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Old 10-06-2014, 06:25 AM   #741
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Originally Posted by Peter B View Post
Jonathan, small but important point of order here, but all the reports of hoops and/or flukes clogging would, I strongly suspect, be of those on anchors with concave flukes. As far as I know, my Super Sarca is the only hooped anchor with a convex fluke. Thus far, and in bottoms with what I call 'weapons grade' sticky mud, my roll bar has never clogged.
Peter, I stand rebuked.

I am guilty as charged.

You are correct, I have never seen (or heard) any report of a convex, roll barred anchor that has clogged in sticky mud and specifically (as I think it one of a kind) a SARCA nor the more recent Super SARCA. But I have also never heard of a Knox clogging (but I suspect there are not many out there, maybe give them time) nor a Bugel (or its copies) of which there large numbers. And whilst on the subject, no mention of clogging of a Spade nor Ultra. The Ultra seems to come up super clean, the Spade can sometimes have a little compacted mud (nothing to comment on) but whether this is due to the Ultra being stainless or some design feature - do not know.

The reason for mentioning the Spade and Ultra (more the Spade) is that the upper surface of the fluke of Spade is very similar, strikingly so, to the upper surface of the Rocna. The angles are the same (the Spade is rounded a bit more, the fluke 'plan' the same - so the mechanism seems to be the roll bar. Edit, unless the weighted toe is also advantageous at 'stopping' clogging. close edit

But to be fair many owners of the Rocna and Manson suggest that the 'clogged' fluke is indicative that the anchor is working and setting up compression. So it is a well recognised phenomena.

Jonathan

another edit

and talking of eating cereal with an upturned spoon:


When the Delta was introduced (and the Bruce had been around for a few years by then and I suspect making inroads) Simpson Lawrence used to give lectures on their new Delta. This must have been in the early 90s. The party trick was take a tennis ball and a Bruce and ask someone in the audience to catch the tennis ball in the fluke of the Bruce (they breed them tough and strong in Glasgow). Apparently with great success. They then asked anyone in the audience to catch a tennis ball with the Delta.

The argument is as old as the hills (and Scottish hills are pretty old).
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Old 10-06-2014, 07:34 AM   #742
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Good post. If I understand you correctly, I would take issue with this last, in that I can't see how a large anchor is ever less efficient than a lighter one. If you look at the ratio of weight to surface area of the Ultra as an example you can see what I mean. A 46# anchor has a "holding surface" of 50 cm2 per pound. My 176# anchor has a holding surface of 32 cm2 per pound. Which is more likely to dive the deepest - the one that has less weight per square cm it needs to bury or the one with more weight per square cm? Clearly the later. If this reasoning is correct, and I can't see how it is not, then the heavier the anchor the deeper it will bury. Your point about requiring more force to get the anchor to bury is of course correct. I think what that means is that as the force on the vessel increases, the more holding power a diving anchor will develop with the heavier developing the most holding. This is the fundamental reason I go on about the only limitation I see in hoop style anchors - if they don't dive, their maximum hold is static so what you get setting it in 20 knots is pretty much what you'll get in 80 unless it drags and hits something solid.

I've always assumed this is why the big Claw I had worked so well, 100% of the time. It was heavy enough relative to its surface area that it always dug in deep, while a lighter Claw would not have done so.

By the way, does this mean you are finally willing to admit you are not a Zulu warrior???
In answer to your question on bigger is better. A bigger anchor can develop a higher hold than a smaller one. No doubt.

However whether the large anchor can realise that potential will depend on the load.

