Photos of Anchors Setting

[noelex 77]

I will count the time taken for the anchor to hit bottom next time I drop. This will only give the average speed. I think the anchor is accelerating as it falls. So the speed as it hits the bottom will be higher than this average.

My camera will do 120 fps at low resolution and this might be fast enough to film the chain going out. The number of links would give the distance moved in each frame and the velocity could be calculated just as the anchor hits the bottom. More projects .

I think the speed might alter from drop to drop even if other variables (depth, type and weight of anchor etc) were constant. The anchor has to pull the chain out of the locker and sometimes when the chain heap collapses, the last bits of chain can get buried, taking more force to pull out.

You do need to be careful when using this technique, that you don't drop a whole pile of chain in one spot. The ideal when setting is to lay the chain out in nice neat straight line as the boat moves backwards. So as soon as the anchor hits the bottom you need to tighten the clutch. The clutch on my windlass is quite adjustable, a bit like a drag on fishing reel so I can set it with the right force so as the boat moves backwards the chain is let out correctly.

[noelex 77]

Back to clear water 😃.

This is a sand anchorage with loose rock.

It is a reasonably tight bay, although with careful positioning a good scope is possible. You can see the swinging room is confined by a small island to the south, an isolated crop of rocks (to the NE) a pier and some moorings that have been laid by fishing boats. These sort of anchorages are great in summer, as they put other boats off, particularly as the only map available has just a single isolated depth point listed. You have to guess what the depths may be elsewhere. Even in peak season few boats anchor in this sort of spot overnight.

One of the advantages of a good quality, oversized reliable anchor is the ability to use these anchorages with confidence.

In winter there is more need for caution, as the winds are stronger and the forecasts are less accurate.

Anyway, you can see the Mantus has set well. Despite my previous recommendation, the boat was facing 80 degrees from our backing direction when we dropped, in an attempt to place the anchor exactly midway between all the hazards. You can see the setting mark in the sand as the anchor swung around. This has left quite a reasonable list.

[Jim Cate]

Nolex, I've been thinking about what actually happens when the anchor impacts the sea bed when using your "express elevator" dropping technique. Seems to me that considering the drag from the chain, the anchor will always strike in the fluke up, roll bar down position... could be wrong, but I think this attitude is most likely.

If so, it's hard for me to believe that the impact will have much effect upon the setting of the anchor, for the tip of the fluke will likely be outside the immediate impact area where breaking up the surface has occurred. In softer substrates where the anchor might actually drive vertically into the bottom, well, it will dig in regardless... that's what it is designed to do! Whaddya think?

I guess that enticing the mermaid to be down there with a video camera to actually record the event might be informative! If you do that, perhaps she should wear a hard hat??

BTW, I too enjoy seeing the big cloud of debris flying up upon impact... kinda cool!

Cheers,

Jim

[noelex 77]

Originally Posted by Jim Cate

If so, it's hard for me to believe that the impact will have much effect upon the setting of the anchor, for the tip of the fluke will likely be outside the immediate impact area where breaking up the surface has occurred.

I do agree with your points Jim. I am not convinced the slamming into the seabed has any effect. I raise it only as a possibility.

Perhaps if lots of people try it we can get an idea if the first time setting rate improves for them.

It may be that it has an effect in some substrates like weed and not in others like soft sand. It may be that it has some effect on those anchors like the concave roll bar anchors that set very rapidly and close to the drop point, but not on anchors like convex plow anchors that move many metres before they set. It could also have more of effect on heavier anchors. Or it may have no effect at all.

One drawback I didn't mention is that it makes a hell of a din as the chain rattles out at high speed so if entering an anchorage at night when people may be asleep, it is not the best technique to use.

Most anchors do drop straight down with the fluke amost vertical. They drop any which way usually slightly spinning as they fall. The Mantus is quite different, as it "flies" in a stable upright way with the fluke closer to hoziontal.

If I drop the anchor rapidly, when diving I can often make out the triangular shaped impression of the Mantus fluke where it has hit the seabed. I can sometimes even make out the mark from the bolt heads that stick out under the fluke! These are hard to show clearly in a photograph, but you can see them in this one. (Note this photo was a from a couple of months ago, not our current anchorage)

[malbert73]

Great last pictures. On the Chesapeake I often mock power boaters (sometimes sailboats too) performing the "Olympic anchor toss" with their puny anchors and mass of line.

Maybe they know something? but most of time they don't even back down properly so who knows?


Sent from my iPhone using Cruisers Sailing Forum

[noelex 77]

My mermaid braved the cold for this better photo see post #1247 for my photos from the surface.

[monte]

Unwind the chain, just motor around the anchor in circles a few times. If you want to be really salty you can sail
Btw, what's that anchor alarm app noëlex. The display looks good.

[Group9]

Could you post another photo of the girl setting an anchor? I really don't care which anchor it is or how it performs.

[noelex 77]

Originally Posted by monte

Btw, what's that anchor alarm app noëlex. The display looks good.

