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Aluminum Anchors

5K views 25 replies 6 participants last post by  Fortress Anchors 
#1 ·
Aluminum Anchors provide a lightweight alternative to steel. Some, like the Fortress can be disassembled for stowage. These are reasonable factors for tackle selection. One important and less discussed attribute of these anchors is density and their actual weight under water. Design and size have much to do with the ability to set and holding power. Weight does too. A 32 lb. Fortress (FX-65) is about the same size as a 60 lb Danforth (60H). At 32 lbs. the Fortress weighs all of 19.8 lbs. when immersed in salt water. Under 20 lbs. The Danforth, being more dense as well as starting out heaver is 52.2 lbs. A Danforth of compatible dry weight, the 35 lb. High Tensile comes in at 30.5 lbs when submerged.

In some bottoms and in certain weather this may not make a big difference. If you boat primarily in the Chesapeake and ICW, smaller and lighter anchors may suit you. If you need an anchor to bite into weed, grass or hard bottom, you may want to consider steel. I am simply raising this point to, hopefully, enable better decision making.

While I discussed the Forterss/Danforth style, this goes for all aluminum anchors. They loose approximately 38% of their weight in salt water. Steel looses 13%. Subtract the percentage from the dry weight(DW) and you get the wet weight (WW). For aluminum - DW-(DWx0.38) = WW. This is for salt water which is 1.025 the density of fresh so the difference would be minimal.
I tend to run to the heavy side for a 41' sailboat. We have a 73 lb. Rocna on 3/8" D7 chain and a 55 lb. on 5/16" BBB on the bow. At the stern we have a 43 lb. Danforth with 3/4" nylon double braid. We anchor in a lot of different bottoms and in a lot of different exposures. We do sleep well at night.
All that said, choose ground tackle that you will be able to handle. If your windlass dies in a deep anchorage, will you be able to get anchor and chain back up? Make sure you try in good conditions before you need to in bad. All input is welcome!
 
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#2 ·
I know this situation quite well.

Many years ago it was Spade designer/inventor Alain Poiraud who insisted it was percentage of tip weight and anchor design that lead to optimal setting and not overall anchor weight..

I bought my first new gen anchor based on these claims and his arguments were quite sound.. The Spade A80 (aluminum) performed incredibly well, multiple times better setting than our CQR, but in a hard substrate it still had a tough time penetrating, nowhere near as bad as the CQR but still not great or the instantaneous/sets in its own length that Alain claimed..

A friend bought the same anchor only in steel not aluminum. He had zero issues on hard bottoms. The shape and design were absolutely identical side by side identical except for the anchor material. aluminum vs. steel or 35 pounds vs. 15 pounds.

When I contacted Alain he was boisterous, rude and in denial there was any difference between the two anchors. He basically called me an idiot...

I then borrowed my friends S80 and made four videos for Alain and sent them off. A week later I had an S80 sitting on my door step free of charge.....:wink I guess Alain agreed there was a difference after seeing the videos...

Bottom weight DOES matter in certain bottom types. I still argue that design is the priority when it comes to good setting but the overall weight also matters as it does between my A80 and my S80 Spades. My S80 Spade out performs our A80 Spade EASILY in hard bottoms. In softer substrates you can not tell the difference and both perform the same...
 
#4 ·
A 15 lb. Spade weighs a meager 9.3 lbs. in the water. If the bottom is loose or soft with no grass or weed you may get a set. It would not be an anchor I would want as I could never sleep at night! As with all things, sometimes designs are made using a given material and they function well. Then marketing comes in and has them create "the same thing" except in a lighter form. The new generation anchors all seem to perform well but weight still counts. Our boat is 41' and weighs 16.5 ton, the Rocna, at 63.5 lbs. submerged has been outstanding, even hooking in the limestone bottom in Alabaster Bay, Eleuthera. You could see where the tip dragged about 10 feet and then started to dig in. At about 15 feet it found a flaw and set with about 10-12" buried. We ran in reverse to 2300 RPM and as the wind was SE for the next couple days, called it good for the night. I am still a big fan of weight. Any anchorage that has lots of current, heavy tides or exposure to wind and waves requires an anchor that resets quickly. Heavy really helps with that. An aluminum anchor, unless it was a monster, will have a harder time of it. However, gunk-holing in the Chesapeake, there are times we used our lunch hook, a 20 lb. Danforth and were happy as eels in a pond overnight. In the ICW other than some high current areas, it would likely be fine.

