Anchors, Guns and Strippers!!!!

[noelex 77]

The Mantus anchor has a very long, thin, tapered, stiletto fluke. This makes the anchor a little harder to fit on many bow rollers, but it penetrates weed exceptionally well.

[rslifkin]

Originally Posted by noelex 77

The Mantus anchor has a very long, thin, tapered, stiletto fluke. This makes the anchor a little harder to fit on many bow rollers, but it penetrates weed exceptionally well.

The roll bar on them is also massive, which should reduce the risk of clogging as well.

Unfortunately I can't fit one, as the end of my pulpit is about 19" out from the roller, so even though the pulpit will fit through the roll bar, it would take some serious fussing to get the thing over the end of the pulpit (Mantus says 14.8" max roller to end of pulpit for self launching on a 65lb).

[groundtackle]

Vryhof design dept has just entered the chatroom...

[groundtackle]

Noelex, That's an excellent side view of a Mantus, just measured the angle off the image and got 16 degrees as well.
This thread over on YBW gets into it;

https://forums.ybw.com/index.php?thr...anchor.533534/

[noelex 77]

Groundtackle, I think you have raised one of the big problems with the Excel. The substrates in Australia are very soft. Those lovely soft sand beaches are not just in the brochures, they exist everywhere and this same substrate is generally found on the surrounding seabeds. The most common alternative is soft mud.

The Excel has been developed and optimised for this type of substrate. Unfortunately, with the limited fluke area of this type of design and reduced drag of the convex fluke, the fluke angle needs to kept large.

All of the development and testing of the Excel has been done on the (admittedly fantastic) beaches not far from my house. This is fine for Australia, but does not translate as well to the rest of the world.

If an anchor’s fluke angle is too large for the substrate, the anchor’s holding drops to almost nothing. This is very important to understand. This is just what I do not want from an anchor. The modern trend is not to switch anchors for different substrates, but rather have an anchor design that works reasonably on all bottom types.

I want to drop the anchor and know that no matter what type of substrate (within reason), the anchor will hold. This is why the modern trend is towards concave designs (that inherently provide more drag) together with large fluke areas (that also provide more drag), combined with a smaller fluke angle. The smaller fluke angle ensures the anchor will still set in difficult substrates.

Anchor manufacturers and their representatives have a duty to present their anchor models in the best light, but I think they should refrain from commenting on designs from other manufacturers.

[Lodesman]

Originally Posted by noelex 77

The other issue is that most anchor designs will hold in thick weed quite reliably just by gripping the weed itself, but this only applies in moderate winds. Thus someone who frequently anchors in thick weed can describe his anchor as excellent because it has reliably held the boat in 25-30 knots of wind on numerous occasions. However, to hold in strong wind the anchor typically needs to penetrate the weed and dig into the substrate below.

Outstanding observation, and something we would all do well to be aware of.

[Factor]

Originally Posted by billknny

On the other hand Mantus size tables give three sizes a "lunch hook", and standard size, and a storm anchor. .

I have never understood the concept of a lunch hook, do people really put one anchor on for day sailing or for short stops and then change it to another anchor for "standard" sailing. About the only time I see benefit in a lighter (not smaller) anchor is racing to keep weight off the bow. I do endorse having a second anchor of a different type for those occasions when a different style is more likely to work, I cant carry 20 anchors so I choose a Excel or a Spade and a really big fortress.

Originally Posted by Mike OReilly

Not to take this too far off topic, but the Sarca Excel anchor looks a lot like the old Delta. I hope/assume there are significant differences.

There are - The delta is a plough anchor, the excel is not amongst many other differences.

Is the Excel better?

Yes

Originally Posted by noelex 77

particularly the roll bar designs such as the Mantus and Rocna, set very rapidly

Again never understood this - a roll bar can have no effect on the setting of the anchor other than to get it in the right orientation to set, once it starts to set the roll bar is of no use, in fact on some it is an impediment as it creates a point of resistance. Obtaining orientation doesn't need a roll bar. As spade and sarca have demonstrated.

The anchor is invariably the weak link in the system so anything you can do to improve the anchor’s holding ability will make you more secure.

Almost agree, the skipper is the weakest link. A skipper who is careful and thoughtful will get better anchoring with a old CQR than a dunderhead who just drops and hopes will get with a Mantus or Spade etc.

Originally Posted by noelex 77

Groundtackle, I think you have raised one of the big problems with the Excel. The substrates in Australia are very soft. Those lovely soft sand beaches are not just in the brochures, they exist everywhere and this same substrate is generally found on the surrounding seabeds. The most common alternative is soft mud. .... This is fine for Australia, but does not translate as well to the rest of the world.

Seriously. Australia has (depending on your source) the 5-8th longest coastline in the world. It covers from 10degrees latitude to 43 degrees latitude. It has anchoring areas that are coral reef located, sand mud weed and rock. It has anchoring areas in the Pacific Ocean, Tasman and Coral Seas, Southern Ocean, Indian Ocean, Torres strait etc etc anchoring areas that experience regular winds in the silly end of the spectrum. Not suggesting that Australia is better or any more special, suggesting that it is pretty much similar to the rest of world, outside of above 60 degrees latitude Which is probably why evryone from the Navy, Coastguard and VMR, and commercial operators are using them. To suggest that because Sarca is Australian and that Australia is different to real anchor locations is spurious and well, just wrong.

