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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

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25 minutes ago, Max Rockatansky said:

70A23682-A266-46D3-BCC2-6DACEE1F9087.jpeg

Ooooooo, so bright and shiny.

I have to give Nick a call to borrow a 37# to see if it will fit my current arrangement. It helps he's a few hundred feet from our boat.

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will be really interested in objective testing of the excel - the 'next gen' label has been so tightly linked to concave shape it is almost part of the 'definition' of the term.  Will be fascinating if convex can in fact do just as well.

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7 hours ago, estarzinger said:

Is it noteworthy that the two top "performance" average anchors are also two of the heaviest?

Perhaps.  I need the upcoming pull numbers to be sure.

Note that at the other end, the worst performers are not the lightest.

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Progress continues slowly on the new boat:

A bracket for the "get home engine" (Panope's short shaft dinghy engine).

NBV1r5C.jpg

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3 hours ago, Panope said:

Perhaps.  I need the upcoming pull numbers to be sure.

Note that at the other end, the worst performers are not the lightest.

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Progress continues slowly on the new boat:

A bracket for the "get home engine" (Panope's short shaft dinghy engine).

NBV1r5C.jpg

If we get to meet, looking at this… I’m kinda leery for you to see the workmanlike fabrication on my boat. Nice work

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5 hours ago, Panope said:

Note that at the other end, the worst performers are not the lightest.

yea, it is an interesting ranking.

Have you reached a 'tentative' conclusion that concave is NOT as significant a design feature as everyone thought some little while ago?   Or is this still too preliminary to reach even a tentative conclusion? I have not followed where you are in your 'science' process.

I did pull and veer testing down in Puerto Williams, below the high tide mark on the stony beach with 50-60kgs anchors.  I had a different selection that you have done. But my top 3 were Rocna/Bruce(actually manson Ray)/Supreme - very close but in that order.  I gave away all the other anchors and kept those 3 and rotated them on my bow, and in real use the Ray was by far the most 'reliable' with the ROCNA 2nd (eg it would not let go when I thought it was well set, unlike the rocna). I ended up with the Ray on my bow and the rocna as my spare in the stern locker and gave away the supreme).   Quite a different rank order from yours - but different sizes and perhaps different bottom conditions - the most difficult bottom for me was the 'smooth hard under surface (eg glacier carved stone or coral) with variable layer of mud or sand over it').  These anchors were all so big that in a 'good' (sand or mud) bottom I did not worry about even the worst design - I just dropped them and did not really even bother to set them. I don't think I was biased - but who knows.  I wish I could have tried a big spade, but there was some problem, either back then they did not make a 50/60kg version, or they could not get one to me (I was at the end of the earth, but the other manufacturers managed to figure a way).

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5 minutes ago, cje said:

Max, your snout looks my FP Fidgi that presently sports a 20kg MP. Did you have a problem with it?

oops MS- charles manson darwin and the supremes.  That's what I call it.

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8 minutes ago, estarzinger said:

Have you reached a 'tentative' conclusion that concave is NOT as significant a design feature as everyone thought some little while ago?

Who is everyone? 

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25 minutes ago, cje said:

Great stuff max. 

Steve told us to drill the entire manson supreme's fluke with 1/4" holes like pegboard. 

What a waste of $ on the excel.

 

Could you expand on that? I think I'm not understanding.

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I'm with you Max. At this moment without playing with a Viking or M2 I personally feel Excel is the best anchor.   

Steve drilled holes in the MS and it performed. Go thru his vids.

Is it 1/4" holes or 3/4" holes and where are they located. They work.

I'm no expert but- Its all about soil recolonization or other words. Sorta like foils, leading edges of a fluke are sharp and bite then trailing shapes bring things back together again, or not.

It's the not part we don't want.

Thanks for all the effort S.

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4 hours ago, estarzinger said:

Have you reached a 'tentative' conclusion that concave is NOT as significant a design feature as everyone thought some little while ago?   

Yes.  

It appears that the DETAILS of the design might be more important than the general concept.

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42 minutes ago, Panope said:

It appears that the DETAILS of the design might be more important than the general concept.

interesting.  I dont know if that makes things simpler to understand or more complicated - i guess perhaps more complicated because there are so many degrees of freedom for the details..

