Does a New Generation anchor need to be oversized?

[vyv_cox]

How do you know this... When did rocnas become "not bendy ones"?

According to Steve Bambury, then the director of Rocna, the 'bendy' shanks were produced "in the first quarter of 2010." I destructively tested a Rocna bought in May 2011, after the CMP buyout, and found it to be satisfactory although not quite as strong as called for in the original specification.

I am not totally convinced that production of the defective shanks only lasted three months but anything from 2011 onwards would seem to be OK.

 

[Neeves]

Hi Jonathan
I enjoy reading you posting, you can write some very good articles but there are times that you just don't convince me because my hands on experience isn't what you find in your tests or your option I sorry to say.


No one going to convince me a one size bigger anchor can be set, for one simple reason , we been doing it for the last 10 years on two different boat with two different engines .


Any way going forward a step,


I really think it's time Noelex and you burned the hatched or the anchor, your two great guys with good info and it's just putting a downer on anchoring thread we can almost predict one or the other going to trash is other posting .


You both have different view on the Mantus, just has we all have a different view on anchors , sizes and chain .

Thanks Vic,

As long as people are going to spruik anchors and not understand their basic fundamentals I will continue to post as I have done. As long as people suggest, repetitively, daft ideas like 'a larger anchor is safer at short scope' and is unable to justify the comment with a single time it was used - I will continue to post as I have done.

Your choice of chain is not likely to cause anyone to have an accident. Going one size bigger on anchor is neither here nor there (and does not prove it is necessary) - spruioking an anchor and suggesting it is better than a Rocna when it has the hold of a Delta is ignorance and inexcusable - too many people bought a Mantus based on Noelex thread - its wrong.

Who is going to say what I say if I back off? Who is going to do the tests - where will they be reported. How many here read the article on anchor angles - Viking read it, changed their design, improved their hold - but what of the people who did not read it - they would continue to buy Mantus thinks it was better than a Rocna. Sorry - not my style.

Finally - Brning books never works - the truth eventually comes out. I'm sorry it took me so long to work out the issue with Mantus.


Sorry Vic, thanks for the advice.

Jonathan

 

[sailaboutvic]

Thanks Vic,

As long as people are going to spruik anchors and not understand their basic fundamentals I will continue to post as I have done. As long as people suggest, repetitively, daft ideas like 'a larger anchor is safer at short scope' and is unable to justify the comment with a single time it was used - I will continue to post as I have done.

Your choice of chain is not likely to cause anyone to have an accident. Going one size bigger on anchor is neither here nor there (and does not prove it is necessary) - spruioking an anchor and suggesting it is better than a Rocna when it has the hold of a Delta is ignorance and inexcusable - too many people bought a Mantus based on Noelex thread - its wrong.

Who is going to say what I say if I back off? Who is going to do the tests - where will they be reported. How many here read the article on anchor angles - Viking read it, changed their design, improved their hold - but what of the people who did not read it - they would continue to buy Mantus thinks it was better than a Rocna. Sorry - not my style.

Finally - Brning books never works - the truth eventually comes out. I'm sorry it took me so long to work out the issue with Mantus.


Sorry Vic, thanks for the advice.

Jonathan

Thanks telling me

 

[Neeves]

According to Steve Bambury, then the director of Rocna, the 'bendy' shanks were produced "in the first quarter of 2010." I destructively tested a Rocna bought in May 2011, after the CMP buyout, and found it to be satisfactory although not quite as strong as called for in the original specification.

I am not totally convinced that production of the defective shanks only lasted three months but anything from 2011 onwards would seem to be OK.

I still have all the files for the bendy shanks saga, which includes every Rocna shipped with a bendy shank, but I simply don't remember the dates. If anyone wanted to know - send me a PM.

To me its history, its over - unless you happen to acquire a Rocna and know when it was made and want to know if it is one of the suspect models - but it lasted much longer than 3 months. Steve Banbury owned Holdfast who had the marketing licence. It was never precisely clear who had responsibility for what on the production side, though Banbury was a key feature.

Since CMP took over there have been no complaints.

Jonathan

 

[coopec]

I think you will find the Rocna is priced as such - because that is what people will pay.

