Spade corrosion

Thank you for your further replies.
Not on the boat at the moment, so I am unsure what it looks like down the ballast chamber.
I do not remember seeing any white salts or powder, though if these were produced gradually, I suppose they might have been washed away.
This anchor is the one I have used most frequently over the years, so it is far from being an ornament. On the other hand, the season is short here and it spends some six months out of twelve in the shed.
Next step will be taking the anchor and bill of sale to the distributor. I will keep you updated on the outcome.
 
It appears that the confirmed and documented reports of corrosion between lead and aluminium in Spades aluminium anchors are, so far, the sum total of.......2. These two incidents occurred some considerable time ago and if there have been recent cases - they are undocumented to the wider public.

The issue may be well known (I wonder why), and from the images, simultaneously awful and stunning, but if the issue has occurred it has been of insufficient interest to be remembered by anyone (they have not bothered to post any evidence).

As a user of the same anchor I confess to being sensitive to the issue and do monitor, fruitlessly (so far).

I would like to see the ballast chamber sealed, as a precaution - but maybe Spade are sufficiently confident of their remedy to find this unnecessary.

In common with others who actually use aluminium anchors we find it and the other aluminium anchors, Excel and Fortress, more than adequate and have no hesitation in their use.

Considering previous and current issues with other anchors - in the absence of more evidence the fears of lead/aluminium corrosion in the current Spade model appear groundless. Those fears pale into insignificance against other documented anchor failure incidents and design failures.

The failure of the current anchor is a concern - it will be interesting to hear confirmation of the cause of the failure - and any remedial actions of benefit to the owner.

Jonathan
 
If you google 'aluminium Spade anchor corrosion' you will find more than two examples, one of which is considerably more dramatic than either of the two of which we have photographs. I understand that the one that preceded my photographed one was far more badly pitted but I never saw that one.

See www.trimaran-naga.com
 
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vyv_cox said:
If you google 'aluminium Spade anchor corrosion' you will find more than two examples, one of which is considerably more dramatic than either of the two of which we have photographs. I understand that the one that preceded my photographed one was far more badly pitted but I never saw that one.

See www.trimaran-naga.com
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It seems 2004 was a bad year for Spade - anything more recent? If not, as we moved on which bendy shanks.......

Jonathan
 
Neeves said:
It seems 2004 was a bad year for Spade - anything more recent? If not, as we moved on which bendy shanks.......

Jonathan
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I think the one on my website was photographed in 2013, when it was two years old. That one, being a replacement of a failed one from Spade, had the isolation modification. The owner in my link above seems to be satisfied that the modification has worked.

I also doubted that a barrier of epoxy could survive molten lead poured into it but the owner was sure that was the solution.
 
The exposed lead in the steel Spade is fine. The interaction between steel and lead is not going to cause any problems, but to use the same design for an aluminium anchor is rather surprising. The galvanic series has been known for a long time.

There does not have to any water between the lead and aluminium for corrosion to occur. If the lead and aluminium are in electrical contact and both are immersed in seawater you have just created a nice battery. The aluminium will corrode, just as this thread graphically illustrates.

The only hope is that the coating Spade has applied to the aluminium before the lead is added will stop (hopefully long term) the lead and aluminium from touching and forming any electrical contact.

A totally sealed (with a welded aluminium plate) ballast chamber could be added to the aluminium Spade as a future design change. The difficulty here is that the ballast chamber has to remain sealed at a considerable pressure. This is not easy to achieve. Aluminium water, fuel tanks as well as other sealed boat structures are tested to around 5 Psi after manufacture. It is not unusual for this test to show pinhole leak at this pressure, with repeat welding needed to achieve a seal.

For an anchor with an arbitrary (and unrealistic) depth limit of 20m, the weld has to be tight at 30psi and maintain this integrity for the expected life of the anchor. In the extreme case if the anchor is ever dropped accidentally in deep water at 100m the pressure is almost 150 psi. Together with the pressure caused by the depth, the sealed chamber has to survive the fluke hitting rocks and other wear and tear as a normal part of use. Anchors have a tough life :). The owner would not realise the ballast chamber was not air tight until corrosion started to occur. These design and construction challenges are not impossible to overcome, but the difficultes incorporating lead into the aluminium Spade are much greater than the steel version and a sealed lead chamber is not a great option in my view.