I know Peter specially sharpened the blades on my Rocna (he hand built it for me). He thought the edges on the retail rocna's were not optimally sharp and that it made a meaningful difference.

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8 hours ago, estarzinger said:

interesting.  I dont know if that makes things simpler to understand or more complicated - i guess perhaps more complicated because there are so many degrees of freedom for the details..

I know Peter specially sharpened the blades on my Rocna (he hand built it for me). He thought the edges on the retail rocna's were not optimally sharp and that it made a meaningful difference.

I have sharpened flukes (Danforth knock-off), as well as some other minor reshaping, the difference was substantial. I'm partially guessing, but I think it is less about the ability to engage, than the ability to cut through trash and into firm soil.

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The soft shackles that Evans made for me have arrived (This like having Hattori Hanzo build you a sword).  They are almost comically large but this size is very nice for handling, especially with gloves.  

Today, I used the shackles during the "bollard pull" (zero boat speed) testing of the new motor/prop.  Both the shackles and the Engine worked great.

It took several attempts (over a couple visits to the local Yamaha dealer) to properly convey just what my propeller needs are.  The words that finally did the trick were "I want a tug boat".   Once they understood, I let them select a propeller and they nailed it.

This prop (mounted on engine in the pic) is amazing.  It made over 1300 lbs thrust (@5100 rpm on a 6000 rpm, 90 hp motor).  This is over 250 lbs. more thrust than the previous "best" prop that I have experimented with (old boat, same hp engine).

Note the large diameter prop hub which allows water flow to mix with the exhaust gasses prior to exiting the hub.  I have no idea how/if this works, but again, this prop pulls REALLY hard with no ventilating, no cavitating, no surging, and no vibrating.  

The large hub makes the prop appear smaller than it is.  Prop is actually larger diameter than the other pictured propeller and has substantially more blade area where it counts (outer half).

The only downside to this prop is low boat speed.  Engine reaches redline (6000) at just over "half" throttle with boat speed of about 23 knots.  A reasonable rpm of 4500 (1/3 throttle) gives 16 knots.  Boat planes nicely at that speed.  

7aEUniX.jpg

I10KT4Z.jpg

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Evans, in case you missed it, here is my first veer test video.  17 anchors back to back in the same test.  

It is a brutally long video, but if you manage to make it to the 49:45 mark, that is where I make (what I think is) a interesting (and rare) correlation between general anchor configuration and performance.

 

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32 minutes ago, Panope said:

 interesting (and rare) correlation between general anchor configuration and performance.

I have to admit I fast forwarded to it, but yes, interesting.  In our early cruising years there was a theory that you needed to carry different anchors for different bottoms.  When the 'next gen' anchors came out, that was mostly put aside, for 'the biggest single anchor you can fit' theory.  IDK, perhaps you will swing the pendulum back a bit to an understanding of different ranked performance in different bottoms.

This picture hurts my soul. 

winch.thumb.jpg.623a1d9e3c98d670e63cb23bfff719a5.jpg

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16 minutes ago, estarzinger said:

This picture hurts my soul. 

winch.thumb.jpg.623a1d9e3c98d670e63cb23bfff719a5.jpg

Only a test!

Not only did need a quick lash-up, I wanted to see a Dyneema bowline under load, with my own eyes.

Might have been creeping. If it was, it was very slow (3/8" line, 1100 lbs.).

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12 minutes ago, Panope said:

Only a test!

Not only did need a quick lash-up, I wanted to see a Dyneema bowline under load, with my own eyes.

Might have been creeping. If it was, it was very slow (3/8" line, 1100 lbs.).

Yea, all good, but I could hear it crying all the way here. I would expect a bowline to start really slipping at about 15-20% of breaking strength - so I guess like 3-4k lbs in 3/8".  Slipping point depends quite a bit on how fast you bring on the load and on the specific coating (and its condition) on the line. 

A figure 8 loop and a water bowline are both 100% secure/non-slipping if you really need a loop knot in dyneema, so can hold more than twice the load of a regular bowline. So they are worth learning, getting used to if you start using more dyneema - but ofc still again 50% less strong than a spliced loop. 

