Rocna Resetting Failures and evaluation of Vulcan and Mantus

This was a tough article to write back in 2016 when we first published it, and it's a tough one to update, too:

  • It was no fun to reverse ourselves from our long-term recommendation of the Rocna anchor.
  • The article resulted in more angry personal attacks on me than any other we have ever published, at least since we restricted comments to members.

However, we are dealing with a particularly dangerous dragging modality that could result in lost boats, or even lost lives, so publishing, and republishing, this is worth the aggro. Particularly since being aware of the weakness can go a long way to managing it.

Just wanted you to know I don't enjoy calling gear that is much loved by many into question.

With that out of the way, on to the meat of it.

Many of you will be aware of the excellent work Steve of S/V Panope has done by rigging up a waterproof video camera in such a way that it allows the viewer to see exactly how an anchor sets, or not, in the real world.

As part of that testing, Steve subjected each anchor to a true resetting torture test by motoring across the position of the set anchor and coming up on the rode at 180 degrees to the original line of set, in order to simulate what happens in a radical wind-shift.

This part of Steve's testing confirmed that many modern anchors reset amazingly well, even after a radical and sudden pull-angle change.

A Scary Problem

That is, with the exception of the repeated reset failures with the Rocna, which you can see in the video above. To really understand what's going on here, you need to watch the entire 11-minute video.

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.

  1. Introduction
  2. 4 Vital Anchor Selection Criteria and a Review of SPADE
  3. SARCA Excel Anchor—A Real World Test
  4. SPADE, SARCA Excel, or Some Other Anchor?
  5. Rocna Resetting Failures and evaluation of Vulcan and Mantus
  6. Some Thoughts On The Ultra Anchor, Roll Bars and Swivels
  7. Specifying Primary Anchor Size
  8. Kedge (Secondary Anchor)—Recommended Type and Size
  9. Third Anchors, Storm Anchors and Spare Anchors
  10. Anchor Tests—The Good, The Bad, and The Downright Silly
  11. Making Anchor Tests More Meaningful
  12. We Love The Way Our Anchor Drags 
  13. Things to Know About Anchor Chain
  14. Selecting a Chain Grade
  15. Anchor Chain Catenary, When it Matters and When it Doesn’t
  16. Anchoring—Snubbers
  17. Anchor Rode Questions and Answers
  18. Q&A: Hybrid Rope And Chain Anchor Rodes
  19. Anchor Swivels, Just Say No
  20. A Windlass That Makes The Grade
  21. The Perfect Anchor Roller
  22. Install A Wash-down Pump—And Save Money!
  23. Anchoring—Kellets
  24. Anchoring—Chain: Stoppers, Termination and Marking
  25. 20 Tips To Get Anchored and Stay Anchored
  26. Choosing an Anchorage
  27. Choosing a Spot
  28. 15 Steps To Getting Securely Anchored
  29. One Anchor or Two?
  30. Two Anchors Done Right
  31. It’s Often Better to Anchor Than Pick Up a Mooring
  32. Yawing at Anchor, The Theory and The Solution
  33. Yawing at The Anchor, an Alternative Cure
  34. How To Use An Anchor Trip Line
  35. ShoreFasts—Part 1, When to Use Them
  36. ShoreFasts—Part 2, Example Setups Plus Tips and Tricks
  37. ShoreFasts—Part 3, The Gear
  38. Gale And Storm Preparation, At Anchor Or On A Mooring
  39. Storm Preparation, All Chain On Deck
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James Hallett

I have only recently started to use a Vulcan on a small power boat in Bermuda. I expected great things from this anchor in terms of setting ability, but in my limited experience so far, it often takes several attempts to get a good initial set, so I would sincerely doubt that it would do well in a reset test.

James

Lee Cumberland

As I type this, we’re on anchor with our 33kg Rocna in a 180 reversing tidal creek with sticky mud. I’ve heard reports from other cruisers about sticky grass/mud in Mexico fouling the fluke/tip after several shifts. That said, most people we see are still convinced an undersized Danforth or CQR is more than adequate…

Jeffrey Holt

Based on AC’s recommendation, I started using the Rocna two years ago. All of my sailing experiences so far has been on the coastal waters of Maine. Tidal shifts are pretty normal, especially in a number of river influenced anchorages. I have never had an issue with the Rocna failing to set or reset. That’s a good thing, but to be honest, it has also led me to become overly comfortable and trusting of the set. The two key questions I have from watching the testing relate to scope and anchor weight. The tester makes mention that the 33 lb anchor is probably a tad light for the boat under test. How does this factor mesh with your recommendation to oversize the anchor? I chose the 44 lb Rocna for a 34-foot full keel boat. Second, the anchor was set with a scope of 3.5 to 1, which seems a poor choice given the expected “extreme weather” conditions of the test. I always set with as much scope as possible and then pull back up onto the anchor if I have to reduce the swing radius. I still retain full confidence in the Rocna, but based on your comments, I will be returning to more deliberate measures for monitoring performance.

