Cruisers Forum
 


Join CruisersForum Today

Reply
 
Thread Tools Rate Thread Display Modes
Old 06-03-2014, 14:32   #16
Registered User

Join Date: Dec 2013
Location: St. Louis
Boat: 1983 oday 22'
Posts: 661
Re: Anchor

Quote:
Originally Posted by Revelations View Post
All the cats that I have seen do have bridles and I have seen plenty of them.
See.. I learn something everyday here.. I'm glad I asked.
__________________

__________________
scarlet is offline   Reply With Quote
Old 06-03-2014, 16:58   #17
Registered User
 
tomfl's Avatar

Join Date: Apr 2012
Location: Florida
Boat: Seawind 1000xl
Posts: 1,959
Images: 10
Re: Anchor

Quote:
Originally Posted by scarlet View Post
Do all Cats have that kind of configuration? I guess I never noticed it until I looked at Antares.
Just not everyone agrees on the best anchor or size of that anchor, not everyone agrees about what I will call bridle configuration. To make things even more complicated when I am on the ball at Boot Key there are restrictions on how long a bridle can be.

Depending on the direction of wind, waves, and current some folks do not use equal length sides on the bridle, instead altering how the bow of the boat is oriented.

Another thing to consider is some folks will attach something like a small mushroom anchor to the chain of the big anchor to make the pull the chain exerts on the anchor more of a straight line, sorta like what you call the lower center of pull.

To address the OP's question most boats of your size carry at least two significant anchors along with one more smaller anchors for things like stern anchoring. I have a Manson Supreme and a real Bruce mounted forward for quick use, a Danforth (thinking about getting a Fortress) for stern anchoring aft, and two smaller Danforths for what I will call storm anchoring with multiple anchors.

YMMV
__________________

__________________
tomfl is offline   Reply With Quote
Old 07-03-2014, 05:05   #18
Registered User

Join Date: Oct 2012
Location: Home for a couple of years.
Boat: Beneteau 49
Posts: 246
Re: Anchor

Our Lagoon 450 came with a 25kg Delta and about 65 meters of 12mm chain. I replaced the anchor with a 36kg Manson Supreme and added 45 more meters of chain.

We are planning to sail S. Pacific where anchorages are deep, and may have coral, and want to sleep better at night.
__________________
boom23 is offline   Reply With Quote
Old 07-03-2014, 13:42   #19
Registered User
 
tomfl's Avatar

Join Date: Apr 2012
Location: Florida
Boat: Seawind 1000xl
Posts: 1,959
Images: 10
Re: Anchor

Quote:
Originally Posted by boom23 View Post
Our Lagoon 450 came with a 25kg Delta and about 65 meters of 12mm chain. I replaced the anchor with a 36kg Manson Supreme and added 45 more meters of chain.

We are planning to sail S. Pacific where anchorages are deep, and may have coral, and want to sleep better at night.
Have to wonder how much over three hundred feet of chain weigh and how you store it and if you store it close to the bow does it make hobby horsing worse.

All kidding aside that is a lot of weight, but depending on where you are anchoring the extra weight may be justified if the anchorage is very deep.

Another consideration is the bottom. I have a Manson Supreme as my main hook, but also have a Bruce that has proven to hold in conditions where the Manson drags, and vice versa.

Where you are anchoring is an important consideration in selecting your ground tackle. You should take into account the anchor, chain, rode, snubber, and the hardware that connects them. The ground tackle is only as strong as it's weakest link.
__________________
tomfl is offline   Reply With Quote
Old 07-03-2014, 16:29   #20
Senior Cruiser
 
StuM's Avatar

Cruisers Forum Supporter

Join Date: Nov 2013
Location: Port Moresby,Papua New Guinea
Boat: FP Belize Maestro 43
Posts: 6,712
Re: Anchor

> Have to wonder how much over three hundred feet of chain weigh

Over 400kg for 110m of shortlink galvanized 1/2in (13mm)
__________________
StuM is online now   Reply With Quote
Old 09-03-2014, 16:53   #21
D&D
Marine Service Provider
 
D&D's Avatar

Cruisers Forum Supporter

Join Date: Nov 2008
Location: Blue Mountains, Australia
Boat: now working Syd Harbour charters
Posts: 1,459
Re: Anchor

Back to the OP, our experience (FWIW!) seems relevant. We carry the factory installed 25kg Delta with ~80m of 12mm chain. Over now ~20,000nm cruising we dragged (while in the process of setting the anchor) perhaps a few times, probably due to either mud or seaweed on the sea floor, but once bitten our anchor always held, including in some very windy and wavy situations. So our experience very much confirms the Lloyd's High Holding Power rating for the Delta.