To be extreme, a 30' vessel simply does not have the windage to set deeply a 200lb anchor. That same vessel can fully set and bury a smaller, say 5lb,anchor. If the anchor was 'too' small that anchor will dive (its a modern anchor) and reach its maximum holding power potential and swim through the seabed (until it meets a bit of weed or shell - upon which it will surface and drag). Somewhere between that tiny swimming anchor and the monster that cannot be set deeply is the ideal - one that under no normal condition can reach that swim depth (and its maximum holding potential) but can get close to that full potential. Anything bigger than that ideal is simply ballast and a hole in your wallet. (and extra money for the anchor maker)

Anchor size charts have been developed over decades and have initially been based on pretty inefficient anchors. Modern anchors are now twice (I do not want to get picky) as good yet the weights are the same for the new, twice as good anchors, as the old anchors - and those old anchors were found to be 'about right'. We consequently seem to have doubled the safety margin (which is no bad thing). But we also, in general, are a bit more adventurous (and go further) so maybe that doubling of the safety margin might have been whittled somewhat. We also can carry more anchors which might return that safer margin.

But basically if a 100lb CQR/Bruce was good enough then a 100lb Rocna/Spade/Excel ought be equally good enough, if not twice as good.

Some say that a Bruce works better in bigger sizes, I have a friend who says they are superb beyond 70kg. I simply do not know - but this may be dependent on seabed.


I make it look black and white (which it definitely is not) - but hopefully you get the idea.

We went the other way and use an anchor slightly smaller than might be recommended (because the recommendation is based on worst case scenario) and our anchor is very, very good. When we get to, looking like, worst case scenario we deploy a second anchor (different style but same capacity), in a 'V'. Its a personal choice works for us, has done for years - not too many agree, they prefer bigger is better and in the extreme 'ridiculous is better'. There is nothing wrong with RIB - its just extra ballast and that hole in your wallet. (and I think of seaworthiness in big breaking seas when you are on passage). Now whether we need the extra anchor, in our V, I do not know - we are cautious and prefer to stay where we are and have never had the courage to test it.

The reality is that we never hear of modern anchors dragging in most seabeds as a result of them being too small (though many when they upgrade also upsize). So we hear of dragging, in weed where the anchor cannot penetrate - but not because the anchor was small (unless its mud). Consequently the evidence seems to suggest that BIB might allow you to sleep better, but might be unnecessary - and RIB is well R.

So if you know of anyone with any modern anchor that experienced dragging as a result of it being too small it would provide some background.

I'd welcome comment


Sorry no Zulus, just thick skinned Celts.
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Old 10-06-2014, 08:18 AM   #743
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Chris, would it be possible for you to beaf up the pulpit either side of the central manufacturers slot…(thinking stout timber lengths, screwed and epoxied in underneath), then mount an auxiliary free-standing roller to one side - maybe both sides - then you could have two other options open to you. I guess it would depend on the overall width of the pulpit platform at the outer end. If you added a sort of bridle loop over the top of each roller, that would prevent the anchor skipping off the roller. Just a thought.

Cheers,

Thanks. Maybe. I continue to mull. I forgot to mention the centerline spotlight complication (improving the pulpit sides may help with that), but in any case my hesitance is also taking into account the part about how to make it all look acceptable (or at least not goofy), too

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Old 10-06-2014, 08:22 AM   #744
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So if you know of anyone with any modern anchor that experienced dragging as a result of it being too small it would provide some background.

I do see often boats drag around here... but can't say it's because of anchor size.

Aside from the occasional soft/soupy/slimy mud issue, though, it seems most often to be about technique. Or lack thereof: drop the anchor, open a beer, we don' need no steenkin' "setting."

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Old 10-06-2014, 10:37 AM   #745
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HFS -This thread has turned into the silliest mud slinging (bottom composition pun intended) and spit ball throwing mess I've seen since 2nd grade. Come on now - guys - we're all grown ups, yet too many of these posts are becoming so repetitive and nonsensically condescending regarding what anchor, or what portion/design of what anchor is better that the other... or no good at all for that matter... there is little sense any longer being made. Newbies to this site must be simply shaking their heads in total confusion from the silly "cat fights" occurring on this thread!

Get real!

There are a bunch of good anchor designs represented here. Each has its own high points and not-so high points. But, each has its place in the marine industry as well as its need or attraction to different boaters.

