Extending anchor chain with warp

[kashurst]

Yup got the standard Delta…. ! Got quite a few improvements and upgrades to do that are higher up the list than changing out the anchor. Mind you, if I’m doing the chain anyway, then maybe now’s the time…?

I thought that then got a £12K bill for two new props, shafts, a bent rudder and some other odds and sods. Fortunately the insurance paid out but the idiot surveyor they sent out delayed the repairs so wasted a long summer. I wasn't onboard at the time, taken the dog ashore in a dinghy. Anchor dragged and onboard crew paniced. That particular boat was used in the med so it's often easy to go and find the anchor and check what it is doing (or not!) as per Hurricane's post. After that episode I always did. After that I bought a ROCNA, later bought a smaller boat and the first thing i changed was the anchor to another ROCNA. They seem to dig in really easily in anything (except rocks) and always end up the right way up with a little tug on the chain. Other similar anchors are available.

I suspect if a delta is really big it will work but at under 25Kg I found they tend to lay on their sides and often don't dig in. I found if you reverse a bit they don't roll over onto the base, they just slide about. If they do dig in in softer materials, they just plough the bottom. In sand or gravel if you put the engines just into reverse, you will just keep going backwards. If there is any weed they just skate over the top. I tested a 25Kg ROCNA in sea grass on a T50. Put both engines into reverse and the chain went tight like a bow string pretty much immediately. Two D9s at 1200 rpm and it still wasn't going anywhere. Went and had a look with a snorkel and it was completely buried out of sight.

I wouldn't trust a Delta to hold the fridge door open.
If you plan on doing proper anchoring have a serious think about it. Loads of Youtube videos showing what various anchor designs really do.

 

[Sticky Fingers]

Point taken. The recommendation from Rocna for my boat is the 33kg, which is about £1800 which tbh is more than enough. I’ve only anchored a couple of times in this boat so far, no problems noted at all it seemed to dig in fine (Osborne Bay in the Solent and Chichester harbour East Head), so it’s early days. I’ll do some tests next time.

 

[MapisM]

The Delta is a ploughing anchor - it just keeps on ploughing.

Based on 7 seasons experience with the current boat (17m and almost 30T) and her Delta 25Kg, I tend to agree.
OTOH, as you might remember, my previous similarly sized even if very different boat, with her two pocket anchors as close to bricks as anchors can be, never prevented me to sleep like a baby.
I mean, at the end of the day, the three factors that really matters when overnighting at anchor are conditions, conditions, and conditions.
Whenever they are bad enough to make any properly sized anchor with a lot of chain insufficient to hold the boat, moving elsewhere and be more choosy next time is the best solution - much better than replacing the anchor.

there are better anchors than Rocna but IMHO, the Rocna is the best "bang for buck".

I can't for the life of me remember, had you already upgraded to the Rocna that day when we anchored together in Caletta, and you struggled to make your anchor set while my brick-alike one did its job right away?
I guess/hope not, because otherwise the Rocna would have been very disappointing!
Anyhow, having said what I just said above ref. anchors being imho overrated in general, I recently toyed with the idea of replacing my Delta, mostly because it's been a while since I threw some money at useless boat upgrades, so I was missing an itch to scratch, so to speak!
The models I considered were Rocna, Mantus and Viking.
And based on what I read, I would tend to say that in terms of bang for buck the latter is even better than Rocna - though that's just an armchair opinion, albeit somewhat educated.
Particularly for the Mk2 Rocna (which looks much better designed and built than the original, hence more worth considering today), if there's one thing that can't be said is that it's good value!

 

[roa312]

The models I considered were Rocna, Mantus and Viking.
And based on what I read, I would tend to say that in terms of bang for buck the latter is even better than Rocna - though that's just an armchair opinion, albeit somewhat educated.

Maybe your research was partly based on the anchor reviews by SV Panope, where the Viking scored quite high in both the 20 lb and 45 lb categories (see below)?
The Viking anchors perform impressively in his tests and also appear to be reasonably priced. However, I find it a bit odd to have to assemble and screw together an anchor, and I would worry about corrosion over time where the parts meet, as well as in the holes in the blade. SV Panope also pointed out that the roll bars on the Viking anchor are quite thin and may be prone to bending. I would definitely be interested in learning about long-term reviews if we have any owners here on the forum,

 

[Hurricane]

I can't for the life of me remember, had you already upgraded to the Rocna that day when we anchored together in Caletta, and you struggled to make your anchor set while my brick-alike one did its job right away?
I guess/hope not, because otherwise the Rocna would have been very disappointing!

It was the Delta and I was VERY embarrassed.
If you remember, I tried about 6 times to get it to hold.
When it eventually did hold, we were too close to you.
I remember you saying to me - don't bother doing all that again - I'll move!!
That was enough - the Delta had to go.
The difference in the anchors is significant - we just drop it where we want and it digs in.

