Photos of Anchors Setting

[kas_1611]

This is really interesting for me as we use a Delta ourselves so to see how much this one is struggling in almost ideal conditions is curious, and I admit a little worrying. It would be good to do some more testing with this Delta in these conditions but sadly that sounds like it is not possible. Might have to invest in a waterproof camera ourselves and try to add our experiences to the whole. Also interested to hear from other Delta users and see more pictures (of Delta and others).

From our experience of using a Delta in the Adriatic the only time we have actually dragged was in 45kt winds when weed was the culprit. Anchored in a good sandy bed with 25-30kt winds and we held fast, if swinging around like a ping pong ball on a string. I can't recall ever seeing our anchor completely buried when we swim over it after setting but normally it is only the tips of the "ears" that are not under the surface. Don't generally swim over before we lift it the following morning but when the windlass complains I would say it was pretty well dug in.

Must admit there are now serious considerations to changing to a different design for next season.

Cheers

Keiron

[ImaginaryNumber]

Originally Posted by noelex 77

If you have a problem say at the prop, or rudder, you can attach the camera to a boat hook and take photos from angles that could not be obtained with bathyscope. Given the cheap cost of waterproof sports cameras it is an option to consider.

How would you trigger the shutter on the camera if it were attached to a boat hook?

[a64pilot]

Originally Posted by ImaginaryNumber

How would you trigger the shutter on the camera if it were attached to a boat hook?

Most have settings where they will continuously take pictures at a set time interval, often this interval is adjustable.
most can do video as well, so just put it on video.

[motion30]

I avoided an ugly incident last week due to a mismanaged fuel valve by the dumb caption (me ) anyway ran from bimini straight tru to Nassau arriving in the harbor around 3:30 am. Just as I passed under the bridge both motors in my 44' my quit. The current was running hard and immediately swep us back under the bridge. I quickly deployed my 105lb mantus and thankfully it set Rite Now. Saving me from what could have been an ugly situation. The purchase price of that anchor was well worth it that night as I was able to turn the fuel valve bleed the fuel pumps and go on my way un scarred

[noelex 77]

My Mermaid also took this great photo of the Mantus, unchanged and still beautifully set quite close to where the Delta was in the above series. The wind had reversed and you can see the underneath of our yacht in the background at the top of the photo above the float. The stern of the boat is pointing to the left and the anchor float is between the keel and rudder. You can even see the stern ladder if look closely.
The dark patch on the bottom is weed.

[noelex 77]

This Bugel copy was dropped a fair distance from our boat, but the substrate looks to be the same medium-soft sand.
It set very rapidly and has rotated almost level. With a bit more force it would completely bury the fluke. A very good result, but it would be nice to see the effects of a bit more setting force.

I did not see the drop 5m @ 4-5:1

The only other thing I would say is if you are going to use a short line make it a thin high tech line attached reasonably high up. This bulky line and knot can start to unnecessarily slightly inhibit penetration. A small foam filled fishing float will keep the line buoyant.

[kas_1611]

At present, with my eyes, that Bugel has set in a similar manner to the Delta. You can still see the shank above the surface and the sand has built up as the anchor has dug in. Unlike the Mantus which has clearly buried itself under the surface. Not casting any doubts but just wanting to share my observation.

Was wondering though what that line is used for on the Bugel, could it be a securing line for when it is on the roller?

Keiron

[noelex 77]

Originally Posted by kas_1611

Not casting any doubts but just wanting to share my observation.

No problem Keiron. I would encourage everyone one to look at the photos and make their own judgement. I have provided a description of my interpretation with most of the photos, but that is only one persons view.

One of my hopes for these photos is to provide some objective evidence so that people can form their own assessment.

If anyone wants any details clarified such as drag distance etc I will often have additional photos (you need to take a lot of photos underwater to end up with one reasonable shot) that I can post to clarify.

Originally Posted by kas_1611

Was wondering though what that line is used for on the Bugel, could it be a securing line for when it is on the roller?

Sometimes these lines on the anchor are just used to secure the it on the bow roller, but most are short floating lines to help show where the anchor is (like the one on the Mantus).

Some people use floating line, but after some time it gets clogged with sand and no longer floats. Sometimes there has been a float attached and the float has been lost or broken.

A short line with a float attached is a good idea, but in this case I think the line and bulky knot so close to the fluke are in some danger of reducing the performance of the anchor.

[bazzer]

These are all. Rey informative photos, thanks.
It shows me that this is the way to go with a anchor test rather than just pulling from the surface. What we need is a test, with photos, on different holding grounds. With the anchor sets being set correctly and then moving the boat 45,90,135and 180 degrees with a lighter pull from the boat to simulate a change in wind and tide direction. It could be done with all the popular anchors as in this thread, any volunteers?

[kas_1611]

Originally Posted by noelex 77

One of my hopes for these photos is to provide some objective evidence so that people can form their own assessment.

I can't speak for anyone else but they have been extremely interesting and enlightening from my perspective, especially seeing 3 different anchors in the same (or as close as possibly the same) conditions. Many thanks for starting this and for your input.