All in all: "Different Strokes for Different Folks!

Haven't you all just about worn out the repetitive innuendoes about how others' anchors are just no damn good?? Face It - They are all good in one way or another!
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Old 10-06-2014, 11:42 AM   #746
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In answer to your question on bigger is better. A bigger anchor can develop a higher hold than a smaller one. No doubt.

However whether the large anchor can realise that potential will depend on the load.

To be extreme, a 30' vessel simply does not have the windage to set deeply a 200lb anchor.
I'd welcome comment.

I'm not sure that makes sense Jonathan. Using your example, the reason the 30' vessel wouldn't 'set' the 200# anchor is because it wasn't able to drag it so that it could engage the sea bed. If it can't move it a few inches to start that process, doesn't that mean the boat is anchored securely? If it were tied off to a mooring buoy it wouldn't be able to drag that either, but that is kind of the point. You are correct that in the small boat/big anchor scenario the potential holding capacity of the anchor may not be reached, but who cares if the reality is that the boat cannot drag the big hook so as to explore that potential?

Again, I cannot see how an anchor that has more weight per unit of surface that engages with the sea bed, of whatever gross weight, is not superior to a smaller anchor of the same design that has a lower weight per unit of surface area. I think the argument not to carry an anchor that is too large is one of weight on the bow, so I've always thought the rational approach is to carry the biggest hook you can carry that you can afford and that your ground tackle can handle. Which isn't to say you can't get fantastic holding from a smaller hook that digs in, just that that holding will be less than if the anchor were weightier.

On the question of Bruce types working better at heavier sizes, that has been my experience. I can tell the Ultra I have now is set better than the same size Claw because I have to get right over the thing to break it free from the sea bed, but in terms of holding, the Claw never failed in up to 55 knots of wind, while I have experience with a 44# Bruce dragging a couple of times over 20 years.
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Old 10-06-2014, 05:54 PM   #747
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I have taken the liberty of cleaning up the mess in the Anchor Aisle. You've had your say, now let's get back to anchoring, Pleeeeaaaaaaasssssse! Please be careful...our anchor shoppers are a sensitive lot.

Thank you!
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Old 10-06-2014, 06:10 PM   #748
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Delfin

The little vessel with the monster anchor is 'well' anchored. The point I was trying make was that the monster anchor is unnecessary and thus a waste of money. You might need a bigger bow roller, windlass, which means more power, maybe new cables etc. Obviously if you have money in plenty and the vessel will handle the humongous anchor then why not - but its not working as it was intended, part of its hold is simply weight - because it has not been pulled below the surface by engine or wind. Most new anchors are designed to dive and when they do dive they develop increased hold (because the shear strength of a seabed increases with depth - the seabed is more compacted with depth).

An anchor that dives and pulls its shank down with it (obviously) looks a more secure bet than a larger anchor with its shank exposed or only in the loose upper layers. In a sideways load the shank will offer no or little restriction to movement if it has no seabed support. Equally the more chain you can bury the more chain you need to pull through the seabed - sideways - before the anchor is impacted.

If you take a chain and lay it in the seabed and pull it in a straight line its easy to pull (depends on how much chain and how strong you are). Take the same chain and now try to pull it sideways and what was possible in a straight line is now impossible (now think of the same chain buried).

Most new anchors now appear to be developed with hard seabeds in mind, which is why they have very sharp toes. Contrarily the Bruce appears to have been developed for a softer substrate, and maybe a specific regional softer substrate, as it has a very blunt and extensive toe and leading edge.

Manyboats has made the point that anchors, or his anchors in his seabeds, do not dive - my experience is the opposite. I see the chain disappearing into the sand - and no sign of the anchor at all. Sometimes I lose 10' of chain. I remind anyone we use small anchors. If I want to take a picture of my anchor underwater I need to take it when set at around half revs, if I use full revs I generally will not see the anchor. This obviously depends on seabed - and Eric might only anchor in hard seabeds. We do have hard seabeds, but they are murky and I cannot take pictures.