There are actually several ways to put an 'integrated' soft shackle into the end of that line.  But it seems better to me to put a spliced loop and then use whatever attachment device is more appropriate. 

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On 6/12/2021 at 4:35 PM, estarzinger said:

 A figure 8 loop and a water bowline are both 100% secure/non-slipping 

Evans, I can see a need where I might need to make a temporary loop "mid span" of the dyneema.  Would a "water bowline on the bight" be of any benefit?  

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1 hour ago, Panope said:

 a temporary loop "mid span" of the dyneema.  Would a "water bowline on the bight" be of any benefit?  

Are the two legs before and after the loop still going to be loaded?  If so I would be tempted to use an alpine buterfly.  It has the best load path thru the knot).  I would see while tieing it if there was anyway to throw in an extra loop or clove hitch feature like the water bowline has.  It might slip, but probably at hhiger loads than you are pulling and it would (I think) just compress the loop so the slip-fail mode is 'safe'.

There are also various gripper knots (like the icicle and Klemheist (and such) which will actually hold a decent load on dyneema so long as you use small dacron or vectran cord.  They will ultimately slip, and your main winch line is relatively skinny for them.

Another alternative is to make up a piece of dyneema with an eye splice.  Then just straight bury the standing part of that piece in your mid span.  Gives you an eye hanging out - stronger than the knots, but does still weaken the system (because of the stress riser at the exit point) by about 20%..

The 'loop mid span' is one of the few applications for which a great solution has not been discovered yet.

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1 hour ago, estarzinger said:

Are the two legs before and after the loop still going to be loaded?

No, just one leg.  Might be useful for breaking out/retrieving anchors.  A strategically placed cleat might be better.

These mid span knots have peaked my curiosity.  I can safely test (and afford to test) to destruction, 1/8" Dyneema.

Does Dyneema "scale" well?

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48 minutes ago, Panope said:

Does Dyneema "scale" well?

across the 'normal' yachting range of say 3mm to 10mm it scales pretty decently.  The knots ultimate breaking strength will almost certainly be in the 'normal knot' range of 45-55%.  But their slipping threshold can vary a lot by knot design.

slipping is hard to test accuractly for - it is not hard to say this slips easily, or hard, or not at all, but putting actual numbers to it is tricky because they depend a lot of pull rate and coatings and surface quality.

With 1000lb pull on 1/8" amsteel you should get a decent slipping indication. But you are going to be below what I would anticipate to be typical breaking loads. But if you can get upto 1500lbs pull then I would think you should be able to break all the knots in 1/8"

48 minutes ago, Panope said:

No, just one leg. 

In that case, then I think the easiest thing would just be to tie in a figure 8 loop.  It can be untied after being loaded - although dyneema knots do tighten up more than in dacron because of the slipperiness so I would not be surprised if you needed a spike to get it apart.  There is also a figure 9 loop which might be a bit easier to untie (just a guess I have not tested it).

Tubboat hitch is useful for pulling - normal cleat hitch on a smooth cleat will slip

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1 hour ago, Blue Crab said:

Seaworthy Lass on the nice forum is a very knotty girl. You pros probably know her already.  Her hub took all those pics of anchoring in the Med some years back.

She would want steve to do something with a zeppelin knot - that is (or was) her most favorite :)  (and yes there is a zep loop)

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4 hours ago, estarzinger said:

She would want steve to do something with a zeppelin knot - that is (or was) her most favorite :)  (and yes there is a zep loop)

Oh man, don't get me started on her zeppelin proclivities. I barely got out alive! She understands AVS without googling too. 

Fuck I love this pace competent people.

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27 minutes ago, Autonomous said:

Would some version of the cut splice work?

 

There are a couple semi-decent solutions for a permanently placed loop.  But I think he wants to be able to placed it at different locations based on water depth. 

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7 hours ago, estarzinger said:

slipping is hard to test accuractly for - it is not hard to say this slips easily, or hard, or not at all, 

That's good enough for me.

 

7 hours ago, estarzinger said:

She would want steve to do something with a zeppelin knot - that is (or was) her most favorite :)  (and yes there is a zep loop)

I used to be a "2 bowline" guy for joining (non Dyneema) lines.  I am now a zeppelin convert.