I don't think you will tell the difference in terms of performance. Neither will work in soft soupy mud (buy a Fortress), both will carry seabed (have a good deck wash - and consider Morgans Cloud's comments) both will have a real issue in weed (clogging). Both are excellent in firm mud (have a good deck wash) and in sand. The Supreme has a lovely tripping slot (that you will probably never use - as you cannot know
when you will need it)

Jonathan

"and consider Morgans Cloud's comments) Please elucidate (look it up!)

Ok Jonathan, is the Manson Supreme any use on a coral bottom as I would expect at the Abrolhos Islands off the coast of Western Australia? Maybe I have to carry an Admiralty Pattern anchor as well!!!

 

[pandos]

Th

According to Steve Bambury, then the director of Rocna, the 'bendy' shanks were produced "in the first quarter of 2010." I destructively tested a Rocna bought in May 2011, after the CMP buyout, and found it to be satisfactory although not quite as strong as called for in the original specification.

I am not totally convinced that production of the defective shanks only lasted three months but anything from 2011 onwards would seem to be OK.

That sounds good....pretty sure Amazon don't keep anything hanging around that long...all will be revealed in time...

 

[vyv_cox]

Th
That sounds good....pretty sure Amazon don't keep anything hanging around that long...all will be revealed in time...

If a Rocna has its name pressed into the back edge of the fluke it is CMP production.

 

[Neeves]

"and consider Morgans Cloud's comments) Please elucidate (look it up!)

Ok Jonathan, is the Manson Supreme any use on a coral bottom as I would expect at the Abrolhos Islands off the coast of Western Australia? Maybe I have to carry an Admiralty Pattern anchor as well!!!

Morgans Cloud is the name of the yacht owned by the people who run the website Attainable Adventure Cruising, AAC. Its a subscriber site, I don't subscribe - but I do get sent copies of article relevant to my interests. Some on YBW subscribe and think highly of the AAC advice. I also think it good, but you can find the same advice in other places - if you search. AAC puts it all in one place.

Check this:

Resetting Failures With Rocna and Manson, and Some Thoughts on Vulcan and Mantus

This may be a shorten version of the script they wrote when they originally withdrew their recommendation for Rocna, but its all there. They have written, subscriber only, a review on Excel. Send me a PM and I might, I stress the might, be able to get access for you.

One of the problems of roll bar and concave anchors is that they can collect large items in the fluke (like a big stone or lump of coral). I have a friend a reservists in Oz Navy and to keep his ticket up he drives, Lt Commander, landing craft up and down the coast, a bit like moving hire cars around and back to their depot. He was up near Cape York and then got a big lump of coral caught in the, supplied, Bruce anchor - they needed a crow bar to get it out (just the sort of thing we all carry!) So concave anchors don't only clog with mud, weed and weedy mud. A convex anchor would be less prone. We anchor in Jamieson Bay when crossing Bass Strait (its bleak and bit like the end of the world) it, unusually for Australia has a stony bottom, boulders - about head sized - we would not use our Spade, nor Fortress - but the Excel copes.

Now you should not be anchoring in living coral but in coral rubble and the sand patches. When in the Whitsundays we used both a Spade, we also have a steel one, or the Excel. In daylight you can see living coral and the sand patches - don't move in coral at night!

I'm sorry but I don't know of a perfect anchor. Our Fortress cannot be beaten in slimy, soupy mud (the sort you find round oyster farms and many of Oz rivers). Its also great in sand - but really a liability in weed and anywhere with stones of a size to get caught between the flukes (like Bramble Cove, named after HMS Bramble, in Port Davey). The Excel and Spade are pretty useless in that soupy mud but the Excel is good in thin to medium weed and sand and the Spade is good in sand and heavy mud (we have a good deck wash). We carry the Excel as our primary and the Spade could replace it, should we lose the Excel. Our anchors are all aluminium so are light and all can be demounted, so the pieces are easy to pack away.. We carry a FX16 and aFX 37 because we found the FX23 could not be set deeply and the stock stood proud and was there liable to tripping, so the FX 16 can be buried. The FX 16 is not big enough for reliable hold in soupy mud - so we carry the FX 37. If we set up a 'V' we would use the Spade or FX 16 alongside the Excel. The Fortress are not easy to assemble in the dark on a cold wet night but our fore deck locker swallows them both, assembled. The Spade is easy to assemble, slot in the shank, one bolt. We store all our anchors with a shackle that fits the chain. We had the Spade before the aluminium Excel was introduced and though, on balance the Excel is slightly better - in the dark you cannot tell the difference