To reassure Art, I believe all anchors work in sand - its the peripheral areas that cause the issues (and many never experience soft mud, cloying clays and light weed with no bare sand patches). But the more we know of the limitations of various designs the more informed decisions that can be made - so thanks to Fortress we have a small piece of the rather large jigsaw in place.

Some anchors work better in these marginal areas and defining which anchors are better in these marginal areas seems a meritorious focus. In the meantime - anchors are a compromise.

But I'm still awaiting posts of people who have dragged because their anchor was too small. Most people I see use anchors of around the recommended size, some (a minority) go up a size (which is neither here nor there). But even the people who rely on the anchor recommendation charts, with modern anchors, are not prone to dragging (and some of these people go to pretty outlandish places). In fact the comment that is common (though I cannot quote them) 'we used to regularly drag our CQR/Delta/Bruce but now we have our Supreme/Excel/Spade we never drag and sleep at night uninterrupted' and these are people who have replaced weight for weight or maybe gone up one size.

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Old 10-06-2014, 06:15 PM   #749
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Carl,
Can only guess what Draggo had in mind design wise but like everyone else he probably was trying to design a better anchor. He sorta thinks surface area is everything but the most interesting and important element of his design is the minimizing of weight and appendages that are not fluke. The shank has to be the smallest in the world and the "righting mast" is not large .. partly as it starts at the top of the shank. It's clearly smaller than a roll bar. So the percentage of the anchor that is not fluke is so small the fluke area is bigger than any anchor. No other anchor (in this respect) gets closer to the unattainable holy grail.
But yes the early XYZ was not pitch stable enough to set .. very often.
The only XYZ tested since then was the wide tipped mud version that has a tip that wants to ride up rather than down so it dosn't set either.
The XYZ I have works very well for me but I lay my rode down carefully and have not put it to extremes enough to say it would be a super anchor.
I have w my modified XYZ but that's not on the market and is a specialty anchor that probably won't work on rocky bottoms or perhaps others.
So I think the XYZ may be a very good anchor but have no grounds to say w any degree of certainty. I don't think I've recommended it to anybody.
I intend to modify the XYZ fluke tip yet again to make it a more general purpose anchor.
But re your comment Carl yes I think the original XYZ was a diver and perhaps the current narrow XYZ Extreme is too. Don't see any other anchor that has more potential.

Carl I don't see how you can say an anchor is a diver because it's out of sight. A diver (I would think) would "dive" down a foot or so ... not an inch or so.

Jonathan,
I use almost exclusively smaller anchors (under 20lbs for a 30' boat) and have never dragged.
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Old 10-06-2014, 06:21 PM   #750
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To provide some balance to the assertions that convex anchors pile up sand and concave anchors do not here are some images that show the exact opposite:

Photos of Anchors Setting. - Page 71 - Cruisers & Sailing Forums

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Old 10-06-2014, 06:27 PM   #751
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Jonathan--- I think you've made a fair statement (your post #734). I think everyone would agree that no anchor will perform perfectly in every conceivable situation. Fortress' soupy mud test illustrates that.

When I say I think the Rocna design, or perhaps I should broaden that to the overall rollbar anchor concept, is the "best in the world," in my mind, at least, I am allowing for those situations where the design did not perform as well as others for various reasons.

But to me, if we say that a 95% success rate is what is experienced with the rollbar anchor family in all the conditions under which it is used, that'a a hell of an enviable success rate to my way of thinking.

You're in a position to hear a lot more about anchor performance than I am, but in my experience, observation, conversations, and reading, other anchor types don't seem to enjoy this same success rate.

I fully agree with the notion that if one is going to encounter anchoring conditions for which one's primary anchor is not very well suited, carrying an additional anchor that IS suited to these specific conditions is a smart move. Hence the Fortress FX-23 on our swim step.

