Photos of Anchors Setting

[kas_1611]

Lure if you are considering a new generation anchor and are concerned with sizes then I can recommend the Rocna Vulcan as a replacement for a Delta.

We swapped our 16kg Delta for a 33kg Vulcan (yes I know WOW that's huge!) and the shank length of the Vulcan is actually shorter than the Delta. Even the tip of the anchor is a little further away from the gelcoat than before, something I was actually a tiny bit concerned with when I saw the beast in real life for the first time.

One of the considerations that made me go for the Vulcan was actually the lack of the roll bar. We might add a Gennaker pole to our yacht in the near future so we can fly a cruising chute. A roll bar anchor may well have impeded the function of the pole. Plus the fact I'm a massive Star Trek fan meant I had to go with the Vulcan really. If only they'd called it the Klingon

Keiron

[Prairie Chicken]

As Hoppy suggests, viewing a trace of the boat's movements is even better. I have a GPS next to our bed just for this purpose. Kinky .

SWL, now I do have concerns!! I'm not sure what AA would do with an anchoraholic, but it might be fun to watch! Anyhow, could be much worse I suppose.

[Lure_]

Originally Posted by kas_1611

We swapped our 16kg Delta for a 33kg Vulcan (yes I know WOW that's huge!) and the shank length of the Vulcan is actually shorter than the Delta. Even the tip of the anchor is a little further away from the gelcoat than before, something I was actually a tiny bit concerned with when I saw the beast in real life for the first time.

kas_1611, I do not have issue with rollbar, as I fly Parasailor, so no gennaker pole. It is great to hear that Vulcan is further away from gelcoat, as that was my primary concern with new gen anchors. And your Cruiser 40 is similar design as my Vision 42, so there is hope.

I also noticed that you have stayed with 8mm chain, even though that they recommend 10mm - was this due to power of the windlass? I would also prefer to stay on 8mm, but I am concerned if this is than really storm-ready (based on recommendations from anchor vendors).

Since your boat is in Croatia, where did you buy Vulcan? I am transferring my boat from Croatia to Slovenia end of month and am looking for supplier in the region (Slo/Cro/Ita).

I hope that we are not cluttering this great thread with our discussion - we can also move to private messages.

[Seaworthy Lass]

Originally Posted by Prairie Chicken

SWL, now I do have concerns!! I'm not sure what AA would do with an anchoraholic, but it might be fun to watch! Anyhow, could be much worse I suppose.

At least his interests are water based. Mermaids don't cope well on land .

SWL

[noelex 77]

This was a Rocna.

It was not doing well, but this was a truly awful substrate. The dead weed on the bottom was not having much effect, but was obscuring some of the details making the substrate difficult to see. Underlying it was rock with a light covering of powdery sand and loose rock.

The Rocna has just scraped along the bottom coming to rest against a larger rock.

This is another good reason to set the anchor properly. This also acts as a test that the anchor is indeed holding. I doubt this anchor would have held full reverse.

This anchor was only 50m from my Mantus so there were better (although still not good) patches of substrate available.

The other thing you can do is oversize your anchor.

A larger anchor will not set any better than a smaller one, but the larger blade area will give higher levels of grip.

Interestingly, the Rocna owner did snorkel over the anchor and said he felt it was very well set. With the clear water here, a reasonable number of owners inspect their anchor underwater. Unfortunately, they seem to have little idea when the anchor is doing well or poorly.

It is not practical to inspect the anchor in many parts of the world so even experienced sailors can have little idea of what is normal. I hope the photos in this thread give people the information to be able to assess their anchor and seabed accurately. As many of the world's great cruising grounds have warm clear water where inspecting the anchor is easy, it is a handy skill to have.

[noelex 77]

This was the next morning. Overnight the Rocna swivelled 90° with a wind change and dragged about a metre. It did not "shuffle". To do this the anchor needs a reasonable substrate and a reasonable set and this anchor was missing both.

The anchor is looking even worse now, but this is a terrible substrate. There are some bottom types that will defeat any anchor.

[noelex 77]

This was a Delta. It was not doing well, but once again I would caution that this substrate is in many patches very poor. It was also very variable, so even anchors lying quite close together could be in quite a different bottom.

I could not get all the setting distance in one photo, but as you can see the anchor has gone a long way:





In this photo you can see the setting mark is not showing the ideal profile ie not getting progressively deeper as the anchor moves back. It is not even a constant depth, but rather shows patches when the anchor sets a bit deeper only to become shallower again and this cycle is repeated.





The wind was swinging all over the place. Here you can see the chain leading back up to the boat. With shifting wind it is surprising how much time a boat will spend quite close to the anchor. It is worth using the GPS so you know where your anchor is at all times:








Some more photos of this anchor to come.

[noelex 77]

With the wind swirling around, the chain was caught around one of the flukes.

