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Its interesting - other forum on arrival of a new member some optimist says something like 

'Welcome to the forum'

At least here you start as you mean to go on.

But - hey ho - my post count is increasing, even if my acceptance is going down.  But who worries about acceptance mavericks are never accepted - which is part why they are mavericks.  

 

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I think saw Q made the place a bit un-friendly. Who needs that?

When I started the anchor videos, it was just the underwater stuff and on-screen text.  Right away the accusations started flying that I was working for a particular anchor manufacturer.  Understandab

Posted Images

For nearly six years, this thread was wonderful. A really nice guy with genuine engineering talent has been doing serious, systematic testing of anchors.  Very open to feedback, and a lot of rigour applied to refine and evolve his methodologies.

This has rightly earned Steve great respect here on CA, but also from makers and vendors of anchor, who pay Steve the highest compliment: they send their anchors to Steve to test.  They wouldn't be doing that unless they had confidence that his testing process was rigorous, fair and honest.

Nobody else in the world is testing small boat anchors like this, with so many tests of so many anchors, and all videoed.  It's unique and wonderful, and Steve has put huge amount of time into it ... plus, AFAICS, a significant pile of coin into his new dedicated test boat.

But now, every time I see another post to this thread, it's turns out to be another of the hidden-because-I've-had-enough piles of nasty bile from someone who appears to be a shill.  The jewel of CA is being sprayed with dung :( 

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I wonder if this is Peter Smith, the self-anointed "original cruiser", and so-called inventor of the Rocna. Some might suggest cruising started some centuries prior ... but not Peter.  Recall all the poo-flinging when the new gen anchors came out in the early aughts. I guess it could also be John Knox but it has the Smith Arrogant ring to it. The man ... the legend:

Peter Smith

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Newish readers are unlikely to have read the older testing stuff. Here's the Gospel According to Smith https://www.petersmith.net.nz/boat-anchors/new-gen-boat-anchors-explained.php The other big clue is that Smith never has a good word about Mantus. 

I have to wonder if the recent barrage from "Saw Q" is a result of the poor showing on the Rocna in Steve's test.

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22 hours ago, Panope said:

A question for the engineers/metallurgists:

What happens to the properties/strength of HT Steel in the HAZ (heat affected zone of welding).

In some instances you can be susceptible to differential microstructure corrosion, but that is in uncoated materials. Galvanization should prevent any issues.

So long as the material is not cold when it is welded, you should be OK. If it was a worry, post welding normalization would eliminate the concern.

The good news about Chinese stainless is that you can drop a screw into a deep bilge and still get it back with a magnet.

The best pumpjacks in the world were long built by Lufkin Ind in Lufkin, Texas. Then GE bought them and moved all of the machinery and patterns to China to make a few extra bucks. This was under Immelt. I try to buy used USA pumpjacks. Properly maintained these will run 24/7 for over 60 years. 

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22 hours ago, Panope said:

A question for the engineers/metallurgists:

What happens to the properties/strength of HT Steel in the HAZ (heat affected zone of welding).

The weld generally is embrittled, but a lot depends on the quality of the weld.

In critical situations, heat treatment is applied to correct.

also, IIRC, they preheat the welded area…. There are various ways to account; it’s been awhile since I’ve had to think about it 

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4 hours ago, Blue Crab said:

I wonder if this is Peter Smith, the self-anointed "original cruiser", and so-called inventor of the Rocna. Some might suggest cruising started some centuries prior ... but not Peter.  Recall all the poo-flinging when the new gen anchors came out in the early aughts. I guess it could also be John Knox but it has the Smith Arrogant ring to it. The man ... the legend:

Peter Smith

Good working hypothesis, but I think it is the Viking guy. Same tone of snark as postings elsewhere (as the Viking guy) and Mantus is their obvious competition/ (cough) design inspiration. 

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13 minutes ago, Guvacine said:

Good working hypothesis, but I think it is the Viking guy. Same tone of snark as postings elsewhere (as the Viking guy) and Mantus is their obvious competition/ (cough) design inspiration. 

Whoever it is, he's an asshole.

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14 minutes ago, JRC026 said:

There is this Aussie twat on the English YBW Forum who has it in for anything Mantus, has literally thousands of anti Mantus postings and jumps on anyone whom dare defend that anchor in the slightest....and I think this is him finding his way over to SA.

Jonathan Neeves by name? 

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26 minutes ago, Guvacine said:

Good working hypothesis, but I think it is the Viking guy. Same tone of snark as postings elsewhere (as the Viking guy) and Mantus is their obvious competition/ (cough) design inspiration. 

If it's a Viking shill, then these antics are not just nasty, but self-defeating.  The Viking is coming out near the top in rankings by average, and in rankings by worst weak performance, it is the best all-round anchor.

If you are nasty person, then it makes sense to crap on the opposition when you are losing.  But not when you are winning.

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8 minutes ago, JRC026 said:

Dunno, but the twat wanks on about how he has written hundreds of articles for many sailing mags, Practical Sailor being one of them from memory....my memory is hazy though because after two or three back and forths I thought, nah, fuck this, I have better things to do with my life


Unfortunately looking at an anchor, whether its a Vulcan or a Viking does not actually tell you how it will work (though it might tell you why it might not work). It needs to be tested and used by people with a reputation for honesty and able to explain why it does (or does not) work. An example of this - look at the Fortress Chesapeake mud tests - Spade and Ultra look very similar - but behaved very differently. Mantus and Rocna look 'similar' but behaved differently. https://forums.ybw.com/index.php?threads/viking-anchors.524412/

Above is a decent read for real geeks only. Steve gets generally good reviews. 

.............................

I have to wonder about the bolt-together anchors. I don't think storability has as much to do with anything beyond shipping costs... now that's a real big deal. 

 

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53 minutes ago, Ishmael said:

Whoever it is, he's an asshole.

He’s Borat the Viking guy for sure. 

“In my country, we have big anchor roller and we say to let woman anchor boat is like to let a monkey fly a plane, very dangerous yes.”

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12 minutes ago, Blue Crab said:

I have to wonder about the bolt-together anchors. I don't think storability has as much to do with anything beyond shipping costs... now that's a real big deal. 

Storability is probably irrelevant for a main anchor which lives on the bow of a coastal cruiser ... but is still an issue if you want to take the anchor off the bow for a long passage, and store it somewhere low and central.  When cruising smaller boats (under 30foot), many cruisers never leave the anchor on the bow.

And storability is a big issue for secondary anchors, including storm anchors.  That is why Luke and Fortress emphasise the collapsibility of their anchors.

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1 hour ago, TwoLegged said:

Storability is probably irrelevant for a main anchor which lives on the bow of a coastal cruiser ... but is still an issue if you want to take the anchor off the bow for a long passage, and store it somewhere low and central.  When cruising smaller boats (under 30foot), many cruisers never leave the anchor on the bow.

And storability is a big issue for secondary anchors, including storm anchors.  That is why Luke and Fortress emphasise the collapsibility of their anchors.

Secondary for sure. I have too many Fortressi. And for sure off the bow in the ocean, I guess I just don't think I would go to the trouble to break the #1 down. Maybe going to Tahiti.