Regarding Al and other's feelings about this overall thread, it would be interesting to know WHY anchors evoke such long and passionate discussions on forums like this.

My own opinion is that, like one's boat itself, an anchor is a chance for a boater to express his or her individuality. Like vehicles. I despise anything made by GM, others think GM is the only way to go.

Also, an anchor is a bit of mystery. It does its work unseen to the majority of us. And the unseen/unknown has always had a fascination for people, with a great deal of effort being put into speculating about it, and defending what one believes about it.
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Old 10-06-2014, 07:57 PM   #752
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Marin I guess I owe you an apology.

I've poo poo'd your comments about Rocna's popping up all over the place for years as I haven't see that. But this afternoon I went to see the new Spades as Fisheries Supply is listed as a dealer. No Spades. Not even any old Spades and the guy hadn't heard of the new Spades. Rocna's all over the place. Lots of big SS ones w flukes about 3/4" thick. 175lbs or so. I said oh well but it looks like you're well set up to sell me a Rocna. He said yes he sells more Rocna's than anything else.

So you were/are right. Lots being sold. Didn't ask him what size he was predominantly selling. But the place looks less like Fisheries Supply and more like a Rocna store.
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Old 10-06-2014, 08:37 PM   #753
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Eric---

Regardess of what one may think of Peter Smith as a person, he (or somebody at Rocna) did a very smart thing a number of years ago when they began having Suncoast Marine in Vancouver manufacture Rocna anchors along with the original fabrication facilities in New Zealand.

In fact when I first talked to Rocna in New Zealand to learn more about their anchor, they were the ones who told me that Suncoast had just started manufacturing them, and that it would make more sense for me to get one from them instead of from Rocna in NZ because of the huge shipping cost to send a 44-pound anchor across the Pacific. They also told me that some of Suncoast's manufacturing processes were more advanced than their own down in NZ.

In those days, Suncoast would only make a Rocna to order. They did not make them on spec. So we talked to the owner of Suncoast and ordered up a Rocna 20. They made one for us and when it was ready we drove up to Vancouver and picked it up.

The advantage to Rocna was they now had a toehold in the North American market. I may have events in the wrong order here, but Suncoast subsequently began making and supplying anchors to West Marine. Somewhere in here the company called Holdfast got involved, and to make the Rocna's price more competitive they moved all production to China. So as far as I know, at that point Rocna fabrication ceased in both NZ and Vancouver.

Then came the materials screw-up with the Chinese fabricator and Smith's, and perhaps even more so his son's, ill-conceived efforts to cover it up, which in the end really tainted the ancor's and the company's image and brand. Finally, the Rocna manufacturing rights were taken over by Canadian Metals.

But the point is that quite awhile back, Rocna established a North American presence, and despite the rocky road that ensued for awhile, that presence continues, and continues to grow.

West Marine has been carrying them for a long time now. I did not know that Fisheries Supply has also jumped on the bandwagon, as I've never wandered into their anchor section when we've visited the store.

Where I first noticed an increasing number of them was in the big Seaview North yard in our marina. They get a lot of boats from outside the Bellingham area, and once they acquired their 175 ton Travelift, they began hauling some real monsters, purse seiners and yachts and stuff. And more and more, I began seeing Rocnas on these things. Not the purse seiners, but the yachts and smaller recreational boats, power and sail.

So good move on Rocna's part all those years ago, to get a North American presence going pretty early on.
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Old 10-06-2014, 09:51 PM   #754
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Marin,
You wrote ", to get a North American presence going pretty early on." ..... Early on would have been about 1910. But the've been making anchors for hundreds of years. Anchors didn't start w Rocna.

Got to admit those Rocna's sure looked good. Great big SS pieces of art. But I like variety and Fisheries lacked that to be sure.

As to marketing Rocna has done well. I'd rather have a Supreme even though the Rocna's look better. I'll see how my mod goes on my small Supreme and then perhaps replace my Claw w a bigger Supreme. I bought the first Supreme w that in mind.