According to Lewmar (the Delta manufacturer, of course) the 25kg Delta is spec'd as appropriate for vessels 55-60'. The higher windage of cats may suggest some lower range of vessel lengths -- hence (perhaps?) its selection by Lagoon for our 44' vessel -- altho cats also tend to be much lighter than equivalent length mono's.

Lewmar's recommended chain size for the 25kg Delta is 10mm. Again, however, we are very happy that Lagoon over-spec'd on our vessel in this area as well.

We might also note our practice (perhaps shared by MANY others!? ) of letting out an abundance of chain in any given situation...and then more again when we're in an exposed anchorage. A great sailor friend with hundreds of thousands of sea miles once remarked "anchor chain sitting in your locker isn't doing you any good at all"! That said, we should also note that we have never felt the need for more than (or even all of) our 80m chain.
__________________
D&D is offline   Reply With Quote
Old 09-03-2014, 20:47   #22
Elvish meaning 'Far-Wanderer'
 
Palarran's Avatar

Cruisers Forum Supporter

Join Date: Jan 2008
Location: Me - Michigan / Boat - Tenerife
Boat: 56' Fountaine Pajot Marquises
Posts: 2,641
Re: Anchor

Quote:
Originally Posted by D&D View Post
Back to the OP, our experience (FWIW!) seems relevant. We carry the factory installed 25kg Delta with ~80m of 12mm chain. Over now ~20,000nm cruising we dragged (while in the process of setting the anchor) perhaps a few times, probably due to either mud or seaweed on the sea floor, but once bitten our anchor always held, including in some very windy and wavy situations. So our experience very much confirms the Lloyd's High Holding Power rating for the Delta.

According to Lewmar (the Delta manufacturer, of course) the 25kg Delta is spec'd as appropriate for vessels 55-60'. The higher windage of cats may suggest some lower range of vessel lengths -- hence (perhaps?) its selection by Lagoon for our 44' vessel -- altho cats also tend to be much lighter than equivalent length mono's.

Lewmar's recommended chain size for the 25kg Delta is 10mm. Again, however, we are very happy that Lagoon over-spec'd on our vessel in this area as well.

We might also note our practice (perhaps shared by MANY others!? ) of letting out an abundance of chain in any given situation...and then more again when we're in an exposed anchorage. A great sailor friend with hundreds of thousands of sea miles once remarked "anchor chain sitting in your locker isn't doing you any good at all"! That said, we should also note that we have never felt the need for more than (or even all of) our 80m chain.
That's a really good post D&D. I can't imagine that a 25 wouldn't hold the Leopard 46 in almost all conditions but obviously many here are quite skeptical.
__________________
Not all who wander are lost

http://www.sailblogs.com/member/palarran/
Palarran is offline   Reply With Quote
Old 09-03-2014, 20:49   #23
Registered User

Join Date: Dec 2013
Location: St. Louis
Boat: 1983 oday 22'
Posts: 661
Re: Anchor

I'm really enjoying following this thread. it's very educational... I have 2 questions:

(a) how is it physically possible that a 25KG (approx 55lb) anchor can hold a 15+ ton vessel.. such as the Lagoon 450??!?!?! seriously?! it just boggles the mind how something so tiny can anchor something sooo big!

(b) If it is important to keep the front of the cat light.. then why do they put the anchor on the front? wouldn't it make more sense to have it on the back end?

Thanks for you patience while I'm learning..
__________________
scarlet is offline   Reply With Quote
Old 09-03-2014, 21:14   #24
Elvish meaning 'Far-Wanderer'
 
Palarran's Avatar

Cruisers Forum Supporter

Join Date: Jan 2008
Location: Me - Michigan / Boat - Tenerife
Boat: 56' Fountaine Pajot Marquises
Posts: 2,641
Re: Anchor

Scarlet, if that blows your mind you should read my first post because that little 25kg anchor held my 25 ton boat for 11 years. It just depends on the bottom conditions. Thick sand and mud hold really well, weed and pebbles don't. You will figure it out when you actually go sailing.