Tim

Since bending our old Bugel type a month ago we bought a Spade on Colin’s recommendation even though he currently uses a Rocna. Anyhow a friend simultaneously took delivery of a Vulcan. Two observations are that mine new 30kg spade looks small compared to his Vulcan even though his is rated for a smaller boat. Secondly the Vulcan does, by all accounts, look higher quality. The welds, colour of material etc.

Point 2 is neither here nor there, let’s face it, so I’ll leave that alone but a lot of people might not like spending that sort of money on a spade when it looks reasonably rough and ready.

Point 1 comes down to manufacturers sizing recommendations. I mean where do we stand on this? Who gets to say what size or weight is correct and is Rocna just way over sizing their recommendations to make its competitors look small or are spades sizings a little on the tiny side?

We’re a 17t displacement so went for the 30kg. Correct size as per their recommendations but it does look small compared to similar Rocnas and especially the Vulcan “equivalent”.

As for performance I can only say that the Spade has been bomb proof up in the Outer Hebrides in what has been regarded the most windy August on record. Happy so far!

Colin Speedie

Hi Tim

the difference in apparent size is probably easily explained. The Spade is ballasted with lead to make the anchor adopt the correct plane to penetrate the substrate and dig in fast. The Rocna and other roll bar anchors use the roll bar to do the same job, with no ballast. This allows them to move the weight of the ballast into other areas of the anchor, notably the fluke area – so they are bigger.
As far as sizing is concerned, I don’t think there’s much difference in the advice given – A Rocna or Spade of the same weight would do the job. What is different is the anchor sizes – and in my estimation the Rocna 33 (73lbs.) and the Spade S160 (77lbs) are the two to compare, as close to like for like as possible.
Where we all struggle is the old formula trotted out as a general rule of thumb of 1lb of anchor for 1ft LOA. So a 45lb anchor for a 45ft boat. This is/was based around a windspeed of (from memory) 35 knots, which, as we know is nothing in the real world of cruising in remote areas.
So scale up accordingly and sleep soundly!
Best wishes
Colin

Kjeld Pedersen

Dear John
Interesting and scary article about Rocna anchors. I’m using a 33 kg Rocna anchor for our 45′ catamaran and was considering buying a Spade anchor as an extra for our comming circumnavigation, as it is dismantable and therefore easy to store in a locker. But now we might have to change our mind and change to the Spade as our main anchor! I mis a 100% similar test of the Spade anchor, who know if the Spade acts in the same way as the Rocna. Will there come such a test and done at the same location to ensure the test is comparable?
Thank you for many informative articles which we are studying carefully during our preparation for our big adventure next year
Best regards
Kjeld

Dartanyon

On our previous boat, a Baba 30. We had anchored many seasons on a 35lb CQR that was original to the boat. After hearing all the talk of the new anchors we purchased a 33lb Vulcan (roll bar anchors will not fit on our bow). We only used it last summer before selling the boat this May, but my experience was very similar to the video. It would set beautifully in nearly all conditions; however some of our anchoring was in the Hood Canal, in an area with about a 2.5 knot tidal current. When we were anchored there; 33% of the time the anchor would drag on the tide change. We got in the habit of always being on the boat during the flop and if we felt like we hadn’t gotten a good reset we’d power set the anchor often dragging for a bit. I began to think that it’s actually a balance problem, once anything (mostly sand up here) weights the back side of the fluke down where all the area is, the tip is no longer heavy enough to bite. Unfortunately, our new boat, a N447, has a brand new 73 lb Rocna on the bow … I guess I’ll need to start budgeting for a Spade.

Marc Dacey

While I think this sort of test is informative to a point, I always marvel at the idea that 3.5:1 is anything better than a “lunch-hook” ratio. It’s not something I would seriously attempt. Even in calm-10 knot air with a known ground, I lay out 5:1 (often on a oversized Fortress for “lunch” purposes or if we wish to swim from the boat).