I've got other things to worry about now ...... like getting my engine to start. May still be air in the lines .. still. Took the whole system apart and changed numerous things. Better have the engine running when we get to the slings.
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Old 10-07-2014, 12:32 AM   #755
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Marin,
You wrote ", to get a North American presence going pretty early on." ..... Early on would have been about 1910.
Early on for the new gen anchors from Australia-New Zealand.
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Old 10-07-2014, 10:11 AM   #756
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Below are links to the stories that have been written and posted so far about the Chesapeake Bay anchor testing. More will follow from PassageMaker, Sail, and Soundings magazines:

All at Sea:
Best Anchor for the Chesapeake Bay? - ALL AT SEA

Boat US:
The Fine Art Of Anchoring - Seaworthy Magazine - BoatUS

boats.com
Fortress Anchor Testing: When It’s Good To Be a Stick in the Mud | boats.com Blog


Unfortunately, the only writers still aboard the final day were from Sail magazine, and I think one of the most surprising moments of the testing occurred when the 10 lb (4.5) kg Fortress FX-16 was pulled a few times. Fortunately this was caught on video, and I posted a link previously.

I mention this because it adds to the discussion about whether "bigger is better." The FX-16 when set at the 45° angle had comparable holding capacity to our 21 lb (10 kg) FX-37 when it was set at the 32° angle, and so "bigger was not better".......and outside of the Danforth, the FX-16 out-performed all of the other anchors that had a huge weight / size advantage as well.

So how is that even possible? Bob Taylor, who has spent 45+ years in anchor design and soil mechanics, much of which while he was in the US Navy, answered with the below when I asked him that question:


"Bigger is not always better, it has a whole lot to do with anchor configuration. A big anchor can be very unstable (Vryhof anchors have stability problems). An anchor with the center of area/pressure on the fluke that is very close to the shank to fluke connection can be very unstable. An anchor configured such that the fluke orients itself close the direction of pull such as the cast Bruce and copycats and a number of Stevin types do not take full advantage of the large fluke area available.

Increasing palm size helps to increase the fluke bearing area by causing the fluke to rotate down during pulls in mud. It is really all about configuration.

Thinner shanks help mostly in hard soil but you have to be careful that you don’t wind up destroying the anchor on its first off line pull.

Bob Ogg/Danforth and Dick Towne/STATO and the British Admiralty did some great work many years ago to understand the influences of seemingly minor changes in anchor configuration to anchor capacity. I studied all their work with huge interest because I wasn’t interested in reinventing the wheel.

As I mentioned awhile back I took a Bruce model anchor being tested in mud at Bruce’s facility in Scotland and more than doubled its capacity by a simple addition of a sheet metal plate to the back of the anchor fluke. All it did was cause the fluke to rotate down a little."
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Old 10-07-2014, 10:46 AM   #757
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Marin in 1975 the "new generation" anchor was the Bruce. Everybody was raving about this amazing new anchor. They appeared on the bows of boats like magic. Soon almost everybody had a Bruce except a few that stuck to their Danforths. And the Waggoner cruising guide guy recommended skippers get one before heading to Alaska. It held oil derricks before and could easily hold one's boat. And it was good on all bottoms. How could one go wrong?

Yup there's been many generations of anchors. There's nothing new about new anchors ........... except they are new now. And then they are not. The Danforth and the Claw have been mainstream for 60 and 40 years. Being 74 now I'll not see if the "new gen" of anchors achieve a legacy like that.
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Old 10-07-2014, 10:57 AM   #758
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Brian wrote;
"As I mentioned awhile back I took a Bruce model anchor being tested in mud at Bruce’s facility in Scotland and more than doubled its capacity by a simple addition of a sheet metal plate to the back of the anchor fluke. All it did was cause the fluke to rotate down a little."