As far a design goes, I disposed of a Bruce and a CQR, I think those types are now a part of history. The new gen anchors have really shown how good they are in a wide range of bottoms. The Fortress/Danforth will likely remain because of their folding design.
 
#5 ·
As far a design goes, I disposed of a Bruce and a CQR, I think those types are now a part of history. The new gen anchors have really shown how good they are in a wide range of bottoms. The Fortress/Danforth will likely remain because of their folding design.
It might be hasty to discard Bruce/Claw.

I've been doing some quantitative anchor testing for an up-coming article. The focus is 2-anchor systems. Sure enough, pivoting fluke and scoop anchors dominate in mud bottoms, which was supposed to be the focus of the article (how to stay still with what you've got in really soft mud). The Claw did not put up big numbers...

... Until I started looking at rocky bottoms. Suddenly the best anchor changed (a 12-pound Northill outperformed a 25-pound Delta every time). Sometimes I was anchored by the roll-bar, something the designer may no have envisioned.

Just sayin', based on limited knowin'.
 
#6 ·
I don;t know, the Bruce especially was temperamental in a lot of bottoms. I never cared much for a Delta we had and the CQR doesn't stack up to what the Rocna can do. We have used all these anchors up and down the east coast and the islands. Quantitative testing is good, necessary in fact, but is not real world. What I felt I needed many years ago was a quiver of anchors. Given limited space but room for two anchors on the bow, I went through a bunch of anchors finally settling on a Bruce and CQR on the Bow and a 65H Danforth on the stern. More often than not, I used the CQR so I abandoned the Bruce when we got a Rocna. Now that I have seen what this anchor can do, I not only feel justified in disposing of the Bruce but dumped the CQR in favor of another, slightly smaller Rocna. I now don't see why my back up anchor shouldn't be as good as my primary! I still have the Danforth on the stern and it has been useful both as a kedge and in "busy" waters. I will not say we have never dragged, we have, but only while setting. Once we have a set, no, we have never dragged anchor (knock wood, tap tap tap three times....). We always back down hard, feel the chain, get visuals if we can and now we always use DragQueen! We have woken up with another boat on us. First was a delta, second a Bruce and the last some kind of Danforth that was about 8 sizes small. Everybody has there preferences and ideas on anchoring. I just never heard the discussion about how much weight an aluminum anchor lost compared to steel and thought I would bring it up.
 
#7 · (Edited)
a. The Bruce/claw sucks on soft bottoms. Needs to be massively over size.



b. Rocna failed embarrassingly in soft mud testing. No set in most cases, only one that would hold in a 15 knot breeze. Other scoop anchors did better. Just sayin' no anchor does everything perfectly.

Why did it fail? One theory is that there is not enough weight towards the toe, and in soft mud the roll bar doesn't quite work. Strange, since the Manson Supreme set every time.



I understand aluminum for Fortress, which is a specialist soft bottom anchor. For general purpose, aluminum doesn't seem to work out, for all of the reasons given by others.

The other think I have learned testing anchors is that while clear water and clean sand make for pretty pictures, muddy water and groping after anchor buried in soupy, smelly mud is more educational, but not so popular.

Also look at the long setting distances. It isn't dragging, that is the extended setting process in mud. Interesting.
 
#8 ·
"b. Rocna failed embarrassingly in soft mud testing. No set in most cases, only one that would hold in a 15 knot breeze. Other scoop anchors did better. Just sayin' no anchor does everything perfectly.

Why did it fail? One theory is that there is not enough weight towards the toe, and in soft mud the roll bar doesn't quite work. Strange, since the Manson Supreme set every time."

Interesting data. Of course, the test sponsor was Fortress. While I can not dispute their data I can say that our Rocna has never failed, certainly not in mud. At Sandy Hook, NJ we had 35 to 40 kn winds and water coming over the bow and the anchor held. Outside Cuttyhunk, MA we had 30 to 35 Kn with some higher gusts, the seas were "lively" and it held. In Governors Harbour, Eleuthra Bahamas we had 25 to 35 kn and it held (sand over limestone). We anchored in the flats of Rock Hall, MD in 20 to 30 kn winds and did fine, other than the rocking. These, and others, are really the "tests" I am more concerned with. The only time we had any issue was when we dropped on a old crab pot in Albemarle Sound. Once I removed the pot it held fine! Other cruisers that I have talked with that use a Rocna have much the same to relate. Anchors do have attributes to lend themselves to certain materials and situations. They are also only a part of your ground tackle system. The biggest part is still your brain. Understanding what you have and how to deploy it properly is the single most crucial part. Knowing what the prevailing conditions are is critical as well. I use a heavy, large anchor (73 lb.) with proven characteristics and tie on to it with a heavy chain rode (3/8" D70). I allow plenty of scope, considering tide, wave action, current, wind and nearby vessels. We always back down on the set (usually at 2300 to 2500 RPM, 55 hp.) and always keep some kind of watch (DragQueen is excellent). No doubt this may not work somewhere but so far so good!
 
