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Old 03-07-2013, 01:43   #61
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Re: Rocna repositioned

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Originally Posted by congo View Post
When you go back to our original Sarca twenty years prior now to Super Sarca it was of concave design with a thick hoop, recognizing the problem and then researching we simply turned the fluke plate upside down to from a concave fluke to convex,]
Rex you must know your anchor models having designed them, but I am puzzled by your comments.

I remember the Sarca anchor and it appears to me the major change from the older Sarca model to the newer Super Sarca model was to change the rear of the the anchor from turning down (convex) to the rear of the anchor turning up (concave) in newer Super Sarca. ( the rest of blade is slightly convex in both models although the newer model appears less so).

I assume this was in response to anchor tests at the time which showed the superiority of the MS and Rocna (and the very different Spade and Fortress) presumably because of the concave blade.

Perhaps I am remembering wrong? It has been a long time since I have seen a Sarca anchor rather than newer Super Sarca

I did find the photos which seem to confirm my memory (first is the original Sarca second is a stainless steel Super Sarca.)

It seems strange that you champion the benefits of a convex design, but the evolution of the Sarca anchor seems, to becoming less convex. It is particularly puzzling that you seem to be implying the evolution from Sarca to Super Sarca was the opposite.
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Old 03-07-2013, 02:03   #62
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Re: Rocna repositioned

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Rex you must know your anchor models having designed them, but I am puzzled by your comments.

I remember the Sarca anchor and it appears to me the major change from the older Sarca model to the newer Super Sarca model was to change the rear of the the anchor from turning down (convex) to the rear of the anchor turning up (concave) in newer Super Sarca. ( the rest of blade is slightly convex in both models although the newer model appears less so).

I assume this was in response to anchor tests at the time which showed the superiority of the MS and Rocna (and the very different Spade and Fortress) presumably because of the concave blade.

Perhaps I am remembering wrong? It has been a long time since I have seen a Sarca anchor rather than newer Super Sarca

I did find the photos which seem to confirm my memory (first is the original Sarca second is a stainless steel Super Sarca.)

It seems strange that you champion the benefits of a convex design, but the evolution of the Sarca anchor seems, to becoming less convex. It is particularly puzzling that you seem to be implying the evolution from Sarca to Super Sarca was the opposite.

If you look at the video that Rex posted you will see that the first Sarca was a concave design, its at the beginning of the video.

Our own development and testing has proven the vast superiority of the convex blade in penetrating and holding below the surface.

Rex knows his stuff and his evolution from the first model to what he now makes has to be applauded.
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Old 03-07-2013, 04:58   #63
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Re: Rocna repositioned

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Originally Posted by noelex 77
Rex you must know your anchor models having designed them, but I am puzzled by your comments.

I remember the Sarca anchor and it appears to me the major change from the older Sarca model to the newer Super Sarca model was to change the rear of the the anchor from turning down (convex) to the rear of the anchor turning up (concave) in newer Super Sarca. ( the rest of blade is slightly convex in both models although the newer model appears less so).

I assume this was in response to anchor tests at the time which showed the superiority of the MS and Rocna (and the very different Spade and Fortress) presumably because of the concave blade.

Perhaps I am remembering wrong? It has been a long time since I have seen a Sarca anchor rather than newer Super Sarca

I did find the photos which seem to confirm my memory (first is the original Sarca second is a stainless steel Super Sarca.)

It seems strange that you champion the benefits of a convex design, but the evolution of the Sarca anchor seems, to becoming less convex. It is particularly puzzling that you seem to be implying the evolution from Sarca to Super Sarca was the opposite



Nolex you are a whirly caricature, your observation is spot on, so spot on infact I have to wonder if you have other interest at heart, for some one that has demonstrated much resistance to the concept of our product why would you bother to going into so much detail, you must be checking and observing every move we make, Why?

Yes the convex does vary regardless they are still convex, here’s one for you, different sizes requires convex variations as their applications vary, this is for you to ponder as no one else would have picked this up, sorry but I will not be enlightening you as to why.

Moving away from convex to less convex, really, you must be looking at the Excel upside down.
It is sad that since the launch of your anchor design respect for all anchor manufacturers deigns are tarred with the one brush and treated with contempt.

Grant, thanks for your kind words, not often you see a opposition company support another.
Further , Delfin of whom I have great respect for made a valid point, I just wanted to clarify the variations of roll bar style anchors and how they work not start another long debate.

