Mantus anchors

[evm1024]

Originally Posted by motion30

i am in south florida, Hollywood just south of ft lauderdale

Shucks, that is just too far to ship (cross country).

Regards

[evm1024]

Originally Posted by SailRedemption

I have a similar size boat (47' 30k dspl) and was going to get an 85lb Mantus. What is making you want something bigger? Does it not do its job well? I found that the 85lb is on the heavy side of our boats compared to Ronca and Manson weight tables. I think the 105lb would be slight overkill considering how effective these anchors are over say the same size CQR.

- Ronnie...on the geaux

The 85 does its job very well on my boat. I was thinking about the 105# for when we load the boat up and start getting close to 40,000#. At that point I think that the 85# would still do great any any storm we would expect to encounter with a 105# adding a bit of overkill and peace of mind.

Plus there would be more laughter when at the dock as people looked at the anchor.

--Regards

[Mantus Anchors]

Originally Posted by OysterDriver

I am in the process of planning a circumnavigation and want to change my main anchor. I currently have a 75lb CQR which was supplied when the yacht was new in 2003. I really like the look of the Mantus anchor and I particularly like the fact they can be taken apart for storage on long ocean passages. The only down side is that the makers recommendation for a 56 foot yacht for all conditions is a 170 lb anchor???
Does anyone have any experience of these anchors and any advice on sizing?

Dear Oyster Driver its Greg with Mantus, I believe our sizing guide recommends a 105 lbs model.


When making sizing recommendations for a working anchor we are generally referring to the needs of a cruising boat spending most of its time on anchor, in doing so we try to envelope high sustained winds (40 kts) and assume poor holding conditions (low viscosity bottoms). Some may think these recommendations to be too conservative especially when compared to sizing tables from other manufacturers. Companies often make claims of superior anchor efficiency, stating that their small anchor X will outperform a much heavier anchor from their competitors and often use sizing charts as a marketing tool to that end, recommending anchors and anchor systems that are dangerously undersized for their intended use. Comparing surface area can be a good judge for potential holding capability. Our anchor sizing recommendations are presented in the table below and we divided in three categories: Lunch Anchor category is recommended for lighter use, expected winds under 25 knots, working anchor for winds under 40 knots and finally, storm anchor recommendations are intended for winds up to 60 knots. These recommendations are made assuming the worse case scenario, a poor holding bottom and thus may seem conservative but we believe are accurate.

[Mantus Anchors]

Originally Posted by Kenomac

'Just saying in my prior post, that several manufacturers offer new generation anchors that work fine without the big roll bar. Spade, Rocna, Ultra etc. I personally dove on our anchor nearly every day last summer, and never once saw it lying on its side or upside down... so why buy an anchor today that's massive in size when compared to the others, plus one would also need to somehow accommodate an enormous hoop on the bow just to get the thing to work properly.

Well, the bottom line is.... it's your money, buy whatever you want. But don't expect to be breaking a 175 pound anchor down when underway and storing it in a locker.... 'not going to happen.

Check Video at time at 2:09, While Ultra and Spade are good anchors that I would recommend to any cruiser we do offer an edge on penetrating hard bottoms.

https://www.youtube.com/watch?v=JNBypaLMXlw

[UNCIVILIZED]

It'd be worth touching base with dockhead on this, given his boat's size, plus the fact that he does a LOT of high latitude & horrific weather type, cruising.

[Factor]

Originally Posted by Mantus Anchors

....
When making sizing recommendations for a working anchor we are generally referring to the needs of a cruising boat spending most of its time on anchor, in doing so we try to envelope high sustained winds (40 kts) and assume poor holding conditions (low viscosity bottoms). Some may think these recommendations to be too conservative especially when compared to sizing tables from other manufacturers. Companies often make claims of superior anchor efficiency, stating that their small anchor X will outperform a much heavier anchor from their competitors and often use sizing charts as a marketing tool to that end, recommending anchors and anchor systems that are dangerously undersized for their intended use. Comparing surface area can be a good judge for potential holding capability. Our anchor sizing recommendations are presented in the table below and we divided in three categories: Lunch Anchor category is recommended for lighter use, expected winds under 25 knots, working anchor for winds under 40 knots and finally, storm anchor recommendations are intended for winds up to 60 knots. These recommendations are made assuming the worse case scenario, a poor holding bottom and thus may seem conservative but we believe are accurate.

