Dare I Say Another Anchor Article

The friendliest place on the web for anyone who enjoys boating.
If you have answers, please help by responding to the unanswered posts.
See posts with no answers
Peter---- Yes, but...... Compared to the size and weight of the vessel a chain made up of one-ton links is still light and tiny. And look at the windage of the thing. Sure, its tremendous weight gives it an inertia that takes time for the wind to overcome. But it will eventually overcome it and move the ship around.

Now I'm absolute rubbish at math, so correct me if I did this wrong. A 44 pound anchor is .0014 percent of 30,000 pounds, which is the weight of our boat. A tanker that weighs 400 million pounds (200,000 tons which seems to be the average size for a typical large tanker--- but not an ultra large one) would also need an anchor that weighs .0014 percent of its weight, which would be 560,000 pounds, or 280 tons. Now maybe the anchor of a ship this size weighs that much, I don't know. They don't look it, though....
 
Last edited:
manyboats said:
BandB,
How could it be "independant" when it says "Peter Smith" at the top of the page in the web page window. Can't imagine anybody more biased about the Rocna anchor that Peter Smith.
Click to expand...

It obviously isn't. I didn't know the history. And the Independent is just the link as it posts. But actually the tests themselves may or may not be independent. One would have to decide that. I'm sure given the situation, he didn't include tests that reflect badly on Rocna.
 
BruceK said:
Unsurprising. It could complicate things.
Click to expand...

Yea, it's no fun at all to compare your anchor in a "unbiased" test with another anchor that is in the same category.

Omit the competition to make yourself look better???

Funny because the side by side tests I saw that The SARCA inventor put on at least had the Rocna anchor in them, even though they showed the Rocna to be a pretty good anchor itself!
 
ksanders said:
Yea, it's no fun at all to compare your anchor in a "unbiased" test with another anchor that is in the same category.

Omit the competition to make yourself look better???

Funny because the side by side tests I saw that The SARCA inventor put on at least had the Rocna anchor in them, even though they showed the Rocna to be a pretty good anchor itself!
Click to expand...

Yes, but, shockingly, the Sarca tests show the Sarca topping the Rocna. lol.
 
Sarca doesn't go beyond 320 lbs do they? So no classed boats beyond 100' or so? I know Rocna builds up to 606 lbs and even beyond if required.
 
Britannia said:
But is that actually true? Let's run some numbers.

Here's a short article on anchor chain on the Triple E class freighter from Maersk

Anchor chain for the world’s largest ship is so big it makes humans look like mini figurines | 22 Words

It says that the links on the anchor chain weigh over 500 lbs each. Now the links on my anchor chain weigh 0.25 lbs each (8 links to the foot, 2lbs per foot). That makes the chain on the container ship 2000 times heavier than my boat.

The Triple E class container ship runs 55,000 tonnes displacement empty (https://en.wikipedia.org/wiki/Maersk_Triple_E_class) My boat is 31 tonnes dry, making the Triple E about 1800 times heavier than my boat.

It seems to me that the anchor chain, at least, appears to be roughly in scale to the size of the boat/ship.

I haven't found the weight of the anchors for these behemoths yet.

Richard
Click to expand...

Emma Maersk (similar size E series ship) has a 130 tonne anchor. My anchor is 50 Kg. Emma's anchor is 2600 times heavier than mine. Still seems like we're in roughly the right ballpark for size.

Richard
 
BandB said:
Sarca doesn't go beyond 320 lbs do they? So no classed boats beyond 100' or so? I know Rocna builds up to 606 lbs and even beyond if required.
Click to expand...
Clicking "Anchor Right Products" on the Anchor Right Australia website, brings up a group of pics of boats with anchors. One pic appears to be of a fair sized ship, in dry dock, but I could not get it to load and enlarge.
 
Here is a link to a document setting out a few anchor parameters.

https://www.amsa.gov.au/forms-and-publications/domestic/publications/documents/NRIP00092.pdf
Chapter 3 is the interesting part.

For Marin and others who wonder about ship anchor sizes, the standard defines 'Equipment number" and gives an equation with a number of variables. Basically Equipment number is a function of displacement, frontal area and profile area.

In addition, a document from a Wollongong, NSW workshop held in 2014 that considered the impacts of anchoring off coal ports whilst waiting to be loaded contains some items of interest. The document "Anchors aweigh: workshop summary" included the statement below as part of their overview of anchoring.