Burls, it was a pity you didn’t come to the Adelaide boat show as we had a stand their, what was interesting was a gentleman that had purchased a no 6 -- 30 KG Excel from the previous show stated to me since his purchase he has never dragged, even in that grass, he went on to say there was plenty of evidence upon retrieving the Excel but never dragged regardless, I may be able to find his number and you could ring him yourself, who knows you may well know him.

Regards Rex.
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Old 03-07-2013, 07:06   #64
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Re: Rocna repositioned

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Originally Posted by congo View Post
Quote:



Nolex you are a whirly caricature, your observation is spot on, so spot on infact I have to wonder if you have other interest at heart, for some one that has demonstrated much resistance to the concept of our product why would you bother to going into so much detail, you must be checking and observing every move we make, Why?

Yes the convex does vary regardless they are still convex, here’s one for you, different sizes requires convex variations as their applications vary, this is for you to ponder as no one else would have picked this up, sorry but I will not be enlightening you as to why.

Moving away from convex to less convex, really, you must be looking at the Excel upside down.
It is sad that since the launch of your anchor design respect for all anchor manufacturers deigns are tarred with the one brush and treated with contempt.

Grant, thanks for your kind words, not often you see a opposition company support another.
Further , Delfin of whom I have great respect for made a valid point, I just wanted to clarify the variations of roll bar style anchors and how they work not start another long debate.

Burls, it was a pity you didn’t come to the Adelaide boat show as we had a stand their, what was interesting was a gentleman that had purchased a no 6 -- 30 KG Excel from the previous show stated to me since his purchase he has never dragged, even in that grass, he went on to say there was plenty of evidence upon retrieving the Excel but never dragged regardless, I may be able to find his number and you could ring him yourself, who knows you may well know him.

Regards Rex.
Rex, thank you for pointing that out. My comments on roll bars did refer to concave designs that funnel what is dug up inwards, compressing it and depending on the sea bed, building up in front of the bar. The Super Sarca is convex, which would move the soil away to the outside, and I guess by making the bar itself thinner, resistance to burying would also be reduced. I can see the difference.

Incidentally, I walked by a boat yesterday on my dock and noticed what must have been a new Rocna 25. At least it still had the bar code from the store on it, and sure enough, the shank was bent! It didn't look like it could have been used more than once or twice and while the bend was only about 3/8", it was definitely askew. I'll try to get a picture today and post it. Does Q620 bent that easily?
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Old 03-07-2013, 07:46   #65
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Re: Rocna Repositioned

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Originally Posted by congo View Post
Nolex you are a whirly caricature, your observation is spot on, so spot on infact I have to wonder if you have other interest at heart, for some one that has demonstrated much resistance to the concept of our product why would you bother to going into so much detail, you must be checking and observing every move we make, Why?

Whirly ? You have obviously seen my sailing hat

Just for the record:
I don't have, nor have I ever had, any connection or association with any of the anchor manufacturers.

Now back to anchors
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Old 03-07-2013, 15:52   #66
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Re: Rocna Repositioned

Not very erudite but here's my quick take on how they work.

SARCA, convex anchor that shovels some of the seabed away from the fluke. When buried this process continues but as the anchor dives some seabed does flow through the gap between hoop and fluke. But the fluke bends down at the rear, a lower trailing edge, and the volume of seabed flowing through is less than the allowable volume, some has been thrown aside and the drop in the rear of the fluke would allow more through - the end result is no compaction. But the seabed thrown aside compacts and eventually stops further forward movement, the anchor is set.

A roll barred concave anchor 'channels' all the seabed into the fluke, the fluke becomes restricted at the rear, it has a lifted aft section to the fluke, a lifted trailing edge. There is also a roll bar - the volume of seabed passing through this space is constrained and can block. In fact if you take the roll bar away the seabed can flow though unrestricted and the anchor will never hold. The roll bar is there to stop this. It actually needs to compact and restrain the seabed or it will never hold.

Someone will say the roll bar is there to allow the anchor to turn over, actually the anchors, or some of them self right without the roll bar (which is why they have the Gordon Lyall shank) - but the roll bar is needed to make the anchor 'hold'. I have seen roll barred anchors with the roll bar cut off, which is fine for lunchtime stops.

