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Old 13-11-2013, 02:59   #841
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Re: Anchors, Bigger is Better?

Noelex,

Its an anchor thread!

I beg to to differ

In soft mud one should let the anchor settle, gently, jiggle it a bit to let it settle. Once it has reached a firmer substrate below, then gently increase reverse - if the anchor is not gripping, jiggle a bit more - but on no account 'hard reverse' - the anchor will simply swim - unless of course its upside down. How do I know, I've tried, Rocna, Spade (steel and alloy), Fortress, Excel, SARCA, Kobra, Supreme, Ultra (not Mantus), Claw and Ray.

This idea that the Fortress with the help of the chain pulls the shank down is another of those phurphys - the mud flukes are specifically there to ensure the fluke tips are forced down, they will engage, the anchor will set - but treat it (and other anchors) as Moderators wish we treat fellow poster - gently, kindly, with accommodation - no harsh reverses in soft mud, please!

Every river anchorage on the east Coast of Australia is soft mud, we think we know.

Jonathan
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Old 13-11-2013, 03:01   #842
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Re: Anchors, Bigger is Better?

Quote:
Originally Posted by JonJo View Post
Noelex,

In nearly every test conducted internationally since 2006 the Spade has consistently performed as one of the top anchors having an ability to set quickly and develop exceptional holding capacity. These tests have been conducted in a variety of seabeds

But you say it does not dive

Possibly you can account for its consistent positive performance in tests (if it does not dive) in such a cross section of seabeds.
Calm down Jonathan. We are in complete agreement
The steel Spade is a great anchor. It sets (or dives) beautifully.

However if you could keep the same overall design and tip weight without the bulk of the Spades toe it would perform better. Other than sticking in some depleated uranium instead of lead such changes are not possible.

So with current design and technology we are left with a choice of a thicker toe, or a roll bar. Both are necessary evils to get the anchors respective designs to self right. To criticise one without acknowledging the drawbacks of the other is wrong.

Roll bar and thick toe they both inhibit the diving of the anchor to some degree.

Hopefully in the future we will have more designs that combine the best of both worlds no roll bar and no thick toe.
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Old 13-11-2013, 03:11   #843
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Re: Anchors, Bigger is Better?

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Originally Posted by JonJo View Post
Noelex,

Its an anchor thread!

I beg to to differ

In soft mud one should let the anchor settle, gently, jiggle it a bit to let it settle. Once it has reached a firmer substrate below, then gently increase reverse - if the anchor is not gripping, jiggle a bit more - but on no account 'hard reverse' - the anchor will simply swim - unless of course its upside down. How do I know, I've tried, Rocna, Spade (steel and alloy), Fortress, Excel, SARCA, Kobra, Supreme, Ultra (not Mantus), Claw and Ray.

This idea that the Fortress with the help of the chain pulls the shank down is another of those phurphys - the mud flukes are specifically there to ensure the fluke tips are forced down, they will engage, the anchor will set - but treat it (and other anchors) as Moderators wish we treat fellow poster - gently, kindly, with accommodation - no harsh reverses in soft mud, please!

Every river anchorage on the east Coast of Australia is soft mud, we think we know.

Jonathan
I think your setting technique and mine in soft mud are very much the same, with the exception that I end at least eventually in full reverse.
If the anchor will not hold in full reverse I will not stay overnight and I have never had to compromise this position so far.

The mud palms on the Fortress help ( in fact most use them all the time there is not much point in removing them) but Fortress still recommend the "short scope" technique for the initial set in very soft mud and I think it is good advice.
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Old 13-11-2013, 03:11   #844
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Re: Anchors, Bigger is Better?

[QUOTE=noelex 77;1389500]

Many (wrongly in my view) believe two identical anchors give them 2x the holding power of a single anchor. I think the gains are much more modest. unquote


I think that is what I said?


quote

Is it worth mucking about setting two anchors (for increased holding) when a 5 kg, or 10kg (10 -20lb) increase in your main anchor from say a 20 kg to 25-30 kg would achieve the same effect? Especially when this only represents a 4-8% increase in weight of your main anchoring gear (assuming 50m (150feet) of chain).

unquote

Send me an airticket and I'll convince you that 2 x 20kg anchors (of different design) are better than one 25kg anchor. Even better I'll convince you that one 20kg anchor and a 10kg alloy are better then one 25kg anchor.