 

1 hour ago, estarzinger said:

 But I think he wants to be able to placed it at different locations based on water depth. 

Precisely.

 

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I am just now, getting started making up the Dyneema Rodes. 

Here is the (current) program for the Dead Man Rode.  100% Dyneema sections "chained" together with spliced eyes. 

First section is 100' long, attached to the anchor (FX-85) with a 5/8" galvanized Shackle.  

The other sections are 15' long.  This is the "on-deck" working distance I have between the winch and the bow roller. 

The winch line will attach to the rode with a soft shackle that will be preloaded (and perhaps whipped) to each rode "junction".  Reason for the "preloaded" shackles is it will be near impossible to pass anything through the rode eye when the rode is under under high load.

All these eye splices are eating up quite a bit of Dyneema (about 30 inches each).  I would be open to alternative methods (of creating mid-span attach points) that consumed less material while maintaining most of the line strength.

rB0DskV.jpg

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9 hours ago, Panope said:

  I would be open to alternative methods (of creating mid-span attach points) that consumed less material while maintaining most of the line strength.

 

That is nice looking work . . . but  . . . . I wonder if bare dyneema is the best material for this.

Some good quality bigger diameter dacron double braid (or a dacron single braid like TENEX), would I think have sufficient strength, sufficiently low stretch.  Would hold Klemheist and Prusik and  Rat-Tail Stopper type loops for mid-span pulling points.  And would lose less strength with mid-span knots and they would be easier to untie - a series of alpine butterfly's in a dacron line would be less elegant than what you are doing there but I guess would work for a lot less money and effort..

If you needed more strength and less stretch than that (which I dont really think you do) then you could use a dyneema cored dacron covered double braid.  Rather more expensive, but higher strength/lower stretch while still having a cover you can grip.

idk - 

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as an aside, you can make soft shackles out of Tenex (and NER's REGATTA BRAID) and they are relatively stronger (compared to breaking strength) than in dyneema, because dyneema is more bend tolerant and has more friction.  You can use the same splices as with dyneema single braid but can use less bury because of the extra friction.

A lot here depends on how strong you are going to pull, and how much safety factor you want, and how big a rope you are willing to handle.  You can get tenex in 'industrial' sizes but I would guess that something somewhere in the yachting size range 1/2 9/16 or 5/8  would do it for you.

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Tenex looks good (great for the ability to knot), but I think Dyneema will be preferable because of less stretch.

I will often be working with 400 feet of rode. Even at only 1% stretch (Dyneema), 4 feet will make it hard to know (in real time) if the anchor has stopped moving.  At 3% stretch, the Tenex, by comparison, will seem like a rubber band.

Also, the much greater bulk of Tenex (5/8" 'wet' dacron vs. 3/8" Dyneema) will make dealing with large piles of the stuff quite a bit more of a struggle.

I've got 200 feet of the Dyneema flaked into a brown paper grocery bag.  It can be lifted by the cheesy paper handles no problem.  Lot to be said for that.

 

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1 hour ago, Panope said:

.........one more reason for Dyneema:

ok, dyneema it is.

What you are doing is the strongest best way.

I can imagine several 'easier' ways - one for instance using dyneema climbing slings https://www.outdoorgearlab.com/reviews/climbing/climbing-slings/mammut-contact-dyneema) as the puller loops embedded in your main rode.

But they will all be weaker than what you are doing.

One advantage of what you are doing is that if you damage a section of the rope, it will be easy to replace just that section.

 

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15 hours ago, Panope said:

All these eye splices are eating up quite a bit of Dyneema (about 30 inches each).  

 

What bury are you using?  You can do 45x (or 50x just for a little extra) perfectly fine since you are doing nice lock stitching.  There is zero tested advantage to going to 60 or 70x - that has just been rigger 'more is better' marketing creep.  Do a nice taper and a nice stitching and you are all good)

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Bury is 53x (20 inches, 3/8" line).  The other 10 inches is consumed by the eye (half of the eye), and the "lost" length due to the "Chinese finger trap" shrinkage effect.