The roll bar also reduces the depth of diving as it is a restriction and negates some of the fluke surface area. The roll bar actually has a surprisingly large surface area. The surface area figures that some, most, quote are misleading

The Boss is a variation, it has a huge fluke and a very thin shank - this allows it to dive further. It 'seems' to work simply because it is able to dive much more deeply - but its an anchor I have never tried so cannot comment - I'm simply guessing.

The Fortress cuts the seabed like a knife but it has two plates (mud palms?) at the rear that compress the seabed and a stock that contributes to resist diving. When the 2 rear plates plus stock balance the pull on the chain the anchor will then hold - but because these 'resistors' are quite small - the anchor can set exceptionally well (more than an other) and can be difficult to retrieve (set a trip line in strong winds).

Convex anchors push the seabed aside and compress it, when they cannot compress further, which will occur as they dive more deeply, they will then hold. This mechanism works also for the Spade as it also compresses seabed from the underside, which stops forward movement and it then relies on surface area of the top of the fluke plate to resist lifting.

Comments?

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Old 03-07-2013, 16:17   #67
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Re: Rocna Repositioned

Jonathan,

Comments?

Insightfull and poetic to the yachtsman's ears.
Thank you.

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Old 03-07-2013, 16:31   #68
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Re: Rocna Repositioned

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Not very erudite but here's my quick take on how they work.

SARCA, convex anchor that shovels some of the seabed away from the fluke. When buried this process continues but as the anchor dives some seabed does flow through the gap between hoop and fluke. But the fluke bends down at the rear, a lower trailing edge, and the volume of seabed flowing through is less than the allowable volume, some has been thrown aside and the drop in the rear of the fluke would allow more through - the end result is no compaction. But the seabed thrown aside compacts and eventually stops further forward movement, the anchor is set.

A roll barred concave anchor 'channels' all the seabed into the fluke, the fluke becomes restricted at the rear, it has a lifted aft section to the fluke, a lifted trailing edge. There is also a roll bar - the volume of seabed passing through this space is constrained and can block. In fact if you take the roll bar away the seabed can flow though unrestricted and the anchor will never hold. The roll bar is there to stop this. It actually needs to compact and restrain the seabed or it will never hold.

Someone will say the roll bar is there to allow the anchor to turn over, actually the anchors, or some of them self right without the roll bar (which is why they have the Gordon Lyall shank) - but the roll bar is needed to make the anchor 'hold'. I have seen roll barred anchors with the roll bar cut off, which is fine for lunchtime stops.

The roll bar also reduces the depth of diving as it is a restriction and negates some of the fluke surface area. The roll bar actually has a surprisingly large surface area. The surface area figures that some, most, quote are misleading

The Boss is a variation, it has a huge fluke and a very thin shank - this allows it to dive further. It 'seems' to work simply because it is able to dive much more deeply - but its an anchor I have never tried so cannot comment - I'm simply guessing.

The Fortress cuts the seabed like a knife but it has two plates (mud palms?) at the rear that compress the seabed and a stock that contributes to resist diving. When the 2 rear plates plus stock balance the pull on the chain the anchor will then hold - but because these 'resistors' are quite small - the anchor can set exceptionally well (more than an other) and can be difficult to retrieve (set a trip line in strong winds).

Convex anchors push the seabed aside and compress it, when they cannot compress further, which will occur as they dive more deeply, they will then hold. This mechanism works also for the Spade as it also compresses seabed from the underside, which stops forward movement and it then relies on surface area of the top of the fluke plate to resist lifting.

Comments?

Jonathan
You have pretty much summed it up there with your explanation Jonathan.

The points about the roll bar are spot on in that the roll bar acts like a brake for the blade to stop ploughing and hold. Without the roll bar on these designs they would just keep ploughing along due to the concave nature of the blade and nothing to stop it. The Roll bar also prevents the blade from rotating beneath the surface to a huge extent and so the sideways force is all taken by the shank, hence the bending results when the anchor is locked into the seabed. If it cant rotate it will bend. If it does rotate then the concave shape of the blade tends to break the anchor out allowing it to reset as fast as the anchor design will allow it to do so.