My main point was really economics. The bolt-togethers would save a wad of money on shipping. The Rocna has to cost way more to ship than a Mantus. Gotta be a big business decision.

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11 hours ago, Blue Crab said:

I wonder if this is Peter Smith, the self-anointed "original cruiser", and so-called inventor of the Rocna. Some might suggest cruising started some centuries prior ... but not Peter.  Recall all the poo-flinging when the new gen anchors came out in the early aughts. I guess it could also be John Knox but it has the Smith Arrogant ring to it. The man ... the legend:

Peter Smith

Sadly Professor Knox died about 12 months ago

Please check your data before casting aspersions (especially focussed at those unable to defend themselves - shame on you.

 

And read the provided link and check the graph - or do you like to be spoon fed or through a teat.

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4 minutes ago, Saw Q said:

Sadly Professor Knox died about 12 months ago

Please check your data before casting aspersions (especially focussed at those unable to defend themselves - shame on you. I'm on it. No aspersions check.

 

And read the provided link and check the graph - or do you like to be spoon fed or through a teat. No link but heall yaah on nipples.

 

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On 8/13/2021 at 7:55 PM, Saw Q said:

Aermet is hardly, very, high tensile.

Close to you, Woolongong, and made famous by Peter Smith you can source Bisplate 80, .........

 

Bisplate 80 is a very commonly available steel here. It's what the suppliers would recommend if you wanted a stronger steel to reduce weight, at a reasonable price.  But Bisplate 80 is only twice the strength of mild steel. It's used a lot for earthmoving and quarry equipment which is what actually made it well known, not Peter Smith who's a complete unknown to most designers using that steel.  

The lowest grade of Aermet (100) is well over twice the strength again of Bisplate 80 while the highest grade (340) is 3 times the strength of bisplate 80.

So why you think Aermet isn't high tensile?

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2 hours ago, MikeJohns said:

Bisplate 80 is a very commonly available steel here. It's what the suppliers would recommend if you wanted a stronger steel to reduce weight, at a reasonable price.  But Bisplate 80 is only twice the strength of mild steel. It's used a lot for earthmoving and quarry equipment which is what actually made it well known, not Peter Smith who's a complete unknown to most designers using that steel.  

The lowest grade of Aermet (100) is well over twice the strength again of Bisplate 80 while the highest grade (340) is 3 times the strength of bisplate 80.

So why you think Aermet isn't high tensile?

Because I read the wrong data :(

https://en.wikipedia.org/wiki/Aermet

I did not look at the various brackets - read the metric as imperial (or the other way round).

Apologies

And I kept your post count up :)

Bis 80 is also well known to yacht designers - it is used for the fin on performance yachts, like Wild Oats - which is how I know of it.  Peter Smith, I suspect son Craig, brought it to the attention of anchor geeks.

I don't know Aermet, obviously - can you weld, fold it and importantly galvanise it?

 

 

 

 

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And Mike,

 

It was a very stupid mistake the trouble with a big part of the world using Metric but a critical part of the world using Imperial

I did not fee l quite so ashamed at my error - as no-one else noticed either.  :)

Enjoy the few hours left in your weekend - we have another day off yet.  :)

 

 

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18 hours ago, Blue Crab said:

Newish readers are unlikely to have read the older testing stuff. Here's the Gospel According to Smith https://www.petersmith.net.nz/boat-anchors/new-gen-boat-anchors-explained.php The other big clue is that Smith never has a good word about Mantus. 

I have to wonder if the recent barrage from "Saw Q" is a result of the poor showing on the Rocna in Steve's test.

Not specifically focussed at you Blue Crab, I acknowledge you are a gentleman.

 

Instead of wondering who the messenger is - best shoot her (or him) then we don't need to think about the message. its buried.

No need to burn books, just don't read it.

Ignorance is bliss

 

How about a new strategy

Argue with the information, ignore the verbage.  Play the ball not the player - it might be more valuable, look at the 'engineering'

 

 

 

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2 minutes ago, random. said:

If you did not already know, iOS has nothing to do with the browser functionality.

Hover over the user avatar then select 'ignore'.

Thanks, can’t hover on an iPad or iPhone but I figured it out. I don’t use laptops or PCs anymore.

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3 minutes ago, loneshark64 said:

Thanks, can’t hover on an iPad or iPhone but I figured it out. I don’t use laptops or PCs anymore.

I see yr point LS but I wouldn't miss this. I'm an anchor nut. At one point I had nine of varying size and weights but not enough boat to carry them all. 3 years ago I bought a Rocna 10. It would stop my Cal 29 in sand and give you whiplash. Someone stole it. I was about to order a Mantus 2 for new boat ... and didn't pull the trigger for some reason.  

For info, I went thru the Viking order process yesterday. The V7 is 229US but the shipping adds 104US. For no good reason, I trust Ukrainian workmanship over Chinese plus I've seen a few broken welds.  

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I figured an anchor thread would go sideways, but not like this. 

I've never used the ignore button yet. I figure it's the internet. If I'm that invested, I have a more serious problem! 

Anyway, I'm interested in the results on the Bruce. It's always been a puzzle to me the discrepancy between the tested results and my real-world results. I figure one reason is that I mostly anchor in soft mud. 

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1 hour ago, loneshark64 said:

Very interested to hear how that goes. I may rethink. Please follow up.

I was just curious. Someone on another forum said shipping took a week. I haven't ordered yet but if I do I'll use PayPal. Maybe I won't lose out if it doesn't work out. 

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On 8/15/2021 at 10:24 AM, Elegua said:

... Anyway, I'm interested in the results on the Bruce. It's always been a puzzle to me the discrepancy between the tested results and my real-world results. I figure one reason is that I mostly anchor in soft mud. 

Testing things like corrosion and fuel stability required accelerating and exaggerating the conditions in order to make comparisons in  reasonable time period. We commonly add additional corrosive or oxidizing chemicals to speed things along, and we have to be very careful they don't cause corrosion modes that are completely unrealistic. More air (oxygen) is added, and even pure oxygen. Temperatures are increased. We then try to relate the test results to what we see in the field; sometimes they match, sometimes they do not.

Same with anchoring.  Nearly every testing protocol involves setting an anchor withing minutes, if not seconds. We see how an anchor behaves while it is moving, not actually set and soaked into the mud for even 15 minutes, and certainly not hours. Some keep gliding, some lock up. Holding can increases as much as 100% over a few hours of alternating rest and gentle nudging. Wiggle your feet into wet sand or mud. Some are more prone to liquefying the soil around them when twitched than others.

The bottom seems infinitely variable. I have returned to the same consistent fine sand area for testing, and even a change in season can change the results by 30%. Repeated test the same day normally vary by 25-50%. The notion that a difference in test results of 30% is significant is just not supportable.

I find anchor testing very intriguing. I also know from experience that the results never indicate anything more than trends. Some anchors are better at A, some better at B, and some properties we don't even test (hold after soaking--Knox is one of the few that talk about it, other than platform anchor makers).