Between the 2 rodes, it looks like there will be about 25 eye splices consuming 62 feet of line.  

Its only money. 

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On 6/16/2021 at 6:43 PM, Panope said:

I am now a zeppelin convert.

14 hours ago, estarzinger said:

 Klemheist and Prusik and  Rat-Tail Stopper type loops- a series of alpine butterfly's

On 6/16/2021 at 11:18 AM, estarzinger said:

a zeppelin knot -  (and yes there is a zep loop)

Sure, but can you tie a double overhand figure-eight fisherman's bird glove? (It appears at 2:45 in the epic battle in the link :-)  but worth watching the whole thing from the beginning for context :-)

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16 hours ago, Panope said:

Its only money. 

It will belong in a museum whenever you retire it.

Am I correct, the reason you need to do this is because of the (limited) winch drum capacity?

Just trying to understand what makes your application so relatively unique.  I guess in commercial applications you either have drums which are sized/designed to fit the whole line or capstans where you can pull endless line. And for "variable rigging" applications chain (including the webbing chain) is generally used.

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3 hours ago, estarzinger said:

Am I correct, the reason you need to do this is because of the (limited) winch drum capacity?

Yes.

Additionally, the winch will do "double duty" as not only the 5,000 lb. dead-man anchor puller, but also as a "windlass" for retrieving the test anchors, which means being able service multiple rodes (I count 4 different rodes that will need servicing on a typical outing).

Also, having the rodes "free" of the drum, means that I can deploy/retrieve the bulk of the rode by hand which is much faster than the endless waiting for a high power drum to winch wind/unwind.

This winch set-up, the fancy Dyneema rodes, the bridle, and the new boat/motor combination are all part of a system that I designed to meet the following parameters:

-A floating anchor test platform that can relocate itself on the water at 10+ knots.  

-A platform that can be launched/retrieved at normal launch ramps and can be trailered behind a plain jane pick-up truck at freeway speeds (East coast, here I come).

-Able to carry 1,000 lbs. payload (Anchors, chains, winch, etc.).

-Able to make over 1,000 pound of propeller "bollard pull" (I get 1,300 lbs.- Woohoo.)

-Have "vectored thrust" (a must have for the "veer tests")

-Able to pull a Dyneema dead man anchor rode at a constant rate at up to 5,000 lbs.

-Able to mechanically retrieve the last 30 or 40 feet of test anchor rodes (Dyneema, nylon, and chains).  

-Platform needs to be durable with low maintenance.

-Platform needs to be reasonably seaworthy a chop that might spring up on me.

-Platform needed to be affordable (by me) and retain good resale value.

 

 

 

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Well don't waste your time in FL, Steve. Mostly sand which is easy and no anchor will hold in the one mm of sand over the hard pan in the south. If you must, just use the ramp in Coconut Grove near Miami and you'll have most of Biscayne Bay to not be able to anchor in safely due to the single silly mm of sand.

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2 hours ago, Panope said:

This winch set-up, the fancy Dyneema rodes, the bridle, and the new boat/motor combination are all part of a system that I designed to meet the following parameters:

-A floating anchor test platform that can relocate itself on the water at 10+ knots.  

-A platform that can be launched/retrieved at normal launch ramps and can be trailered behind a plain jane pick-up truck at freeway speeds (East coast, here I come).

-Able to carry 1,000 lbs. payload (Anchors, chains, winch, etc.).

-Able to make over 1,000 pound of propeller "bollard pull" (I get 1,300 lbs.- Woohoo.)

-Have "vectored thrust" (a must have for the "veer tests")

-Able to pull a Dyneema dead man anchor rode at a constant rate at up to 5,000 lbs.

-Able to mechanically retrieve the last 30 or 40 feet of test anchor rodes (Dyneema, nylon, and chains).  

-Platform needs to be durable with low maintenance.

-Platform needs to be reasonably seaworthy a chop that might spring up on me.

-Platform needed to be affordable (by me) and retain good resale value.

 

 

 

I forgot to mention a very important parameter:

-Able to give continuous, realtime load info for the test anchor (that one was harder to achieve than one might think).