#9 · (Edited)
Interesting data. Of course, the test sponsor was Fortress. While I can not dispute their data I can say that our Rocna has never failed, certainly not in mud.
Why are we all conspiracy theorists?

a. Fortress failed to set too.

pg

b. The most reliable anchor was Manson (best weakest set result).



c. Just because Fortress came up with a few quid to sponsor a test on mud (a pivoting fluke anchor will always put up the highest maximums--undisputed fact--so it was a safe bet that they would look good) does NOT mean the test crew was biased. They had good people on board, and I would not insult them by implying something ugly. It is good data. And your sainted Rocna will fail in this mud unless it is over size, just like every other anchor. Sorry, but this mud has been described as Kleenex, so soft on the surface that you can barely feel it with your hand, like thick water. Nothing really holds unless it is huge.

Let's not have a chip on our shoulder. The fact is the Fortress design is mighty in sand and mud, and poor in everything else. Accept it. Scoop anchors rotate better and handle more bottoms. And ALL of the anchor manufacturers puff their products.
 
#13 ·
"...Just because Fortress came up with a few quid to sponsor a test on mud (a pivoting fluke anchor will always put up the highest maximums--undisputed fact--so it was a safe bet that they would look good) does NOT mean the test crew was biased. They had good people on board, and I would not insult them by implying something ugly. It is good data. And your sainted Rocna will fail in this mud unless it is over size, just like every other anchor. Sorry, but this mud has been described as Kleenex, so soft on the surface that you can barely feel it with your hand, like thick water. Nothing really holds unless it is huge.

Let's not have a chip on our shoulder. The fact is the Fortress design is mighty in sand and mud, and poor in everything else. Accept it. Scoop anchors rotate better and handle more bottoms. And ALL of the anchor manufacturers puff their products."

Please, lets be a bit less judgmental and condescending. I have not insulted anyone nor do I have a chip on my shoulder. I simply pointed out a fact. Fortress WAS the sponsor of these tests, they paid for them. The tests are no doubt as unbiased as most. I believe I have also, reiterated, all these anchors have their place. Because I have a preference, based on years of experience including nearly a decade living on the hook, doesn't mean I have a chip. It means I have definitive reasons NOT to prefer certain anchors and specific justifications for using the ones I do. The Fortress and Danforth are great anchors in mud. I carry one. It is steel because I believe the weight is an advantage, especially in mud. When I set my anchor in mud I use series of jerks that seem to set much quicker than steady pull. I am very aware of some of the methodology and standards in military testing, again from experiance. Not that it is true in this case, but in the past I have been involved with some that were "less than optimum" lacking proper base lines, controls or consistency. Tests are interesting and can give you some useful indicators but, given the hundreds of times we have anchored in mud with our Rocna without any difficulty or drag, what real practical use are they to me now? Especially when I have the same results in sand, sand and shell, gravel, weed, grass, loose rock and limestone in storm winds, heavy currents and breaking seas.

I think every sailor needs to do their own research, read the test results, read forums and get experienced opinions, go out and try different anchors and talk to real people who have used a plethora of tackle. Then they need to make their own judgement.
I just want to add to the knowledge base and have folks consider the attributes of aluminum and steel insofar as density and actual weight under water. What may feel heavy enough in the store won't necessarily be on the bottom.
 
#14 · (Edited)
Nolex: The drag speed was 10 feet per minute, not 10 feet per second. That is 5cm per second. To correct for the substrate difference (drag-in distances in this mud are 5-10 times further than sand) we need to reduce that relative velocity to less than 1 cm/s, and then the correction factor becomes 15% of so; a rounding error in a variable bottom, if we look at the variation between tests. In sand, I agree, static and moving are vary different, and my testing agrees. I agree that SHF and UHC are not the same; I stated that winch tension always falls off--in fact in this ooze it is difficult to get UHC at all. Could you calculate UHC in silly putty, which is a fluid? The answer is of course you could not. So I agree with what you have said whole heartedly for sand and most mud, but look how low these numbers are and accept that this is just barely a solid. It is a special case and I believe the numbers are valid, based on repeating some of the same tests in the same area.