Panope is doing a lot of good work, but like any testing, you have to think deeply about what it means in the real world. He has accurately documented the initial setting process under many conditions. Very, very cool. Great work. But lets look at things he is having trouble documenting. This is NOT a criticism. Few have done anything with these questions:

  • Hold after soaking periods. Think about walking about wet sand vs. wiggling your feet into it. I did a limited study of anchor holding capacity after soaking and cyclic loading, and found that it could increase anywhere from25-150%, depending on the bottom and test conditions. Platform and ship anchor manufactures have done similar testing, and their data fit the curve. This is VERY time consuming to test. Additionally, there was limited correlation between static holding and dynamic (quick holding) capacity. Translation; results can vary with how fast you pull and how long you wait between pulls, and it depends strongly on where you test.
  • Veering. How often do you veer an anchor at about 70% of it's holding capacity (in other words, when it is actually still microscopically moving)? Almost never. This results in false outcomes. For example, the Fortress rotates reasonably well in this test, but in practice, we know the Fortress almost never rotates at all. I don't think this test models any realistic condition. Darn. I like the test. I liked tests for fuel and coolants I developed that gave interesting results... that did not match the real world... so we abandoned the tests. It's tough, but if a test does not mimic reality, it's not a useful test. I suggest that a better test would be to set the anchor well, then rotate 90 degrees under light tension (maybe 10-20% of holding capacity), and then very slowly load to break out (5 minutes at least). I have done the test this way. The results are different. But this is more similar to a weather system passage... I think.
  • 180 test. I'm OK with this one. Tide reversals can be like that. Been there. But if conditions are such that your anchor is going to break out and have to reset, I'd use two anchors. I don't like the odds. enough cycles and the best anchor is going to catch a tin can or ball of weeds. Certainly only safe where maximum rode tension will be less than 10% of the holding capacity of the anchor in that bottom.

The key problem, I think, is that we know very little about how anchors actually fail in the real world. No one is diving or filming the anchor during that once-every-500 anchoring episodes when it dragged. We know little about the break-out behavior of anchors that have been well-set for hours. I've only seen a few, when I was diving on undersized anchors in testing. Some were on rock (either lift of veer). Some in sand (deep set, pulled out fast with no chance of reset). One was mud (fouled in stick, not actually set but seemed to be, stick broke). But they were small anchors (2-pounds for a 34-foot cat, with the boat anchored using 35-pound backup with some slack).

Honestly, I think picking a "Best" from a group of very good anchors is probably tough. I'm more interested in trends.

  • Fortress struggles with with many bottoms, can't relied upon to rotate or reset, but holds tons in good bottoms, specifically mud. If it isn't holding tons, the bottom isn't mud or you are setting it wrong. I've seen as much as 600:1 holding, and never less than 100:1 in very soft mud with a soak period.
  • Bruce struggles with weed and has less hold per pound than most, but if large enough it always generates some hold. Big Bruce owners are normally happy--this trend is more consistent than other types.
  • Mantus sets shallow in sand and deep in mud. Weird, and I suspect I know why, but leaving that alone.
  • Scoops tend to clog but do well until they do.
  • The Delta stinks in soft mud and certain hard bottoms, but does better in medium bottoms.
  • Some anchors give very different results/rankings from one test program to another. That just goes to show it is complicated. I don't understand it!

 

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Great Post.  Agree with all.

My thoughts in red:

46 minutes ago, thinwater said:

Testing things like corrosion and fuel stability required accelerating and exaggerating the conditions in order to make comparisons in  reasonable time period. We commonly add additional corrosive or oxidizing chemicals to speed things along, and we have to be very careful they don't cause corrosion modes that are completely unrealistic. More air (oxygen) is added, and even pure oxygen. Temperatures are increased. We then try to relate the test results to what we see in the field; sometimes they match, sometimes they do not.

Same with anchoring.  Nearly every testing protocol involves setting an anchor withing minutes, if not seconds. I probably put more value in the "emergency stop" function of anchors than most.  That was certainly my primary thoughts when I began all this testing madness. We see how an anchor behaves while it is moving, not actually set and soaked into the mud for even 15 minutes, and certainly not hours. Some keep gliding, some lock up. Holding can increases as much as 100% over a few hours of alternating rest and gentle nudging. Wiggle your feet into wet sand or mud. Some are more prone to liquefying the soil around them when twitched than others.

The bottom seems infinitely variable. I have returned to the same consistent fine sand area for testing, and even a change in season can change the results by 30%. Repeated test the same day normally vary by 25-50%. The notion that a difference in test results of 30% is significant is just not supportable.

I find anchor testing very intriguing. I also know from experience that the results never indicate anything more than trends. Some anchors are better at A, some better at B, and some properties we don't even test (hold after soaking--Knox is one of the few that talk about it, other than platform anchor makers).

Panope is doing a lot of good work, but like any testing, you have to think deeply about what it means in the real world. He has accurately documented the initial setting process under many conditions. Very, very cool. Great work. But lets look at things he is having trouble documenting. This is NOT a criticism. Few have done anything with these questions:

  • Hold after soaking periods. Think about walking about wet sand vs. wiggling your feet into it. I did a limited study of anchor holding capacity after soaking and cyclic loading, and found that it could increase anywhere from25-150%, depending on the bottom and test conditions. Platform and ship anchor manufactures have done similar testing, and their data fit the curve. This is VERY time consuming to test. Additionally, there was limited correlation between static holding and dynamic (quick holding) capacity. Translation; results can vary with how fast you pull and how long you wait between pulls, and it depends strongly on where you test.

I suspect that some of the seabeds where I test are less affected by soaking than many others.  For example, my "Cobblestone" seabed most certainly has zero soaking affect.  My "clean sand" site probably has very little affect (have not tested).  I can easily see how my mud sites would be affected, although I could not detect any difference between 0 and 10 minutes.  Need to soak longer.

The "wiggling" however, could affect ANY substrate (except bed rock and boulders, perhaps).  I have yet to dream up a repeatable "wiggling" test, but I am working on it.   

That said, it would be a somewhat common scenario for an anchor to be set in calm conditions and lie for hours or days without ANY tension (especially if lots of chain is used.  Then, a strong wind arrives suddenly (TS) and the anchor is being challenged in a way that is not too different from the "zero soak time" testing.

  • Veering. How often do you veer an anchor at about 70% of it's holding capacity (in other words, when it is actually still microscopically moving)? Almost never. This results in false outcomes. For example, the Fortress rotates reasonably well in this test, but in practice, we know the Fortress almost never rotates at all. I don't think this test models any realistic condition. Darn. I like the test. I liked tests for fuel and coolants I developed that gave interesting results... that did not match the real world... so we abandoned the tests. It's tough, but if a test does not mimic reality, it's not a useful test. I suggest that a better test would be to set the anchor well, then rotate 90 degrees under light tension (maybe 10-20% of holding capacity), and then very slowly load to break out (5 minutes at least). I have done the test this way. The results are different. But this is more similar to a weather system passage... I think.

Agree, my current veer test is abstract.  On my very long list of "future" tests is a protocol just like the 90 degree test that you suggested.