Before my recent mod that I have in mind this is what I had in mind doing as I felt the Claw lacked fluke surface area. And down is always good. But I threw it out in favor of a more roll bar like addition in the interest of insuring that all three flukes buried and the anchor seldom if ever would lay on it's side acting like a plow. And I also thought it may pitch the anchor up. This could be happening w the up elevator trailing edge of the Rocna.
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Old 10-07-2014, 11:34 AM   #759
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Brian,
The mag articles were interesting in that given the same input such different opinions and text resulted.

By far IMO the first article was most overwhelmingly meaningful. And thus far I hadn't picked up on this part ... "After great debate and careful consideration to all anchors in the test, Hawley agreed to a change in the protocol in round five. The anchors were launched with an initial scope of 2:1 then pulled in 20 feet at 30 feet per minute until a load of 200-300 lbs. of torque indicated the anchor was set. From there the 8:1 scope was let out and the test resumed as normal. First up was the Fortress FX-37 at 45 degrees."

This seems really strange to me.

Firstly the most commonly held philosophy of setting anchors, even embraced by P Smith is to let out long scope and set the anchor. Then shorten up for swing and other considerations.

Secondly anchors aren't supposed to hold or set at 2-1 scope and many anchors being dragged at 2-1 would pull up their shank and hence their fluke tip and just drag along w hardly any resistance at all. How many anchors did'nt set in the above described manner .. and/or how many did? And what percentage of all the tests were done in this manner?

It seems very unscientific to make big changes in important steps of a scientific protocol in mid stream. One would think starting all over would be necessary to call it scientific or objective.

As to the breakouts like what happened w the Supreme could that be related to the roll bar clogging issue or theory?

Thanks for continuing to offer support for this thread.
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Old 10-07-2014, 12:04 PM   #760
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Originally Posted by manyboats View Post
Brian,
The mag articles were interesting in that given the same input such different opinions and text resulted.

By far IMO the first article was most overwhelmingly meaningful. And thus far I hadn't picked up on this part ... "After great debate and careful consideration to all anchors in the test, Hawley agreed to a change in the protocol in round five. The anchors were launched with an initial scope of 2:1 then pulled in 20 feet at 30 feet per minute until a load of 200-300 lbs. of torque indicated the anchor was set. From there the 8:1 scope was let out and the test resumed as normal. First up was the Fortress FX-37 at 45 degrees."

This seems really strange to me.

Firstly the most commonly held philosophy of setting anchors, even embraced by P Smith is to let out long scope and set the anchor. Then shorten up for swing and other considerations.

Secondly anchors aren't supposed to hold or set at 2-1 scope and many anchors being dragged at 2-1 would pull up their shank and hence their fluke tip and just drag along w hardly any resistance at all. How many anchors did'nt set in the above described manner .. and/or how many did? And what percentage of all the tests were done in this manner?

It seems very unscientific to make big changes in important steps of a scientific protocol in mid stream. One would think starting all over would be necessary to call it scientific or objective.

As to the breakouts like what happened w the Supreme could that be related to the roll bar clogging issue or theory?

Thanks for continuing to offer support for this thread.
Eric, thanks for your input. After every anchor had been tested 4x (48x in total - 10 competitive anchors + FX-37 tested @ both 32° & 45°) and near the end of the third day, we decided to follow and actually try our own advice in soft mud by setting not just the Fortress, but all anchors, using a shorter initial scope.

Since many of the anchors had setting issues during the course of the previous 48 pulls, we thought that we might learn something which we could then pass along to owners of these other anchors.

For example, a shorter scope with Rocna might have kept the shank more vertical and allow the fluke to dig in first and orient in the downward position.....but it didn't, nor did the shorter initial scope appear to help the other competitive anchors.

There were a total of 12 attempts with the initial shorter scope, one for each anchor, and it took us through until the end of the final day 4.


Regarding the clogging question and the Supreme, during the two pulls where it developed its highest tension, the Supreme broke free shortly afterwards and then it did not re-engage the bottom, but we saw the same thing occur with the non-roll bar Ultra, so I cannot conclude that the roll bar was to blame.
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