Photos of Anchors Setting

[hoppy]

Originally Posted by BigBeakie

Hoppy: the issue is the weakening of nylon with repeated cycles of stretching, so if that is nylon going through the rubber thingamabob, it doesn't solve the problem, seems to me.

My thought is that you can use a thicker/stronger line that is less prone to stretching and use the rubber spring to absorb the shock and be what breaks first.


Another thought, if you know you'll be anchoring in storm conditions, add 2nd snubber as a backup incase the first fails.

[BigBeakie]

Hydra,

Ok, got it now You are trying to slow down the boat "springing back" during a lull, using a parachute anchor. But do you think there would be THAT much stretch? I think the parachute anchor would sink unless you bouyed it with a float, and then there are cross currents to think about that may run acros the wind direction.....hmm, could get messy, and as you mentioned, tangles in the rudder and prop.

Hoppy,

I have seen cats use these off both bows, and in the future will try to speak to owners using them for some feedback. Maybe someone here has tried them. I used something similar ( just a really big thick O-ring) in my 6 meter fishing runabout and it worked great for wave surge.

[0urh]

Would a 4WD Snatch Stap work as a snubber? Available in different lenghts and breaking capacities, relatively cheap ($80). Google 'snatch straps' for more info

[noelex 77]

The wind has only been very light so the anchor will have not changed, but my mermaid braved the elements for this much better photo.

From this perspective you can see the roll bar is at least 2/3 buried. That puts the fluke a long way down. This sort of sand is quite hard and the light weed cover and especially the weed roots just under the surface add further to the resistance. It needs a good anchor to penetrate the surface instead of just piling up the substrate. The Mantus has dug straight down and despite its deep bury and rotation necessary from the initial set, has barely moved.

This is a big anchor, but the slight additional weight and cost is forgotten when it keeps you safe without budging in these conditions, especially with basic errors like losing the elasticity of the snubber .

[hoppy]

What's the water temp at the moment and what part of Greece are you in?

[JPA Cate]

Ah, bless the mermaid, what a great pic!

Well done, my dear.

Ann

[noelex 77]

Originally Posted by hoppy

What's the water temp at the moment and what part of Greece are you in?

We are in the Cyclades. The surface temp is about 17°C (62°F). It gets a fair bit colder close to the seabed.

I am wimp. I hate cold water so its good to have a mermaid .

[hoppy]

Originally Posted by noelex 77

We are in the Cyclades. The surface temp is about 17°C (62°F). It gets a fair bit colder close to the seabed.

I am wimp. I hate cold water so its good to have a mermaid .

Looking at poseidon I guess I will have something similar in the Ionian.

Just got my new dive housing and hope to make a visit in a few weeks. Not sounding like I'll be wanting to get wet on that visit. I think I'll want to see 20 before I dip my toe in even with a 3mm wetsuit

[monte]

27 degrees in Guadeloupe
Deshais is pretty busy, lots of good moorings here but all taken so we dropped the Kobra 25kg in 10m @ 3:1. Id prefer more scope but its a bit tight with other boats. Still a nice solid set and not budging with 2x40hp@2500 RPM for a couple of minutes. I noticed a lot of old ship chain on the seabed here so lookout! Maybe best to add a trip line.
Sorry the pics not the best but about an 8m dive was the best I could manage after a daysail from Antigua.
Chances are ill be on anchor watch, or rather neighbouring boat watch tonight anyway. Someone came in after us, dropped there anchor (rusty danforth that looked about 10Kg)about 20m upwind (East) of our anchor, let their chain freefall for a minute or so, and ended up anchored 10m west of our transom. I thought they would figure out there was something wrong with the geometry there and reanchor but no...
I usually wait a while to let people know they may be too close, rather than glare at them as they enter the anchorage and stand on deck with the bitchwings. I guess ill be putting some fenders out and hoping it doesnt go SE tonight

[noelex 77]

A new anchorage and a very interesting result.

The Mantus held full reverse as per normal, but rather than an immediate instant dig in, it gave a slight, but a very uncharacteristic skip of a couple of feet when reverse power was applied.

The Mantus has hit a large subsurface rock (it looks like two rocks in the photo, but it is actually a large single rock). Consequently the anchor has taken about 50% longer than normal to set. You can also see a lot of piling up of the substrate. Both of these characteristics indicate the anchor is struggling to penetrate the bottom properly. Even excellent anchors are defeated by rock.

Many of my underwater photos have shown this type of behaviour from other anchor designs simply in hard sand. This piling up rather than digging in is a classic sign of an anchor not performing well.

Hidden hazards (both natural and unfortunately man made garbage) are surprisingly common. It is a great help to have an anchor that normally sets in a shank length rather than a design that takes many metres to start digging in. This greatly reduces the chance of hitting these sort of obstructions. The Mantus is great in this regard, but as you can see this reduces, but does not eliminate risk.

Even with the best anchor equipment and technique don't forget an anchor alarm. An anchor can be disrupted by a rock, an old towel, discarded spinnaker, tyre or tree (don't ask ). In some circumstances it can hold full setting force, but not be performing normally.

In this case the anchor looks to have started penetrating the sand under the rock and with a forecast of light winds we felt a re-drop was not needed. Let's hope we are right .

[DeepFrz]

Noelex, I think that you are selecting snubbers that are to weak for the job. You really do not need a lot of stretch for them to do their job properly. A heavier line and splice should stand up well to the task. Try a heavier line, one or two sizes larger than what you have been using and see how that works.

[Tomaz473]

I am using a rubber mooring line spring on the snubber like Hoppy pictured above.
I was cruising with it for two years in Mediterranean and mostly in Caribbean. I was anchored most of the time.
Life on the hook was much nicer after I installed this spring. Easy motion and no jerking.
I could also reduce snubber length to just 2m. The spring made all the work.

[noelex 77]

Yesterday we had 25+ knots at about 120 degrees from the original setting direction. I was interested to see if the Mantus had managed to "shuffle" around to the new direction despite the poor set caused by the rock.

Below is the result.

You can see the Mantus has managed to rotate without otherwise moving .

Many people imagine their anchor breaking out dragging along the bottom and then having to reset when a change in wind direction occurs. This is actually very rare if you have an anchor that rotates well. In the five years I have owned the Rocna and the one year I have owned the Mantus I have never seen either anchor do this and, as you might of gathered by now, the anchor gets plenty of attention .

However, to "shuffle" (ie to remain buried and not move other than rotating) requires a reasonable set and substrate. The disruption caused by the rock tested the limits, but the Mantus has managed to "shuffle" perfectly. It is still not a great set with a significant list and heaping up, but from this position and free of the rock the Mantus has started to bury itself nicely.

The ability of an anchor to rotate in a competent manner is a very underrated and little discussed aspect of an anchor's performance. There are large differences in this regard between the various anchor designs. It is good to see the Mantus still shuffling in very difficult circumstances.

[noelex 77]

Another anchorage and no rocks

This time sand with a light weed cover. The Mantus has always set in a very short distance and this is another example. It is difficult to imagine how it manages to bury in such a short space. 7.2m @ 4.5:1

[JPA Cate]

John & Angela,

I just clicked on your Mermaids & Anchors link. I am so sorry to hear of malicious rumors being spread.

Personally, I think this thread you started is a wonderful service, and I hope more and different anchor pix are provided by other CF members.

Thank you both.

Ann