a lunch anchor?

[vyv_cox]

Vyv, are you suggesting that a Rocna that has plowed a trench and piled up sand ahead of it is not well set or just that it was difficult getting it to set ?

I am used to seeing the Rocna set in its own length, with a scar maybe 40 cm or not much more. In the case of the Amorgos episode we knew it was dragging as we were trying to set it, chain bouncing and transits moving, but I persevered because I was expecting this to be a difficult place. I was using more chain than normal, maybe 35 metres in around 5 - 6 metres depth for the same reason. Eventually we held and I increased revs more than I would normally. Once I swam to it I could see that the scar was maybe 10 metres and the anchor was largely on the surface as shown previously, with a mixture of sand and weed in a pile ahead of it.

Jonathan's question re the June anchoring - my Rocna is 15 kg. One of the other boats is a HR34 known to us, Bugel about the same size as ours. The other two boats were rather bigger, so I suspect their anchors were also. The Delta was barely set at all, lying on the surface. They made no attempt to reverse it in and very quickly after anchoring swam ashore with their dog and walked along the beach. Brave indeed.

 

[J Neeves]

Vyv,

Ignorance is bliss.

I confess our anchors (and we have a fair cross section) sometimes do not set, at all. And like you we expect them to set - immediately. The major issue is thick weed with no sand patches, or at least none visible. We do not carry a fisherman's nor Marsh and would not want to carry a conventional anchor of a size that 'might' work in thick weed. We would simply move, whatever distance it takes, to find some sand or something with security.

But we would not leave the yacht if it was not secure (if we were ignorant we would have walked so many more beaches).

Vyv, but size was not a factor - you were just in the wrong place, but maybe by only 1m or 20m? Seabeds are a bit of a lottery.

Jonathan

 

[Storyline]

.....
.....
They made no attempt to reverse it in and very quickly after anchoring swam ashore with their dog and walked along the beach. Brave indeed

Vyv, you have a generous spirit, many people would say stupid, not brave

 

[Bloomy]

Noelex

When you read the last three pages of “Real world Experiences “ pages 9 to 11-- you will hopefully get the gist of what some, including myself have been saying, your photos are great, your experience is unquestionable, unfortunately your knowledge in anchor technology as to how they work, I have said this before- is far from mark, this is the problem when you try and make unrealistic comparisons by guessing, observations with an anchor sizing that is huge in comparison of the various designs of possible lighter designs.

Your input has been very good as your assumptions have been put to the test, quantified by real world experience, a good anchor as you put will not heap up the substrate, not true, listing is another down side so you say, not true, listing is encouraged in many designs for reasons explained in post 81 –padge 9

None of what you say other than new generation anchors are an improvement can be quantified by your photo’s unless it is all an apples to apples comparisons, you say look at my photos, then you be the judge, well fair enough but when I made comment as to how I saw the performance of the Ultra being due to a weed ball, you then came back and did not stand by your quote: you be the judge statement, you further went on to persuade- disagree with me.

Noelex I have spent many, many hours in anchor technology involved with the Monash University students, ANCHORS ARE NOT JUST ANCHORS, you cannot just make assumptions based on what you see.

The following posted by LadyInbed,

I am one who only uses moderate revs to straighten out the 8mm chain (always 5xD and 20m minimum) and set my over size Delta.
I hold it on those revs whilst watching that a transit doesn't change, then shut the engine down, put an anchor wp on the plotter, have dinner and a good nights sleep.
Should I worry more?
End Quote:

Noelex,

just what if some of those Deltas you photographed had of been the same weight as your huge Mantus, just maybe you would have experienced-- been able to shoot some great shots of a Delta really getting down and dirty instead calling poor sets typical of Deltas.

Anyway once again Noelex thank you for your great experiment on how not to judge anchor performance, possibly why you could not answer some of my more technical questions, it has been an Eye opener, Oh one other thing, the link to the anchors, http://www.sailnet.com/forums/seaman...ng-woes-4.html Rocna , Mantus, Manson excetra, thanks for that, what does stand out is the Mantus has a longer shank, it is also quite a lot thinner than all of the new gen, further observation is that the fluke seems to have a larger holding area, this doesn’t compute, why the shank so long, thin, more load, more leverage, rather odd-- no wonder the shank on your Mantus yielded in light conditions.

It would want to match at least the Rocna profile strength at least if I wanted one.
Any way as an example you could take a page out of MAIN SALES anchor testing methods, very interesting and closer to the mark.
Regards John.

 

[noelex]

Noelex - Not everyone anchors in gin clear water with a sand seabed. As an undoubted expert possibly you can introduce some balance and instead of continuing to ignore questions regarding the performance of your favourites maybe you can introduce some balance and comment on Morgan Cloud's fears and the Chesapeake Testing where comments are being raised over clogging of roll bar anchors and the total inability to set in a thin mud seabed. There are a number of people reading and contributing to this thread who have roll bar anchors and have even been persuaded to upgrade - one would think offering a broad view of performance would be valuable. In fact to continue to ignore the issue looks questionable.

I am not sure why you want me talk about mud. It is the one substrate that I have not encountered since getting the camera. I have no photos to provide some objective evidence to back up my opinions. Some of my winter anchorages are mud so I will have some photos if you can be patient and wait a few months.

However, here are my thoughts on anchor "clogging":

Anchors that drag, or take a long time to set, pick up a lot of debris. Anchors can pick up enough weed or sticky mud to inhibit their performance. This is dragged along by the fluke on the bottom. Convex anchors tend to shed most of this weed/mud as they are raised. Concave anchors do not not. What is important is not the anchor appearance when raised to the surface, but what is happening on the bottom.

This is an example of weed and is the best I can do photo wise to illustrate the problem. This Delta was very "clogged" with weed but was almost clean when raised to the surface. Most of this weed that is wrapped around the fluke is not growing. It has been pulled out as the Delta dragged through the weed in an attempt to set. The fluke is not visible.

Nice flower arrangement

This was the anchor as it broke the surface. A concave anchor would have carried much more of this garbage to the surface even if it looked identical on the bottom. It would be easy to assume this convex plough anchor was not "clogged" with weed when in reality, on the seabed, where it counts, it was.

The secret to reducing "clogging" whether in weed or mud is to have an anchor that sets very quickly, can change direction without breaking out and finally of course one that does not drag. If the anchor is not moving it is not "clogging".

Have a look at my photos and see which anchors set quickest and rotate in manner that is less likely to break out.


There is no doubt in mud the pivoting fluke anchors like the Fortress, Danforth and Brittany have the best holding power in mud. In very soft mud the Fortress set at 45 degrees is an exceptional performer.

However, these are not great general purpose anchors and there are occasional problems with these anchors breaking out with a substantial change in direction of pull.

Most mud is quite an easy substrate. Blade surface area together with the blade design are more important factors. There is less need for a clever design that can cut into the substrate. In my experience the concave roll bar anchors with their large blade area and concave fluke are good performers, but so are many other designs of anchors such as the concave non roll bar anchors such as the Spade.

I am not keen on convex plough (fixed or articulated) anchors in most mud situations. The limited blade area for the anchor weight and lower resistance of convex shape means they are poor performers in my view. They often do a slow drag, creeping backwards. However, if the mud has a firmer base layer these anchors can work OK.

The exception with mud is the very soft soupy mud. This is a difficult substrate where it often takes multiple tries to get the anchor to set and even then the holding power is very limited. I notice you have asked me to comment on the recent Chesapeake Bay tests. Fortress are to be encouraged for running what would have been an expensive test. Unfortunately the spread of results in this test was very high, so we should be carefully drawing too many specific conclusions. This is one of difficulties testing in this sort of substrate.

Even the Fortress failed to set in one of its five pulls both at 32 and 45 degrees. Nevertheless the Fortress results at 45 degrees were much better than any anchor, as I would expect. However, even the holding power of this anchor was very low (due to the substrate not the anchor) and not suitable for overnight unless you were very sure of the forecast or had a Fortress set to 45 degrees that was considerably oversized.