Rocnas were developed in New Zealand - are you suggesting they are only of use in that country?

There are plenty of good anchors out there. Your skill is as important as the anchor you choose. I wont use a concave roll bar anchor (resetting issues and damage to the bottom) so that leaves me with a choice of Sarca and Spade.

[JPA Cate]

Dear me,

Are you suggesting that noelex's evaluation of Australian anchoring bottoms is incorrect?

I ask because it seemed a reasonable evaluation to me.

Ann

[groundtackle]

Ann, I've personally never been to Australia let alone dropped an anchor down there. I've had enough hard spanks around the Pacific regarding anchoring and other lessons.
Is it funner or just hurt less?
Chris

[Factor]

Originally Posted by JPA Cate

Dear me,

Are you suggesting that noelex's evaluation of Australian anchoring bottoms is incorrect?

I ask because it seemed a reasonable evaluation to me.

Ann

Yep.
He clearly hadn’t anchored in the places I have. Of course he had anchored in many places I haven’t as well.

Fundamentally I saying that suggesting. an anchor developed in Australia is flawed because Australia only had nice sand and soft mud is not only wrong. It’s patently absurd.

Seriously do you think that anchoring in Australia is So very different To the rest of the planet - or to use Nolexes words does not translate to the rest of the world.

[groundtackle]

Thanks very much to you down there from us up here.
Chris, Nick & John.

[Lodesman]

Originally Posted by Factor

Your skill is as important as the anchor you choose. I wont use a concave roll bar anchor (resetting issues and damage to the bottom)

Would you please expand on these points please? How do the concave roll bar anchors damage the bottom more than any other anchor that is designed to dig in? Having not experienced resetting issues (well once, but that was due to other issues - not the fault of the anchor) I want to know what you mean, and if you have some data to back that up?

[Dockhead]

Originally Posted by Lodesman

Would you please expand on these points please? How do the concave roll bar anchors damage the bottom more than any other anchor that is designed to dig in? Having not experienced resetting issues (well once, but that was due to other issues - not the fault of the anchor) I want to know what you mean, and if you have some data to back that up?

Factor can speak for himself, but I can support what he says about ripping up the bottom. Roll bar anchors bring up huge balls of seabed when you raise them -- one of their big disadvantages in my opinion, and one of the reasons why I got rid of my 55kg Rocna.


However in my experience, they reset themselves as well as any, and better than most. Don't know what he means by "resetting issues".

[Mike OReilly]

Originally Posted by Dockhead

Factor can speak for himself, but I can support what he says about ripping up the bottom. Roll bar anchors bring up huge balls of seabed when you raise them -- one of their big disadvantages in my opinion, and one of the reasons why I got rid of my 55kg Rocna.

However in my experience, they reset themselves as well as any, and better than most. Don't know what he means by "resetting issues".

I've experienced the same balling with my Rocna in areas of heavy weeds and/or particularly soft and sticky mud. In these kinds of bottoms the roll bar can become ineffective, and can act as catcher's mitt, collecting bottom material it's dragged along.

In these kinds of bottoms it takes more skill and time to properly set the anchor before digging it in (which is also why I differentiate the setting stage from digging in stage).

I've found my Rocna to be quite good at re-setting, but I haven't conducted any controlled experiments.

[noelex 77]

Originally Posted by Factor

I have never understood the concept of a lunch hook, do people really put one anchor on for day sailing or for short stops and then change it to another anchor for "standard" sailing.

I agree, at least for most cruising boats with a power windlass.

Originally Posted by Factor

Again never understood this - a roll bar can have no effect on the setting of the anchor other than to get it in the right orientation to set, once it starts to set the roll bar is of no use

But this step is critical. A lot of anchors will stay on their side and carry on for long distances in this orientation, especially in difficult substrates.

Originally Posted by Factor

I wont use a concave roll bar anchor (resetting issues and damage to the bottom)

This is really totally the wrong way around, in my view.

The key to avoiding environmental damage from the anchor (the rode is probably more important, but this is a separate issue) is having a model that sets quickly. The concave rollbars anchors are excellent in this regard.

Take a look at the photos below and decide which anchor type, rollbar or convex plow is producing the most disruption to the seabed. Personally I think that only in a very small number of locations is environmental damage a concern, but an anchor that takes a long time to set stands more chance of picking up or becoming caught under debris, old chains etc.

These are just two examples, but are representative of these two different designs.

In terms of “resetting” you don’t want an anchor that “resets”, especially if you want to avoid environmental disruption. You need an anchor that stays buried, engaged with the seabed as it rotates. This results in no movement other than the rotation. I have posted many photos of this.

In all the many nights anchoring and observing the anchor performance, I have never seen my Mantus or previous Rocna break out and “reset”. It has always shuffled around. I don’t think it is impossible for even good anchor designs to break out while rotating, but it must be very rare.

When the anchor shuffles it is more prone to dragging, especially if it is the type of design that develops a high list. If the anchor drags in this situation it will pick up a lot of debris, especially weed. I think often this is blamed as the cause of dragging when it should more correctly be thought of as a side effect of dragging, at least in most cases.