This is generally not a big deal. It will eventually slip out. However, it is another reason why you should try and set the anchor well.

[noelex 77]

This was the Delta the next morning.

The wind had rotated about 90°. Normally the marks in the substrate show what has occurred, but the chain caught around the fluke had scraped away a lot of the evidence.

The anchor had developed a significant list with the rotation, but it still had some grip. Remember this is is a very poor substrate.

[noelex 77]

Please bear in mind this is a terrible substrate. Sorry to keep emphasising this, but I don't want you to judge these anchors too harshly.

This is a reasonably popular anchorage and the take home message is how some anchorages have patches of very poor holding. When anchor sizing tables indicate a recommended size of anchor, they do not have this sort of substrate in mind, but these sort of bottoms do occur.

Get the best anchor in the biggest size you can reasonably manage. Importantly, this protection is then always deployed, unlike multiple anchors. In an anchorage like this dragging at a low windspeed is real possibility. Set an anchor alarm for an extra layer of protection.

This was a Kobra and it was doing very, very poorly 6m @5:1. In fact it was slowly dragging as we watched in less than 15 knots of wind.

This is the start. The anchor had a long setting distance. After the engine was cut the wind swung 130°. The anchor dragged a couple of metres in the new direction. Then the wind swung back roughly the original way and the anchor dragged back another metre. As we watched, the anchor continued slowly dragged back with stronger gusts. It only moved an extra few inches, but this is not a good sign.

This is the drag mark when we arrived at the anchor:

[JPA Cate]

Just so we're clear, this performance is due to poor bottom, not poor anchor, n'est-ce pas?

Ann

[noelex 77]

Originally Posted by Ann T. Cate

Just so we're clear, this performance is due to poor bottom, not poor anchor, n'est-ce pas?

I should have poked and prodded the substrate around the Kobra a bit more. Before I was using the camera I did this whenever there was something irregular, but with the multiple dives needed to get photos I have fallen out of the habit.

This is certainly a very bad substrate. The Kobra will not perform like this in most bottoms.

The Kobra is one of the best convex plow anchors, but the biggest drawback of this style of anchor is that they struggle to generate enough force to penetrate harder substrates. Anchors like the concave roll bar anchors can often seemingly easily penetrate a hard sand layer where a convex plow anchor will just scrape along the hard layer which is usually a few inches below the surface.

The Mantus is superb at penetrating through hard sand. We were anchored only a few boat lengths from the Kobra and the Mantus set within a shank length, although not as well as it usually does. Have a look at the substrate around the Mantus in post #1864 and compare it to the substrate around the Kobra. Here is a reminder:



Would the Mantus have dug in exactly where the Kobra was? A definitive answer is impossible, but no traditional anchor test is ever going to be conducted in difficult substrates like this. Some extrapolation based on the photographic results is all we have.

In medium soft substrates all anchors will do well. Good performance in tough substrates is what separates the excellent anchors from the 'also rans', but some substrates are just impossible for any anchor. Was this substrate impossible, or did the Kobra fail where other designs would have worked?

I will post some close ups of the Kobra in the next post. Those photos show the sand in much greater detail.

[noelex 77]

It was very hard to get clear photos of this Kobra.

The substrate produced clouds of haze just with a little bit of wave action and current, but this anchor was very slowly dragging.

Every time it moved even a fraction there were clouds like this. Fog? :




With a lot of patience I got these photos. They show that the anchor was trying (but not succeeding) to dig in:










These very slow drags are quite common, but are not usually noticed by the skipper. It is surprising how often the owner thinks their anchor has done a good job when in reality it is doing poorly.

The concern is that this was in only in 15 knots of wind. Although I stress once again that is a very poor substrate.

[noelex 77]

This was a Manson Supreme. 6m @5:1. For some reason I have seen few Manson Supreme anchors lately. I see a lot in Australia and even in Europe they were popular in the Ionian and in Croatia, but there have been few in the Aegean.

It is another anchor that I rate as 'excellent' and considering the substrate, it was doing a good job here. It has set with much more heaping up than is normal for this anchor. It has also been left with a significant list, but it has a good solid grip despite the difficult bottom.

[Kenomac]

Sometimes, this is as good as it gets. Set in this manner, our 45kg Ultra has held for three days during steady winds of 20 knots gusting to 25 knots occasionally. I did let out 17:1 scope at one time since I was backed up to within 100 meters of a leeward shore in only 3.5 meters depth. I had an anchor alarm on.

I've watched as many other boats have tried with plow type anchors without success and had to leave. The costs of having a lousy CQR anchor can be quite high, I just finished watching a German couple with a CQR try five times unsuccessfully to set their anchor on both sides of our boat, then decide to motor into the marina defeated. Their crappy anchor will cost then 200 euros tonight.