  • 180 test. I'm OK with this one. Tide reversals can be like that. Been there. But if conditions are such that your anchor is going to break out and have to reset, I'd use two anchors. I don't like the odds. enough cycles and the best anchor is going to catch a tin can or ball of weeds. Certainly only safe where maximum rode tension will be less than 10% of the holding capacity of the anchor in that bottom.

The key problem, I think, is that we know very little about how anchors actually fail in the real world. No one is diving or filming the anchor during that once-every-500 anchoring episodes when it dragged. We know little about the break-out behavior of anchors that have been well-set for hours. I've only seen a few, when I was diving on undersized anchors in testing. Some were on rock (either lift of veer). Some in sand (deep set, pulled out fast with no chance of reset). One was mud (fouled in stick, not actually set but seemed to be, stick broke). But they were small anchors (2-pounds for a 34-foot cat, with the boat anchored using 35-pound backup with some slack).

Honestly, I think picking a "Best" from a group of very good anchors is probably tough. I'm more interested in trends.

Agree. finding the "Best" in ultimate terms will never happen.  "Best" at particular things is probably findable.

  • Fortress struggles with with many bottoms, can't relied upon to rotate or reset, but holds tons in good bottoms, specifically mud. If it isn't holding tons, the bottom isn't mud or you are setting it wrong. I've seen as much as 600:1 holding, and never less than 100:1 in very soft mud with a soak period.
  • Bruce struggles with weed and has less hold per pound than most, but if large enough it always generates some hold. Big Bruce owners are normally happy--this trend is more consistent than other types.
  • Mantus sets shallow in sand and deep in mud. Weird, and I suspect I know why, but leaving that alone.
  • Scoops tend to clog but do well until they do.  
  • Concaves tend to be less stable in "roll" but do well until they do.
  • Rollbars tend to have less holding in heavy sticky mud, and more holding in soft mud.
  • The Delta stinks in soft mud and certain hard bottoms, but does better in medium bottoms.
  • Some anchors give very different results/rankings from one test program to another. That just goes to show it is complicated. I don't understand it Me neither.  If I were to collect, say, 10 times more data than I currently have (with new seabeds and protocols).  Maybe we will get somewhere.

 

 

Although I appreciate their good wishes, I always cringe when someone unequivocally states that my testing is the holy grail.  I would certainly like it to be, but it is not there.......

Yet.

Steve

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......adding to the thoughts above:

After completing the 180 degree veer in SOFT MUD, the anchors tend to have significantly GREATER holding power than when pulled straight only.  This veer is probably acting like a long, wiggling, soak.  

Conversely-

After completing the 180 degree veer in the SANDY MUD, the anchors tend to have significantly LESS holding than when pulled straight only.  This may indicate that for the Sandy Mud, long soaking/wiggling may have not to great effect.

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Just think back--It was ERIC THE RED (one of the original cruising sailors), I believe a Viking, who said:

 

'There is no such thing as bad weather just the wrong choice of anchor'

 

Or words to that effect - and that was 1,000 years ago.

 

Yet we still expect one single anchor design to be perfect.

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2 hours ago, Ishmael said:

Or at least mock them.

"So many fuckwits, so little time"

 

Are you really saying that you think this sort of language, and the quote is not alone, is acceptable and does not ruin threads.

 

You will be pleased to know I find it embarrassing, unnecessary and probably a bad sign of character.  But if you think it raises the tone - who am I to complain.  But really - you reap what you sow.  Have threads without the need to use blasphemy and you might get threads with better content.

 

You set the standards - I just followed.

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2 hours ago, Ishmael said:

Blasphemy? Who are you, the Taliban?

I did not raise this.

Not at all, though they do seem to be telling some of us - how it is, which is only what the the British discovered in days of Empire, the Russians more recently and now - the allies.

My point was there is no suggestion I have seen that blasphemy and technical excellence are good bedfellows.  I stand to be corrected.

 

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On 8/13/2021 at 11:21 AM, Panope said:

A question for the engineers/metallurgists:

What happens to the properties/strength of HT Steel in the HAZ (heat affected zone of welding).

Yes indeed,  I always wondered about this one.  "It's hardened and tempered steel!!"  Yeah, that has been heated to bright red by welding and now is pretty much annealed in spots.  Unless the whole item is heat treated after construction I can't see how this doesn't create soft spots.  I also don't know if some welding technologies are so fast and tightly focused that there is little or no surrounding softening of the steel.

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Panope, re. very soft mud and soaking.

Yes, some bottoms it makes close to no difference. Cobbles and rock, certainly. Clean sand, mostly.

But at least on the Chesapeake soft mud I tested, So long as there was the slightest tugging, even 5 knots, and some quiet periods, the anchor seems to be pulled down through the fluff, wiggled into better mud just a little, and then that mud gets to consolidate around the anchor. Then, when the load comes on, it can dig far more steeply than the normal long setting plow that is required in unconsolidated super soft mud.

This graph relates to a specific test protecole, that includes both quite periods and loading periods, with considerable rests between them. Sometimes we relied on variable winds, other times winching every 15 minutes. The results showed the same trend.  Not all of the data was mine, either. Yes, the improvement in sand was more than twice that in fine (not coral sand--different animal with different flow properties) sand, but there was still a clear trend.

holding capacity vs. soak time

Anchor Soaking Article

What I did not study enough and still wonder about, is how anchors that have been set deep and slow in mud behave when the wind rotates. Is the deep set and soil consolidation advantage lost, or do they still benefit from being deeper to start with? I'm guessing some of both, and it probably depends on the speed of the veer.

And how fast is the veer in a thunderstorm? Faster than a weather front, but there are nearly always some moderate gusts from the new direction before the dangerous blasts hit. And in both cases, the chain needs to pull through the mud. Of course, this depends a great deal on scope and how much chain is lying on the bottom.

Complicated. If I really expect a 120 rotation and a blast, when anchored on very soft mud, I will probably set a second anchor (Fortress) broad of the shift, so that the rodes end up in a V. That does not move and that does not require the anchors to rotate, preserving the deep set. Look at those holding capacities. 500 pounds from a 45-pound anchor. Some areas are worse, only a few hundred pounds. The peak rode tension on any boat that would carry a 45-pound anchor is more than that at 60 knots, more like can easily be greater than that, more like 1500-2000 pounds in the sort of storm that fills the cockpit with hailstones (I enjoyed one of those a week ago--glad I was anchored in good sand). Which is why during that sort of storm, in most Chesapeake creeks, if there are more than 6 boats, someone drags.

 

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18 hours ago, low bum said:

Yes indeed,  I always wondered about this one.  "It's hardened and tempered steel!!"  Yeah, that has been heated to bright red by welding and now is pretty much annealed in spots.  Unless the whole item is heat treated after construction I can't see how this doesn't create soft spots.  I also don't know if some welding technologies are so fast and tightly focused that there is little or no surrounding softening of the steel.

No there's no quick low heat techniques, everything has to be fused together so there's always a HAZ.  Welding thinner plate and it's recommended to design for low strength consumables ( weld filler) to avoid cracking.  But it can be done full strength with the right techniques and post treatment but it's specialist and expensive.