It is well known in this area that leaving an anchor soak (gravity will press it down better than pulling sometimes) helps, just as it does for a mushroom anchor. Knox's formula does not work for that effect. An anchor would do something similar in silly putty. Complicated.

The other factor to consider is that all anchors faced the same procedure. Trends are trends.

The Knox web site is interesting. Lots of good stuff. Interestingly, his conclusion about snubbers and the test results I have gotten are a perfect match. The same math and experiences, no doubt. However, testing on a send beach and testing over soupy mud have little in common. I've been testing in-line tandems over rocks, and that brings a whole nuther' set of questions and problems; random rock breakage, the effect of tiny veers and bucking on hooking, and differences in how chains wrap around. Just crazy, but fun to watch under load!

Windnrock: "Interesting data. Of course, the test sponsor was Fortress. While I can not dispute their data I can say that our Rocna has never failed.... " Yes, the second sentence did retract some of the implication. However, in this case all Fortress did was encourage the testing to happen in what was likely to be a good substrate for them; no sponsership, no testing, and they like to show off their power in mud. This area is locally known for terrible holding, and they wanted to show it could be done. No tricks; I've seen every sort of anchor drag here. Fortress wouldn't sponsor a test over weeds, would they! What you make of the data is up to you.

The truth of anchor testing, no matter how detailed, is that the biggest variable, by far, is always the bottom, and it makes good data on real bottoms confoundedly difficult to get. Yes, you can get good data in regular sand, but frankly, for most of use, that is irrelevant, because we won't drag when anchored in good sand or sandy mud. It is the crappy bottoms that get us.

I think it is clear that this group knows that performance varies enormously with the situation. All I did was present some data showing a well-documented situation that is very different from typical sand data. I have a Fortress and I don't use it very often for obvious reasons. This is a place where it works... though you do need to be prepared to make a second setting pass--that's just part of the compromise.
 
#15 ·
To recap what I said in my initial post: Steel is a good choice from a standpoint of weight as well as durability in rocky anchorages. Aluminum is good for handling and therefore ease of stowage. A point to consider is that aluminum looses 38% of its weight in salt water (very slightly less in fresh) steel only loses about 13%. New anchor designs, while not perfect in all bottoms, cover more varieties than ones we have seen in the past. What fits one sailors needs will not fit another, however, my personal experience as well as that of many others (including the US Navy) has shown that weight makes a difference. I chose as heavy an anchor as I felt comfortable with (considering weight of chain in a deep anchorage or about 50')hauling in by hand. In making your choice realizing the difference in submerged weight between aluminum and steel is important. The Fortress 32 lb. anchor weighs only 19.8 lbs. submerged while the Danforth 35lb. weighs 30.4 lbs. and are similar in size and performance. If you find yourself in harder ground, weeds or grass, this extra 10.5 lbs. might help. Other anchor types are more suited to different and broader spectrums of bottom types. The types and how many are your choice. With 3 years of near constant use, I have found the "saintly" Rocna works very well for us.
 
#16 · (Edited)
Gents:

Excellent input on this topic. A few comments and notes from the Chesapeake Bay testing:

- The results of this extensive 4 day test left no doubt that the capability of widening the shank / fluke angle (in the case of the Fortress, from 32° to 45°) will dramatically increase the holding capacity in soft mud.

While Fortress holds a US patent for the two hole crown which allows for this feature, it is no secret among large manufacturers such as Bruce, Baldt, Vryhoff, and the US Navy, as they all make anchors with a wider shank / fluke angle for improving performance in soft mud.

- While anchor size and weight can play a role in initial penetration and holding power, if the anchor does not have an "effective fluke angle," by which the fluke(s) aggressively engage the bottom, then a larger physical size and heavier weight can be minimized or even negated.

We saw this firsthand with one of the "new generation" anchors, as with its huge size, everyone aboard had expected that it would perform extremely well, but since the fluke bottom was relatively flat, the anchor basically skated along the soft mud bottom and it did not develop much resistance in almost every test.

- Robert Taylor is a retired US Navy anchor design and soil mechanics expert, with over 45 years of experience in this field, and he served as a consultant for us on this project. I shared the John Knox information with Bob, and he offered a long dissertation about Knox's theories, which I can summarize with his comment, "One cannot use factors created for sand and apply them to test results in mud."

- There has been some discussion in this thread about the value of anchor weight, and here is something else to consider: If you take two anchors with roughly the same physical size and design, and one weighs significantly less, but it is precision-machined for sharpness, then which anchor would you expect to penetrate faster and deeper in common sea bottoms such as sand, mud, or clay?

