Is a Delta Anchor OK for hardish mud? E.g. Chichester Harbour?

I might mothball the windlass and get 50 mts of 6mm chain to pull up by hand, an easy task for most.

Rope is well worth avoiding, on a small boat, esp with no forward open locker. What do you do? Lug the whole wet issue, anchor and all, back to the lazerette? Detach just the rope each time? Wet anchor rode is not the best companion aft of the foredeck.

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I might mothball the windlass and get 50 mts of 6mm chain to pull up by hand, an easy task for most.

Rope is well worth avoiding, on a small boat, esp with no forward open locker. What do you do? Lug the whole wet issue, anchor and all, back to the lazerette? Detach just the rope each time? Wet anchor rode is not the best companion aft of the foredeck.

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Yes I have been carrying a 10KG Danforth with 10m of 6mm chain and 35m or rope to the bow and back to the lazerette each time. I had to step outside the shroud holding on with one hand and the lugged the whole wet issue in a trug, not ideal Lol! No problem strength wise just bloody awkward and risky of course! Surely rope is lighter and easier to carry.

Thinking 15m of 8mm chain to use the windlass and 40m of rope with a 10KG Rocna. The windlass is designed to work on specified rope also. Looking on YouTube some say a boat length of chain is adequate so hopefully 15m of heavier 8mm chain will suffice especially with strongish tide flows. I would rather over do it than under do it...
 
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It is quite widely accepted ( in some quarters ) that no one anchor type does every job with excellence, and it is also widely accepted ( etc ) that the Rocna is a very high-performing anchor - despite its high cost.

However, testing by SV Panope/Steve uncovers a problem - ROCNA resetting test - and this is picked up and published by John/Attainable Adventure Cruising.....


Real World, Too

That said, given my general scepticism about anchor testing, I probably would not have written on this if it were not for the reports of sudden and inexplicable dragging of Rocna anchors that we have been receiving over the last few years.

Put the two together, and I’m convinced that there’s a real problem with the Rocna, and that concern extends to the Manson Supreme, since it is so close in design and Steve’s testing shows the same failure.

Failure Modality
The most worrying part of this is the failure modality that Steve’s video shows:
The Rocna fails to reset, not because a rock or large piece of debris has fouled the roll bar (as I always assumed), but simply because mud or sand has accumulated on the fluke—something that will happen in pretty much every set.
Or, to put it another way, these anchors set fine when clean, but poorly when even a relatively small amount of mud has stuck to them.

But Not Often
Having said that, I should point out that we have received only about 20 reports in what I’m sure are tens of thousands of successful sets, although, of course, many other failures may have gone unreported.
And, further, an aggressive 180-degree reset is a rare thing in real anchoring—90 degrees, yes (say in a cold front passage), but 180 degrees, not so much, except when anchored in a strong tidal current.
And that’s certainly a rational way to look at this, which I’m sure many people will adopt.

There's more, much more. Accessing it in full would require a subscription to AAC, which I've judged is worth it.

My 'takeaway' from it all is that one should be extra cautious when using a Rocna in spots with reversing fast tidestreams, such as along the outflow channels draining large sea-lakes such as Chichester and Langstone Harbours, and the likes of Truro and Tamar Rivers. But that is only 'the ordinary practice of seamen'.....
 
That would be superb, I could keep the 10m 8mm chain that came with the boat and 15m of rope and extend the rope somehow...

I don't think I'd be alone in recommending you cut off the 'original' 15m. rope and demote that to alongside-mooring duties, then acquiring 40m. or more new rope for your anchor rode. There are many ways it can be reliably attached, and I'd favour a soft eye with antichafe and a quality shackle.

Through-the-deck holes ( navel pipe ) for anchor rodes always seem to give trouble on smallcraft, and I have sealed mine. I now prefer to use netting sacs ( ask Reeves to show his pics ) for rope rodes and long warps. The rope is simply stuffed inside, with the working end tied 'ready' to the tape/cord at the opening. The other end, a spliced loop, exits a small hole in the bottom of the rope-bag and can be dropped over a handy deck cleat to retain it, or have a longer length of rope attached if ever needed.
 