For thick sections the root runs are done in lower strength and temper beads can be layered over the root welds. But again it's best to design for all low strength consumables. There's quite a lot to this. There are comprehensive engineers design guides for using decent HT steel plate such as ASTM A514/T-1.

 

 

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20 hours ago, robtoujours said:

Neeves should fuck off. He probably gets some weird sexual thrill from posting. On the ignore list now, suggest all do the same and don’t respond to him

You reap what you sow.

 

You accused me of trolling (a newbie you did not know - what a welcome) - when all that was being done was comparing 2 similar anchors Viking and Mantus.  You completely ignored the evidence and now are suggesting I'm someone else.  Bizarre.  Strangely Thinwater has said the same thing - Mantus sets shallow.  So ignore me as you are apparently all doing, and check Thin's comment.  It is important because if the ultimate hold is lower than YOU obviously anticipate and if you think and depend on Mantus having a similar hold to a Rocna or Supreme - you might be, very, disappointed - so be wary, not complacent- embrace the data.  Anchoring is about safety - they are safety devices - you want something you can rely on - in the extreme.

What might merit some consideration - anchors with measured high hold are largely high up Steve's spreadsheet.  So anchors with SHHP ratings do well - whatever.  So if you want a simple answer - opt for a Classification Society certificated SHHP anchor, Spade, Excel, Supreme, Rocna, Fortress as a first filter and then look at Steve's results.

 

 

 

 

 

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I commented that Mantus seems to set shallow in sand and deeper in mud, compared to other anchors. I did NOT comment on holding capacity and I would rather it not be implied that I did. What I was pointing out was the interesting curiosity that Mantus repeatedly does quite well in very soft bottoms, which seems in contrast with the shallow angle and generally shallow setting behavior, but there it is. It also did well in soft mud years earlier in the Fortress sponsored soft mud tests in Maryland. I've noticed that the large hoop makes it resistant to fouling with soft mud trash. It puts up good numbers we don't understand looking at the design... but we don't need to. The POINT I was making is that an anchor is the sum of its parts and they don't always act as you would expect.  I don't know about you guys, but anchors constantly surprise me with results I can't explain, but accept if they are repeated.

The main thing I look for in anchor test results is repeatability. Look at Panope's results. Look at the Fortress test. I like the anchors that can do something good, time after time. Is there a "best" anchor? I doubt it. There are clearly a handful of very good anchors.

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Re: Mantus holding:

I have completed winch testing the 20 lb. (range) anchors in the Sandy Mud and have recalculated my holding/resistance data based on an average of many sets with prop thrust AND the new winch data.  Some new and very interesting findings will be presented in my next video.

Also, I am shifting from ranking the anchors "head to head", to a ranking based on Holding/Anchor Weight.

Here is a sneak peak at some new data:

SOFT MUD HOLDING/ANCHOR WEIGHT 5:1 SCOPE, 80' CHAIN (DEPTH 25'):

  • 17lb Mantus M1    -  37 (rollbar bends without strap)
  • 21lb Viking            -  32
  • 22lb Rocna           -  27
  • 21lb Vulcan           -  22
  • 17lb Mantus M2   -  21
  • 26lb CQR              -20
  • 21lb Excel              -20
  • 21lb Spade S60    -19
  • 22lb Quickset        -14
  • 17lb Excel               -11

SANDY MUD RESISTANCE/ANCHOR WEIGHT 5:1 SCOPE, 12' CHAIN (DEPTH 25'):

  • 21lb Spade S60     -75
  • 17lb Mantus M2     -67
  • 21lb Vulcan            -67
  • 26lb CQR               -61
  • 22lb Quickset        -55
  • 21lb Excel              -52
  • 21lb Viking             -52
  • 17lb Excel              -47
  • 17lb Mantus M1     -43
  • 22lb Rocna            -27

Mantus M1 and Viking dominate the SOFT MUD (Mantus better)

Mantus M1 and Viking well down on the SANDY MUD list (Viking better)

Steve

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1 hour ago, thinwater said:

I commented that Mantus seems to set shallow in sand and deeper in mud, compared to other anchors. I did NOT comment on holding capacity and I would rather it not be implied that I did. What I was pointing out was the interesting curiosity that Mantus repeatedly does quite well in very soft bottoms, which seems in contrast with the shallow angle and generally shallow setting behavior, but there it is. It also did well in soft mud years earlier in the Fortress sponsored soft mud tests in Maryland. I've noticed that the large hoop makes it resistant to fouling with soft mud trash. It puts up good numbers we don't understand looking at the design... but we don't need to. The POINT I was making is that an anchor is the sum of its parts and they don't always act as you would expect.  I don't know about you guys, but anchors constantly surprise me with results I can't explain, but accept if they are repeated.

The main thing I look for in anchor test results is repeatability. Look at Panope's results. Look at the Fortress test. I like the anchors that can do something good, time after time. Is there a "best" anchor? I doubt it. There are clearly a handful of very good anchors.

As you said earlier we get into the design and analysis and shortcomings / limitation of studies in a complex scenario. 

But it's indicative and these tests are appreciated.

I worked a lot with commercial boats, it's interesting asking the skippers of coastal fishermen who anchor out a lot what they think of anchors. We regulate the min size of their ground tackle and require proof tested certified anchors but they always exceed the requirement. Weight is popular. 

 

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Test repeatability:

I am finding that the  PEAK resistance numbers that I am collecting with the WINCH are quite similar to the RELEASE numbers that I have collected with PROP THRUST.

----------------------------

From the testimony given by Thinwater concerning the variability that he has found in seabeds, I have to believe that my test sites give much more repeatable results.  I have two possible explanations:

  • Other than weeds and shells, my seabeds are relatively free of "junk".
  • There are no rivers anywhere near my test sites.  The assumption is that a river may eject different material by season.
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Fluke Angle (Chain attach location):

My assumption is that this is an unknowable value. 

A useful number might be the angle between the fluke "plane" (easy to define on flat plate flukes, impossible on curved/convex flukes) and an imaginary line between the CHAIN ATTACH HOLE and the CENTER OF PRESSURE/RESISTENCE (extremely difficult to predict) of the entire anchor.

Ok, maybe if a fluke was completely symmetrical, like a disk, and there was nothing else sticking out like rollbars and upturned palms, we could predict where the center of pressure/resistance lies.  But, even a basic "triangle" shaped fluke could have a center of pressure very different from it's geometric center.  Has anyone forced an asymmetrical shape through a media (like a seabed) at an oblique angle, and measured the center of pressure/resistance?

Also, a longer shank will probably have the affect of making the fluke angle less important.  Imagine a shank that was, say, 100 feet long.  No amount of differential pressure on a (normal sized) fluke will have a meaningful affect on the "pitch" attitude of the anchor.  Now imagine a shank that is only 1 inch long.  Even the slightest bit of differential pressure on a (normal sized) fluke will cause the anchor to "pitch" greatly.

A calculation based on an "educated guess" might be a reasonable starting point for an anchor designer, but the final/best chain attach location is almost certainly found by trial and error.  

Now that I mention it, the whole idea of a "best chain attach location" is probably a moving target depending on seabed type and possibly how "fat" the rode is (fat rodes do not penetrate as easily). 