What *is* helpful is seeing the setting behaviour. I saw Steve’s 4:1 SPADE test (#27: https://www.youtube.com/watch?v=KvVITS3nHHQ) and that shows very convincingly the weighted tip advantage. Even if I would never close my eyes at less than 6:1 even if the forecast was benign. One of the most distressing aspects of “new model anchor” marketing is the promise of “you have the holding power of 7:1 at a scope of 5:1!” Well, that implies the same old scope of 7:1 gives you close to the hold of 10:1…why wouldn’t you just keep the old conservative habit, which allows shock loading and a proper catenary?

Thanks, John, for wading (again) into this. We’re getting a SPADE. It’s less that 1% the cost to replace our boat, not counting every improvement and thousands of hours of labour. Why does price even enter into that equation?

Marc Dacey

Re: snubber/bridle: Sorry, I thought that was implied, John. Only in the “benign lunch hook” scenario (which implies a rope rode with a chain leader, little wind or tide and a known, decent ground) do I anchor without a waterline snubber or a bridle.

As for catenary, I think it’s been shown that you can get away with less scope in deeper waters without penalty, but the anchor tests shown were done in shallow (9-15 feet) of water, which is where I would not consider 3.5: 1 or 4:1 to be realistic for overnight.

As for price, the SPADE “S” Steel S140 (30 kilos/66 pounds) is $1,175.00 (U.S.) on the U.S. distributor’s site, whereas the most comparable Rocna (73 lbs.) is $859.00 (U.S.) at West Marine. So, less than one third of a boat buck. Everything’s relative.

Dick Stevenson

Hi John,
Is there a citation to Eric Klem’s observation that there is more shock absorption in chain stretch than in catenary?
Thanks, Dick

Eric Klem

Hi Dick,

Sorry for jumping in here so late, we just got back from a few weeks off the grid on the boat.

Let me start by clarifying the statement slightly. Going from a “reasonably high load” all the way up to the yield strength of the chain, the difference in the distance of the endpoints of the chain will vary more due to the chain deforming (elastically meaning it is not permanent) than due to the catenary. For reasonable load, I am talking something on the order of 1/10th the tensile strength depending on the specific situation. If you start at a really low load, then catenary obviously is a major factor until you get into higher loads.

The way I came to this conclusion was by calculating it out one night when someone pointed out to me that I always ignored link deformation. I don’t have the calculation in front of me but I believe I was using 200′ of 3/8″ HT chain with an ideal catenary curve (2 attachment points horizontal to each other with no ground in between) and a starting load of 1000 lbs. I then recalculated at a few other loads like 2000,3000, 5000 lbs and found that the difference from 1000 lbs was greater for link deformation than catenary. For anyone interested in learning more about catenary, I highly recommend googling something like “catenary calculator” and plugging in numbers. The most interesting thing to look at is the distance between the cable/chain length and the distance between the attachment points, they are almost the same for any reasonably high load meaning that taking out additional catenary will dissipate very little energy.

I hope this helps.

Eric

Dick Stevenson

Hi Eric,
Yes, it does help. Every little bit helps me to wrap my head around the various elements that contribute to keeping Alchemy struck to the bottom and which are likely to make the most difference when things heat up a bit.
Thanks, Dick

Drew Frye

I differ on one several facts, and this is almost certainly because I think anchoring in 5 feet of water is a normal thing (catamaran, mud bottom, little tide range) and I use outboards for power (weak in reverse). I’m pretty sure you would have a foot of boot top showing in some of my favorite places. Though I’ve not voyaged, I’ve done enough instrumented testing to pretty sure of a few things. Engineering.

In that sort of thin water, a 3:1 scope is only 24′ of chain (including an allowance for freeboard). First, with a bridle or any decent snubber, that is practically no chain. Setting is nearly impossible, because even on all chain (remember that you have almost no chain in the system–catamarans rig the bridle before setting, or we would be backing down against the windlass), it doesn’t take but 20 pounds or so to lift the chain off the bottom. So the “no engineering basis” comment requires a caveat stating “for depths over 15 feet.” Otherwise you need more rode to set.

Second, although after setting I agree that scope has less impact than commonly thought (the chain is at a different angle underground), that is not true during the initial set, and with over-size anchors, most sail boats cannot set the anchors deeply with reverse. I know I can’t. With any large anchor in good sand, the shank will still be on the surface and the scope is what the anchor will feel. We rely on the storm to provide the real setting force, and that means we will need longer scope for a while, during this extended setting. I think that math is defensible.