The convex shaped blades, without roll bars, will plough and dig deeper below the surface and also can rotate when sideways forces are applied usually without breaking out and having to reset, thus reducing the stresses on the shank. The only problem with the convex blades is how do you apply the brakes to stop it also just ploughing along. The answer is you either put a roll bar on it or you design brake foils into the blade to stop forward movement once the blade cuts below the surface. If you put a roll bar on it then it needs to be of a thin diameter or you come up against the same problem as the other concave roll bar anchors and it cannot rotate and take pressure off the shank.

The secret is to look beyond the publicity hype surrounding some designs and think logically about what makes the design work and what could cause problems below the water that you have no control over.
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Old 04-07-2013, 01:27   #69
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Re: Rocna Repositioned

I am glad we are back on track,I think these discussions on how anchors perform can be very illuminating, but I disagree with a couple of he contentions proposed.

1. The roll bar anchors dive less deeply.
I dive and see a lot of anchors in the real world and the roll bar anchors are always set very deep. They are invariably the best in any anchorage (apart from the spade which is equal)
Roll bar anchors have a much thinner toe profile than the non roll bar anchors. The thin toe penetrates much easier than the thick toe seen non roll bar anchors such as the Spade.
Both the thick toe profile of the non roll bar anchors and the roll bar itself on anchors so equipped must induce drag and inhibit the depth of dive.
At least the roll bar does not have any effect until the anchor is at least reasonably well set.

There are a few non roll bar anchors with a thin tip profile and a concave blade. I think up this is where the future lies, but so far most of the anchors like this such as Oceane, Sword, Raya etc have been dismal failures. The Manson Boss is the new player with these characteristics only time will tell if can avoid the pitfalls of other anchors in its class which is an inconsistency of performance. Exceptional good performance, but also some dismal failures.

2. The roll bar is needed for the anchor to hold.
Without the roll bar the anchor would have an inconsistent set, but once the anchor is set and buried I would contend you could cut the roll bar off with very little change in performance. (With the same direction of pull)

Once set,without the roll bar the anchor is just a concave profile, much like the spade, buried under the sea bed surface. Why would it not hold well?
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Old 04-07-2013, 03:20   #70
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Re: Rocna Repositioned

Sorry Noelex,

I did not define precisely the limits of my comments

I did say they were not erudite!

The discussion restarted from something someone said about the SARCA.

I omitted to mention that my comments were restricted to 'diving' anchors. By a diving anchor I refer to an anchor that, when loaded, generally disappears and pulls the chain down with it. My definition of a diving anchor excludes many 'common' anchors as many convex anchors simply do not commonly dive - so I exclude CQR and Deltas and, usually poor, copies of same. It is possible in exceptional circumstances to get a CQR or Delta to dive (and I'd then think they would exhibit to a greater or lesser (I'd think lesser) extend the qualities of convex I briefly described). But a diving CQR is so exceptional - I ignore it and I thus accept that a roll bar anchor will dive much more deeply.

My group of diving anchors is limited to those with which I have personal experience having actually used them and - in no particular order, Bruce (and good copies), Supreme, Rocna, Excel, SARCA, Fortress, Mantus, Kobra and Spade (I confess to only having used good copies but not an original Bruce).

I am not suggesting that all convex are as good as others nor that all concave perform as well - I was generalising mechanisms for diving concave, for diving convex and for (all by itself) the diving Fortress.

As I say a Delta, or Delta type might dive in some environments but I have tried it and do not find it so (and from comment - nor do others find it to dive).

I am also conscious I have not tried a whole host of anchors Wasi's Bugel, Raya etc. So I'm not being critical - I simply cannot comment.

It is quite possible to say that an Excel is a copy of a Delta (its been said many times). I'm not going to argue, it is impossible to argue with someone who has no idea never having seen one or used one. However an Excel does dive (every time) and I have never had a Delta dive - so I think they are different. I see the differences but I have no idea which is critical and which is not - I'm guessing that's the trick (making an anchor that works )

You mention that of the anchors you see the Rocna sets better than any other apart from the Spade (I'd agree that both set well) but also say the Spade (which you say sets equally) has a 'less thin' profile. This is something of a contradiction - if the Spade has a clumsy profile but sets as well as the thin and streamlined profile of the Rocna then Spade have something 'right' that is not explained by the usual argument of thick and thin profile?

But the debate I started, and asked for comments, was actually not about whose best (I actually wanted to avoid that ). It was meant to be about how the various designs worked, mechanisms rather than degrees of excellence (which only go round in circles). We can get into whose better, whose best, next year!

