Photos of Anchors Setting

[noelex 77]

The boat with the Bugel copy came back to the anchorage yesterday.

This time I did see the drop (in 5m @ 6:1). They dropped and laid out the chain well, but did not put any force on the anchor at all. As there was little wind, I was expecting to see the anchor just on its side and was not disappointed. This is no fault of the anchor. All anchors will look like this if there is no, or very little, setting force.

There is only a very short drag mark. Even the kinked swivel shows there is very little force on the anchor:



Later in the day the wind picked up to about 15 knots plus. This sort of light wind will not have any noticable impact on a set anchor, but if the anchor is unset it is enough force to at least start to set it.

This was the result:



The Bugel copy has done reasonably. It has set in a moderate distance. So far it has not rotated completely level. It will do this with a bit more force, but even the genuine Bugel does take a little longer to rotate level than the concave anchors.

This sort of list does not effect the holding much, with any pull in a straight line the anchor will bury more and level out. The list does reduce the anchor's ability to cope with a change in direction of pull. Rotation one way is fine, but rotation which exacerbates the list increases the risk of the anchor breaking out.
Also bear in mind, the Bugel fluke is reasonably small so it needs to dive down a bit deeper.
Anyway, this is a reasonably good result, but a bit inconclusive until we see the effects of more force.

[bazzer]

IMHO. All of the anchors photographed are good solid anchors. The difference being the setting of them, very poor in some cases and ok in others. Also all of these sets are in very soft beach like sand. Not representative of most other bottom types, ie hard sand,mud, rock etc
But you are giving me food for thought.


Sent from my iPhone using Cruisers Sailing Forum

[noelex 77]

Mermaids love inspecting and caressing anchors

[robert sailor]

Thats actually a pretty good picture

[noelex 77]

Originally Posted by robert sailor

Thats actually a pretty good picture

Thanks. There are several better ones, but they are not suitable for CF publication

[robert sailor]

To me there was some art in the photo, that's what I liked.

[goat]

Originally Posted by noelex 77

Thanks. There are serveral better ones,but they are not suitable for CF publication

You really should let us judge that.

Thanks for all your investigative reporting.


goat

[Robin3]

Originally Posted by robert sailor

Thats actually a pretty good picture

Actually an EXCELLENT pretty picture.

[Jim Cate]

Nolex, the secret to good anchor sets is out: have a beautiful mermaid go down and push them into the sand, as shown in the pic. Now I understand how to do it!

Jim

[Kenomac]

Does one ever really positively know what one's anchor is up to?

Yesterday we pulled into a crowded anchorage, so I decided to anchor just outside in the deeper water with a grassy bottom instead. We dropped our 45kg Ultra and set it confidently by powering back slowly, then letting the 12 knot wind do most of the work so as not to pull it out, then powered back at 1700rpm then 2000rpm. Set perfect, wind changes all day 180 degrees swinging all over the radius... no problem. Or, so we thought.

Went swimming eight hours later and decided to take a look at my awesome anchor completely dug into the weeds. NOT! There it was lying on its side on top of a large flat rock. I guess you never really know for sure unless you take a look. Decided to anchor over by the others in the sand since I plan to leave the boat in place for a few days.

Can I please borrow your mermaid?

Ken

[noelex 77]

Thanks for the story.

2000 rpm and 12 knots of wind would normally have been enough to show that the the anchor was unset and not holding.
However, what sometimes happens is that the chain gets caught under a rock while setting. The trapped chain takes all the setting force. I have seen this happening underwater on several occasions. If the chain slips out from under the rock you are left with an unset, and untested anchor holding the boat.

It should serve as a warning to those that do not use an anchor alarm. One of the purposes of setting the anchor is to test its holding. Many assume, wrongly, that a strong setting force is a guarantee that the anchor is set and holding. Diving and an anchor alarm provide the final level of protection. I usually use both where possible.

PS. I am hanging on to my mermaid, she was tough to catch

[Fuss]

Originally Posted by noelex 77

Thanks for the story.

2000 rpm and 12 knots of wind would normally have been enough to show that the the anchor was unset and not holding.

Ok, but it didn't so it clearly was not pulled back hard enough.

Unless you pull back with at least 75% power and see the bow dip under the strain, then you have not fully set the anchor.

Its that simple.

[noelex 77]

Overnight there was wind in the low 20s. This is not normally quite enough to alter an anchor that has been well set under engine alone. Usually around 25 knots is needed.

However, there was also a slight change in wind direction about 20 degrees, but then with a shift back to the original direction.

I always like looking at anchors during or after there has been some wind, as the wind force will even out the different force skippers have used to set. These were the results:

First the Mantus with no change whatsoever:




Second the Rocna.
This had undergone a slight rotation. It now has a very slight list and some of the shank is exposed. The exposing of the shank is not a problem, as when anchors shuffle around they tend to scrape away the sand from one side of the shank:





Third the Bugel copy.
This has perhaps set a bit better, not surprising as the original setting force was only from the 15 knots of breeze rather than from engine force.
It has rotated a little more level and set slightly deeper, but the change is only small. The weed is just broken strands that collected in the depression left by the drag mark:




For both the Bugel and the Mantus there was some weed close to anchor that was helping keep the pull from the chain in same direction despite the slight change in actual wind direction.
With a bit more wind the chain will start to lift off the bottom all the way to the anchor and this effect will be lost.

[noelex 77]

A (45 foot?) Turkish powerboat joined us in the anchorage with an Ultra anchor.

I have only seen this anchor on few occasions so was interested to see the result.
They dropped to seaward of us, 100m from our anchor. The skipper let out only a small scope. He laid the chain out well, and set the anchor with low revs in reverse, unfortunately the anchor did not hold and they slid slowly backwards until, apparently satisfied , the skipper cut the motor and they ground to halt:




These three photos show the underwater result.
The scope was only 2:1 perhaps 2.5:1 (in 12m of water). This was the major fault preventing the anchor performing well. They also managed to drop just in front of a weed patch, which the anchor fluke picked up on its tip slightly hindering setting.

Photo one shows the drag mark extending over about 7m:




Photo two shows that the anchor has not really set at all with only a very shallow scrape mark. You can see the small amount of weed that has been picked up and dragged along by the tip of fluke:




In photo three the anchor was still moving in the gusts despite the light wind. You can see the puffs of sand kicked up:




Only a few anchors will set at all at 2:1.

I think the only conclusion is that the Ultra did not set (on this occasion) at 2:1 - 2.5:1, a characteristic that it shares with many anchors. It also shows that even an expensive anchor needs basic setting requirements to work, but we all knew that didn't we .

[Kenomac]

Originally Posted by Fuss

Ok, but it didn't so it clearly was not pulled back hard enough.

Unless you pull back with at least 75% power and see the bow dip under the strain, then you have not fully set the anchor.

Its that simple.

It's not that simple. You've obviously not tried to set an anchor in this Med weed/grass. If you power back as you suggest doing, your anchor will quickly pull out choked with a mouthful of weed... then you'll spend the next half hour to an hour extracting the weedball from your anchor and resetting. If done in the same manner as described, you'll provide excellent entertainment for the anchorage residents for the next few hours, up until you get extremely lucky and grab onto a rock. IMHO