This is exactly the case between a Danforth and Fortress, and the lighter weight Fortress has consistently demonstrated a significant advantage over the Danforth in a wide variety of tests, dating back to the 1989 US Navy test (where the Fortress also proved to be structurally stronger), in setting and holding power capability.

- Regarding the Fortress vs. other designs, there can be little question that in some difficult bottom conditions, such as grass, weeds, or rocks, a very dense anchor with a single narrow fluke is likely to penetrate more effectively than the two massive flukes of the Fortress.

On the other hand, there can also be no doubt that once a Fortress is properly buried in common sea bottoms (sand, mud, or clay, once again), then those two massive flukes will be much more difficult to break free.

We certainly saw this in the Chesapeake Bay, as the 21 lb FX-37 was by far the most difficult anchor to bring back aboard, particularly vs. the 44-46 lb new and old generation anchors, and we lost one FX-37 when we were pulling on it at a 1:1 scope and the wire rope broke at 3,500 lbs.

You can find several of the magazine stories and videos from the testing on the web page below:

Fortress Anchors ? The World's Best Anchors! ? Chesapeake Bay Anchor Test

Safe anchoring,
Brian
 
#17 ·
Has Fortress considered tests with "more challenging" bottoms? It would be of interest to have tests conducted with shorter scopes as well. Because of the range of bottoms I experience in our cruising I need an anchor that has more versatility, for the lack of a better word. I have seen people struggle in some areas and in some situations a Fortress/Danforth style anchor is useless. Of the two boats that have dragged into us, one was on a Danforth and the other a Fortress. Granted there are numerous variables but it does raise ones eyebrows! It could be the perfect anchor for someone who boats primarily in the Chesapeake or areas with mud or sandy bottoms and I do have a High tensile Danforth on my stern (60 lb.). Has Fortress considered making steel anchors with the same design? We are live-aboard cruisers and as this is our only home, space is at a premium. The two anchors I have on our bow must have the ability to do well in most bottoms and conditions, maybe not the best, but very well. I can no longer count the number of anchor sets we have done. I can say that with the current anchors we have, I can count the retry's on two hands. Every product is not for everyone but if another person drags into us with "that" type of anchor, I will personally write you! Also, while I appreciate the honesty,"as the 21 lb FX-37 was by far the most difficult anchor to bring back aboard, particularly vs. the 44-46 lb new and old generation anchors, and we lost one FX-37 when we were pulling on it at a 1:1 scope and the wire rope broke at 3,500 lbs." I don't necessarily view this as a "good" thing! Thanks for your input though and I hope to maybe see you folks at the Annapolis Boat Show.
 
#18 ·
windnrock;2934097... tests with "more challenging" bottoms?...[/QUOTE said:
Serious question. What would you suggest, and how would you define them so that there was any fairness? I swear I am not being sarcastic. I've been investigating just this. It is a bugger in my humble opinion.

Fortress. I see it as a superb single-purpose sort of tool, just like a socket wrench is great for one size nut, so long as it has 6 sides and the bolt is not too long. Much better than pliers... unless you are trying plumbing, in which case a pipe wrench might be better. There is no point in disparaging Fortress for weakness in rocks. That simply is not what it is for.

Scoops. I didn't mean to disparage Rocna. It is a great anchor in most bottoms. But I've worked with Mantus, and it may be better in sand, and Manson may be better in tougher bottoms. Rocna was trying for an over-all design and they certainly opened some eyes. But those are only my opinions based on limited testing, and the differences were small.

But back to your point. We need a way to sort these things. For example, I noticed that on certain rocky bottoms a Delta is terrible, the "delta" gliding over small but suitable cracks and rocks. Every other anchor I tested on rocks (no pivoting fluke) worked fairly well, even some old designs (Nothill), but it really came down to the exact spot and specific drag path.

Grass is a similar problem; the anchor that is lucky enough to find a weak spot wins. Testing on actual turf might be interesting, but of course, turf is also quite variable.

Cobbles and shingle are interesting. No idea how to define them practically.

Ideas? Not just "they ought to....."

Ideas?
 