So apologies if anyone's choice of anchor suggests I'm snubbing them, that was not the intent - but easily done.

Can we look at mechanisms?

Comments?

Jonathan
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Old 04-07-2013, 04:18   #71
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Re: Rocna Repositioned

Interesting comments Johnathan.

I do not make the distinction between "diving" and "non diving" anchors. I just don't see the dichotomy. Rather I see a range of performance with some anchors burying deep than others.
Some anchors that set deeply in soft substrates do not set deeply in hard substrates, further blurring the distinction between the two groups.
The depth of this bury is a very important component of the holding power. The depth of bury combined with the blade area, blade profile, and angle of the blade determine the holding power.

However I do agree that that the Delta for example (which a think is still a reasonable anchor) has a weakness that in softer substrates offers less resistance than other anchor. On several occasions I have seen one completely below the surface (so none of the anchor is visible) nevertheless which each gust you can see the sand on top move like a burrowing animal traveling underground. The anchor is slowly dragging backwards. Rather than poor diving I think its biggest weakness is relatively low resistance when buried to same depth as other anchors. On the positive side it sets rapidly quickly and reliably.
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You mention that of the anchors you see the Rocna sets better than any other apart from the Spade (I'd agree that both set well) but also say the Spade (which you say sets equally) has a 'less thin' profile. This is something of a contradiction - if the Spade has a clumsy profile but sets as well as the thin and streamlined profile of the Rocna then Spade have something 'right' that is not explained by the usual argument of thick and thin profile?
Not just the Rocna, but the MS and Bugal they all set well and deeply.
The spade sets well,in part, because of heavily ballasted tip. Unfortunaly adding lead weight to the tip also adds bulk.

There is the possibility of fusing the advantages of the Spade and Rocna using geometry to create a high tip force like the Rocna without the bulky tip like the Spade. The expiration of the Spades patents (which is just about now) will enable some new possibilities and think we will see another leap forward in anchor design.
However, the very clever Spades designer Alain Poiraud (unfortunatly now deceased) could not produce a successful Spade like anchor without the ballasted tip even though he tried with a couple models.
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Old 04-07-2013, 05:07   #72
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Re: Rocna Repositioned

Mechanisms,

Let me add another dimension and if you will humour me - I'll limit my musings to those anchors I think are diving anchors (I'm happy to add a Bugel to the list).

In order to develop holding capacity the anchor needs to dive and the more it dives the better that holding capacity. You mention the Delta pulling though the seabed - this is not an anchor with an adequate holding capacity nor in my definition a diving anchor. Its simply surfing.

But an anchor will not dive for ever, it is constrained by the seabed The seabed usually becomes denser with depth, but it is also constrained by the chain. The deeper any anchor sets it must pull the chain down as well. The chain has surface area and the bigger the chain (for a given size anchor) the less well the anchor will set. This will occur in any seabed but more so in denser or harder seabeds. In fact in soft seabeds, mud, the seabed can squeeze through the holes in the links in a hard, weedy or coarse seabed the holes in the links will in effect be 'solid', or perform as solid

But the chain also offers a further constraint. As the chain is pulled down it adopts a reverse catenary, tending toward the vertical at the shackle point. I'm not saying it is vertical, but moves from the horizontal.

So 2 things happen, as the anchor dives and more and more chain is pulled into the seabed and the surface area of chain (in the seabed) increases. As the chain is pulled down and it becomes more vertical, where it meets the anchor, the angle of the load on the anchor increases from the horizontal - both of these effects will stabilise the anchor at a given depth based on size of chain, hardness of seabed, the load and size of anchor.

Consequently all anchors will 'stabilise' out.

If nothing restrains the anchor, its a simple plate (flat like a Fortress or curved like Supreme) then it could squirrel its way (with the plate or curved fluke parallel to the seabed) through the seabed. The roll bar and upturned trailing edge are essential to stop the squirreling by compaction at the roll bar or in the case of the Spade and convex anchors that forcing of the seabed aside increasing density or compaction (but to the sides, or underneath in the case of the Spade). In the case of the Fortress its compaction by or at the mud palms and stock (though these tend to be small) I appreciate the Bugel has no upturned trailing edge but it does have a fairly large roll bar surface area (and the fluke is not excessive in area - and in fact quite beefy, so some compaction round the leading edges). The bugel unusally has a thick shank - also retarding it diving, for ever!