Remember this pic - you found it a few months later - IIRC published on social media by the beach bar in that anchorage.

 

[Hurricane]

These pics aren't a great example but they do highlight the point.

This is my old Delta anchor starting to plough its way through the sand.


And this is our Rocna after about 3 days


You can see where the chain has been spinning round the anchor which hasn't moved.

Here they are, side by side - the Rocna IS bigger but the difference in performance is significant.

 

[jfm]

I definitely don't want to deepen an anchor debate but I spent nearly 20 years in the med on 25kg then 50kg deltas and never once had them drag, in some pretty howling winds and overnighters. Then I switched to an Ultra 55kg and that never dragged either. Now I have Pool-Ns and (admittedly in one season) they have never dragged either.

I'm sceptical abut these online/youtube tests - there is a lot of user input into anchoring and it's not all about the anchor, so one online guy's comparisons might not match the performance someone else gets. And how can anyone rate an anchor's "self launching power" from 1-5. That's total BS isn't it?

Hurricane in your post above of a sliding Delta and a holding Rocna, the substrates look different and the Rocna is bigger, so you're kinda proving nothing. I have never experienced what you first picture shows in decades of Delta anchoring.

 

[MapisM]

I definitely don't want to deepen an anchor debate ...

I have never experienced what you first picture shows in decades of Delta anchoring.

Neither do I, but I fully agree that there's much more than just the anchor type to consider.

Ref. experiences, FWIW I also can't think of any occasion where the very agricultural anchors of my previous boat dragged, but they were way oversized at 45Kg each.
OTOH, with the DP an its 25Kg Delta, I almost always see what Hurricane's pic above shows, right after setting the anchor and jump in the water to check it.
That's the nature of the beast I reckon - Deltas simply take a while to dig and set. But once they do, with an adequate chain scope, they aren't too bad.
Only in a couple of occasions, I think my anchor dragged further after setting.
I didn't even bother jumping in the water just to check, 'cause that happened during day anchorages, with someone always on watch.
Which is also the reason why I didn't release enough chain.

But if I'm honest, that isn't a solid enough reason to replace it.
As I said, I considered that more as a winter thought, while sort of missing an itch to scratch...
Currently, I'm thinking to leave the old Delta in its place for another another season (at least), and see what happens.

 

[MapisM]

the Rocna IS bigger but the difference in performance is significant.

M, what size was the OEM Delta, and how much larger did you go with the Rocna?
32 and 40Kg respectively, at a guess?

 

[MapisM]

Maybe your research was partly based on the anchor reviews by SV Panope, where the Viking scored quite high in both the 20 lb and 45 lb categories (see below)?


...I would worry about corrosion over time where the parts meet...

Research is a big word, but yes, as I guess most of us, I did check out some of Steve's videos. Winter nights are long!
And yes, even without his findings, it only takes common sense to guess that anchors like the Mantus and the Viking can be more prone to corrosion.
But in my experience, rinsing the anchor with a bit of fresh water is more than enough to make just about any anchor outlive its owner, and that's part of my routine by now. So, I wouldn't be too worried about it, should I eventually decide to give one of those things a try.
Also because let's face it, for those concerned about the anchor look (not me!), s/steel is the way to go...

 

[benjenbav]

View attachment 191205

Not doubting your experience at all, but looking at the two side by side I can’t see why (other than size) the performance should be chalk and cheese.

Obviously the Rocna is bigger and has the roll bar which will tend to help it turn point down, but once the point starts to bite the profiles look very similar.

 

[Hurricane]

M, what size was the OEM Delta, and how much larger did you go with the Rocna?
32 and 40Kg respectively, at a guess?

Not doubting your experience at all, but looking at the two side by side I can’t see why (other than size) the performance should be chalk and cheese.

Obviously the Rocna is bigger and has the roll bar which will tend to help it turn point down, but once the point starts to bite the profiles look very similar.

IIRC, the Rocna is 55Kgs
I can't remember the weight/size of the Delta.

But lots of people say that if you change from a Delta to a Rocna - size for size, you will get a significant upgrade.
I chose to go bigger on the Rocna.
For me though, the Rocna works every time - that Delta didn't.
Obviously, the Delta worked but I couldn't rely on it - and we are talking about having a good nights sleep.

Some on here may remember Deleted User.
He did the same as me - similar size boat - switched to the same size Rocna as me.
I think his previous anchor was a Delta but thats only from memory.
He experienced that same as me - a significant improvement.

 

[benjenbav]

IIRC, the Rocna is 55Kgs
I can't remember the weight/size of the Delta.

But lots of people say that if you change from a Delta to a Rocna - size for size, you will get a significant upgrade.
I chose to go bigger on the Rocna.
For me though, the Rocna works every time - that Delta didn't.
Obviously, the Delta worked but I couldn't rely on it - and we are talking about having a good nights sleep.

Some on here may remember Deleted User.
He did the same as me - similar size boat - switched to the same size Rocna as me.
I think his previous anchor was a Delta but thats only from memory.
He experienced that same as me - a significant improvement.