Steve

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2 hours ago, Panope said:

Fluke Angle (Chain attach location):

My assumption is that this is an unknowable value. 

A useful number might be the angle between the fluke "plane" (easy to define on flat plate flukes, impossible on curved/convex flukes) and an imaginary line between the CHAIN ATTACH HOLE and the CENTER OF PRESSURE/RESISTENCE (extremely difficult to predict) of the entire anchor.

Ok, maybe if a fluke was completely symmetrical, like a disk, and there was nothing else sticking out like rollbars and upturned palms, we could predict where the center of pressure/resistance lies.  But, even a basic "triangle" shaped fluke could have a center of pressure very different from it's geometric center.  Has anyone forced an asymmetrical shape through a media (like a seabed) at an oblique angle, and measured the center of pressure/resistance?

Also, a longer shank will probably have the affect of making the fluke angle less important.  Imagine a shank that was, say, 100 feet long.  No amount of differential pressure on a (normal sized) fluke will have a meaningful affect on the "pitch" attitude of the anchor.  Now imagine a shank that is only 1 inch long.  Even the slightest bit of differential pressure on a (normal sized) fluke will cause the anchor to "pitch" greatly.

A calculation based on an "educated guess" might be a reasonable starting point for an anchor designer, but the final/best chain attach location is almost certainly found by trial and error.  

Now that I mention it, the whole idea of a "best chain attach location" is probably a moving target depending on seabed type and possibly how "fat" the rode is (fat rodes do not penetrate as easily). 

Steve

if you really want to find the center of pressure/resistance or what we call it "center of gravity" and as an anchor designer you should, you need to take the fluke in question submerge it in a clear water tank with two ropes connected to its sides in such a way that you can change the location of the ropes on the toe-heel axel and start lifting it up if the fluke leans forward, move the ropes to forward and if it leans back while lifting it, adjust again accordingly when the fluke is lifted evenly the location of the rope at the wings axel is your center of gravity.

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For those of you who have not put me on the ignore list and have lived in hope for more beneficial data - here is the payback.  For those who put me on the ignore list - ignorance is bliss.

Now this will allow you to fill in some background work.

Steve and Thin will already have devoured this research, as will Greg as it was conducted in Houston.

Kim, the author, simply took all those characteristics that we consider important in an anchor, fluke area, shank length, shape of shank, shank/fluke location etc etc and etc and ran tests on virtually everyone one of them.   He even ran tests on fluke/seabed angle (producing results independent of the graphs posted earlier).   His co-authors are legends in anchor research, so anything they have written merits attention and Kim adds to the compendium of knowledge by a decent reference list.  The reference list alone will keep you busy for weeks.  Much of the work, I suspect, is not totally original Kim might simple have repeated some work - but he has beneficially compiled it into one body of research.  The work focusses on 'fluke' anchors - those without ballast.

Coincidentally Kim cover some of the topics that have been debated over the last few days.

I will not direct you to the relevant pages, better you read and devour without anyone leading you by the nose and offer opportunity  suggestions of bias, trolling etc.  Maybe Thin and Steve will offer you short cuts.

Enjoy

https://core.ac.uk/download/pdf/147126425.pdf

Have a great and educational day.

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10 hours ago, thinwater said:

I commented that Mantus seems to set shallow in sand and deeper in mud, compared to other anchors. I did NOT comment on holding capacity and I would rather it not be implied that I did.

You have said Mantus sets shallow in sand.  Can you explain how it could set shallow and have the same hold as a similarly sized anchor that sets deeply?

You have never mentioned the hold of a Mantus - there was no suggestion you had made such a comment.

In the absence of some qualification to your comment there does seem a reluctance to address, or comment on, the obvious.

 

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10 hours ago, Panope said:

Test repeatability:

I am finding that the  PEAK resistance numbers that I am collecting with the WINCH are quite similar to the RELEASE numbers that I have collected with PROP THRUST.

----------------------------

From the testimony given by Thinwater concerning the variability that he has found in seabeds, I have to believe that my test sites give much more repeatable results.  I have two possible explanations:

  • Other than weeds and shells, my seabeds are relatively free of "junk".
  • There are no rivers anywhere near my test sites.  The assumption is that a river may eject different material by season.

I used some very consistent areas for testing as well. As you say, not near rivers etc.

I don't think it's only junk in the tree limb or heavy sediment sense. One of the areas is very find sand, like perfect ocean beach sand, very clean, but finer. But there is still an organic component; some algae or bacteria or something you can't even see, and it changes the shear strength in some minor way with the seasons. Or maybe storms stir up the layers and it's slightly different in strength for a while. Very odd. However, the variation is only about 25%, no matter how many times you test. Never a "fluke" result. On a given day, +/- 5-10%.

But the truth is that I am more interested in how anchors deal with junk and irregularities, because I believe that is the cause of most failures. That and yawing. In a good bottom, without irregularities, any good anchor of the correct size holds.

Enough testing enough places gives you a feel for which anchors are more consistent. Thus, it is important to record the setting failures and odd results as well as average and peaks. They are part of the data. Perhaps the anchor the is darn good 5 times out of 5 is better than the anchor that is perfect 4 times and fails the fifth.

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5 hours ago, Panope said:

Izi, how do you know that the center of pressure/resistance in a liquid will be the same as a semi solid?

Semi solid will not have turbulence, among other differences.

I think we have also noticed that the density and shear strength does not always increase with depth in the theoretical manner. Often, there is a loose, mixed layer near the surface, and then density increases rather suddenly. under it. Cobbles are one example, but any area exposed to wave or tide action can layer like this. It can be a very challenging situation that some anchors don't like.

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5 hours ago, Panope said:

Izi, how do you know that the center of pressure/resistance in a liquid will be the same as a semi solid?

Semi solid will not have turbulence, among other differences.

Steve, any resisting material will do, from water to jello (even better), indeed there might be some influence from friction with different viscosity materials but the difference is minor.

Once you have found the center of gravity you can determine the fluke/shackle hole angle you want to achieve. 

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2 hours ago, Saw Q said:

You have said Mantus sets shallow in sand.  Can you explain how it could set shallow and have the same hold as a similarly sized anchor that sets deeply?

You have never mentioned the hold of a Mantus - there was no suggestion you had made such a comment.

In the absence of some qualification to your comment there does seem a reluctance to address, or comment on, the obvious.

 

See the Panope data several posts above. It is generally in line with what I expected. And it's' better than theorizing.

As Panope has said, "best" is hard to define and perhaps depends on where you anchor.  I'm not interested in joining that fight.

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3 hours ago, thinwater said:

........But there is still an organic component; some algae or bacteria or something you can't even see, and it changes the shear strength in some minor way with the seasons......

Interesting.

I have not noticed this phenomena.  Perhaps our stable water temperatures (they vary only a few degrees (F) by season) are a factor. 

The exception is the "Soft Mud" site, as it will vary about 15 degrees (F) by season, at the surface.  Not sure about temps at the 25-30 foot depth.  Probably more stable.

How much seasonal variation in water temperature do you have?