Anchor designs are numerous, however, the weight of the cable, or anchor chain alone ultimately hold the ship in position. A ratio, relating to the length of anchor chain to the water depth varies depending on the size of the vessel, from 3-5:1. Each link ~200kg contributes to an anchors holding capacity. Depending on ocean currents and wind, ships may swing around the point at which the cable rises from the seabed.
 
Insequent said:
……...Anchor designs are numerous, however, the weight of the cable, or anchor chain alone ultimately hold the ship in position. A ratio, relating to the length of anchor chain to the water depth varies depending on the size of the vessel, from 3-5:1. Each link ~200kg contributes to an anchors holding capacity. Depending on ocean currents and wind, ships may swing around the point at which the cable rises from the seabed.
Click to expand...


See my post 27, P2. Suggests my impressions were probably correct, and yes, as Marin says, supports the all chain rode choice if practicable.
 
Marin said:
Brian-- Sort of makes the case for all-chain rode doesn't it?:)
Click to expand...

Definitely for larger vessels. And I think for most of our pleasure boats as well, although at the smaller end of the scale and where tension anchoring is used (Northern Spy's post earlier) maybe it isn't necessary. Eric kinda proved he doesn't need it for Willy. But would he be more secure with chain....;)
 
Ever hear the USCG captain of the port order broadcast to all ships in an anchorage to bring on line their power plants to avoid dragging when the winds rise ?


I think 35 knots of wind for the order is pretty common.
 
Insequent said:
Definitely for larger vessels. And I think for most of our pleasure boats as well, although at the smaller end of the scale and where tension anchoring is used
Click to expand...

And that is the point I think. For larger vessels.

If the same was true for smaller vessels, (and by that I mean under say 200' or so) that chain does most all the work in keeping a smaller boat anchored, all you'd need is a mushroom anchor at the end of your chain to hold the chain down. Which in my option, after using several large ship style fluke or navy anchors on smaller vessels over the years, are little better than. In my experience with them they drag and don't set well even with all chain rode.

So in my opinion, while nice to have, chain alone isn't the be all end all of anchoring.
 
psneeld said:
Ever hear the USCG captain of the port order broadcast to all ships in an anchorage to bring on line their power plants to avoid dragging when the winds rise ?


I think 35 knots of wind for the order is pretty common.
Click to expand...

Yeah, cause fluke anchors, just like the Bruce :), are known draggers. :D
 
Yep...because ...I don't think the ships really carry ground tackle to anchor in conditions that smaller vessels experience IN PROPORTION.

If they do experience proportional conditions, they have the crew to motor against the forces or get underway and head for sea.
 
BruceK said:
Clicking "Anchor Right Products" on the Anchor Right Australia website, brings up a group of pics of boats with anchors. One pic appears to be of a fair sized ship, in dry dock, but I could not get it to load and enlarge.
Click to expand...

I see them but then in the list of anchors the largest shown is size 15-145 kg. Perhaps they do custom make larger just as Rocna does. I have emailed them out of curiosity to ask.
 
How can an anchor be "best" if it's performance at typically short scope (3-1) is poor???

If you were to pick a "best" car it would have to perform at an excellent level in all commonly encountered conditions. With crowded anchorages .. and small anchorages .. and deep anchorages .. and 10 to 20' tides, how is one to do much anchoring w/o needing good short scope performance. In the real world that I know short scope performance comes up time and time again.
Most all anchors have excellent performance at medium to long scope. Many have excellent performance at short scope so why would someone choose an anchor that has been repeatedly shown to be weak at short scope?

The Manson Supreme has excellent SS performance and is only 5 to 10 % shy of the Rocna's spectacular long scope capability. A best anchor MUST do all things well and the only thing I can think of as a weak link for the MS is the roll bar fitting on the bow problem. But the Rocna has that problem too. The Anchor Right Excel could be the best anchor (or the Mantus and several others) but an anchor needs history and many anchors are lacking history or/and consistently suburb performance in many to most anchor tests. People value anchor tests. If not the Rocna would not be sold in large numbers ... and Peter Smith is very aware of that. The recent test linked in this post is obviously a response to the Fortress test this summer. And I think it's very slanted to the Rocna.