Finally, I’ve never seen my cat sail at anchor at all (long bridle). I also have more limited mass. Thus surging is a non-issue for me. However, watching some boats zig through what must be their tacking angle, I agree that is a MAJOR issue. And it would drive me crazy being on board.

In deeper water, and after the anchor is set, we are on the same page. I broke a load cell testing with no snubber (just for background info) when a 2-foot wake came through in only 10 knots. Bam. I was sitting right next to it and was jolted. Felt like we hit something.

Marc Dacey

Drew, interesting and (to me, even with a heavy displacement monohull) relevant observations, especially on the suggestion that there’s a lower limit of chain rode out that could be considered “enough”. Your difficulties with power sets in reverse would indeed make for different techniques by which you could compensate for that tricky period before your anchor “self-buries”. As for surging, veering and hunting at anchor, there are means to lessen this, such as riding sails, that just aren’t as common as one might think.

Drew Frye

I’ve always wondered how much a dinghy lashed to the foredeck impacts sailing at anchor. I have a large hardtop and davits (plenty of windage aft) and a bridle. On the other hand, it seems to me that some of the most nervous boats are those with a dinghy up front. Sort of a reverse riding sail.

The corollary is what advise should be given for storms. Deflate the dingy? Take it ashore? I’ve heard of dinghies flipping in high winds when left floating; I always wonder how long the painter was and if the boat was sailing a lot. Otherwise, how did the dinghy get out into the wind stream? Would it have been OK on a very short, properly centered tether? I suppose this depends on how much the boat surges, causing it to get sideways once in a while.

Still, the foredeck seems wrong, even for a strong squall.

Eric Klem

Hi Marc,

I would encourage you not to get too hung up on one specific scope number. If you are unable to sleep at anything less than 6:1, you will miss an awful lot of good anchorages and take up more room than is courteous in many more. I just got back from anchoring in a place where tides are greater than 20′ and most of the anchorages are around 20′ MWL so we would have >45′ between the bottom and bow roller often and we often could only put out 150′ or we would hit something. In our most common cruising grounds, I would estimate that I would have to bypass a full third of the harbors we go into if I had a 6:1 rule and I don’t think of myself as particularly adventurous. In the Pacific Northwest, I would guess that the number would be above half, some people there anchor at insanely short scope although it can also be ridiculously deep, there are many anchorages there that I refuse to go in.

I always refer to my scope as what I find at high tide. If there is going to be greater than 30′ of water, I shoot for 3.5:1 or greater with a normal forecast because I have tried to torture test our anchor at shorter scopes than that and been unable to generate a failure until much shorter scope. As the water gets shallower, I slowly increase the scope until I hit the point where I never let out less than 50′ and rarely less than 70′. By using at least 50′ at all times, I don’t have to worry about the anchor struggling to set because of the chain pulling up too much on it. If you are sailing in clear waters, I like to make sure that there are always at least a few links of chain sitting on the bottom even in the big gusts.

Like John, I shoot for 5:1 in poor weather as long as the water is relatively deep. We carry 225′ of chain because it equates to 5:1 in 40′ of water for us. I have not experimented on our current boat but on other boats, I have found that excessive scope leads to excess yawing.

Eric

Marc Dacey

Thanks for your comments, Eric. I do take tidal factors into account and hope to anchor in both Nova Scotia and Brittany (again, but in our own boat) in the reasonably close future. All my comments regarding scope can be taken to be idealized rather than a hard and fast (pun unintended) viewpoint. Of course, crowding, state of the ground and weather forecasts, currents, tidal range/time of the month, etc. all play a role. Let’s face it, a lot of people who grasp little or none of these things never drag, just as people who carry drogues never see more than 40 knots. Preparedness goes in two directions in that respect.

Christopher

Spade 160 anchor on a 47′ aluminium boat, 3 years live aboard experience to a few remote places. We dragged exactly twice:

1) Anegada in the BVI, user error (idiocy comes to mind actually) combining anchoring in 1.2 meter depth, tight anchorage, short scope (3:1), and forgetting the height off the water of the bow (1.5m)… 36 hours later + 20 cm of tide and she was off to visit the other boats in the anchorage. Can’t blame that on the manufacturer or design.

2) We were in Elephant Cove on South Georgia, anchored in a 5-6m depth with 40+ m rode in significant williwaws for 8+ hours with 40 knots from one side and then 45 knots from the other a minute later. Tacked briskly back and forth on the rode all day and finally we noticed (needed radar over several minutes to confirm) we were very slowly easing back – figured we had literally plowed and furrowed the ground around the anchor. Ground was pink mud (Krill in the local Fur and Elephant seal diet) and pretty slick stuff. Always wondered if we might have been better off on less scope that day. A small sea anchor on the rode would have helped a lot. Never doubted, nor dragged once set, the Spade at other times when it really blew hard.