The crux of 'bigger is better' was the thesis of going 2 sizes bigger - not 5kg (or even 10kg) - it was about going 50% bigger. No-one would argue about going 5kg bigger - but frankly I doubt you would tell the difference.


quote

I agree all boats need to consider that they may need to cut away and lose their anchor, or anchors.
If you regularly use two anchors in bad conditions that means you need to carry 4 anchors and appropriate rode. This means carrying a great deal of heavy chain, if you are venturing into areas where rope is unsuitable, such as coral waters.

unquote

I fail to follow the logic, why carry 4 anchors and even if you do - surely you have heard of alloy? And what is all this about heavy chain, surely G7 chain if 'sized' for strength is hardly heavy.

Noelex - you sound as if you are weakening, you seem to be suggesting that bigger is better represents a 5kg increase in anchor weight and if you are happy with G7 chain then there is little weight penalty. I only need to convince you of alloy and you will be on side - sadly its an anchor thread and I might be too optimistic

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Old 13-11-2013, 03:23   #845
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Re: Anchors, Bigger is Better?

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Originally Posted by conachair View Post
How do you know? How does it end up upside down?

unquote

Its a yacht, if something can go wrong, it will.

I've tried it, all anchors can end up on their back (that's why the roll bars anchors have roll bars). The assumption is they will end up on their back and the roll bar facilitates their righting themselves. If they always ended up 'right way up' there would be no need for a roll bar and the market would be bigger - as many bow rollers will not take a roll bar. So I assure you the roll bar is there for a very good reason - to right the 'wrong' and the 'wrong' when it happens in soft mud is an issue.


quote:

I know my rocna works fine in soft mud but have never watched it to see how.
unquote

And I have tested Spades, alloy and steel, and never had an issue, they set quickly and dive. Equally the Kobra is a brilliantly simply design, sets quickly and has high holding - spoilt by a weak shank. If there were not alternatives the solution is simply, replace the shank

Jonathan
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Old 13-11-2013, 04:32   #846
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Re: Anchors, Bigger is Better?

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The deeper the anchor goes in a blow, the greater the weight of soil holding it in place.
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Originally Posted by Delfin View Post
Another opinion is that the largest anchor you can handle is going to be superior to a lighter anchor because of simple physics and the effect of gravity.
A small point but I disagree, the weight of sand or mud on top of the anchor has little effect given a good scope, particularly if we agree that the Spade doesn't bury itself deeply. It is the density of the seabed material in front of the anchor and its resistance to move out of the way that stops the anchor being pulled through the material.

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A heavier anchor has more surface area to bury, but more weight to help bury it. Alloy anchors like the Fortress seem to be the exception that proves the rule, but you have to be able to stow and handle a Fortress, and not all boats can.
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Summary - bigger is better because gravity is a real phenomenon, although I am willing to be convinced that an alloy Excel performs as well as a steel one. I doubt it, but I am open to the concept .
Sorry but you can't say both, either the weight (gravity) is important or the surface area. If weight (gravity) was important then a Fortress wouldn't work. Since it does, surface area is the key and whilst the larger anchor will hopefully have a greater surface area its weight is a secondary consideration.

Perhaps anchors should be painted with rough deck paint to increase the resistance to ploughing through a substrate. This would be the opposite to clearing snow with a wooden spades which traditionally were coated in candle wax so the snow didn't stick.

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Old 13-11-2013, 04:38   #847
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Re: Anchors, Bigger is Better?