We cannot anchor in thick weed or kelp - we would need a big fisherman - and we are not prepared to carry one. Kelp and thick weed is commonly well charted (in the older versions of the Admiralty Pilots (for Australia) so we simply avoid them. Kelp grows on rock(s) it is to be avoided anyway.

Personally I would not buy a Vulcan - until there is more information - but people are buying it - there are other anchors that are 'tested' that are similar - though for Oz both are expensive, Spade or Ultra. I'd recommend a Kobra - but I have no idea how you could get one, sold by Plastimo. You need at least 2 anchors, whatever you choose as a primary - and something to replace it (and I'd buy a different style) as people do lose anchors. I think you would need a Fortress, kedge, mud (stores assembled flat).

Jonathan

 

[Neeves]

If a Rocna has its name pressed into the back edge of the fluke it is CMP production.

Sorry - I don't know what happened originally when they transferred production from NZ to Shanghai (except they screwed a lot of people). One of the reasons was to stop fabricating the flukes, cutting steel and welding it together, but casting. Some of the bendy shank anchors have a cast fluke with Rocna, the kiwi logo and the weight cast into the rear of the upturn on the heel - I know I have 2 models, a 10kg ungalvanised version and a fishermans, sort of like a Supreme with the tripping slot. The 10kg model has a cast fluke and bendy shank, from memory 420 MPa, I followed Vyv's test with the ball bearing (and subsequently bent it to find out how easy it was to bend!).

The story I gleaned was that the anchor was fabricated, all welded, from different steels. When it was galvanised, in China, the finished product 'looked' odd as the different steels accepted the galvanising differently. I don't know enough about galvanising to know if this sort of thing can be overcome (though spraying the items with silver paint is one answer). The answer they came up with was to dispense with the 800MPa steel and use 420 MPa mild(er) steel - and the rest is history. The galvanising bath was coal fired - I don't know if that was significant - I just thought it 'quaint'.

But some bendy shank anchors had a cast fluke.

One reason Rocna lost its Rina certification - they never told Rina they had moved to a cast fluke and the Classification Societies are very stringent on cast components and insist to assessing the casting process.

The larger anchors, 55kg and larger were always fabricated (and still might be). Anchors that size are outside my 'market' area.

Jonathan

 

[[176172]]

But then how many people have been heard to say "I wish I had an oversized not properly set more expensive anchor, than a cheaper appropriately sized well set anchor" ??

The first question was rhetorical, this one unrealistically based on cost.

 

[[176172]]

I though the OP and Crina had it dead on. New anchors are better. I had a Delta.

Some cruisers like to go massive. That's OK for them. Much depends on how often and where you anchor. If you expect to sit out a tropical storm on questionable holding ground, monster is good. If you anchor in very soft mud (Chesapeake Bay) and have strong thunderstorms, big is good, although standard Rocna sizing is conservative.

It's not about the money. Really. It's not about the weight, unless you carry a lot of over wieght chain.

Then there is the internet fear factor.

I've done a lot of testing for articles and a book. Perhaps the clearest lesson is that few anchors drag because they were overwhemed in good holding ground. There was always another factor, and that other factor reduced holding by 3-10 times. A 20-30% larger anchor won't solve that.

• Trash. The anchor fouled on a stick or shell. Or perhaps the chain fouled, preventing digging.
• Soft spot.
• Weeds. The anchor caught on weeds, but broke loose when it really blew.
• Underlying hardpan. Very hard to detect, even with power setting.
• Yawing or hobby horsing.
• Stupidly short scope. Rare.

Often the error band on anchor testing is +/- 60%. In that case, you move to more consistant bottom for testing. But the cruiser does not know this. I have 4 favorite testing areas, where I know the bottom is consistent. I also have places with know problems (rock, hardpan etc.).