Almost all cats have the chain stored in a locker next to the mast, so it's not all the way forward. And no, it wouldn't make sense to have it in the back.
__________________
Not all who wander are lost

http://www.sailblogs.com/member/palarran/
Palarran is offline   Reply With Quote
Old 10-03-2014, 04:12   #25
Registered User
 
mark_morwood's Avatar

Join Date: Jan 2007
Location: Cruising (Atlantic -> Med -> Carib -> Pacific)
Boat: Vancouver 36, Hobie 33, Catana 48, now all with new owners
Posts: 205
Re: Anchor

Scarlet,

If you want to get a better feel for how an anchor works, try looking at some videos of anchor testing. Many vendors have them on their website. The link I have to hand is to the Rocna videos as our main anchor is a 33kg Rocna on 200' 3/8" HT chain + 200' rope. This is on a Catana 48 as a comparison point for the OP.

Testing & Demo Videos | Rocna Anchors // Rock Solid

There are many reasons to not anchor by the stern, though there is a small community who do it. A major reason is that the boat is set up to take weather from the bow, not from the stern, so everything is much more comfortable and secure if you keep the boat facing in to the wind.

Mark.
__________________
mark_morwood is offline   Reply With Quote
Old 10-03-2014, 14:53   #26
Registered User

Join Date: Jun 2007
Location: SW Florida
Boat: FP Belize, 43' - Dot Dun
Posts: 3,425
Re: Anchor

Quote:
Originally Posted by leopard46 View Post
Thinking of using a Delta 25kg anchor with 10mm chain as a primary anchor on our 2008 Leopard 46 11/12 tonne sailing cat. Has anyone used this anchor on a similar sized cat?
I used the 20kg Delta for several years without a problem. Held in a 55kt blow in a wide open anchorage as I watched several other boats drag all over the place. The 20kg got flaking big pieces of rust, replaced it with a 25kg, it works wonderfully. I carry 60m of 10mm BBB, very seldom put out more than 35m, I consider the bridle ~20'. The anchorages I frequent are shallow compared to other places, 30' is about the deepest we general visit. I figure my boat as 10t moderately loaded.
__________________
DotDun is offline   Reply With Quote
Old 10-03-2014, 16:15   #27
Registered User

Join Date: Jan 2014
Location: Sydney, NSW
Posts: 680
Re: Anchor

Mark M,

Interesting link to Rocna testing versus other anchors but it raised some questions about the rigor & validity of the testing in my mind, so I went to Rocna site to request info on anchor testing results and the only contact is a Canadian Metals company & Chinese company. And on the Canadian enquiry form no mention of Rocna at all.

In fact on the Rocna site I did not see any independant testing results shown at all, nor any reports. It may be just a failure of marketing, but certainly doesn't inspire me with confidence.
__________________
BigBeakie is offline   Reply With Quote
Old 10-03-2014, 16:30   #28
Registered User

Join Date: Feb 2012
Posts: 2,441
Re: Anchor

Quote:
Originally Posted by tomfl View Post

.....
Another consideration is the bottom. I have a Manson Supreme as my main hook, but also have a Bruce that has proven to hold in conditions where the Manson drags, and vice versa.
......
I'd be interested to know the respective weights of the two anchors, and whether you've found a pattern to the types of bottom each prefers?

TIA
__________________
Andrew Troup is offline   Reply With Quote
Old 10-03-2014, 17:32   #29
Registered User

Join Date: Feb 2012
Posts: 2,441
Anchor Tests, and why I think they have muddied the waters

Just a word about anchor tests: (or a short book, possibly :-o)

Given that NewGen anchors are "designed to the test", I think the implications of what I'm going to try and set out here might be quite broad-ranging.
These implications potentially affect a wider sector of interest than just those who pay attention to anchor test results.

There are a couple of wee problems, to my mind.

In order to come up with meaningful and repeatable figures, certain simplifying assumptions are made, or procedures adopted:

1) Anchors are tested in a homogeneous bottom (one which produces consistent holding regardless of location or direction of pull)

2) All anchors are set and loaded in identical fashion, at a constant angle (both scopewise, and in terms of compass direction) and constant retrieval rate.

3) The tendency in presenting (or assessing) the data is to highlight the "winner" as being the anchor which developed the highest holding figure.


There are consequences to each of these.

1) As it happens, bottoms like this are also (in most cases) "good holding".

Given that an anchor which is big enough to hold a given boat in "bad holding" will not drag in "good holding", a wide-ranging sailor doesn't really need to consider how well an anchor will hold in good holding (which implies that tests are not much use to such a sailor)

Bottoms which offer bad holding include kelp/grass; rocky/bouldery; and coral heads interspersed with patches of shallow sand. Such bottoms are also notoriously inconsistent, hence completely useless for anchor testing.