Dick Stevenson

Also, I would expect, the continued hard pulls side to side have to allow at least a few inches of movement before reset: like wiggling a spade shovel in the earth to get it a bit lower when digging. These have to add up over time, but likely not in any problematic way.
Dick Stevenson, s/v Alchemy

Bill Koppe

Hi John,
Once again thank you for your very useful site.
My experience with anchors is limited to CQR.
I had a 45lb on the 45ft 20t yacht and dragged on several occasions .
After anchoring badly in 50 knts and a big swell I ripped the chain through the timber bowsprit after demolishing the roller set up/
In the repair I changed to a 60lb CQR and upped the chain from 10mm to 13mm and never dragged again.
Now on the 80 ft Lloyds require a 100 kg CQR and I have upped that to 130kg .
I also calculated the angle of a 5: 1 scope from the bow roller to the ancor set in 10m.
By leading the snubber through a block attached at the waterline I found that a scope of 3:1 gave me the same angle. I believe this angle is the critical factor rather than the scope.
Lloyds required a 16mm chain and this has a break of 12t.
I consider that inadequate on a 58t yacht taking into account snatch loads, as in a large swell, and went to a 16mm stud link chain which did not increase the weight a great deal but increased the break to 19t.
As my spare anchor, I will follow your advice and get a 165lb (72 kg ) Spade and an alloy Spade for my stern anchor. These will also be much easier to sow and deploy. The large CQR was not a lot of fun to manouver in and out of the sail locker even with 2 cranes and 2 people. Would have been fun with a jockey pole and electric winch by myself.
I also worried about a large size and weight on the bow in a seaway and built a box that turns over the same axle as the roller which then moves the weight forward allowing the anchor to self launch while holding the anchor tightly in the stowed position both vertically and from side to side. This box also encloses the chain so it cannot jump the roller cheeks.
Finally a word of warning re hi tensile and load rated shackles.
These are not to be used underwater as they will suffer from hydrogen embrittlement leading to sudden failure.
Kind Regards,
Bill Koppe.

Clarence

It’s 0338 hrs in Newport harbor RI. A couple hours ago a squall came through with 180 degree wind shift. Estimate 0 kts to around 25-30 kts. Our 55lb Rocna pulled and we drug into a cat anchored too close. I estimate a 100 meter drag before we reset. Had 100′ of chain out. We’re a 18000 lb sailboat. Muck bottom. Several other boats drug. We’ll pull at first light and see what’s up. Time for a quick nap.

Tim

Hi John,

We have corresponded before on anchors, and you did indeed recommend me to use a Spade over a Rocna. I am due to make a final decision on this shortly (as the boat is currently under construction). This has now got me over the line for a spade ! Now I need to go and figure out sizing. I noticed on the spade web site that their anchors are offered in three different types of material…can you give me a steer. My yacht will be 47 feet and built from aluminium.

Many thanks

Tim

Geir ove

this is a film from carib, showing the Spade not doing what it is made for ? https://www.youtube.com/watch?v=-v6ws82gMF8&feature=youtu.be

i think the setting of the anchor is more important, and Rockne and spade are good anchors.

doug siddens

My comment is about the methodology of this powered reversal test.
I assume that the two lines which appear attached to the roll bar are for the camera. When the reversal takes place I see the two lines billowing. Because of the apparent attachment to the roll bar there is a leverage on the anchor which is reducing the tips downward force. How much?
When the speed is slowed the force on the camera lines is reduced and the tip has more downward force.
But, this does not account for failures to reset where there are no lines attached to, presumably, the roll bar.

Marek Nowicki

We upgraded (?) from 45 lbs Delta to 45 lbs Vulcan last year and so far no problems. Our boat is 35 ft Cape Vicker made in South Africa to B. Roberts design. We are currently in Mexico …relatively easy cruising grounds. Either sand or rocks….I will keep you posted.