Unless the anchor is tragically undersized, it is not the reason you are dragging. My 2-pound Guardian will reliably hold 500 pounds (the wind load of a 38-foot boat in 30-35 knots) in good sand. A conventionally sized Rocna or Manson will hold well into huricane force.

But you can argue it to death, which I'm sure we will. How safe is safe? What are your anchoring bottoms like? How much care do you expend? How owten do you anchor? Do you anchor out in severe storms (winds over 50 knots, not just a lot of rain)? But rememmber, if you anchored on hardpan, an extra 15 pounds isn't going to make an important difference.

I take from that, and very grateful to you for highlighting it, what many of us know about and are faced with the unknowns below us when anchoring in a new area.
I also take from the above that having a larger, within reason, than recommended anchor, of a modern construction does with all things being equal, if not eliminate, then does protect against the dreaded drag.
If I may add, good watch keeping where possible whilst anchored, or an audio warning does of course go a long way to prevent the sort of tragedies we read about and could possibly be our fate, when it is to late to take remedial action.

 

[thinwater]

Kp is kilopond, unit of force. Source: Schult, Richtig Ankern, Delius & Klasing, page 56 (in German) based on a French test, according to source. Units for holding power are in Newton. I apologize for not being specific enough. So, holding power equals 700N per kg, tops.
Even using the numbers from the test in Voile magazine we are still plenty safe.

In English and American engnineering, kilopounds is abriviated Kips. He was German and didn't know. define Kips

You inadvertently made a mistake in the conversion between kg-force and newtons, missing the gravitational constant (9.8M/S^2).

Thus, the 400-700 range is actually 41-72 times anchor weight. This is in line with what I said above and other testing.

 

[Crinan12]

The first question was rhetorical, this one unrealistically based on cost.

Not sure what that means really

 

[Refueler]

But then how many people have been heard to say "I wish I had an oversized not properly set more expensive anchor, than a cheaper appropriately sized well set anchor" ??

Surely the cry will be ; WTF am I doing here !!!!

 

[lw395]

In English and American engnineering, kilopounds is abriviated Kips. He was German and didn't know. define Kips
...

Not in British English Engineering. What the Rig Pigs call a 'Redneck Unit'.
Even your 'requires verification' wiki reference doesn't accuse British engineers of using it.

 

[thinwater]

Not in British English Engineering. What the Rig Pigs call a 'Redneck Unit'.
Even your 'requires verification' wiki reference doesn't accuse British engineers of using it.

You have no idea how little that bothers me.

I don't use rods, stones, imperial gallons, or fathoms either, but I know what they are.

 

[Laminar Flow]

You have no idea how little that bothers me.

I don't use rods, stones, imperial gallons, or fathoms either, but I know what they are.

Air Canada pilots confusing imperial gallons with litres does bother me. Especially if I were to be on board and they (again) would have to emergency-land and a passenger jet on a prairie air field that hadn't seen much traffic sine 1918.

 

[pandos]

well my Rocna arrived via UPS today. (bargain on Amazon)

Looks brand new, and would seem to have been quality checked in 2019 it has plates glued to either side of the shank with.... 20 Rocna and CMP etc.. on the shank just where it is welded to the body there is stamped 821,, on the underside of the heel there is Genuine Rocna 20k//44lb stamped.. on one side and Rocna and their trademark symbol on the other side...

is this likely to be a "bad/ bendy Rocna"...

 

[vyv_cox]

Highly unlikely that any of the soft shanks exist 10 years after the event. The markings you describe post-date all of that, i.e. CMP bought the company after the crisis.

 

[doug748]

I've only read a couple of pages of the thread so far so I suppose I should not be commenting but when I read thread comments like the following I have to take notice.

I'm now leaning toward the Manson Supreme mostly because the Rocna seems to be overpriced
Rocna 55lb $1125
Manson Supreme 60lb $799

Rocna vs Manson Supreme Anchors

View attachment 84760

I have a Rocna but would say the Manson looks to be the stronger construction, the shank is very robust. I think the chap from S V Panope said a similar thing on his compilation video.

I am sure the Manson would suit you fine.