#19 ·
Like any test that has difficult controls it would have to take place over time with lots and lots of sets. That is how I have come to select the anchors I have. While the tests were not formal and there was a lack of uniformity, the experience over the course of years did show certain pieces of equipment to be superior in a wider range or to be singular at one bottom type. I've been in areas where a grapnel hook would have been best! An analogy I would use would be the testing of metals. Given every piece is unique due to the crystalline structure of metal, collecting data is difficult. You can use single crystal models to give you a baseline but even that is off because a single crystal behaves differentially. So you test over time and the collected data builds, bad data points are eliminated and eventually you can get results that reflect actual conditions. How is the metal being used? Tensile, torsion, flex, high pressure pipe, under corrosive conditions, high heat, low temp? The myriad of applications and conditions make testing a real challenge. It certainly can't be done is a few days or even weeks. It also brings to mind the rating of an anchor for a particular boat. What is used? Length, which might seem reasonable enough given the vast number of different boats. However, even that is just a guess, for all the same reasons. I have a high mass 41' sailboat with relatively low freeboard and narrow for her length. She will behave much differently than a 41' trawler or a 41' planing hull sailboat or any two 41' catamarans! And so the variation continues. In skiing we measured the correct length of ski for years by your height. Until someone figured out skis didn't care how tall you were but were more "concerned" with your weight.
Ultimately one has to decide what the purpose of the testing is. Does it achieve that goal and is that goal made clear to the end user? I think there is more than a little hubris as well as marketing in the "Fortress anchors, the worlds best anchors?" statement/question/implication. The worlds best anchor could be construed as one of the 120,000 lb. anchors the navy uses! Given the wide range of application there is no singular "worlds best", that is clearly up to the application and conditions, not marketing. The question remains, what is any anchor really and honestly best at? This goes for ALL anchors. That needs to be defined, so when a consumer who has done their homework and gives clear parameters of their needs, can select what is really best for them.
I do not think Fortress anchors are bad anchors, quite the contrary. I believe many people will find them to be very suitable to their application. I think the whole "best anchor in the world" thing is over the top. Based on tests like the Chesapeake tests the anchor clearly shows it's ability in mud. It also shows there could be a potential problem in recovery! Granted marketing may not want to use the phrase, "so good you may have to leave it behind!" but that is a test result.
So PDQ, to answer the question:
The test needs to be done on varied bottoms, with a wide range of boats, both in type, shape and size, in different conditions with wind, current and seas. Additionally, different types of ground tackle and scope need to be applied and every anchor needs to see the entire range a number of times. Well, not to practical, but it is a goal to shoot for and interestingly enough is going on out there right now. The only problem is that data is not being collected! This is where we come back to my boats, my tackle and my experience over the course of decades. While I don't have specific data, I do have knowledge covering much of what I laid out above. There are also thousands like me (frightening no?) who have the experience, no specifics per say, but "situational instances" over time. Talking with many of those people, who I know are in my similar situation and have similar vessels, allows me to do some additional comparative analysis and build on my experience. The tests that are done are necessary for a number of reasons but much of it does fall into the marketing category. In real life the results are different. It is very much like approaching an unknown inlet, you have a chart but you could also go with local knowledge. I will always go with the local knowledge.
 
#20 · (Edited)
The "local knowledge" statement is where we are left. The problem is that becomes full of myth, tradition, and stubbornness.

You idea is intriguing--that only though lots of feed back can we learn--but unlike cloud sources depth data, the sailors aren't going to collect enough data:
* what was the bottom
* did they dive on every set
* what was the rode/scope
* what was the depth
* how many degrees did the wind veer, over what time period
* what was the load (load cell required)
* what was the sea state

My concern (conclusion?) is that 95% of the cloud source data would be statistically useless.

Sorting the data is painful with one boat and just a few locations and bottoms. Open up the scope and you are back to "local knowledge." In my case, since I have dragged only a very few times in many years, I could conclude that all anchors are good. But I know that some of those sets probably held by the skin of their teeth, and most were such protected conditions a bucket full of rocks would have held.

Yeah, I'm just going to get one of those Navy fleet anchors. That should do it. I wonder if they come in aluminum (staying on-thread).
 
#21 ·
Partial quote, PDQAltair - "The "local knowledge" statement is where we are left. The problem is that becomes full of myth, tradition, and stubbornness.

You idea is intriguing--that only though lots of feed back can we learn--but unlike cloud sources depth data, the sailors aren't going to collect enough data:
* what was the bottom
* did they dive on every set
* what was the rode/scope
* what was the depth
* how many degrees did the wind veer, over what time period
* what was the load (load cell required)
* what was the sea state

Sorting the data is painful with one boat and just a few locations and bottoms. Open up the scope and you are back to "local knowledge." In my case, since I have dragged only a very few times in many years, I could conclude that all anchors are good. But I know that some of those sets probably held by the skin of their teeth, and most were such protected conditions a bucket full of rocks would have held."