Some anchors hold very well in good holding, and very poorly in bad holding. These do exceptionally well in anchor tests.

Other anchors (most notably, the fisherman) are virtually the opposite. It never holds particularly well, but it holds as well if not better in most types of bad holding as in good. The fisherman doesn't even do well enough in tests to be worth testing, but some sailors whose territory is largely bad holding still find room for one of these anchors of last resort. Generally, a big one.


2) A minor problem is that this procedure puts a premium on anchors which are not fussy about how they are set. It also arbitrarily favours anchors (even 'fussy' anchors) which happen to set well under the conditions chosen for that particular test. However some 'fussy' anchors may have unique attributes and virtues which may make them worthy of consideration, just as we might select a life-partner who requires careful handling, but repays it in spades, hearts and trumps.

More importantly: Two key things which (in practice) tend work an anchor out of the bottom prematurely (unless moored to several anchors) are variations in angle of pull, both vertically and (especially, for some designs) horizontally.

Different anchors vary greatly in how well they handle this. The Bulwagga is a design which is inherently highly resistant to both, and the Danforth pattern to a lesser degree (at least in terms of horizontal variations: it has broad tolerance for vertical variations) while the CQR could be expected to resist horizontal variations better than vertical (which you would expect would make it more fussy about catenary, which seems to be borne out in practice: it has problems in shallow bottoms, or with light chain)
The horizontal variations are imposed to varying degrees: some boats sail about incessantly at anchor, and some anchorages have a tendency to fire "bullets" of wind from various directions.
But I don't recall seeing a meaningful attempt to address this in anchor tests.

Think about trying to extract a nail from a piece of timber, or a wisdom tooth from a strongly holding gum. The difference between the force it takes to "worry" it out, versus a brute-force, straight line heave, is considerable. And it's not (to my way of thinking) sensible to assume there will be a constant proportion between the 'worry' and the 'brute' force readings, for a given design of nail, or of tooth, across a range of substrates.

But that assumption, it seems to me, is implicit in anchor testing.

The third key thing is to do with variations in quantum of loading. It's rare for an anchor to see a constant loading in the real-world conditions which pull anchors out: It can happen, if you're anchored just inside a breakwater or spit to windward, but in most situations high winds generate waves which modify the loading on the anchor. Anchor tests cannot affordably model cyclical, let alone irregular loading, realistically, so they do not model it at all.

And, like economists, anchor testers immediately forget the simplifying assumptions they have been forced to make, and draw conclusions for the real world which bear scant relationship to real-world cause and effect.


3) What interests me about an anchor is similar to what interests me about a weather forecast, when I'm contemplating a challenging sail.
I'm not interested in how GOOD the weather might be, at best; I want to know how bad it might get at worst.

My favoured anchor will be the one whose holding is the least crappy, in the crappiest of crappy circumstances. Not a show-pony, but a hard-bitten mule.
__________________
Andrew Troup is offline   Reply With Quote
Old 10-03-2014, 17:44   #30
Senior Cruiser
 
StuM's Avatar

Cruisers Forum Supporter

Join Date: Nov 2013
Location: Port Moresby,Papua New Guinea
Boat: FP Belize Maestro 43
Posts: 6,712
Re: Anchor Tests, and why I think they have muddied the waters

Quote:
Originally Posted by Andrew Troup View Post
Just a word about anchor tests: (or a short book, possibly :-o)

...snip...

My favoured anchor will be the one whose holding is the least crappy, in the crappiest of crappy circumstances. Not a show-pony, but a hard-bitten mule.

Yep, IMNSHO, you've nailed it
__________________

__________________
StuM is online now   Reply With Quote
Reply

Tags
anchor

Thread Tools
Display Modes Rate This Thread
Rate This Thread:

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are Off
Pingbacks are Off
Refbacks are Off




Copyright 2002- Social Knowledge, LLC All Rights Reserved.

All times are GMT -7. The time now is 15:56.


Google+
Powered by vBulletin® Version 3.8.8 Beta 1
Copyright ©2000 - 2017, vBulletin Solutions, Inc.
Social Knowledge Networks
Powered by vBulletin® Version 3.8.8 Beta 1
Copyright ©2000 - 2017, vBulletin Solutions, Inc.

ShowCase vBulletin Plugins by Drive Thru Online, Inc.