Fortress has already shown that an anchor design that does not need ballast is a much more successful candidate for conversion into an aluminium model. It would be nice to see a company produce one of the concave rollbar anchors in aluminium. Like the Danforth/Fortress design, the concave roll bar models require no, or at least minimal ballast. Where a small amount of ballast is added on the steel concave rollbar models it is just a small area of thickening of the fluke near the toe. The same could be done for an aluminium version. This avoids any disimilar metals and the associated aluminium corrosion.

Even better would be a design specifically developed from the ground up as an aluminium anchor.

The steel Spade is a fantastic anchor but unfortunately the aluminium version does not perform quite as well.

There are numerous user reports confirming that the aluminium Spade while a good anchor is not as good as the steel version. ManeSail produced a nice video showing how in identical conditions the steel Spade set where the aluminium version could not penetrate the substrate. This fits in with my underwater observations.

There have also been test reports confirming this. For example the large 2009 independent magazine test found the identically sized aluminium A80 and steel S80 recorded the following holding figures:

Steel S80 1705 kg Aluminium A80 1052 kg

The link is here, so you can read the report for youself and decide if the Steel and aluminium versions of the Spade have the same holding power.

https://www.georgekniest.nl/pdf/manuals/kobra.pdf

If, like BabaYaga you want a kedge or stern anchor the aluminium Spade is a great choice. In this application the lighter weight of the aluminium version is a distinct advantage. However, as a primary anchor the excellent steel Spade is a better choice.

It would be great to see some new aluminium anchors. The Fortress is a fantastic kedge or secondary anchor. Hopefully in the future will we see some top tier aluminium primary anchors that are also free of disimilar metal corrosion. I think anchors such as these could be produced with the right design.
 
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Noelex - if only you spent as much time on looking critically at your own anchor and its design as you do on the competition you might actually learn something.

You have been spruiking your anchor, and critisizing virtually everything else, omitting to mention your anchor is twice the size that Rocna would recommend...... Over twice the size that Spade would recommend and twice the size that Anchor Right would recommend. Sadly people believe you without question. I note on CF you still say that a big anchor is better at short scope - but cannot produce the numbers - again people do not question you.

I can see a 'commercial' mooring, from where I sit, installed under Classification Society approvals for Super yachts. The mooring is composed of 3 danforths specially designed to each have a fluke seabed angle of 22 degrees. This design has been chosen so that the anchors can be lifted, easily, for servicing. When they are lifted, they are at short scope. Most fluke/seabed angles of most anchors are 30 degrees, or greater. So... the low angle has been chosen to allow the anchors to be lifted at short scope.

Please produce your numbers.

Talking of anchor tests and results - unless the tests are conducted with knowledgable independent witnesses the results are of lower credibility.. You have constantly harped on about tests showing that anchors can be scaled, double weight, double hold (whereas I might suggest based on numbers, cautiously, that double weight, maybe be increase hold by 75/80%) - An examination of the procedure used to derive the figures you rely on clearly shows that on some tests a nylon rode was used and on another a steel wire and chain rode used. In yet another test in the same series polyester was used. You cannot compare the results of the tests - which is how the scaling numbers were produced. You possibly know that using an 'elastic' rode is to reduce snatch loads........

Unless this level of detail is available anchor test results need to be viewed with a lot of caution.

Returning to Baba - he uses his anchor as a primary - his mooring style, I deduce, is a bit like a Med moor.


Sometimes, most times, you can speak some eloquent rubbish.

The volume of air in a ballast chamber, after the lead is installed in the toe of an anchor, and a well fitting cap is welded on - is minimal. Most flukes are made from a minimum of 5mm steel, or aluminium. You have need to pressure test a water of fuel tank (few of which are made from 5mm steel or aluminium) - but there is simply no need to pressure test an anchor fluke where the volume of air is not even an egg cup and the retained air small. Furthermore when the cap is welded on the air is heated (welding is a hot process - in this case in a very confined space), and expands. When the ballast chamber is sealed the air cools and creates something near a vacuum - when the anchor drops into the Challenger Deep - I doubt the depth has any impact on the 5mm of metal which retains it.

If the pressure you imply existed then all the Ultra anchors would have exploded, or been crushed, many years ago. Its shank is hollow, made from relatively thin plate and sealed (and not pressure tested). I have heard of not one Ultra shank failing since the new fabrication methods were introduced (and they have not found the need for pressure testing).