Thanks for the warning Zoidberg, interesting, I have had the same with my Claw and Danforth anchors not setting when I have been lazy and not cleared old mud off. I think the sharp point and spooned shaped scoop is better designed to cope with mud/weed. When you look at the design of anchors the flaws that are written about are pretty obvious. It makes you wonder why it takes 10-20 years to come up with improved versions or why not just get it near to correct years ago. Stones jamming in Danforth style anchors, blunt ends of claws not digging in, points with a triangular shape tip instead of a scoop e.g. Delta versus Rocna.

I do have a couple of those rode bags you mention, very handy. I have jus looked at my windlass, it does not have a pipe going into the chain locker just a two inch hole through the windlass. This may help the fourteen mm rope being fed into the locker, sorry cannot type numbers once again, old IPad playing up. I would like to try it whilst I have it. It is a shame you cannot attach and detach the anchor onto the chain quickly and easily. It would solve a lot of problems and weight up front as well as concern about it being stolen. I will have to store the Rocna onto the pulpit and hope it does not get in the way of the jib. A small claw anchor was tied there previously when racing to meet regulations so hopefully it will be OK. I don,t like them over the bow when you are punching into waves, especially with my submersible style of boat!!

Ask the audience but I am hoping 15m of 8mm chain and the rest 12-14mm rope will be OK and yes I will buy it all new.
 
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Zagato,

I'm not quite sure how you have come to your conclusions - but they are wrong, and are a worry in case others think the same.

A 'sharp point and spooned shaped scoop' may have been designed to cope with weed and mud - but they fail miserably - they collect mud and weed. Rocna and Supreme are the two designs, both with sharp toes and scoop shaped flukes, that AAC removed their recommendations on as result of the increasing numbers of reports they received of failures (dragging). The collection of weed and mud is exascerbated by the roll bar which consolidates and compresses the clogged materials.

I take issue with another of your comments

It makes you wonder why it takes 10-20 years to come up with improved versions or why not just get it near to correct years ago.

Spade was introduced 30 years ago now - there are copies, Rocna, Ultra, Vulcan - whether they offer an improvement - questionable.

Here is an article that tests out the issues with scoop shaped flukes, or some concave anchors - to which you should have free access (without the need for a subscription)

Anchor Resetting Tests - Practical Sailor

Interestingly Geoff, supplier of Knox Anchors, made the comment that the reason behind the split fluke of the Knox is that it was found that with the fluke closed the anchor developed compacted seabed in the fluke such that it performed like a convex fluke - which might explain the enduring success of convex anchors. The slot in the fluke allows the seabed to flow through the fluke and seabed is not retained to compress. The perforations on the Viking anchor appear to produce the same result. I also wonder if this is the reason for the convex addition in the centre of the concave fluke of the new Epsilon (the cover shape pushes the seabed aside as it does on the Kobra or Excel). If Knox, Viking and Epsilon characteristics are to reduce fluke clogging then AAC were on the right track.

Jonathan
 
We had, on a previous boat, a 40lbs genuine Bruce. It was faultless for six years until one day in Osbourne Bay where we stopped for a lunch hook.

After three goes I retrieved it completely, not just clear of the seabed.

It had a round boulder completely blocking the point and flanks jammed between there and the shank!

So, it failed to set, but for a very good reason.

Nothing wrong with the anchor at all.................................
The OP only need a Gen Belgian 10kg Bruce, jobs a goodun
 
The OP only need a Gen Belgian 10kg Bruce, jobs a goodun

I have used a genuine Bruce for many years now, and have found it to be an excellent anchor. However, it does have the ability to find an odd boulder on the seabed, and clutch it to its bosom, destroying its ability to hold. The moral is not to anchor on stony ground, but then you wouldn't do that anyway. ?
 