Quote:
Originally Posted by JonJo View Post
So I assure you the roll bar is there for a very good reason - to right the 'wrong' and the 'wrong' when it happens in soft mud is an issue.
So what actually happens when a roll bar anchor lands upside down and sinks in soft mud?
I've had reduced holding in soft mud but never any problems getting g it set. Maybe having sunk into the mud the upwards pull on the shank pulls it round but again, I've never watched it so don't know. Do you have any video of a roll bar in soft mud to show how they really behave? Maybe I'm just lucky.
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Old 13-11-2013, 05:29   #848
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Red face Re: Anchors, Bigger is Better?

conachair

I don’t think the upside down issue is a huge problem, obviously it is not, but we had an anchor test against others many years back in France and were actually leading the competition, in this test Rocna performed very average, XYZ anchor won the day, it was a soft mud test, in the last pull they had to have two attempts to get the Sarca to set as it landed on the roll bar.

The roll bar sunk into the mud and as they were pulling it very slow it simply did not right itself, cost us a victory, if you are in strong wind the problem may right itself, but another issue we found when the anchor did land upside down it can collect a lot of weed in centre low of the roll bar, if combined with mud can exacerbate the problem to the point it just keeps slowly dragging upside down.

It’s a bit like having your anchor pick up a beach towel and you drag, upon retrieving the anchor the beach towel falls of and you are none the wiser for reason of dragging.

As mentioned in my previous post the secondary fluke solved this problem for us, it is more likely to happen I believe if you get a wind shift of 180 degrees, anchor is ripped out and lands on its back full of mud-weed whatever then the shank in very soft mud can sink, resulting in the roll bar being buried upside down, again there is no evidence that it won’t eventually right itself, the mere fact it can happen sparks debate. Any way our secondary fluke did solve this problem, but there was no real evidence that it caused a problem other than in the French test.

This is a very hard one to detect unless you are heavily into anchor development doing a lot observant testing.
I think being cautious when setting an anchor and not taking for granted from past performance you won’t drag, staying alert is sometimes your best defense regardless of anchor design.

Regards Rex.
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Old 13-11-2013, 05:39   #849
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Re: Anchors, Bigger is Better?

I find some of the claims and "facts" being tossed around by some here to be marketing crap used to make something sound important! Small items used to call other designs crap, but doing it with a suggested "just it just make sense" method.

Normally makes one more concerned about their anchor that reading an anchor thread.
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Old 13-11-2013, 05:56   #850
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Re: Anchors, Bigger is Better?

sailorboy1

Well sailor boy I suppose if you are an anchor manufacturer trying to share your experiences one could be forgiven for your observation - opinion, never mind it was genuine information not crap observed from over many years.
Sorry you see it that way, we don’t have a supplier over your way that is why I don’t bother advertising but pay the price for not.
But never mind if I think I can shine some light on a question then your comments will not deter me.
Regards Rex.
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Old 13-11-2013, 06:29   #851
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Re: Anchors, Bigger is Better?

I haven't read all of this but I see that the last few are on setting technique. So this is how I do it.
First I designed my anchor system to work in an emergency where there is no time for much thinking and I just want to get the boat anchored as fast as possible.

So I usually do the following with my bugel anchor.

If its blowing 25kts+, I decide where I am going to drop it and then I release the clutch and dump it all at an alarming rate until the chain mark comes up that I want 40,60 or 80 meters.
Then I put on the mini snubber to take the weight off the windlass and give it a pull steadily increasing to 1600revs.

If no wind or tide, I dump about 30 meters, then slightly tighten the clutch and then motor astern until the chain mark comes up.
Put on the mini snubber and then do the revs bit.
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Old 13-11-2013, 07:33   #852
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Re: Anchors, Bigger is Better?

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sailorboy1

Well sailor boy I suppose if you are an anchor manufacturer trying to share your experiences one could be forgiven for your observation - opinion, never mind it was genuine information not crap observed from over many years.
Sorry you see it that way, we don’t have a supplier over your way that is why I don’t bother advertising but pay the price for not.
But never mind if I think I can shine some light on a question then your comments will not deter me.
Regards Rex.

How did you know I was talking about you? Having been around mechanical equipment sales for years I am used to product "features" that sound nice but mean little in real life.

That's OK. Based on this and your various other low key trashing of other anchors I wouldn't buy your anchor anyway. Just like Craig Smith when on CF turned me off to the ronca. I can tell that you have lots of experience, but when someone tries so hard it starts to put up warning flags to me.
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Old 13-11-2013, 08:51   #853
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Re: Anchors, Bigger is better?