Please spend some time reflecting on the number of people who have bought the recommended sized anchor of your recommended design based on your advice, where you have omitted to mention your anchor is twice the size of that recommended by your competitors. Please also reflect on those who might have believed your idea that a large anchor is safe at short scope - particularly one with a low seabed/fluke angle. You might also like to reflect on explaining why your anchor is 'so good' and merits your repeated recommendation - when it stands alone with a fluke seabed angle of 16 degrees vs every other anchor at 30 degrees.

If you have the numbers to support your contentions - please produce them.

Possibly you might like to underline that you don't actually have an 'anchor' as we understand the word -- you carry round a portable mooring. :) Our, the general public, anchors work by design NOT weight. Most of us do not want to spend excessive amounts of money carrying around ballast - we look for performance.

Enjoy Norway.

Jonathan
 
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noelex said:
It would be great to see some new aluminium anchors. The Fortress is a fantastic kedge or secondary anchor. Hopefully in the future will we see some top tier aluminium primary anchors that are also free of disimilar metal corrosion. I think anchors such as these could be produced with the right design.
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Apparently it is already under consideration, which you will be very well aware of - given both you and your wife are Moderators.

http://www.cruisersforum.com/forums...w-where-have-i-seen-this-before-218097-4.html

Post 51

If you look carefully you will see the design is in part, if not in whole, correcting the design fault in the Mantus. I'm not sure that he has gone 'far enough'.

Accepting the aluminium Viking is still a dream (as is the steel Viking) you could buy the aluminium Excel. It sells well in Australia, New Zealand and in America's Pacific North West. I believe it was also the anchor of choice on a spiffy, large, new yacht in build (maybe launched now) in Italy (I'll see if I can get more detail).

http://www.anchorright.com.au/products/sarca-excel-alloy-anchor/

The Excel has the seal of approval from a number of independent sources, including Morgan's Cloud (or AAC), if you are a subscriber. It merits note Morgan's Cloud are fairly consistent supporters of Spade, I don't know their views on the aluminium version. They are very anti 'roll bars' and along with Evan Starzinger stopped using their Rocna. Morgan's Cloud negativity stems from some expensive accidents referred to in brief below (in their intro to the Excel) but Evan never said, or I never saw it, why he stopped using his Rocna and replaced it with a (or 2?) big Bruce. Noelex - you will be pleased to note, I recall Evan saying (something like):

'No-one is going to tell me a smaller Bruce will be safer than my oversized Bruce!'

https://www.morganscloud.com/2019/02/03/sarca-excel-anchor-a-real-world-test/

Morgan's Cloud removal of recommendation for Rocna and Evan's change to a Bruce pre-dates this work, below, but this offers some indication of possible issues. Whether Viking will have a similar weakness we need wait and see. It would have been interesting to know (not anecdotally) why Evan changed as he is one of the very, very few (in my case only one I know) to have swapped a second generation anchor for a first generation anchor.

https://www.practical-sailor.com/issues/37_26/features/Anchor-Resetting-Tests_10981-1.html

Jonathan
 
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I think the Evan Starzinger decision was based on his testing on coral off Chile. The full test report was on his website some years ago: don't know now. His anchor was a Manson copy of a Bruce, called a Ray, very heavy for a 38 ft boat. He seemed convinced that this outperformed his Rocna although the two were not the same weight. I forget which was the heavier.
 
vyv_cox said:
I think the Evan Starzinger decision was based on his testing on coral off Chile. The full test report was on his website some years ago: don't know now. His anchor was a Manson copy of a Bruce, called a Ray, very heavy for a 38 ft boat. He seemed convinced that this outperformed his Rocna although the two were not the same weight. I forget which was the heavier.
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Practical Sailor November 2008 has an article including testing by Starzinger, Manson Ray and Supreme, Rocna tested on sand/mud/pebbles. It seems they also covered hard seabeds in the December 2008 issue but I cannot find that one. The anchors were massive, 60 kg or so.
 
vyv_cox said:
Practical Sailor November 2008 has an article including testing by Starzinger, Manson Ray and Supreme, Rocna tested on sand/mud/pebbles. It seems they also covered hard seabeds in the December 2008 issue but I cannot find that one. The anchors were massive, 60 kg or so.
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That rings a bell, hasn't that come up a few times - huge Bruce's performing well compared to other designs but not so great with smaller sizes around what most of us use.
 