Marek

Reuben Mezrich

Thanks again for a helpful article. Because of extreme paranoia I’m ready to switch out my Rocna (which has never dragged, but then I mostly cruise on the Chesapeake and occasional forays down the ICW to Miami). My simple minded question is what do I do with the Rocna. There doesn’t seem to be much of a market for used anchors unless I really mark it down. If I want to keep it as a spare, where do I store it on my Island Packet 380?

eheffa

These videos are hugely helpful but it is fascinating to note that there really hasn’t been a definitive comparative scientific study of anchors done by a neutral party to really answer the questions of holding power, scope requirements and resetting capabilities (in a variety of substrates) for the major anchors on the market.

This thread on cruisers forum is very informative: http://www.cruisersforum.com/forums/f118/photos-of-anchors-setting-126073.html

But, it really only represents a series of anecdotal reports.

The definitive study has yet to be done.

-evan

Clarence

Hi John,
A little more clear headed. A little more about our dragging event last evening. Island Packet 35 anchored in 15ish water. Rocna 25 with 100 ft of chain out. We hard set the anchor every time. We’ve been here a week and have ridden out several squalls without any issue. Last night, a squall line passed close. The outflow from the line blew approx 180 degrees from our resting heading. In hind site, what woke us up was a windscoop on a hatch inverted due to high winds making a loud racket. I then felt the boat surge forward. Not sure if we initially swung 180 or simply road over our anchor on our original resting heading. In any event, we dragged around 25 meters not my original estimate. A cat was anchored a short distance away. He may have also dragged a bit. We swung beam to beam without any noticible damage. The anchor did reset on it’s own and has held fine. The cat moved to a more open spot. From prior experience here, it is think mud. We usually need to use a boat hook to remove the mud, a pressure hose is not enough. We’re full time cruisers and this is the first time we have had an issue with our Rocna. While the initial gust was high and short lived, we’ve ridden out storms with much higher winds in similar bottoms. We carry a large Fortress as a spare. We see far too many boats drag. Biggest issue we’ve experienced in these waters is the mix of full keel, fin keel, motor boats and cats anchored too close, not understanding they all swing a bit different. We always ask our neighbors how much rode they have out. Too many don’t know or think if they have all chain, they can break the ratio rule significantly. Too many boats are not using snubbers on their short scope.

Paul Shard

I worry about a couple of factors in this testing.
1) he is testing a 33lb Rocna anchor rather than 40-50 class of the others. As he bounces back on the anchor the boat weight will have a greater effect on the lighter anchor putting the Rocna at a disadvantage. (since the boat force is similar but the Rocna is the smallest anchor)
2) he is setting the anchors at 3.5:1 and even 2.5:1 scopes and backing up at 3 knots

The test is worthwhile but does seem to be mainly testing one dramatic scenario. Resetting at a high speed with short scope. All round performance of any anchor is important, not just one scenario.

Aboard Distant Shores II a 49 foot Southerly we have a Rocna 33 (73lb) as our main anchor and it has been quite reliable. In our 7 years and 30,000 miles the Rocna has been excellent. From The Baltic to Northern UK and Norway, The Bahamas Caribbean and in between it has slipped only twice. (once in extremely soupy mud in St Martin Lagoon, the other time in grass in Denmark). Just recently our Rocna held both our 49 foot monohull PLUS also a 51 foot monohull that dragged on top of us in sustained 30-35 knots gusts. I would want to see more tests before giving up on this excellent anchor.

Paul Shard

Here is a link to our recent anchoring video showing the 33kg Rocna 50 feet down with short scope. We were testing shock loads banging back on the anchor.
https://youtu.be/w4qO_dIegaM

I would like to be able to test the Spade sometime. They look like a good anchor. You have obviously had good luck with yours.

SteveA

Hi,
It should be noted that the test was done at 3.5:1 scope. On the Rocna site 3:1 is stated to be the minimum, with 5:1 considered “appropriate”. Perhaps you would get different results if the designers recommendations were followed? That said, if another type of anchor will consistently reset at 3.5:1 is would be preferable. Maybe Rocna needs to teflon coat their anchors so mud won’t stick?

doug siddens

More questions
If the mud washes off and this allows the anchor to reset, what conditions promote washing off the mud: time, speed, angle to bottom, teflon ? And if reset occurs when the flukes near the roll bar are clean, then how do we understand the resetting at much slower speeds? Did the mud come off? When did the mud come off? Was the speed over the bottom a factor in resetting? Was time dragging a factor in resetting?
Revelations: 47 feet mono, ~50,000 pounds, 40Kg/88Lb Rocna