If the Delta is gathering dust somewhere it would be quite fun to dig it out and weld a curved bar on top and see if that made any improvement. Obvs just in controlled conditions as I would imagine you wouldn’t want to place any reliance on a bit of kit in which you’d already lost confidence.

 

[jfm]

Hurricane the Princess 67 came OEM with 40kg Delta. You can't change a 40 delta for a 55 Rocna and rationally declare that Rocna is a better anchor!

"Lots of people say" lots of things on the internet, but comparisons that are scientifically invalid must be called out.

Deleted User had a Bruce not a Delta, and switched to Rocna. His boat, Ferretti 630, came OEM supplied with a 30kg Bruce, which is a joke, so when he switched to a bigger Rocna it isn't much surprise that it worked better but that forms no basis to say that Rocna is meaningfully better than Delta AOTBE.

 

[Hurricane]

Hurricane the Princess 67 came OEM with 40kg Delta. You can't change a 40 delta for a 55 Rocna and rationally declare that Rocna is a better anchor!

"Lots of people say" lots of things on the internet, but comparisons that are scientifically invalid must be called out.

Deleted User had a Bruce not a Delta, and switched to Rocna. His boat, Ferretti 630, came OEM supplied with a 30kg Bruce, which is a joke, so when he switched to a bigger Rocna it isn't much surprise that it worked better but that forms no basis to say that Rocna is meaningfully better than Delta AOTBE.

Yep - but I have been quite open about my upgrade.
The anchor supplied by Princess didn't work very well.
The research that I did at the time indicated that the Rocna performed better than a Delta.
I have space for a 55 Rocna, so I chose a bigger Rocna.
Personally, I don't think that a bigger Delta would have worked either.

Lots of my yachtie friends have upgraded to Rocnas from Deltas - keeping the anchor the same size.
They all swear by them.

 

[Hurricane]

If the Delta is gathering dust somewhere it would be quite fun to dig it out and weld a curved bar on top and see if that made any improvement. Obvs just in controlled conditions as I would imagine you wouldn’t want to place any reliance on a bit of kit in which you’d already lost confidence.

I don't think it is the hoop that is the problem with the Delta.
I think it is the profile of the blades.
They seem to me to "part the sand" rather than "dig down".
Look at my pic above where the two anchors are side by side.
The Rocna forms a "kind of" bucket that stops it from moving.
The Delta seems to work rather like a farmers plough - pushing the sand sideways.

This is just my common sense/engineering observation.
I will, no doubt, get some alternate views on this.

 

[jfm]

Yep - but I have been quite open about my upgrade.
The anchor supplied by Princess didn't work very well.
The research that I did at the time indicated that the Rocna performed better than a Delta.
I have space for a 55 Rocna, so I chose a bigger Rocna.
Personally, I don't think that a bigger Delta would have worked either.

Lots of my yachtie friends have upgraded to Rocnas from Deltas - keeping the anchor the same size.
They all swear by them.

Yes to all that, but there's a lot less proper science going on there than just internet chat
I had a decade on 50kg Deltas on a bigger boats than yours and they never dragged. That's just an anecdote too, but I wanted my anecdote to sit alongside your "My mates and I think Deltas are rubbish" anecdotes, just for balance.

 

[roa312]

Yes to all that, but there's a lot less proper science going on there than just internet chat
I had a decade on 50kg Deltas on a bigger boats than yours and they never dragged. That's just an anecdote too, but I wanted my anecdote to sit alongside your "My mates and I think Deltas are rubbish" anecdotes, just for balance.

This brings us back to the reviews from SV Panope, which are the only good like-for-like tests conducted on equal terms . But as you said, there are bound to be user input differences, so the same anchor will likely perform differently across different operators/locations. I think you also mentioned in your build thread that, at the anchor weight of your Sanlorenzo, the anchor type doesn’t matter - and I imagine that’s probably true at lower weights as well, so the comparison of anchors is maybe only really relevant up to c.50kg?

When people report anchor dragging incidents online, it seems to me that if often stem from being stuck in overcrowded anchorages where they can't put out as much chain as they would like. SV Panope generally conducts his tests at a 5:1 scope (5x water depth), and perhaps you guys differ when it comes to the amount of chain set when anchoring conservatively?

@jfm: I also wanted to ask whether you think your stabilizers significantly reduce jerking on the anchor or if any effect from that is offset by the chain catenary?

 

[roa312]

Look at my pic above where the two anchors are side by side.
The Rocna forms a "kind of" bucket that stops it from moving.
The Delta seems to work rather like a farmers plough - pushing the sand sideways.

I agree with you on this. The Rocna blade is concave whereas the Delta is convex. Add to that the roll bar and these two anchors become quite different in shape. That's not to say that one is necessarily better than the other though.

 

[Hurricane]

Here is a better photo of the two side by side