GHA said:
That rings a bell, hasn't that come up a few times - huge Bruce's performing well compared to other designs but not so great with smaller sizes around what most of us use.
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I have heard the same thing - but never seen any evidence for, or against.

And Vyv - you have a very good memory :)

In contradiction - I see many, smaller ones on bow rollers (though this is hardly objective) and I know of people on here who use smaller ones, than 60kgs - who seem quite happy and sail in 'northern' UK waters.

I do hear they work much better in some seabeds than others.

In reference to GHA's mention of 'huge' - they were made in tonnage size, but I cannot recall how big. Variants, with twin shanks (ladder shank?) and fabricated rather than cast are still used - in these tonnage sizes and are rated SHHP.

Bruce don't scale very well when tested in bigger sizes - double weight and hold increases by 70% (not the double weight, double hold - believed by some).

When Peter Bruce introduced (around 1970) the anchor, for leisure vessels, they were a revelation - and promoted SL to invest in the design of the Delta, (introduced late 1980's).

Jonathan
 
noelex said:
There is a summary of the test here:

https://www.practical-sailor.com/issues/34_11/features/Heavyweight-Cruising-Anchors_5700-1.html

There is a longer and more detailed report published by Beth Leonard and Evans Starzinger, but I cannot find an internet link. Nevertheless, the above summary covers most of the points.
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Yes, that's the one I found. Anchor tests on beaches are somewhat discredited now I think. If I read the article correctly the December edition is about anchoring for real.
 
RichardS said:
Neeves - Noelex / Noelex - Neeves. :confused:

Richard
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Thank you Richard....

The difference is:

If you probe, me, I'll answer any query. I will offer practical tests I have done and practical tests done by others plus data from the industry.

Noelex will simply be unable to answer - will disappear - and re-appear repeating the same dangerous nonsense.

I challenge you:

Ask Noelex to justify the idea that an anchor larger (than recommended by the manufacturer) is safer at short scope than one of the recommended size.

Maybe you believe the concept - so you justify it to me. If you cannot justify it - why not ask for details - I cannot understand why such a simple concept does not merit a little bit of a probe. Frankly I'd like to believe it but.....Now - given a sensible reply I would learn - but I have the concept, but no background to support it.

Now if this does not appeal

Ask Noelex to explain what is the advantage of his anchor with a fluke seabed angle of 16 degrees vs every other anchor (except an 'altered' Fortress) that has a fluke seabed angle of 30 degrees. His anchor is unique - are you not fascinated that he can have a thread of hundreds of images - and not mention it once. Are you not interested in the implications.

People have bought this self same anchor - are they aware.

Now if you don't mind this sort of information being suppressed - I'm sorry. I actually thought this forum was here to allow these questions to be asked - and, importantly, answered - in this case by an, or the, expert.

Frankly there is something wrong if a member of this forum is allowed to make wild statements or omit, crucial, detail completely - and is then not held to account.

Its 'our' forum is it to be accurate and of great value - or something else. Are you saying one should not probe - because its impolite?

As I said ask me anything about something I post and I'll justify what I say - we might then agree to differ - but I will answer. I won't hide behind anonymity, I will take responsibility for what I say. I will accept when I am wrong - I'm not too old to learn.

But thank you for raising the issue.

Jonathan
 
vyv_cox said:
Yes, that seems to be their conclusion. Ray/Bruce under 44lb less reliable on setting. Which seems to support the findings of many anchor tests.
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Just a single (unscientific and anecdotal) data point:

The (quite experienced) original owner of my boat (35ft monohull, maybe 9 tons in cruising trim) originally equipped it with a 35lb genuine Bruce.

He wasn't happy with it (failing to set or dragging in quite moderate conditions I think) and upgraded to a 45lb (genuine) Bruce which he was much happier with.
 
Munz said:
Just a single (unscientific and anecdotal) data point:

The (quite experienced) original owner of my boat (35ft monohull, maybe 9 tons in cruising trim) originally equipped it with a 35lb genuine Bruce.

He wasn't happy with it (failing to set or dragging in quite moderate conditions I think) and upgraded to a 45lb (genuine) Bruce which he was much happier with.
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I can believe it but the article is comparing them with anchors weighing well over 100 lbs.
 
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