Dick Stevenson

Hi Doug,
If the Rocna is like the Spade, and I assume it is with regard to the loading up of bottom material, then it can be very hard to remove, often impossible without raising the anchor and manually cleaning it. We have a good wash down pump and still often need a boat hook to loosen the muck (possibly the only down side of these anchors). I suspect that it is quite unlikely either anchor would clean self-clean itself on the bottom.
Dick Stevenson, s/v Alchemy

Dennis

Hi
Started this year with upgrading our 20 kg Delta to a 25 kg Vulcan. We are now for 16 months full time cruisers.
The performance so far of the Vulcan has been excellent. We had however a situation where our fellow sailors quick action saved the day. Not onboard, sudden strong gust and the Vulcan failed to reset after dragging. It was well set and 4:1 scoop. We can’t however absorb this as the Vulcans fault since it happens in notorious Nidri bay in Greece, where the ground is so plowed up making it unreliable. Have however made us more on the watch.
Can so far recommend the Vulcan since it in many other situations have been proving itself when others have had problems.

Dennis

Anchor was set with 2/3 throttle and set directly.
However when reanchoring we had to have several tryouts in different spots before it was holding. Found out after that the ground was “broken” due to frequent anchoring.
Haven’t had that problem before or after and others did also have problems. So for now I consider it a exception. Will revert with updates if any.
Need however to say that the Vulcan have “saved” us from problems many times when others had problems.
And as someone wrote, there is no perfect all around anchor which is why your spare should be of another “kind”

Marc Dacey

This is my takeaway, too. We are thinking a SPADE (upped two sizes) and a big Fortress as the most “opposite mode of action” anchors we could have at the bow, but I will likely keep the real Bruce I have for the few types of bottom in which it seems to have a good track record. We may be approaching “peak anchor” in terms of all-arounder designs, and I still don’t buy a test that doesn’t include the full suite of variables. I don’t find them uninformative, just not comprehensive. Heck, Panope’s test of his child yanking a Bruce around a beach on a rope rode did demonstrate how it works.

Colin Speedie

Hi Marc

sorry – I missed your question.

We were anchored further out than many of the boats on both occasions, as if it’s busy and we can’t find plenty of swinging room we’ll move into deeper water to find it. We (almost) never anchor with less than 5:1 scope to an all chain (10mm) rode. We have 80m of chain spliced to 30m of 20mm octoplait in our main rode.

If we think the wind will get up we’ll veer more cable to say 7:1 and on the first occasion (from memory) that’s certainly what we had out. The second occasion came out of nowhere and we may have had 5:1 out. Otherwise, it’s a case of veering more cable in a hurry and we go to about the same scope. We have at least one snubber attached to a specially sited cleat in our bow locker that passes out through the starboard roller. We carry three of these, all with chain hooks.
These are all 18mm 3 strand nylon of 20m length.
We have anchored using the same basic set-up thousands of times with no problem.
But the conditions when we dragged were really extreme – sudden 180 degree wind shifts as the squalls rolled down off the hills. That was what caught us out on both occasions. The first time could have been really bad – we actually clipped the anchor cable of the boat we were on top of with our rudder while we were getting the engine going and preparing to haul the cable – a very close run thing. We motored upwind in blinding rain and anchored again – the Rocna bit first time, no problem. The second time we had loads of room and it was simply the case that we dragged for some distance, then held.
So we now always get up at a big shift and dig in again for the new direction. And very occasionally we’ve had to get the anchor up and clear the mud and set it again. We know the issue, so we deal with it practically.
And we’re ultra careful if we expect a front going through to move to the best spot to be ready for the shift. In fact we’ve just done so where we’re at anchor here in Nova Scotia. And we’ll be watching out when the shift comes through overnight. This isn’t difficult stuff – just the kind of sensible precaution that’s required.
Compared with the shenanigans I used to face before these ‘new generation’ anchors were available, it’s absolutely nothing at all….
Best wishes
Colin

Marc Dacey

Thanks for the informative reply, Colin. Anchors aren’t miracle machines, and you clearly have a Plan B for when the miracle doesn’t stick. Unfortunately, some of the most beautiful anchorages are often nestled between the sort of hills the wind likes to sledge down. Twenty metre snubbers? That’s impressive!