Keiron

[poiu]

Originally Posted by motion30

I avoided an ugly incident last week due to a mismanaged fuel valve by the dumb caption (me ) anyway ran from bimini straight tru to Nassau arriving in the harbor around 3:30 am. Just as I passed under the bridge both motors in my 44' my quit. The current was running hard and immediately swep us back under the bridge. I quickly deployed my 105lb mantus and thankfully it set Rite Now. Saving me from what could have been an ugly situation. The purchase price of that anchor was well worth it that night as I was able to turn the fuel valve bleed the fuel pumps and go on my way un scarred

Happened to me too. Exact same story and in the same spot. Actually, just in front of Atlantis. Only I was saved by a 105lb CQR.

[noelex 77]

Still at the same anchorage. Today we were joined by a German boat with a Rocna.

It was an Ovni so they anchored in quite shallow water directly in front of us. They were obviously an experienced cruising couple and dropped the Rocna very carefully. They backed down very hard on the anchor.

This is the result in 3m @ 10:1.

Even in this medium soft sand, class shows. The anchor has set rapidly. The concave roll bar anchors set very quickly. The Mantus, so far has been exceptional in this regard.

The drag marks shows a nice progressive dig down, no skips or jumps. it has rotated completely level. The shank and fluke are completely buried. If not for the roll bar there would be nothing to see. An excellent result. My only slight criticism is that there is a little bit too much heaping up of the sand rather than the fluke just diving down, but the fluke is still very well buried. Overall this is a typical top class performance (albeit in an easy substrate) from a top class anchor.

[motion30]

Originally Posted by poiu

Happened to me too. Exact same story and in the same spot. Actually, just in front of Atlantis. Only I was saved by a 105lb CQR.

Must be the curse of atlantis

[Alan Mighty]

Originally Posted by noelex 77

My only slight criticism is that there is a little bit too much heaping up of the sand rather than the fluke just diving down, but the fluke is still very well buried. Overall this is a typical top class performance (albeit in an easy substrate) from a top class anchor.

I note consistency among Rocna at #253, Buegel at #247, and Delta at #241.

Could it be that bottom is stratified, with layer of perhaps sand of one density over a layer of more dense sand or some other material?

Noelex: how distant is your Mantus anchor from this location? Has your Mantus succeeded in penetrating a layer, perhaps because of sharpness of tip or angle of attack, that other anchors have not penetrated?

Al

[noelex 77]

Originally Posted by Alan Mighty

Noelex: how distant is your Mantus anchor from this location?

The Rocna was dropped about 50m from the Mantus almost directly in front of us towards the beach.
Our anchor is about 5m off their stern. This does not guarantee the substrates are identical. Even when anchors are only a few metres apart there can be differences, or even isolated areas of rock, but I would be surprised if there is any practical difference between the substrates for the Mantus, Delta and Rocna.

Originally Posted by Alan Mighty

Could it be that bottom is stratified, with layer of perhaps sand of one density over a layer of more dense sand or some other material?

Yes. This is very common with the substrate becoming denser as you go deeper.

The ideal anchor behaviour is for the anchor to dive steeply and uninterrupted by this firmer substrate. When the holding power matches the force applied the anchor will stop. When more force is applied the anchor will once again dive deeper.

There also has to be some account of the fluke area and shape. An anchor with a larger fluke area will achieve higher holding power with the same depth of set.

In practice, as the substrate becomes firmer with depth, the anchor can no longer dive as quickly and starts simply moving backwards more. This piles up substrate ahead of the anchor. This piling up does increase the holding power, but it indicates the anchor is starting to struggle with less reserve for stronger wind. All anchors will do this. The better anchors have the ability to continue diving longer, but there are limitations, no anchor can keep diving into rock for example.


This is probably best illustrated by these two photographs of the Mantus set within metres of each other a few weeks ago. The first is set at 2:1. The anchor has completely buried the fluke but notice how much of this is piling up of the sand rather than a deep dive.


Contrast this with the photo of the Mantus in the same location set at 4:1. The anchor has immediately dived down. If you could see the drag marks it has set in 1/4 of the distance of the set with the shorter scope.



The Mantus 2:1 result was remarkable. Most anchors will not set at all at 2:1, but it does illustrate what happens as an anchor starts to struggle (in this case from a very short scope).

However, I would be cautious about reading too much into very subtle differences. It is obvious the Delta did a very poor job dragging on the first occasion, only achieving a poor set on the second after 5m then partially breaking out and only managing a very piled up sand set when more force was applied. Both the Mantus and the Rocna have managed a much better result than this, as I would expect.

The differences even between a good and an excellent anchor are very obvious and consistent. It is much harder to pick small differences between anchors that are close. On this occasion I would just give the victory to Mantus, as it has set quicker and with less heaping up of the sand than the Rocna, but both anchors have done a great job.

To refresh your memory, this is how the Mantus set here a week ago:


Compared to the Rocna: