Bigger anchor or more chain

Gixer

Gixer

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My first anchor thread, yep I’m in the club.

Now I don’t want to go into anchor types but I have a question.
I have what I would describe as a small anchor well. Comparison charts seem to say a 6kg anchor is adequate for my size of boat but could go up to a 8kg. Would you go for the bigger anchor with 20m of 8mm chain or the smaller 6kg and fit more chain?
The chain will then be connected to a warp.

Thanks
 
Shouldn't the question rather be what set up do I need to safely anchor my boat in the areas that I sail or plan to sail in? Whether or not your anchor locker is big enough is a separate question but some anchor types stow more easily than others, or fit on particular bow rollers better than others, e.g.. I'd also say that bigger isn't necessarily better, personally I'd go with the recommended size of a tried and tested modern anchor and yes you could use 6mm chain by the looks of it...
 
ashtead said:
What advice does your owners forum have ? Maybe this turns on where you plan to anchor but surely a heavier mantus or such like might be the way to go.
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The owners forum is pretty small but most seem to be going for the larger anchor.
Interesting comments on the chain size, it sounds like 6mm is preferable over 8mm.

Think I’ll go for the 8kg, 20m of 6mm chain and 30m of 10mm rope. That should fit snugly.

That was painless, thanks guys! ?
 
If you are thinking of 'upgrading' to a 8kg, CQR, Bruce or Delta - I'd think again.

I'd discount a Mantus, it has the same hold as a Delta and probably costs more - it is demountable. Rocna or Supreme might be a good buy. Kobra has a folding mechanism that might allow you to more easily store. Its a good anchor, and cheap. A number of people on this forum have one (including me). Spade and Excel are going to be expensive.

I'd also suggest you wait till the new Epsilon is released. Its being marketed as Super High Holding Power and cheaply. But its not yet on the shelves. If you want to know about timing ask Jimmy Green. Unless you want to go sailing this weekend, or anytime before April - keep your wallet closed. If weight is going to be an issue then an aluminium anchor, which economically limits you to Fortress or a Viking, which is lighter but not smaller because it is made from high tensile steel. is another option. Both the Fortress and Viking are demountable - but personally I'd keep them assembled in an aft locker (they are not difficult to carry). Both the Fortress and Viking are good anchors, the Viking is much more versatile.

Jonathan
 
I'd be surprised if you can tell the difference between a 6kg and 8kg anchor of the same design. If you are changing design - then you might tell the difference, depends on the existing and whatever you choose as the new design.

Jonathan
 
Neeves said:
I'd be surprised if you can tell the difference between a 6kg and 8kg anchor of the same design. If you are changing design - then you might tell the difference, depends on the existing and whatever you choose as the new design.

Jonathan
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In terms of seabed penetration and holding there can be but marginal difference in adding 2kg to the anchor weight. But you have loading capacity constraints, it seems, so I suggest you consider the catenary profile first. Imagine the achor under strain of a strong breeze, will the drag be sufficient to lift the cable right off the seabed, placing the whole anchoring effort on the anchor? This is to be avoided.

You can mitigate this by letting out 5 times the depth in chain etc or, apply a weight (chum) to the chain, lowered close to the anchor, to keep the pull on the anchor horizontal.

When you review your options, it may be you stick with your current gear but source a chum for those tougher occasions when you want to increase anchor resistance.

Hope that helps.

PWG
 
Interesting comment Peter,

This is why I asked the original question about heavier anchor or more chain. I've taken on board your comment about the Chum.

Thanks
 
peter gibbs said:
In terms of seabed penetration and holding there can be but marginal difference in adding 2kg to the anchor weight. But you have loading capacity constraints, it seems, so I suggest you consider the catenary profile first. Imagine the achor under strain of a strong breeze, will the drag be sufficient to lift the cable right off the seabed, placing the whole anchoring effort on the anchor? This is to be avoided.

You can mitigate this by letting out 5 times the depth in chain etc or, apply a weight (chum) to the chain, lowered close to the anchor, to keep the pull on the anchor horizontal.

When you review your options, it may be you stick with your current gear but source a chum for those tougher occasions when you want to increase anchor resistance.

Hope that helps.

PWG
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With 20 knots of wind my rode doesn't have any noticeable catenary. I now only use a chum / angel to try and the bows swinging around when anchoring in deeper water.
 
Boathook said:
With 20 knots of wind my rode doesn't have any noticeable catenary. I now only use a chum / angel to try and the bows swinging around when anchoring in deeper water.
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Most modern anchors will perform satisfactory at short scope. When we set, Fortress, Spade Excel we set at a 3:1 scope. If the anchor does not set - then it has been fouled and we move on. Once the anchor has engaged and has set sufficient to know it has not been fouled we then deploy the appropriate amount of chain, say to 5:1 and power set. When power setting (which is possibly equivalent to a tension at 30 knot of wind, the rode is as good as straight and the anchor continues to set. We use 6mm chain on a 38' 7t cat. I'm not suggesting it as a sensible practice but a modern anchor will set at 2:1 and will continue to set , more deeply, until the tension balances the hold.

If you are anchoring at a small scope and/or are using lighter chain - then you will need to use a snubber - boat length minimum length and not too beefy - or it will not stretch.

The art of snubbing, in the nicest possible way - MySailing.com.au

The major advantage of catenary with a modern anchor is not that it produces that horizontal tension but that it gives a cushioning to snatch loads - a snubber will do this more than adequately - and a snubber is not ballast and easier to deploy than a chum. Its the 21st Century embrace 21st century ideas!

This idea of using a chum is an anachronism that has no place on a modern yacht, with an intelligent skipper and a modern anchor, Spade, Excel, Supreme, Kobra, Rocna, Viking (not Mantus, M1 - it sets, very, shallow and will benefit greatly from a horizontal rode). I cannot comment on Vulcan nor M2 - whereas I have used the others, I have not used these 2). A Mantus M1 sets at an angle of 16 degrees modern anchors set at 30 degrees - guess which one set deeply and quickly. Guess which one is more secure with some part of the tension imposed in the 'vertical'.

A chum has the same effect, roughly, as its weight in chain. If you think of carrying a chum - you are better off with the extra chain. Many people will carry a spare rode, some chain and rope (we have 15m of 6mm and 40m of 3ply 12mm nylon). If you want a chum then bundle the extra chain up you carry (tie it all together) and use that as a chum. carrying a lump of ballast around as a keel has a necessary usefulness, carrying a 10kg weight in the bow for the occasional time it might be useful seems - well ....daft. If you are hand deploying then add the extra chain as extra length it will increase catenary. Carrying a spare rode lets you set a second ancho in a 'V' which will quell yawing (caused by poor balance in the yacht or derived from wind shear).

Jonathan
 
Just remember that a bigger anchor will have the exact same hold as a smaller anchor (unless the smaller anchor is stupidly undersized). The hold of the anchor is developed by the tension in the rode and that is developed by your engine or windage. Your engine and windage develop the tension and the hold is THAT tension, no more no less. There is a 'possibilie' argument that a smaller anchor will set more deeply than a bigger one (though as I mentioned I doubt you will see the difference between 6kg and 8kg (of the same design) and setting deeply might be more secure.

Gixer - you never said (or I've forgotten) why you wanted a bigger anchor in the first place. I'm not convinced you will be safer but the idea of size does give some people comfort. You might be altruistic and want to support anchor makers - who can tell. You must have some good reason to go and shell out hard earned cash and maybe instead of a bigger anchor you just need another but different anchor - better suited to where you anchor.

Jonathan
 
In the UK (and possibly Oz) we use the word hoover to mean a vacuum cleaner - its a generic name. We call an insulated vessel to store liquid nitrogen a 'Dewar' flask (Jimmy Dewar and I went to the same school). Sir James Dewar developed the technology (or put the technology together to 'invent' the insulated flask. Others might call a similar devise a Thermos (another, now, generic term). If I ask for a thermos - everyone knows what I mean (in the UK and Oz). I call a device like pliers a Mole wrench, everyone I know knows exactly what I mean, There is an anchor called an Admiralty pattern - most know what I mean though most of the anchors have strayed quite a long way from the Admiralty pattern. We all call Dyneema, dyneema - another generic term. Everyone knows what is meant - even though its a brand name - which I think you would also use (even though it the fibre might be made by someone else - other than the owners of the name, DCM).

As long as we understand what a Chum, Angel, Nylon, Dyneema is - it does not matter. And I don't think you can expect any conformity nor try to 'legislate'.

It is also too easy to misunderstand - American seem to call dropping a second anchor so that it hangs off the bow and simply drags on the seabed - a Hammerlock. Its not a term I'm familiar with in the UK (or Oz) and if I mentioned a hammerlock most would think I means some sort of fancy shackle device (if they even knew that). Some terms need explaining - and are not necessarily easily understood.

I try to call a Spade a Spade. :)

Jonathan

Others would include Dacron, GPS.........Aspirin (which is certainly less of a mouthful that acetyl salicylic acid and easier to recognise that ASA), not to mention Paracetamol (or APAP). If I was working with a group of Brits on a yacht and asked someone to pass me the Black and Decker - I would get a hand electric drill - even if it was made by Makita but the sander would be called a sander - even if it was made by Black and Decker?
 
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Neeves said:
Gixer - you never said (or I've forgotten) why you wanted a bigger anchor in the first place. I'm not convinced you will be safer but the idea of size does give some people comfort. You might be altruistic and want to support anchor makers - who can tell. You must have some good reason to go and shell out hard earned cash and maybe instead of a bigger anchor you just need another but different anchor - better suited to where you anchor.
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Thanks Jonathan,

I'm going to replace my rusty chain and old warp which came with the boat, I have no idea of its age so it seems sensible to start again. The anchor is a CQR which looks ok but am thinking of replacing the lot with new. Its not so much about a bigger anchor than making the best use of the weight (anchor v chain) and the size of the locker.

Being honest I haven't used my boat for many years (personal reasons) and am slowly going through a major refit before going back in. At the moment I see the anchor as a safety device in case of engine failure. There's not many places to anchor overnight around my way so I'd be surprised if I do this in the short term.
 
Neeves said:
It is also too easy to misunderstand - American seem to call dropping a second anchor so that it hangs off the bow and simply drags on the seabed - a Hammerlock. Its not a term I'm familiar with in the UK (or Oz) and if I mentioned a hammerlock most would think I means some sort of fancy shackle device (if they even knew that). Some terms need explaining - and are not necessarily easily understood.

I try to call a Spade a Spade. :)

Jonathan
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I thought that hammerlock in the UK was when air was trapped in a water pipe and rapid opening and closing of a tap gave a banging noise but then Collins dictionary says that it is a wrestling hold (UK & USA) and no mention of water pipes ! Possibly I'm thinking of "hammer-knock".
 
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