Steve

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In spite of my desperation to test in seabeds that (apparently) do not exist in my area (hard sand, etc), I feel extremely fortunate to have found 4, very different seabeds with high repeatability - all within a 30 minute motor boat ride of each other.

-----------------------------

I recently reviewed the "Puget Sound Anchor Test" of 1995.  A seabed containing "hard glacial clay" was mentioned at a geographical site about an hours drive (by car) from my location. 

I contacted one of the participants/authors of the test to get more specific details.  Sadly, his recollection is imprecise.  

I hope to soon visit this area with an anchor and a camera.  Might get lucky and find another, distinct seabed type.

Steve 

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21 minutes ago, Panope said:

Interesting.

I have not noticed this phenomena.  Perhaps our stable water temperatures (they vary only a few degrees (F) by season) are a factor. 

The exception is the "Soft Mud" site, as it will vary about 15 degrees (F) by season, at the surface.  Not sure about temps at the 25-30 foot depth.  Probably more stable.

How much seasonal variation in water temperature do you have?

Steve

The temperature of the water at this beach ranges from 90F to 32F. Seriously. Like a bathtub in the summer, ice floes in the winter.

The soft mud areas less so. The water is deeper/cooler in the summer, and the anchor is deeper under ground (more stable). But the biologic component is larger. But those areas are more variable for many reasons. The fine sand is a much more consistent media.

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25 minutes ago, Panope said:

I recently reviewed the "Puget Sound Anchor Test" of 1995.  A seabed containing "hard glacial clay" was mentioned at a geographical site about an hours drive (by car) from my location. 

Probably referring to the old Walmart parking lot in Port Angeles. Anchoring attempts on the asphalt will closely mimic Fla Keys hard bottom.

The former Port Angeles Walmart store in east Port Angeles. — Keith Thorpe/Peninsula Daily News

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4 hours ago, thinwater said:

Perhaps the anchor the is darn good 5 times out of 5 is better than the anchor that is perfect 4 times and fails the fifth.

That is a similar logic to @estarzinger's preference for the anchor whose worst performance is better than the worst performance of others.  It seems to me to be good logic.

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2 hours ago, TwoLegged said:

That is a similar logic to @estarzinger's preference for the anchor whose worst performance is better than the worst performance of others.  It seems to me to be good logic.

Climbing gear is rated by 6 sigma minimum break strength, not average break strength.

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Anecdotal Data: A Dragging Database

Scientific testing investigates fundamental principles. You might build a very simple anchor, like a Buegel, and test it in a prepared sand bed. You might vary the length of the shank or the angle it makes, but not the shape or material, because you want to change only one variable at a time. The results might help you understand what is going on, but they would not predict the behavior of a real anchor in real mud. Eventually a mathematical model is built, based on the simple anchor, which is then used to predict the behavior of that anchor in other soils, for example. If the model is good, with the use of fudge factors, it might be extended to real anchors, merging into engineering testing. We won't get that far, but I'm sure the platform anchor makers have such prediction software for their anchors; they plug in soil test data and hope to predict which anchor will work at a given site. Some testing of rigging geometries, yawing effects, and time factors fall in "scientific" catagory.  Some snubber and bridle testing. The goal is to understand what is happening, not to test real equipment.

Engineering testing evaluates real equipment. This is what Panope and most testers do. While you may consider fundamental principles when trying to understand the data, and you should compare your results to anecdotal observations, the focus is on what the REAL ANCHOR does in REAL SOIL. Not why. You can't look at Panope's data and tell why something is true, and you really should not try to. If that is your interest, go to scientific testing, build a model, and have at it. Testing riding sails is like this. Or testing drogues.

Anecdotal reports define the problem. The problem is they are scattered and usually the exact circumstances are not know. There are no controls and they weren't collecting data on all the variables. But it is real and it is where the rubber meets the road. "My anchor dragged, and this is what I know about it." But it is neither engineering or science.

The other problem with testing and comments from the peanut gallery, is that each of has our own experience. Type of boat. Weather. Bottoms. Anchor types. Deep or shallow. Crowded or remote. We can try to look outside our box (forums are good for this), but we start with what we know.

-----

I'd love to see a "Dragging Anchor Database."  A form where you fill in some basic information, and then a very short narrative:

  • Boat type and size.
  • Wind and wave exposure. Tide.
  • Depth, scope, and rode type. Snubber length and diameter.
  • Anchor type and size.
  • Bottom type. This will probably require perhaps a dozen options to chose from.sand vs. mud. Hard vs. soft. Clean vs. shells and trash. Weeds.
  • Frequency. In other words, have you used this anchor 3 times or 3000 times.
  • Yawing and surging. How was the boat moving? Bridle, riding sail, or other?
  • Setting method and how long had you been anchored.
  • Other stuff I've missed.
  • Narrative.

If the table requested enough detail, I think it could be useful. For example, I would make perhaps 4 real life entries. Two relate to Danforth (good sand, light set, and a direction change in both cases), and two relate to Delta anchors in very soft mud. I've dragged anchors many, many times in testing, when I would intentionally use an undersize anchor in moderate conditions to simulate storm behavior, but they don't count in this sense.

This is a trick process. Example. On another forum a poster said his anchor was prone to fouling with the chain if the boat did 360s with the tide. He had a picture of the chain fouled around the anchor while raising. But then he mentioned that the anchor was hard to break out, and they dumped the chain twice in the effort. Did the chain wrap during the tide swings or when they dumped the chain on the anchor and horsed around with it? I don't know.

I think this would help Panope relate his results to the real world. I think they will show similar trends, but this could be an interesting confirmation. Some of the anchors are so new we just won't have anecdotal information for (Viking and Epsilon). The measure of a good test is whether it mirrors reality.

 

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I wonder if we need a standard way of describing "soft" vs. "firm."

I read somewhere that the original basis used in charts followed an old time Navy practice. I tried it a few times and realized I was really only testing "dense sand" and "very soft mud." There is middle ground, of course, but I was trying to limit variables.

Using a blunt stake (dimensions not known) and a hammer (not known):

·         Very dense sand: more than 50 blows/foot.

·         Sand: 25-50 blows/foot.

·         Hard clay: more than 16 blows/foot.

·         Consolidated mud/clay: 4-16 blows/foot.

·         Soft mud: 2 blows/foot.

·         Very soft mud/silt: you don't need the hammer to go a foot.

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7 hours ago, thinwater said:

Anecdotal Data: A Dragging Database

Scientific testing investigates fundamental principles. You might build a very simple anchor, like a Buegel, and test it in a prepared sand bed. You might vary the length of the shank or the angle it makes, but not the shape or material, because you want to change only one variable at a time. The results might help you understand what is going on, but they would not predict the behavior of a real anchor in real mud. Eventually a mathematical model is built, based on the simple anchor, which is then used to predict the behavior of that anchor in other soils, for example. If the model is good, with the use of fudge factors, it might be extended to real anchors, merging into engineering testing. We won't get that far, but I'm sure the platform anchor makers have such prediction software for their anchors; they plug in soil test data and hope to predict which anchor will work at a given site. Some testing of rigging geometries, yawing effects, and time factors fall in "scientific" catagory.  Some snubber and bridle testing. The goal is to understand what is happening, not to test real equipment.