A "pontoon boat" could have been a good choice although it would have had to be a really big one because multihulls generally have low "reserve buoyancy" (need lots of buoyancy so the winch does not pull the boat under).

Also, I can imagine a very low resale value of a "salted" pontoon boat that was used in a working environment (I'll trash it).

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7 hours ago, Panope said:

 Blue, I reckon a "failed" anchor set/test is just as valuable as a successful result.  

This. Any of the anchors will work in good conditions.

Sand over hardpan is an excellent example of a trick-bottom that can fool anyone, depending on the thickness of the sand.

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6 hours ago, Blue Crab said:

I always set two in that area and never regretted the extra effort. 

Please explain how (in-line, V, or other) and why it works (more friction, better chance of hitting a good spot, etc.).

Just curious. There is more than one right answer to this question IME.

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29 minutes ago, thinwater said:

Please explain how (in-line, V, or other) and why it works (more friction, better chance of hitting a good spot, etc.).

Just curious. There is more than one right answer to this question IME.

Dove on each and every Bahamian set and wedged and cajoled Danforthish anchors into crevices. 

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Over the years, I've made quite a few soft shackles without the buried tails.

These are the first 3 (of 9) that I have tried with buried tails.

Material is 5/16" Spectra.

First one is functional but is too small for easy handling.  Also, the (buried) tails are a little short.  This shackle consumed 48" of line.

Second one was better. Consumed 60 inches of line.

Third version is the one I will replicate.  Consumed 66 inches.

DMXBcPM.jpg

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@thinwater, we know you think that the V is better than the Bahamian (180 opposed).

But those of us who are actually here in the Keys do not agree, because we have almost daily experience with thunderstorms that reverse wind 180 degrees, in which case a V-set will invert, pull out, and then you have a fucking mess on your hands.

Bahamian moor is not only for reversals and marl bottom but also for current, which is another big factor in the Keys.

Ive been spending the last five years living aboard full time anchoring between the Keys, Bahamas and northern Gulf, and my entire first year was spent up and down the Keys. Virtually all of this time has been on the hook. I have dragged only once, and I described my experience above.

If I were rigging a longterm mooring here in the Keys, I’d follow the advice of the conchs and set three Danforths in a triangle. By diving it as BC describes above.

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On 4/14/2021 at 10:35 AM, Russell Brown said:

I'd be more concerned about other things when buying an anchor than it weighing exactly as advertised.

I am quite surprised at Steve's finding the small details did make a bigger difference than expected.

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6 hours ago, Panope said:

Over the years, I've made quite a few soft shackles without the buried tails.

These are the first 3 (of 9) that I have tried with buried tails.

Material is 5/16" Spectra.

First one is functional but is too small for easy handling.  Also, the (buried) tails are a little short.  This shackle consumed 48" of line.

Second one was better. Consumed 60 inches of line.

Third version is the one I will replicate.  Consumed 66 inches.

DMXBcPM.jpg

Apropos of nothing, you've certainly gotten your money's worth out of that tape measure.

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10 hours ago, Panope said:

Third version is the one I will replicate.  Consumed 66 inches.

Nice.

As an aside, I would comment that the one area of the burried tail soft shackle design which has not been totally optimized is the loop. It is agreed that you want the loop (when it is tensioned) big enough to not be crushing the legs inside it and small enough to not be able to slip over the knot.  But that leaves a pretty wide size range which has not been well tested. Perhaps it makes no difference within that range.  I prefer to be on the smaller end, because I understand what is going on with loading at the base of the stopper knot but loading up higher on the knot seems like it is possible to get some sort of unexpected result.  But I never did (and am not aware of anyone else doing) a test string exploring the size range.

There are also some alternative constructions for the loop.  The single simple pass thru is the most straightforward but is a weak point in the design and there are ways to make that failure point stronger.  We tested several possibilities and did find some approaches which significantly strengthened it, but did not exhaustively explore the possibilities, and no-one I know uses any of these alternatives.  It seems to be 'strong enough' in its base design that "added strength for added complication" is not generally wanted, and people just use bigger diameter line if they want stronger.