Absolutely correct. However, by selecting the information source carefully and avoiding the known "myth, tradition, and stubbornness" factors, i.e. a reliable sailor that you know or know of their methodology, you can actually have fewer variables than expected. Many sailors, like myself, make log entries concerning anchoring (tackle, bottom, scope). Combined with the weather and current data collected, it can give a more accurate picture. Nothing is perfect so we apply the same tactic used in construction; when you select a two by four, how do you know it will give the performance it is specified to give? It is wood and therefore, unique to a degree. But it is over engineered and the loads given are under the theoretical maximum. That is my approach to anchoring. I use an anchor that through my research fit my particular set of needs and comes highly recommended by experienced sailors that I know, the Rocna, it is two sizes over the recommended and as heavy as I feel comfortable recovering by hand (73 lb.), I use all chain 350' 3/8" D7 with a bridle and I drive it into the bottom with as much force as I can apply. Then, whenever possible I visually check it. If I feel the situation warrants it, I have two more anchors I can set, one (50 lb.), again a Rocna, on all chain (5/16" BBB) the other, a Danforth (60 lb.) with 25' of 1/2" chain on a 300' 7/8" rode. I can set tandems, oppositions or even run an additional 300' rode to shore. We also carry a 25 lb. Danforth "lunch hook". We can set out up to 4 anchors and also tie to shore if necessary. Overkill? Perhaps, but this is our home and we wist to be able to secure her no matter what the conditions. With unknown bottom structure, the possibility of debris and having to use reduced scope my conclusion came to be "weight". So, what do the commercial tests of anchors mean to me? Very little. They are, to some degree, useful to folks who are just starting out. They do need to be balanced with practical, even anecdotal information. It is like science,"pursuit of the truth with never believing you are in possession of it". One day I hope to find a lightweight anchor that will hold in any bottom, under all conditions and return to the boat pristine and easily!
 
#22 ·
This is a very intriguing discussion, although I do not expect that a consensus will ever be reached. Having the "right tool for the job" is vitally important, as I think we can all agree, at least in principle, that no single anchor design will perform optimally in all bottom conditions.

As I recall, those aboard the 81-ft Rachel Carson research vessel were quite surprised by the poor performance of many of the highly-touted new generation anchors in soft mud, but as Bob Taylor noted, anchors that are designed and optimized for harder soils will oftentimes only have a holding ratio (anchor holding capacity divided by anchor weight) of 10-15 in a soft soil, and that is almost exactly what happened in the Chesapeake Bay testing.

I have found that owners of new generation anchors will dramatically oversize them in comparison to the old generation models that they left behind, so the performance of the new generation models in poor holding bottoms, such as soft mud, has not been notable. Obviously, if the owner of a 45 lb CQR upsizes to a 73 lb Rocna, then he will typically experience an increase in anchor performance.

Since cruisers worldwide have successfully used CQR and Bruce anchors for decades in a wide variety of sea bottoms, one has to wonder whether the performance advantage of a new generation model is limited to larger sizes and in specific bottoms. As an example, will a CQR or Bruce, which do not have a roll bar that will possibly impede penetration, out-perform a comparably sized Rocna in grass, weeds or rocks?

Regarding the boast of being "the World's Best Anchor," no other anchor in the world has consistently achieved the incredible holding ratios of the Fortress in common sand, mud or clay bottoms.

Fortress anchors have regularly out-performed anchors that are 2x their weight, and if a pound for pound test was held, say between a 70 lb Fortress FX-125 (currently the primary anchor aboard the USCG 110-ft and 154-ft patrol boats) and a Rocna of comparable weight, then the difference in holding power in common sea bottoms would be nothing less than astounding.
 
#23 · (Edited)
Taking it one paragraph at a time. My comments are preceded and followed with ******.
This is a very intriguing discussion, although I do not expect that a consensus will ever be reached. Having the "right tool for the job" is vitally important, as I think we can all agree, at least in principle, that no single anchor design will perform optimally in all bottom conditions.

*****However, some will do better than others in many bottoms and work sufficiently well in the rest. That would be my point. It is a compromise of sorts. Like a crossover bike, I get reduced performance in some areas so that I can travel in all*****

I have found that owners of new generation anchors will dramatically oversize them in comparison to the old generation models that they left behind, so the performance of the new generation models in poor holding bottoms, such as soft mud, has not been notable. Obviously, if the owner of a 45 lb CQR upsizes to a 73 lb Rocna, then he will typically experience an increase in anchor performance.