Engineering testing evaluates real equipment. This is what Panope and most testers do. While you may consider fundamental principles when trying to understand the data, and you should compare your results to anecdotal observations, the focus is on what the REAL ANCHOR does in REAL SOIL. Not why. You can't look at Panope's data and tell why something is true, and you really should not try to. If that is your interest, go to scientific testing, build a model, and have at it. Testing riding sails is like this. Or testing drogues.

Anecdotal reports define the problem. The problem is they are scattered and usually the exact circumstances are not know. There are no controls and they weren't collecting data on all the variables. But it is real and it is where the rubber meets the road. "My anchor dragged, and this is what I know about it." But it is neither engineering or science.

The other problem with testing and comments from the peanut gallery, is that each of has our own experience. Type of boat. Weather. Bottoms. Anchor types. Deep or shallow. Crowded or remote. We can try to look outside our box (forums are good for this), but we start with what we know.

-----

I'd love to see a "Dragging Anchor Database."  A form where you fill in some basic information, and then a very short narrative:

  • Boat type and size.
  • Wind and wave exposure. Tide.
  • Depth, scope, and rode type. Snubber length and diameter.
  • Anchor type and size.
  • Bottom type. This will probably require perhaps a dozen options to chose from.sand vs. mud. Hard vs. soft. Clean vs. shells and trash. Weeds.
  • Frequency. In other words, have you used this anchor 3 times or 3000 times.
  • Yawing and surging. How was the boat moving? Bridle, riding sail, or other?
  • Setting method and how long had you been anchored.
  • Other stuff I've missed.
  • Narrative.

If the table requested enough detail, I think it could be useful. For example, I would make perhaps 4 real life entries. Two relate to Danforth (good sand, light set, and a direction change in both cases), and two relate to Delta anchors in very soft mud. I've dragged anchors many, many times in testing, when I would intentionally use an undersize anchor in moderate conditions to simulate storm behavior, but they don't count in this sense.

This is a trick process. Example. On another forum a poster said his anchor was prone to fouling with the chain if the boat did 360s with the tide. He had a picture of the chain fouled around the anchor while raising. But then he mentioned that the anchor was hard to break out, and they dumped the chain twice in the effort. Did the chain wrap during the tide swings or when they dumped the chain on the anchor and horsed around with it? I don't know.

I think this would help Panope relate his results to the real world. I think they will show similar trends, but this could be an interesting confirmation. Some of the anchors are so new we just won't have anecdotal information for (Viking and Epsilon). The measure of a good test is whether it mirrors reality.

 

Start of with something very simple

 

Ask contributors of this forum, who use New Gen anchors, you might want to define your anchors, who has dragged their anchor and which anchor were they using.

No further detail needed - initially - but if anyone wants to add detail - don't discourage 

 

You might find - dragging of anchors is not really as common as implied.   Modern anchors have changed the frequency of dragging.  Dragging was more common and the internet has simply increased the realisation it was common - today (as more use modern anchors and understand usage) its much less common - and for many - a non event.

 

Ask - and build from there.

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sBlpz54.png

5:1 Scope.  Depth 25'+.  

Sandy Mud Resistance is an average of Winch Pulls + Propeller Thrust Pulls.  Rode included 12' of 5/16" chain.

Soft Mud Hold is derived from Propeller Thrust Pulls.  Rode included 80' of 5/16" chain.

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^^ Excellent. I think Delta would be a good reference test/baseline, since it has been tested many, many times, in many places.

A typical 35- to 40-foot boat might carry a 35-pound anchor (let's not get into the weight thing--just saying what is common). That boat would have about 1000-1500 pounds peak rode tension at 50 knots sustained (again, many variables, but I've measured some and this and ABYC specifies several times more). The range of holding for sandy mud would calculate as about 900-2700 pounds, and the holding range for soft mud about 450-1200 pounds.

A typical 25- to 30-foot boat would carry a 20-pound anchor. The wind load and the holding capacity are lower in proportion (ABYC and testing). Yes, sometimes a larger anchor will hold disproportionately to a smaller anchor (cobbles come to mind, where having a throat large enough to reach below the cobbles is vital), but not in consistent bottoms.

Panope: Anchor holding capacity is known to be ~ M^x, where x = 0.85 to 1.0, depending on who you ask. Scatter in the data can results in a very different result for any given anchor. But it might be interesting to calculate some "x" values for anchors you have in multiple sizes, and an overall average "x".  If x values are not close to one I'd take a close look at the data; variations in the bottom can make a big difference, and I've never found anchor anchor, ranging from 2-45 pounds (Claw, Mantus, Guardian G-2 to G-16) that did not follow this pattern.

The obvious conclusion is that 50% of the boats anchored in very soft mud would drag in a strong thunderstorm. Sometimes I think that is true (I've seen a lot drag some nights, but around here that usually means a harmless soft grounding). But mostly, no, the number is MUCH smaller than that. On better bottoms, the numbers still suggest a significant number would drag, and that I am sure is not true, not with good anchor set properly. 

There must be some fallacy in the logic. Most likely, short period anchor tests understate holding capacity by 20-40%. That's OK, since the effects of rate seem to treat all anchors about the same. It explains why we are not dragging.

And then there is this. How many people anchor out in 50 knots? Very, very few. A great many people never go out if 15 knots is predicted. I've heard people say they "tested" a new anchor in 15-20 knots. Ho-hum. In my case it's been summer squalls. A 50 knot storm? I'd be way up a creek, out of the wind, or in a marina! Exposed, I'd have put out a second anchor. I've done that many times, and it's easier than wondering.

I've had a few dragging incidents in 40 years. Interestingly, all were in less than 25 knots. It was super soft mud and an undersized Delta, or a Danforth (or similar) anchor that could not reset/rotate.

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I was surprised to see the Delta and Bruce dropped from the recent testing protocols, since they are baseline anchors that many boaters are familiar with. Is it the lack of available sizes to test, or are we just looking at "modern" anchors here?

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24 minutes ago, thinwater said:

 

@thinwater you have followed anchor testing for quite a while now.  Something I have been curious about with Steve's results is the relatively low scores of the rocna's. My memory (which I suppose could be faulty) is 10 years ago or so it was topping all the magazine tests. There are a few new anchors which are doing well, but there are also some 'old' ones which were definitely there in those past tests. You have any explanation why it's results seems so relatively low here. 

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7 minutes ago, Ishmael said:

I was surprised to see the Delta and Bruce dropped from the recent testing protocols, since they are baseline anchors that many boaters are familiar with. Is it the lack of available sizes to test, or are we just looking at "modern" anchors here?

Nothing dropped, Ish.

These are the "20lb'ers". 

The "45lb" range anchors contain the Delta and Bruce anchors that I have tested previously.

32 minutes ago, thinwater said:

^^ Excellent. I think Delta would be a good reference test/baseline, since it has been tested many, many times, in many places.

Yesterday, I arranged to purchase a 22lb. Delta (Craigslist).  The anchor is out of town - a friend will deliver it next week (hopefully)

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