased friction? Better holding?

This is Thinwater's Practical Sailor article

Doubling Up: Full-size Tandem Anchoring - Practical Sailor

As a contributor I enjoy free access. If the article for you is behind a pay wall let me know and we'll figure a way of you having access.

There is a technique of tandem anchoring (and from memory it is, or was, part of the Royal Navy's seamanship practices) to deploy and set the primary anchor then deploy a second anchor such that it simply drags on the seabed (I think they confusingly call it a Hammerlock). I don't recall that this second anchor is actually attached to the set primary rode, at all. The second anchor is simply there to act as a 'sort of' friction brake - it simply drags on the seabed, with insufficient scope to set and thus 'manipulates' or dampens yawing. It is better than a kellet, which tend to be regularly shaped (if you believe in kellets/chums (which I don't) you want to make it like a hedgehog or WWII mine.

The idea of tandem anchoring is to offer increased hold using both anchors as, anchors. The motivation being if you have 2 anchors you have twice the hold. The reality is that this is not the case, as the anchor nearest the yacht simply lifts out of the seabed. Yes this will be better than simply having one anchor set but it would be similar to deploying more rode in the first place. If your anchors weighs, say, 15kg that would only be a few metres of chain it easier to deploy more chain than deploy (and retrieve) 2 anchors chained together. I would accept that if you have limited space the idea has merit (though I'd prefer two independent rodes (for which you should be geared up), short length of chain, second anchor, sheets and mooring lines tied together etc. Even better always carry a spare rode (mixed, chain and rope) and you really should have a spare anchor (its surprising how many primary anchors are lost).

Seabed friction is interesting, depends how bored you are , but if you lay a length of rode on wet sand, or in shallow water, it is quite easy to pull in a straight-line and once you get it moving its even easier. So if your anchor trips and is dragged as soon as it moves the chain does not offer much resistance. If you try to drag the same chain sideways - so deploy your length in a straight-line - now try to drag it sideways - it is very very difficult and becomes increasingly difficult the more you are trying to drag (obviously). So as long as you have chain on the seabed, even better if it is is buried then the chain will reduce the impact of yawing (and twitching). I have never tried a hammerlock, nor a tandem arrangement but we do deploy 2 anchors in a 'V' and we do use shore lines.

Note all our anchors are alloy (aluminium) - we believe anchors work by design, not weight. But we use our anchors as anchors.

I did make a chum, melted roofing lead in a rum baba tin. This gave me 2 half doughnuts which I melted together making a whole doughnut. I did try it and then modified it, I drilled and tapped not and set into it M12 bolts, like my hedgehog. It does work but 2 anchors simply work much better. The hedgehog had one role and was quite heavy whereas extra anchors have a multitude of roles, replace lost primary, kedging etc. If anyone wants to pay for a 10kg lead hedgehog to be airfreighted to their chosen destination - its yours!

Jonathan

 

[NormanS]

I agree, and at lower wind speeds.

I read surprisingly often

'I/we have sat out 2 named storms'.....'and our (insert name) anchor held us firm.

I wonder about these people - they really sat out exposed to the fury of a named storm - their sanity and credibility (to me) is low.

We sat out, unnamed, 70 knots in Tasmania. We found the most sheltered location available and the wind was never more than 20 knots. So yes - we sat out a forecast 70 knot storm - so what.

Sounds great as bragging rights, if that's what turns you on - its not a competition. Sailing is meant to be a pleasure not part of an SAS course. You equally have no right to test the courage of your crew nor the availability of divorce lawyers.

Jonathan

Jonathan, it's nothing to do with bragging rights, but you may be correct about sanity. What same person would subject themselves to the rigours of sailing?
As you know, we sail in Hebridean waters, where we are blessed with innumerable sheltered anchorages. While many of these anchorages are completely sheltered from the sea, there is not necessarily any shelter from the wind. Sometimes the "shelter" provided by higher land to windward is worse than useless, as the wind then comes in accelerated gusts from varying directions. We often find that low-lying land to windward, while not reducing wind speed, gives a much steadier experience.
I don't think it is helpful to condemn and castigate people who have no realistic alternative to being anchored in storm force winds. Just count yourself lucky that due to topography and vegetation, you have shelter from the wind.

 

[geem]

Come on now Jonathan. At one point above you say that there might not be room to let out more chain, and yet you're advocating adding a snubber!
Chain is wonderful stuff. It lasts for years and years. ?

If you are so uncertain of the benefits of a snubber try bungee jumping off a bridge with your favourite chain. That should convince you?