So the best anchor for certain people w boats compatible w roll bars may be a roll bar anchor but to be overall "best" that negative feature would be IMO unacceptable.

So in proven anchors what does that leave us for "best anchor candidates"? A steel Spade. But the Spade is recorded as weak at short scope. That leaves the Fortress and it is imperfect as well. There is no perfect anchor of course but the OP called for "best".


For a skipper willing to accommodate the roll bar installation problem one could have "best" in the water anchoring performance from only one anchor. Manson Supreme is the only one that performs supremely (pun intended) in all ways. So I'll label it best.
With the new Excell, a new Spade, Mantus and several other newbies history and anchor tests down the road could reveal a new "best" and even quite soon.
 
Well said, Eric. But is the criteria for the "Best" performing anchor going to be holding power? In the recent test by the great folks over at Fortress, I think I recall that in the test of the FX-23, the unit burried itself beyond reasonable recoverability, becoming a sacrificial anchor. I love my Fortress, but is recoverability part of its anchor performance criteria? Does it fit most pulpits? What other performance criteria should there be in addition to holding power at this or that scope for a given boat with a given rode and an assumed "equal" bottom anchoring point? Nope....I don't think the playing field can be level enough to name a "best" anchor unless one unit is so far above everything else as to leave the rest in the dust (or mud, as it were).
 
Last edited:
Well, I think Eric nailed it :)
 

Attachments

  • Bow pulpit.jpg
    Bow pulpit.jpg
    113.8 KB · Views: 102
healhustler said:
Well said, Eric. But is the criteria for the "Best" performing anchor going to be holding power? In the recent test by the great folks over at Fortress, I think I recall that in the test of the FX-23, the unit burried itself beyond reasonable recoverability, becoming a sacrificial anchor. I love my Fortress, but is recoverability part of its anchor performance criteria? Does it fit most pulpits? What other performance criteria should there be in addition to holding power at this or that scope for a given boat with a given rode and an assumed "equal" bottom anchoring point? Nope....I don't think the playing field can be level enough to name a "best" anchor unless one unit is so far above everything else as to leave the rest in the dust (or mud, as it were).
Click to expand...

Healhustler, thanks for your comments. During the testing we lost an FX-37 after we loaded it up to 2,000+ lbs, and per the winch operator's calculations, it was buried 13 ft into the mud.

During retrieval, we were directly above the anchor and pulling at a 1:1 scope, but the research vessel moved sideways a bit, and the wire rope slipped between the horizontal and vertical rollers on the custom-made fairlead. At that point, we had metal on metal, and the wire rope snapped at 3,500 lbs.

Yes, I have heard previously the Fortress being referred to as a "sacrificial anchor" and it is certainly possible after a serious blow. Stories have been sent to us about fossils and dinosaur bones and even a Chinese gardener coming up with the anchors after a heavy storm, although that last one had to be an exaggeration. :facepalm:

Regarding the "independent testing" on Peter Smith's site, I have voiced objections to them about the inaccuracies concerning our product, but to no avail. Suffice to say that we will not be exchanging Christmas cards, once again, this year.

That said, I have read and heard stories about their anchor performing well for boaters, and kudos to them for making a product which has helped to keep boaters safe on the water.

All the best,
Brian
 
Larry,
Yes of course holding power. But holding power accross the board under as many different conditions and situations as will be or should be encountered. Holding power in sand, gravel, rocks, grass and at scopes that are universally used. Holding power with or w/o a lot of chain weight. I've heard quite a few times that Kedges and Dreadnought anchors don't "need" chain. How true or to what degree I don't know. My Dreadnought does have a very heavy shank. Variables that the "best" anchor should be able to deal with gracefully ... or at least well. Again the best should be an excellent all around anchor. Another contender if Roll bar anchors are to be considered at all (and a good case can be made for not considering them) is the SARCA. Not the holding power king but a good performer at all scopes and with no faults that I know of except that it's a roll bar anchor. The very fact that the manufacturer didn't rest on the SARCA design and offered the alternative Excel speaks loudly that it wasn't a perfect design much like the Rocna and Vulcan.
 
QB said:
A strange comment, since they are essentially identical, except for recent marketing.
Click to expand...

Really? Different materials, mud palms and 2 settings on Fortress. Great factory support too. ? Maybe fluke geometry is equivalent? Dunno.