*****I typically use my smaller 50 lb. Rocna as opposed to the 60 lb. CQR and Bruce we used to have. I carry heavier equipment for situations that may require it. In some respect I find I am an aberration and contrary to your statement, most of the cruisers I know, as well as many boats I see on our journeys actually tend to go with the recommended sizes. Some power boats, even smaller.*******

Since cruisers worldwide have successfully used CQR and Bruce anchors for decades in a wide variety of sea bottoms, one has to wonder whether the performance advantage of a new generation model is limited to larger sizes and in specific bottoms. As an example, will a CQR or Bruce, which do not have a roll bar that will possibly impede penetration, out-perform a comparably sized Rocna in grass, weeds or rocks?

*****As you state, cruisers worldwide have used CQR and Bruce anchors for decades in a wide variety of sea bottoms. If they are so successful why are people getting new anchors? Indeed, why get a Fortress? Me, I found the Bruce as well as the CQR to be pretty useless in weeds and grass, even my large ones. It would take effort and trial to find a good spot. The smaller Rocna does much better. On hard rock bottoms (limestone in the Bahamas) they were likewise problematic. Like you say, we used these anchors for years, mostly because the alternatives were lacking. Often we had to resort to "quivers" of anchors and diving to jam it in somewhere. My heavy Rocna actually cut into the limestone. I gravitated to the new anchors because they are more useful and reliable in a multitude of bottoms. The same sort of tests that may say the Fortress is superior to others in mud have also shown the new anchors out setting the old. For decades most cruisers have used Dacron line successfully, that does not mean we shouldn't look into and use the new fibers.*****

Regarding the boast of being "the World's Best Anchor," no other anchor in the world has consistently achieved the incredible holding ratios of the Fortress in common sand, mud or clay bottoms.
Do you mean, "The worlds best in soft soils without vegetation"? While marketing is great, a modicum of accuracy is greater still and more benificial to the end user. I would not flatly call ANY anchor "the worlds best". Best for what? I mean what about a 30 ton MarkII stockless, wouldn't that rate a best anchor?*****

Fortress anchors have regularly out-performed anchors that are 2x their weight, and if a pound for pound test was held, say between a 70 lb Fortress FX-125 (currently the primary anchor aboard the USCG 110-ft and 154-ft patrol boats) and a Rocna of comparable weight, then the difference in holding power in common sea bottoms would be nothing less than astounding.
***** While I dislike the "If" in you assertion, Laconic or otherwise, tests are interesting. What "if" those tests were held in many of the poor holding bottoms that are, in my travels, commonly found? Heavy weed and grass, sandstone and limestone, baby heads and the like? There many anchorages I would prefer a new gen over a heavier Fortress or Danforth! Your point about the FX-125, I am not sure why should I care about what a 110 ft or 154 ft. ship uses? How often do these CG vessels ride at anchor if at all and where? Are their requirements anything like mine?

Succinctly put, it is your product and you are proud of it, rightly so, I dispute the "worlds best moniker" because you have test that show its capacity in some bottoms but wash over the fact they are NOT effective in others. More importantly I have tried many anchors in many anchorages including Fortress and I have now found the "best anchor in the world" for MY needs, if not a Rocna then a Manson, Manta, Spade or Knox, at least until someone, somewhere comes up with something else. *****
 
#24 ·
Windnrock,

Thanks for your comments and input. Here's some further thoughts:

- Excellent analogy with the crossover bike.

- Only a fool argues with success. Your anchor arsenal has been well battle-tested, and it has kept you safe in your cruising grounds. It would certainly benefit other cruisers to take note of these anchors that have worked well for you.

- My comments about other anchors are simply based on discussions and observations, and they were not meant to be taken as gospel. I continue to see the old generation models adorning the bows of many cruising sailboats, and oftentimes with very satisfied owners. I suspect that these older anchor models have simply met their needs and so they have not felt the need to switch and upgrade.

- "The World's Best Anchor" boast will always stir up controversy, which we expect and accept. The reference to the USCG vessels was to indicate that the FX-125 had to meet a very high performance standard, particularly for a 70 lb anchor, to be approved for use aboard such large vessels.

- On a separate note, during the past 18 years I have observed that cruising sailors have purchased Fortress anchors for specific use as a stern, kedge, or back-up storm anchor, particularly in hurricane regions.

All the best,
Brian
 
#25 ·
I accept "World's Best Anchor" as an advertising claim--defensible in many circumstances--to be perfectly acceptable puffing. Do we really believe that "Coke Adds Life" or that everyone that goes to McDonalds is "lovin' it?" A lot of "Best" claims are like that, and so long as they are true some of the time they are fair advertising practice. Nothing more, nothing less.
 
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