Some evidence - when an anchor sets it tends to adopt an attitude where the fluke is at an angle of about 30 degrees to the seabed. A well set anchor, say 2' deep, (if you dig it out) has a fluke attitude roughly horizontal - so the fluke attitude moves through 30 degrees as it dives.

As Fortress owners can find - the small compaction ability (imposed by the mud palms) becomes a real issue after a hurricane when the anchor is buried so deep it can be difficult to retrieve - but normally this is not an issue and can be overcome with forethought, a tripping line.

again comments?
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Old 04-07-2013, 07:58   #73
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Re: Rocna Repositioned

Thoughtful analysis, Jonathan, thank you. Your remarks on the free burying of the Fortress I agree with, which is why it makes such a great standby storm anchor. Better buried deep than not in extreme conditions. I also agree on the basic distinction between diving and non diving. My own view is that the current crop of roll bar anchors will all set quickly but cannot provide the same ultimate holding when compared to a diving anchor because the roll bar will provide far more resistance to burying than a ballasted, but thicker tip.

Regarding quick setting, the Spade with a ballasted but thicker toe is known for setting instantly, so I'm not sure the argument can be made that a hoop anchor with a thinner toe offers any advantage there, but does offer disadvantages as owners of Rocnas have attested when the seabed is trapped by a hoop acting as a backboard.

And while I have limited experience with it, I have been using an Ultra for a few weeks, and when it hits the seabed it brings Delfin's 65 tons to a halt, and instantly. This anchor has most of its weight in the tip, which also curves down, like an Excel's. Because of this weight distribution and tip design, I expect to be able to confirm the manufacturer's claims over time. Well see, but the few independent tests that include the Ultra seem to confirm this.
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Old 04-07-2013, 08:05   #74
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Re: Rocna Repositioned

I agree with most of your assessment Jonathan, but some consideration should also be given to the resistance of the anchor design.

Substrates get denser as you go deeper, but for some the effect is is not particularly significant for the depths we are talking about. In others a layer of rock below the sand will prevent any anchor digging in further no matter how good the design.

On the other hand in soft mud bottoms deep penetration is essential.

Try pushing a stick in the seabed to get some idea of the change with depth.

The projected surface area of the fluke together with its resistance based on the shape and angle of attack therefore play a big role, and should be considered when the likely holding power is assessed.

If the fluke of a modern concave shaped anchors with a large blade area is completely buried in sand substrate you are unlikely to going anywhere in most winds.

Bury an one of the older smaller convex bladed anchors to the same degree and the holding is much less secure.
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Old 04-07-2013, 15:37   #75
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Re: Rocna Repositioned

My comments were simplistic, I was not going to get into too much detail, I'm not sure anyone has the answers, I'm not even sure we know what the questions are.

I recall anchoring in Bramble Cove, (SW Tasmania) lovely place. It has a gorgeous sand seabed, you can see it (through the Tannin). Sadly the sand is only about 100mm thick in many places, underneath are stones, they seem fairly regular about 25mm in size. One of those places where a big chain will be disadvantageous. It faces SW where the weather comes from so when it turns bad no-one uses it - so whether the holding is good I do not know - but I suspect it might be found wanting.

My pontifications tend to be on the basis of a regular seabed type with an even composition that will increase in density with depth. Certainly as the anchor dives the increased density of the seabed will decrease the ability of an anchor to dive (and this, with the increased resistance of the chain will contribute to how deep it goes before bottoming out). Any resistance to diving, thick shank, thick fluke etc will discourage deeper diving (which is why we have thin shanks compared to those beefy shanks of the original CQRs and Danforths).

What the chain does is lift the end of the shank (toward the top of the seabed) allowing the fluke to become horizontal. Without this upward force from the chain as it angles further from the horizontal the anchor would just go down and down as the load is increased (until load and seabed resistance are in balance.

But anyone with a Rocna or Supreme, it merits measuring the roll bar, they are surprisingly large in terms of surface area, detracting from the large surface area of the fluke )noting that the Rocna is specifically sold on surface area). Equally the surface area of a Fortress is massive, for the recommended sized yacht the Fortress tends to be 20%-30% larger than anything else.

I see implications to my ideas - which is why I'd love comments to then test (in my own mind) the validity of the implications.

Jonathan
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