I would be curious if a 'rat tailed' stopper would pull enough load on your 100' rode (before slipping) to act as the pull point when you needed to recover a deeply burried anchor.  That would be I think the preferred option ( least damaging to the rode, easiest to use) if it works.  I have tested the slipping of many of the gripper type knots but I did not include the rat tail approach.  It is usually used on much bigger diameter lines (shipping mooring and tow lines) so I dont know how well it will scale down to your 10mm rode.  I believe (but am not 100% sure) the stopper cord needs to be rather smaller diameter than the rode to grip well.

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2 hours ago, estarzinger said:

It is agreed that you want the loop (when it is tensioned) big enough to not be crushing the legs inside it and small enough to not be able to slip over the knot...

I went with a loop size that is just a bit loose on the legs.  However, I can imagine this changing a bit after tensioning the button knot.  Or perhaps not?

 

2 hours ago, estarzinger said:

I would be curious if a 'rat tailed' stopper would pull enough load on your 100' rode (before slipping) to act as the pull point when you needed to recover a deeply burried anchor.  That would be I think the preferred option ( least damaging to the rode, easiest to use) if it works.  I have tested the slipping of many of the gripper type knots but I did not include the rat tail approach.  It is usually used on much bigger diameter lines (shipping mooring and tow lines) so I dont know how well it will scale down to your 10mm rode.  I believe (but am not 100% sure) the stopper cord needs to be rather smaller diameter than the rode to grip well.

I had not heard of that one.  Looks useful.  I'll try it and report back.

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5/16" Spectra (main line)

1/4" hardware store crap line.  Nylon? (gripper line).

With 4 wraps, held 400 pounds briefly, then slipped and would only hold about 100 lbs.  Weird.

With 7 wraps, held 700 pounds briefly, then slipped and would only hold about 100 lbs.  Weird.

UkdDsvW.jpg

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.....with 3/8" "spun dacron" gripper line ( main line 5/16" spectra):

With 5 wraps, held 300 lbs briefly, then slipped and would hold 200 lbs. With continuous slipping.

2v5eDw6.jpg

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.......1/8" Spectra:

Standard bowline: continuous slipping at 250 lbs. Easy to untie.

Bowline on the Bight: continuous slipping at 250 lbs. Easy to untie.

Water bowline on the bight: holding fine when the line broke (at the anchor point stopper knot) at 900 lbs. Impossible to untie without tool or tooth.

Q3az0F2.jpg

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Klemheist knot on 1/8" spectra (1/8" para cord sling):  slipped continuously at 50 lbs.

Prusik loop on 1/8" spectra (1/8" para cord sling): slipped continuously at 20 lbs.

Figure 8 loop in 1/8" spectra: knot holding fine when line broke at 1000 lbs. (at knot).  Impossible to untie what was left of the knot.

dqO65Y4.jpg

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Klemheist on 3/8" Ultrex (Sling - 1/4" shitty hardware store line): Holding fine at 800 lbs. when sling parted.

Impossible to untie without tools or tooth.

Note that the sling parted just where it exited the klemheist "blob" and was basically 'cut' in half by squeezing Dyneema (I think).  Note that the sling did not break at Zeppelin Bend.

iv0nSzP.jpg

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the rat tail - not sure if you did or not, but when you tie it on you need to make the loops tight up against each other because they need to then be able to stretch out apart and that acts as a clamping action.  If you tie it initial spread out, then it can not spread further and there is no extra clamping.

But from your other tests . .. I guess none of the gripping options are going to be able to hold enough.

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for the 'pulling a strongly burried anchor' scenario . . . I wonder if the 'standard' anchor float/retrieval line would be the best option - a line tied to anchor crown that will float up to the surface with a loop to hook to.  That would seem better/easier than trying to get a pull point in your 100' rode.

However, Idk, that might interfere with your testing in some way, with the cam rig or something.

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1 hour ago, estarzinger said:

the rat tail - not sure if you did or not, but when you tie it on you need to make the loops tight up against each other because they need to then be able to stretch out apart and that acts as a clamping action.  If you tie it initial spread out, then it can not spread further and there is no extra clamping.

But from your other tests . .. I guess none of the gripping options are going to be able to hold enough.

I think the first rat tail was tied a little "spread out", but I clued onto it and tied the rest snugly. 

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