Several years ago, when I used to frequent Chichester Harbour I often had problems getting my Delta anchor to set. Particularly in mud to the East of East Head, where a skin of soft lubricating mud covers a much denser substrate. So, I invested in a Rocnor anchor, expecting all my problems to be resolved. My first attempts at anchoring with the “new” anchor proved to be a failure as to my chagrin it persisted on skidding across the mud. That was my Damascus moment, when I realised that the blame for my anchoring problems lay at my door, not at that of the anchors. A thorough appraisal and ensuing revision of my technique has transformed my success at anchoring and proven to me that there is no “magic” anchor.
Mike.
Here on the East Coast we have some similar anchorages to the one you describe. I solved the problems of a Delta not setting by changing to a Fortress. The Fortress easily penetrates the upper soft layer and bites into the firmer substrate. If it has been a good blow, it may take a little more effort to break the Fortress out - but I prefer that challenge to uncertain setting.
 
Honestly you really don't need to spend that kind of money, although it sounds like you have worked through a variety of shapes already.

You stated off asking about deltas? I would revert to that if you can, I had a 10kg on a 26footer always set well and is a good anchor for the places you are going to go. I would suggest that using a anchor without any chain is a bit of a folly as the chain helps considerably with setting. Use what you have and don't over think it all.. Otherwise you end up convincing yourself to spend too much cash on another shiny trinket :-)
 
It came with a 5KG Gen Belgium Bruce 10m of 8mm and 15m of rope. Not a bad shout for what he wanted. I am going to use it as a kedge, the Bruce has been my best anchor so far. I am going to sell my new 10KG Danforth, 7 KG Danforth, new CQR, old CQR, and Fortress, and large Grapple hook and Fishermans, all new or used a handle full of times to help fund my Rocna and chain/warp which looks to be £500-£600 ouch! May just get the Rocna this year and use the rode I already have... I have timing gears, engine bay spray etc to but for my old SAAB 96 and a blimmen shower and toilet to sort for the wife Lol!
The genuine Bruce has some unique properties, but it does not work well in small sizes. You will find the Rocna a revelation.

The Rocna is a great anchor. I have had around 1600 nights at anchor using this model and it is an excellent primary anchor.
 
Honestly you really don't need to spend that kind of money, although it sounds like you have worked through a variety of shapes already.

You stated off asking about deltas? I would revert to that if you can, I had a 10kg on a 26footer always set well and is a good anchor for the places you are going to go. I would suggest that using a anchor without any chain is a bit of a folly as the chain helps considerably with setting. Use what you have and don't over think it all.. Otherwise you end up convincing yourself to spend too much cash on another shiny trinket :-)

Hi 'D' you have hit the nail on the head about over thinking everything. I get into such a tiz about all this. I am still going around in circles about blimmen window sealant and rubber silicon, foam tape, butyl products that are not genuine etc it really does work me up into a real basket case stressed state. I wish I was one of those relaxed guys that just uses what he has, an anchor is an anchor, ties a knot instead of worrying about a shackle breaking weight and leaves his sea cocks open all the time. OK they may have to re do things and will have a mishap BUT they are so laid back they don,t worry about it! Funds are limlited but I really want an anchor that will set first time as much as possible so the Rocna it is. Marine Superstore do them cheaper. Hopefully that is not the dodgy company with a similar name that was ripping everyone off ten odd years ago by not sending stuff out people paid for! The chain and rope I will decide on later but folks seem to say at least ten metres chain is ok plus rope, so if I do fifteen of chain then I should be ok. I am only anchoring in Chi Harbour and Newton Creek for god sake as Chubby says. I am afraid I am the result of a past stressful job and just cannot deal with any stress anymore after a breakdown, not even deciding on an anchor. Once you are broken it seems you never return to your old self. I hit a limit and just revert to a curled up ball. My boat is my sanctuary, peace at anchor or on my mooring, I can spend hours without stress in nature ignoring the stresses of real life at home, sorry bit of a tangent there, just going to get a Rocna and get it done.
 
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