I still have my FX-33 as a spare, and FX-55 in bag as ultimate spare.
 
BandB said:
Here is an interesting compilation of some of the anchor tests.

Independent Anchor Performance Testing
Click to expand...



Seems to cherry-pick data, after complaining about others cherry-picking data.

And perhaps I read too fast, but I think the West Marine chart is saying the Fortress pulled up to 5000-lbs, while the Sail Magazine article from the same tests says Fortress was a hair over 2000 lbs. The author goes on about aluminum being weaker than steel, "no less than two Fortresses were damaged and put out of action"... but in the grand scheme of things damage after 5000-lbs pull doesn't seem all that much a bad thing, to me.

He complains about comparisons being mis-matched because anchors are of different sizes... but then the data is presented in graphs that tend to downplay size and focus only on holding.

Interesting read, some of the factoids seem very useful by themselves, but some of the conclusions seem OK and others, not so much.

No surprises here, though.

-Chris
 
ranger42c said:
Seems to cherry-pick data, after complaining about others cherry-picking data.

And perhaps I read too fast, but I think the West Marine chart is saying the Fortress pulled up to 5000-lbs, while the Sail Magazine article from the same tests says Fortress was a hair over 2000 lbs. The author goes on about aluminum being weaker than steel, "no less than two Fortresses were damaged and put out of action"... but in the grand scheme of things damage after 5000-lbs pull doesn't seem all that much a bad thing, to me.

He complains about comparisons being mis-matched because anchors are of different sizes... but then the data is presented in graphs that tend to downplay size and focus only on holding.

Interesting read, some of the factoids seem very useful by themselves, but some of the conclusions seem OK and others, not so much.

No surprises here, though.

-Chris
Click to expand...

Like reading any of them. There is no such thing in life as totally unbiased. And then he is totally biased. Still some of the information is worth looking at. I did not realize who he was at first, but I'm sure not going to put things on a website that makes my own company look bad.
 
QB said:
A strange comment, since they are essentially identical, except for recent marketing.
Click to expand...

QB, the design and dimensions of the anchors are close, but the materials, weight, manufacturing/machining/finishing are all vastly different. As previously noted, the adjustable shank/fluke angle is a big difference/feature, for which Fortress holds a US patent.

ranger42c said:
Seems to cherry-pick data, after complaining about others cherry-picking data.

And perhaps I read too fast, but I think the West Marine chart is saying the Fortress pulled up to 5000-lbs, while the Sail Magazine article from the same tests says Fortress was a hair over 2000 lbs. The author goes on about aluminum being weaker than steel, "no less than two Fortresses were damaged and put out of action"... but in the grand scheme of things damage after 5000-lbs pull doesn't seem all that much a bad thing, to me.

-Chris
Click to expand...

Chris, there are many misrepresentations and omissions from those tests which were not reported on that site. As an example, you mentioned above that Peter Smith wrote "no less than two Fortresses were damaged and put out of action." which is totally false.

I could provide more details, chapter and verse, but I don't wish to air out dirty laundry publicly any further.

Additionally, I think he would be farther ahead to take the approach "all anchors are great, and mine is even better," rather than spend time disparaging other products.

Regards,
Brian
 
Last edited:
Fortress Anchors said:
Additionally, I think he would be farther ahead to take the approach "all anchors are great, and mine is even better," rather than spend time disparaging other products.

Regards,
Brian
Click to expand...

You're so right.

Everyone would be that, regardless of the business they are in. It never raises you up by putting your competitor down.
One can point out what makes their product great and simply say that's unique and the consumer will look at the other products and realize they don't have it.

I will say this. I strongly dislike companies or individuals creating additional websites to promote their product without full disclosure of the connection. It's done constantly and in poor form I believe.
 
Last edited:
You must log in or register to reply here.

Similar threads

Greg QS
Anchoring again
2
Replies
49
Views
5K
Meander
M
mpstan
Rocna Mk I vs Mk II
Replies
3
Views
423
High Wire
High Wire
klee wyck
Stern anchor
Replies
17
Views
2K
psneeld
psneeld
Hardship
Ultra anchor issues
2
Replies
31
Views
5K
SteveandZoila
SteveandZoila
mncruiser
Rocna Vulcan problems
2 3 4
Replies
119
Views
15K
Trawlerdream
T

Latest posts

Back
Top Bottom