Hi Greg

Have you calculated the loads to be on boats of the specified sizes for the lunch, working, and storm wind speeds, and correspondingly, what test data do you have that illustrates that the anchors will hold the boats lengths in those wind speeds, and in low viscosity bottoms?

genuine Question, as many anchor threads are based on opinion and anecdote rather than evidence

[Sailorman Ed]

Greg - I only see one sizing guide based on length and displacement. Any difference for multihulls?
Ed

[Mantus Anchors]

Originally Posted by Factor

Hi Greg

Have you calculated the loads to be on boats of the specified sizes for the lunch, working, and storm wind speeds, and correspondingly, what test data do you have that illustrates that the anchors will hold the boats lengths in those wind speeds, and in low viscosity bottoms?

genuine Question, as many anchor threads are based on opinion and anecdote rather than evidence

I wish the process was more scientific.... but essentially we tested anchors of three different sizes in hard and soft silty bottoms... and compared the data to ABYC table for loads expected on the anchor gear at different wind conditions for different vessel size. Of-course we had to extrapolate for anchor sizes we did not have data for....
Greg

[Mantus Anchors]

Originally Posted by Sailorman Ed

Greg - I only see one sizing guide based on length and displacement. Any difference for multihulls?
Ed

Million dollar question... the usual rule of thumb of-course is to choose an anchor a size bigger than for the same LOW Mono-hull... In reality I can say that very few of our Catamaran customers elect to do this and still report good results after picking their anchor sizing according to the chart. I think this is because one rarely encounters a situation that entails both winds in excess of 40 knots and a seafloor with poor holding.
My personal belief is that sizing up for CAT is still a good idea.
Greg

[Kenomac]

If the need ever arises to anchor our boat on dry hard beach sand.... I'll consider your Mantus anchor. But so far, most of our anchoring has been done on the ocean bottom with the anchor biting into a water saturated substrate... completely different.

[JPA Cate]

To the OP:

"noelex" posted a thread, "Pictures of Anchors Setting...." in which he has posted pics of a very heavy Mantus setting well in difficult bottoms. He probably states, but I don't remember, exactly how heavy it is, nor what his boat displaces, either. You might be interested to read the thread. It's quite long, and probably best absorbed by reading it in 3 or 4 sittings.

Ann

[colemj]

Originally Posted by Mantus Anchors

Million dollar question... the usual rule of thumb of-course is to choose an anchor a size bigger than for the same LOW Mono-hull... In reality I can say that very few of our Catamaran customers elect to do this and still report good results after picking their anchor sizing according to the chart. I think this is because one rarely encounters a situation that entails both winds in excess of 40 knots and a seafloor with poor holding.
My personal belief is that sizing up for CAT is still a good idea.
Greg

Our experience with catamarans at anchor is that the perceived extra windage is not borne out in increased anchor forces in practice. In fact, I think catamarans provide LESS force on anchors than equivalent LOA monos.

Here is my reasoning: The front aspect of a catamaran is its lowest windage aspect. When anchored with a proper bridle, catamarans are rock-steady. They just do not hunt - and provide their lowest-windage aspect to the wind at all times.

Pretty much all monohulls we observe, however, hunt terribly in comparison. Some go broadside to the wind, pull back hard on the rode, tack and head to the other broadside - repeat ad nausem.

While not all are that bad, all of them (we have ever observed) do not steadily and reliably present only their lowest-windage aspect to the wind. They all hunt to some extent and present higher-windage.

As a result, they present variable forces on the anchor system, with some of these forces being snatch loads.

Any back and forth movement of a catamaran from chain catenary is mitigated in force by most catamarans being lighter displacement and the velocity being slow. In contrast, a mono hunting provides not only a larger mass, but a higher velocity.

Never hurts to upsize an anchor, but in practice this may be better advice for many monos than most catamarans.

Having said that, typical production catamarans are now heading toward outrageous weights and windages...

Mark

[SailRedemption]

Originally Posted by Kenomac

If the need ever arises to anchor our boat on dry hard beach sand.... I'll consider your Mantus anchor. But so far, most of our anchoring has been done on the ocean bottom with the anchor biting into a water saturated substrate... completely different.

If he showed you a video of the same test but underwater with a saturated bottom(which they also have), you would still be a naysayer and have an excuse about something. They got anchors right.

The OP asked about Mantus anchors, not to be sold on Ultra anchors. Let it rest already, sheesh.

- Ronnie...on the geaux

[Fortress]

Originally Posted by Mantus Anchors

Companies often make claims of superior anchor efficiency, stating that their small anchor X will outperform a much heavier anchor from their competitors and often use sizing charts as a marketing tool to that end, recommending anchors and anchor systems that are dangerously undersized for their intended use. Comparing surface area can be a good judge for potential holding capability.

Greg,

I don't know if the first sentence above was directed towards us, since with our aluminum-alloy anchors, we have made a strong claim from our inception in 1987 that our much lighter anchors will out-perform heavier steel models in common sand, mud, or clay bottoms.

I agree with your comment about comparing surface area as a judge for potential holding capability. However, as I was lectured by Bob Taylor, the US Navy anchor design expert who consulted for us during the Chesapeake Bay soft mud tests, a key component of anchor performance is the angle that the fluke makes with the seabed during penetration, which he calls the "effective fluke angle."

We saw this firsthand during the Chesapeake Bay tests when we deployed a monstrous non-roll bar, "new generation" anchor, which from its sheer physical size, everyone aboard expected it to be a top performer....but it basically slid along the bottom during almost every pull.

It was obvious that the large surface area was not orienting at an aggressive angle into the soft mud as the anchor was being slowly pulled along.

Brian