It is iDrifter XL. I normally always set my Furuno GP-32 that is next to my bed as an anchor alarm. It is set when we arrive and stays on full time. I have therefore only used the iPad anchor alarm apps out of interest, but the iDrifter seems a good one. The only feature it lacks is the ability to send a text message when the alarm is activated.




If you are looking at apps GPS HD by monition X is worth looking at. It is NOT an anchor alarm, but is very useful when finding out of the way anchorages that are not listed in the pilot books/cruising guides.

With this program you can instantly switch between Google, Bing and Apple satellites images. Often one of these will show more detail than the other. The images are at least from different days so there is sometimes much more bottom detail in one, or the other.
The program also has a great easy to use measuring tool so you can work out the swinging room between various hazards. For example here are the Google and Bing satellite images of the same bay:

[noelex 77]

Back to a mud anchorage and quite a soft one at that. This deep bury was under engine force alone. The fluke and shank have completely disappeared along with much of the roll bar.

The anchor has buried to this depth in a very short distance. Interestingly, the marks show it has done this straight from an upright position.

Most new generation anchors are designed to fall onto their side to set. In hard or medium substrates the only way the anchor can begin to slice through hard ground is to present the knife edge of the fluke with the anchor on its side.

In soft substrates such as very soft sand or mud, the penetration is so easy the anchor will set from an upright position with the anchor sitting flat. I see this a lot in soft powdery sand in Australia. It is very rare here and only starts to occur when we get to soft mud anchorages.

We have been joined by some friends. This is the first cruising boat I have seen for three months. They have a Delta. In this soft mud the Delta will typically bury completely, unlike the photos that I have shown so far of the Delta in harder sand. I would love to get some photos of this, but with poor visibility and no GPS position for their anchor, my long search was fruitless despite the anchor apparently having a large underwater float.

There should be lots more boats out on the water shortly and therefore different anchors to photograph again, as the season is starting soon. It would be nice to see anchors other than mine again.

Anyway, I managed some poor photos from the surface but my mermaid braved the elements for these much better photos:

[noelex 77]

I have been experimenting with techniques to get some better photos from the surface in these mud anchorages with poorer visibility. The first involved putting the camera in movie mode attaching it to tripod (with the legs folded in) and using this as an underwater "spear" fired at the anchor filming all the way (obviously with a safety line). The initial results were very promising. The camera end tends to be a bit buoyant so after a few metres it floats up and spoils the "aim". I think with some trim weight it will work very well. A similar thing could also work well with a GoPro attached to boat hook.

My second idea is suspend the the camera with weights and rope below the dingy so it is a couple of metres off the bottom. I usually have the anchor position well pinpointed on GPS. This is important in crowded anchorages especially in light wind. Your anchor can be off to one side, or even behind you and another boat can unwittingly drop their anchor on top of yours. The initial separation of the boats may look fine, but as the wind picks up the boats will come together. Knowing your exact anchor position is important.

Hopefully with this new filming technique even in very poor visibility I will be able to row around in the tender in the vicinity of the anchor while filming and later extract some still images of the anchor. This should also work in other parts of world where underwater visibility is poor. Come on CF members - let's see some more photos of anchors in the real world!

[Tayana42]

This continues to be one of the best and most informative threads on the forum. Thank you.


S/V B'Shert

[kas_1611]

Noelex, hoping to pick up a waterproof camera before heading back to the boat for this summer so will try to get some pics either of our current Delta or maybe a new Vulcan if I go ahead and buy it this year.

Thanks for all your time and effort in this and to your mermaid for risking the cold

Keiron

[noelex 77]

I have not been able to get a look at the anchor for some time in this mud anchorage. It has been just too murky. Suspending the camera under the tender is a technique that is taking some time to perfect and so far has not produced any good images, but I am still hopeful.

We were set to move a couple of days ago, but were confronted with this forecast. The 49 knots average wind only just qualifies for Storm force, but the 66 knot forecast for the gusts put us off moving from this location that is very protected from the SE.




The latest forecast issued this morning is a bit better, but it always nice to be in the most protected spot even if it's overkill:




We have actually moved location both to get a bit more shelter from the SE and because a very nice local explained that where we were anchored was rock and we needed to move a few hundred metres to get away from it. The locals have often lived on the same island for generations and most fish, so know the waters well. The gentleman concerned spoke no English, but took the trouble to draw an anchor symbol on the ground and pick up a rock to get his point across. One nice thing about cruising in winter is that there are no tourists, so you are treated as a member of the local community.

We have been joined by another boat, a Canadian cruising yacht. They dropped a steel Spade in a very professional manner. It is always interesting to see how boats with different anchors fair in these stronger conditions.

[noelex 77]

The water is very murky. I am still trying to perfect the technique of dangling the camera below the tender to get a glimpse of the anchor and a usable image. This is the only method when nothing is visible from the surface.

I managed this photo just a few minutes ago. Not great, but it at least shows the anchor is very nicely set.

This is a very popular anchorage in summer and the bottom is littered with things like towels that have probably blown off boat rails when they have been hung up to dry. It is always good to get visual conformation the anchor has not hindered by anything when stronger wind is forecast, as it is for tomorrow.