I hope that answers your questions.

 

[Brian@Fortress]

Most mud is quite an easy substrate. Blade surface area together with the blade design are more important factors. There is less need for a clever design that can cut into the substrate. In my experience the concave roll bar anchors with their large blade area and concave fluke are good performers, but so are many other designs of anchors such as the concave non roll bar anchors such as the Spade.

I am not keen on convex plough (fixed or articulated) anchors in most mud situations. The limited blade area for the anchor weight and lower resistance of convex shape means they are poor performers in my view. They often do a slow drag, creeping backwards. However, if the mud has a firmer base layer these anchors can work OK.

The exception with mud is the very soft soupy mud. This is a difficult substrate where it often takes multiple tries to get the anchor to set and even then the holding power is very limited. I notice you have asked me to comment on the recent Chesapeake Bay tests. Fortress are to be encouraged for running what would have been an expensive test. Unfortunately the spread of results in this test was very high, so we should be carefully drawing too many specific conclusions. This is one of difficulties testing in this sort of substrate.

Even the Fortress failed to set in one of its five pulls both at 32 and 45 degrees. Nevertheless the Fortress results at 45 degrees were much better than any anchor, as I would expect. However, even the holding power of this anchor was very low (due to the substrate not the anchor) and not suitable for overnight unless you were very sure of the forecast or had a Fortress set to 45 degrees that was considerably oversized.

In soft mud we recommend initially setting the Fortress at a very short scope (ex. 2:1 or 3:1), as this should prevent the shank from sinking below the flukes, and I think this is good advice for any "pivoting-fluke" type of anchor. The Chesapeake Bay test protocol called for a payout of 5:1 scope + 100 ft (30 m), resulting in a starting scope of about 8.3:1, and then using the aft winch, pull back the 100 ft (30 m) at a rate of 10 ft (3 m) per minute, so each anchor was given a full 10 minutes to engage the soft mud bottom and develop resistance (or not.)

So with this test protocol we were, in essence, ignoring our own advice in our "Safe Anchoring Guide."



We noticed that some of the other anchors were failing to set as well, and after all anchors were tested 4 times over 3 days, we devoted the last day to trying a new protocol, which called for us to pay out about a 2:1 scope, and then pull in 20 feet (6 m) at 30 feet (10 m) per minute, or until we developed a load of 200-300 lbs (91-136 kg), and then start the test as we had done previously.

We thought we might learn something that could improve setting performance in soft mud, which we then could pass along to owners of the other anchors in this test.

For the most part, the "new generation" anchors did not distinguish themselves as better performers than the "old generation" models in this soft mud bottom. In fact, a serious concern was raised as to whether a new generation anchor would be able to orient itself, either at all or even slightly, if it landed on its side or upside down. Although we could not see the anchors, it seemed possible that the mud provided too little resistance for these anchors to correctly orient themselves in an upright position.

Among the roll bar models, the Rocna was particularly (and inexplicably) prone to not setting and developing resistance.

To calibrate what we observed with anchors that would not set, we "tested" a lead weight of approximately 45 lbs (20 kg) to measure its resistance when connected to the chain and wire rope. Interestingly, it developed about the same resistance as several of the 44-46 lb (20-21 kg) anchors we tested, which was about 130 lbs (59 kg).

 

[noelex]

Brian I think Fortress should be congratulated for testing the anchors on a universal setting protocol rather than something specific for Fortress.

As an aside (and sorry this thread has rather drifted off topic) there has been some suggestion on this forum that it is "the chain that holds the boat" rather than the anchor. I think you did some baseline tests to determine the holding capacity of the chain alone (with no anchor, or weight) I imagine this was very low, but if you could quantify this together with the chain specifications it might help dispel the myth that that it is chain rather than the anchor doing the work. This sometimes confuses anchor threads and it would be great to dispel this myth.

 

[onesea]

I am one who only uses moderate revs to straighten out the 8mm chain (always 5xD and 20m minimum) and set my over size Delta.
I hold it on those revs whilst watching that a transit doesn't change, then shut the engine down, put an anchor wp on the plotter, have dinner and a good nights sleep.
Should I worry more?
PS this has dragged a long way from a Lunchtime Anchor!

No I do worse than that, I throw my anchor over the bow when I am as 2-3 times water depth I wait to be brought up. Then through rest of scope is dropped over side if there's weather I will check to be brought up again if not I just go ashore. Enjoying seeing the pictures (would like to see some of a danforth as its the one I like) keep them coming, what evidence can be drawn form them could be debatable.

I have never been keen on ploughs, but that's just me.. Also never been keen on digging anchors in too hard they are only harder to pull out and if there is weather they should dig themselves in... If they don't its time to go sailing :ambivalence:.
As some one raised earlier if the winds from the SW and the forecast is from the NE there is no pint digging it in the wrong way, if its going to work it will find its own set sooner hopefully rather than later...

Ignorance is bliss.

Hence I have had many a happy and merry night in bliss!

 

[Brian@Fortress]

Brian I think Fortress should be congratulated for testing the anchors on a universal setting protocol rather than something specific for Fortress.

As an aside (and sorry this thread has rather drifted off topic) there has been some suggestion on this forum that it is "the chain that holds the boat" rather than the anchor. I think you did some baseline tests to determine the holding capacity of the chain alone (with no anchor, or weight) I imagine this was very low, but if you could quantify this together with the chain specifications it might help dispel the myth that that it is chain rather than the anchor doing the work. This sometimes confuses anchor threads and it would be great to dispel this myth.

Thank you. We only used 20 ft (6m) of 3/8" G4 chain, along with wire rope, so I don't think I can help with that argument.

 

[OceanSprint]

Lunch, anyone?

 

[noelex]

I have just been through the photos to see if I could find any results in mud.

This sort of substrate should be ideal for "clogging" with a light covering of weed over firm mud. The weed tends to bind and clump the mud together which would make the clogging worse if it were to occur. You can see the Mantus (which is a concave roll bar anchor) has done a great job. It has set deeply. The fluke is completely buried and even the top of the shank is several inches below the surface.

Of course there are many types of mud and I will be able to get some more photos in the winter anchorages in different consistencies, but the sort of substrate shown here should be just the sort of substrate that would cause a problem if one was going to occur.

(The cloudy result is because the photo was taken only just after the anchor was set, not because it was dragging)
(Note: Mantus have supplied this anchor at no charge for me to test )

 

[J Neeves]

Noelex,

A very impressive performance and very convincing for anyone want to buy a 57kg anchor. It would be interesting to see how a 57kg, say Spade or Supreme performed in the same seabed set the same way, you could substitute a Rocna for the Supreme. it would be equally impressive to see how a 20kg - 30kg Mantus (a more common size perhaps) performed as well.

Many people would relate to the idea that larger (and in your case much larger) anchor can perform differently, commonly better, that their smaller brethren. Consequently the performance of a 57kg model might bear little comparison to a 20kg model.

It also merits mention that you are setting this 57kg anchor with a 10mm chain, (whereas I suspect most would using at least 12mm with this size of anchor) and that smaller chain has a much lower resistance to retarding the setting of an anchor.

Jonathan

 

[vyv_cox]

Noelex

When you read the last three pages of “Real world Experiences “ pages 9 to 11-- you will hopefully get the gist of what some, including myself have been saying, your photos are great, your experience is unquestionable, unfortunately your knowledge in anchor technology as to how they work, I have said this before- is far from mark, this is the problem when you try and make unrealistic comparisons by guessing, observations with an anchor sizing that is huge in comparison of the various designs of possible lighter designs.

Your input has been very good as your assumptions have been put to the test, quantified by real world experience, a good anchor as you put will not heap up the substrate, not true, listing is another down side so you say, not true, listing is encouraged in many designs for reasons explained in post 81 –padge 9

None of what you say other than new generation anchors are an improvement can be quantified by your photo’s unless it is all an apples to apples comparisons, you say look at my photos, then you be the judge, well fair enough but when I made comment as to how I saw the performance of the Ultra being due to a weed ball, you then came back and did not stand by your quote: you be the judge statement, you further went on to persuade- disagree with me.

Noelex I have spent many, many hours in anchor technology involved with the Monash University students, ANCHORS ARE NOT JUST ANCHORS, you cannot just make assumptions based on what you see.

The following posted by LadyInbed,

I am one who only uses moderate revs to straighten out the 8mm chain (always 5xD and 20m minimum) and set my over size Delta.
I hold it on those revs whilst watching that a transit doesn't change, then shut the engine down, put an anchor wp on the plotter, have dinner and a good nights sleep.
Should I worry more?
End Quote:

Noelex,

just what if some of those Deltas you photographed had of been the same weight as your huge Mantus, just maybe you would have experienced-- been able to shoot some great shots of a Delta really getting down and dirty instead calling poor sets typical of Deltas.

Anyway once again Noelex thank you for your great experiment on how not to judge anchor performance, possibly why you could not answer some of my more technical questions, it has been an Eye opener, Oh one other thing, the link to the anchors, http://www.sailnet.com/forums/seaman...ng-woes-4.html Rocna , Mantus, Manson excetra, thanks for that, what does stand out is the Mantus has a longer shank, it is also quite a lot thinner than all of the new gen, further observation is that the fluke seems to have a larger holding area, this doesn’t compute, why the shank so long, thin, more load, more leverage, rather odd-- no wonder the shank on your Mantus yielded in light conditions.

It would want to match at least the Rocna profile strength at least if I wanted one.
Any way as an example you could take a page out of MAIN SALES anchor testing methods, very interesting and closer to the mark.
Regards John.

This is a very aggressive post for no reason that I can understand. Long on criticism, short on facts. Most of us would assume that an anchor is set at its best when it is flat with a symmetrical appearance. You seem to be saying otherwise. Can you please supply some information, links, photos of your own?

 

[basic]

Yes, I was going to chip in with a similar point.

I use exactly the same technique with my 10kg Bruce. Encouraged by reports that the anchor was designed to do well on a short scope I have had good results with scope as little as 1.5 the depth of water. Very handy when you have to lug it up manually. In fact, when staying overnight, I always set the Bruce on a short scope, let it lie and then veer the rest of the chain.
On a making tide I once watched the thing hold to the very last before letting go, the chain was silent as all of it was off the seabed.

A+...Long live the genuine Bruce.

 

[vyv_cox]

Noelex,

A very impressive performance and very convincing for anyone want to buy a 57kg anchor. It would be interesting to see how a 57kg, say Spade or Supreme performed in the same seabed set the same way, you could substitute a Rocna for the Supreme. it would be equally impressive to see how a 20kg - 30kg Mantus (a more common size perhaps) performed as well.

Many people would relate to the idea that larger (and in your case much larger) anchor can perform differently, commonly better, that their smaller brethren. Consequently the performance of a 57kg model might bear little comparison to a 20kg model.

It also merits mention that you are setting this 57kg anchor with a 10mm chain, (whereas I suspect most would using at least 12mm with this size of anchor) and that smaller chain has a much lower resistance to retarding the setting of an anchor.

Jonathan

Not the same bottom of course, nice sand. 15 kg Rocna, 8 mm chain, no swivel(!). We are berthed stern-to here, so the pull is greater than it would normally be other than in strong winds.

 

[J Neeves]

Vyv,

Nice paint job, better than the alternative of greek blue.

Jonathan

 

[Bloomy]

VY Wrote:

This is a very aggressive post for no reason that I can understand. Long on criticism, short on facts. Most of us would assume that an anchor is set at its best when it is flat with a symmetrical appearance. You seem to be saying otherwise. Can you please supply some information, links, photos of your own?

John Responded:

Yes well I can be a bit critical I suppose, especially when a man like Noelexs experience should know better than to make observations and compare performance of possibly smaller anchors than his huge anchor, it is misleading when anchor testing if its not apples with apples, critical you say, well he wasn’t exactly to complimentary with the John knox test, went on to say he is syndical- skeptical of anchor designers testing in general, I can’t think of anyone more respectful than John Knox .

Symmetrical anchor setting is certainly the characteristics of most anchor designs when set, this is the thing, listing is mainly observed when setting any anchor design, difference being it is not a fault or down side, take the Spade for instance it has a lardge bullbas on the underside, concave shape, when setting or change of tide it pivots around on this listing, roll bar anchors may list less, it doesn’t mean it makes it a better design, Noelex is the one making the statements like typical of ------ let him do the yards and prove what he says.

Heaping is not the sign of a good anchor he says, well based on your experience and many others heaping is normal even with the concave, according to Noelex rarely is heaping the case with concave, (Rubbish) , any anchor design that doesn’t set strait away will heap the substrate, not setting strait away could be for many reasons and no fault of the anchor, “with these comments typical of Noelex” I don’t believe he knows much at all as to how anchors actually do work, further I think because of the time laps with Noelexs free anchor trials, Photos, criticisms amongst others he has developed a conflict of interest without realizing.
Anyway if I have offended anyone I am truly sorry, but I make no apology for the way I see it, most definitely it is not a personal attack, I am involved with many anchor makers, when I see these types of comparisons backed up with respect and great photos unless they are correct and fair I will complain as equally they can promote or desecrate a design.
Kind Regards John.

 

[Storyline]

I am not sure why you want me talk about mud. It is the one substrate that I have not encountered since getting the camera.
.....
.....

Anyone who takes an interest in the subject of anchoring and also gets satisfaction when laying their anchor and knowing that it is properly set is interested more than anything on how their anchor performs in different places. Can only speak for the Rocna but in sand/coarse shell/grit the anchor will set immediately and the technique for laying it seems not to make any difference. The photos of poorly set (roll bar) anchors you show in sand are (imo) just the result of someone not taking the trouble to dig it in and there has not been enough wind to do the job for them.

Mud however is very different - before Jonathan told me about the Fortress tests I thought I was alone in thinking that our Rocna was a poor performer in certain muddy places. As said above I have discovered a technique for getting it to set but I would be very interested in seeing pictures of roll bar anchors (and others) in mud. This may give me a clue about what is going on under the water other than the anchor just ploughing a furrow.

The issue is so serious for us that now we treat certain places as not being bomb proof even though they offer excellent shelter. Next year we can fix this problem by getting a Fortress which I think is now the number one priority to ensure Storyline remains seaworthy on the Scottish west coast now that unseasonable summer gales/storms are becoming more frequent. This is a trend that is likely to continue and get worse.

 

[noelex]

Noelex,

Many people would relate to the idea that larger (and in your case much larger) anchor can perform differently, commonly better, that their smaller brethren.

Wow

Jonathan you have championed the use of multiple small anchors for so long I never thought I would read something like that from you. You have long argued vigorously against the "Big is better" approach.

You have mentioned before how you feel a big anchor would not set well because the yacht could not provide enough force.

It is nice to read that you now feel a big anchor should actually do better than a smaller anchor of the same design. I am interpreting your views correctly, or are you perhaps saying this is what people believe, but it is not true?

Rather than using multiple 15kg anchors on 38 foot catamaran, perhaps you have seen the light and the advantages of the simple KISS system of a larger anchor.

I live in hope anyway .


I will post my thoughts on the scale effects shortly.

 

[Storyline]

@ Noelex. Surely no one would question that size (weight & surface area) is important and a larger anchor will outperform a smaller one of the same type. However this is not the end of the story. The main issue for me is that all members of the crew can actually handle and deploy the anchor and I would consider an anchor the same size as your Mantus actually dangerous on Storyline. Sure, we could rig up a way of handling it using a spare halyard etc but an anchor should be easy and safe to deploy in a hurry if needed. Therefore finding the right balance between size/performance/practicality of use is absolutely crucial imo.