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A hollow, sealed, steel shank will contain air. When the sealed shank is dropped into the galvansing bath at about 570 degrees C the air is heated and expands, (this is all the fault of Robert Boyle I believe) I guess it depends on the amount of air and the thickness of the shank but considering an Ultra type shank - the resultant air pressure will blow the shank apart, there will be zinc everywhere. Galvanisers will not galvanise sealed bodies of this type. Spade's being open do not suffer with this issue - a steel Ultra would.

Seems intuitive to me.

You could make the shank open, as per Spade, but I am guessing that the buoyancy of the shank is part of the balance - but this is a guess.

Jonathan
Actually, Jonathon, if you apply the combined gas law you will find that with a fixed volume, the pressure increases as the ratio of temperatures expressed in Kelvin. In this case that is roughly 843:295 which is about 2.9:1. So, when the putative hollow, sealed shank is dipped into the galvo bath, the pressure goes from around 15 psi to around 42 psi... hardly enough to blow up a steel anchor shank.

I see no reason that one can't galvanize a hollow steel shank, sealed or not.

Cheers,

Jim
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Old 13-11-2013, 09:08   #854
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Re: Anchors, Bigger is Better?

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Originally Posted by noelex 77 View Post
The thick balasted toe of the Spade and Ultra (necessary because they have no roll bar) inhibits diving and unfortunatly this impediment is present as soon as the anchor starts to set.
Were that true, then one would think the thick ballasted toe would prevent the Ultra or Spade from setting as quickly as the unballasted toe of a roll bar anchor. But that's not what the tests show. The Spade and Ultra consistently set very quickly, as the PS test below shows. This test also shows the Kobra convex performing as well as the Manson, so I'm not sure what basis you have for believing that the French results were the only ones showing this level of performance from the Kobra.

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You must be reading different anchor tests.
I think the anchor test have shown overwhelmingly the superiority of the concave anchors and the (flat) aluminium Fortress.
I cannot think of single anchor test where the convex anchors have done anywhere near as well as the concave.
It dangerous to read too much into just one test. The test you quote is the only one I can remember where a convex anchor anchor featured in the top three. Nevertheless even in this test the only two concave anchors included in the group were rated number one and three. (Rocna was not included in the test anchors.)
You need to do more research. In this test, a convex anchor showed similar performance to the convex designs, with the ballasted toe Spade outperforming the roll bar anchors. http://www.newmorning.info/page65/fi...hor%20test.pdf

In this test, the convex anchors reset more quickly than their roll bar counterparts: Testing the new generation of anchors

I would also refer you to Rex Francis' (Anchorite) testing that is independently supervised. He is one of the few manufacturers who actually puts his product to the test compared to the competition in 'apples to apples' testing, and his testing methodology with the balance beam seems about as objective as any I have seen. Some may decide to reject his results on the basis that he is a manufacturer, but frankly, that is unconvincing, especially when it is so obviously a standard only selectively applied by those promoting the idea that you shouldn't listen to someone whose entire life is building and testing anchors, as has been demonstrated on this thread and other closed threads.

There is ample evidence that a ballasted toe presents no impediment to burying, while there is equivalent evidence that a hoop does. And to the extent that convex designs are tested, the 3rd generation models are virtually always top performers.
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Old 13-11-2013, 09:14   #855
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Re: Anchors, Bigger is better?

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Actually, Jonathon, if you apply the combined gas law you will find that with a fixed volume, the pressure increases as the ratio of temperatures expressed in Kelvin. In this case that is roughly 843:295 which is about 2.9:1. So, when the putative hollow, sealed shank is dipped into the galvo bath, the pressure goes from around 15 psi to around 42 psi... hardly enough to blow up a steel anchor shank.

I see no reason that one can't galvanize a hollow steel shank, sealed or not.

Cheers,

Jim
Jim, why does Spade pour the lead in after galvanizing? Why not just pour the lead in, box it off like the stainless Ultra and then galvanize? Bit confused on that, since one of the complaints leveled against the Spade is that you can't re-galvanize easily because the lead melts and has to be recovered and re-poured, or so I think I've been told.
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