Dick Stevenson

Hi Marc & Dennis,
As to your comments as to the “spare” anchor being of a different kind to cover different bottoms, I am not sure I agree. A Fortress on the bow certainly can be used as a spare anchor, but I believe that most think of it not as a bower or even as a spare for the bower but rather as a kedge, for which it is ideal. Or as a spare anchor to dinghy out if needed, again an ideal anchor. But I would never consider it as a spare for the bower.
For years I had a spare anchor of a different type, a Luke, which I considered a storm anchor and (under duress) a spare for the bower. I sold the Luke a few years back and now have 2 Spades: one taken apart in the bilge and one as a bower. I no longer think of different design anchors being a wise strategy as bottoms differ. The Spade has worked better than any other anchor in a wide variety of bottoms I have used it on than any other anchor and if I lose an anchor I have a spare I trust. The Fortress is for easy transport in trouble shooting situations and (I believe) should not be considered a spare for a bower.
My best, Dick Stevenson, s/v Alchemy

Marc Dacey

Dick/John: Sorry if I misled with my comment: I don’t consider the Fortress at the bow as a “spare” so much as a lunch hook due to its ease of deployment and good holding with a mixed rode, a easier proposition for a stop ‘n’ go in appropriate conditions. I haven’t tested mine in anything tougher than straight-line winds of 20 knots or so, and it’s fine for that. Part of the issue in conversations of this type is the unsteady nature of the terminology; what has been deemed a “spare”, I would call a “secondary”, the anchor I would deploy were I to a) lose the primary or hit an unexpected bottom it didn’t like at all, or b) a second anchor for a two anchor set or a Bahamian moor. In the latter case, I’m not sure it makes a difference whether the second anchor is at the bow or the stern.

Colin Speedie

Hi Dick, John, Marc

on Pelerin we carry four anchors. Two Rocna’s (33 & 25kgs) a 30kg fisherman and a Fortress FX-23. The two Rocna’s are our bower and second anchor/bower back up. The fisherman we keep for kelp but quite honestly we think we might as well do away with it. The Fortress is a bit small, but is used as a stern anchor alone – where it works very well.

We have used Rocna anchors exclusively as bower anchors for over ten years now, both on my old working boat and now with Pelerin. We have spent literally thousands of nights at anchor with a Rocna. We have sat out storms at anchor in conditions where we would have been really nervous with an old generation anchor and have blessed the thing many, many times. During that time we have dragged twice, both times in extreme thunderstorms in the Ilha Grande area of Brazil. On both occasions this occurred after 180 degree wind shifts in 40-50 knots + and prolonged squalls. On both occasions we didn’t drag far, but the first time we ended up on top of another boat and had to shift and re-anchor. The second time was less serious, as we had more room. As a result we now have a policy of starting the motor and digging in the anchor again after a big wind shift. 99% of the time this works fine, but occasionally we have simply dragged the anchor with little resistance – and no, we haven’t been heavy handed with the throttle, either.

My guess is that when the plough of the anchor and roll bar are choked with solid mud the balance of the anchor is affected. I think that’s the most likely cause because there is little resistance to the boat’s movement, it feels almost like the anchor is simply sliding along on the base of the flukes. If that’s so, then surely the point is not in the correct alignment to dig in again rapidly. Of course, it might also be the case that the anchor is so choked with mud that there is some form of resistance to the passage of the anchor into ‘new’ mud. Without watching this underwater it would be hard to know.

I’d point out that in both cases where we dragged conditions were really extreme. I have no way of knowing how another similar ‘new generation’ anchor would have coped, but we’re glad that the Rocna coped as well as it did. I would never go back to any of the ‘old generation’ anchors if you paid me, as I know from many years experience that they are nothing like as good as the Rocna.

I agree with John that there are times when the Rocna may have an edge over the Spade – short scope, better holding power (perhaps) in soft mud, due to the huge fluke area. But equally there are times when the Spade (from all I have learned) will have an edge, too, notably in big wind shifts. Other anchors of the same style may have their advantages, too. But all of them can drag if thrown the wrong combination of circumstances – of that I’m sure. There is probably no perfect anchor.

Ultimately, the choice of a bower anchor should be down to being the best all-rounder. My guess today is that anchor may be the Spade. If we ever change our bower anchor it would only be to a Spade of the (approximate) same size. But we wouldn’t write off the Rocna which is an amazing anchor, and we’d certainly keep it as our back-up and number two, maybe number one in the right circumstances. For the moment, we know that we must take the extra precaution and dig it in again after a big wind shift, and we’d recommend the same procedure to anyone else who relies on one. Forewarned is forearmed.

Best wishes

Colin

Dick Stevenson

Hi Colin, John and all,
As to this discussion, I consider the short scoping attributes of a Rocna as far from compelling and in my anchoring world generally not an issue. I can think of no times this season where I would have wished for shorter scope nor did I reject any anchorage because I felt it would be too tight. In general, I suspect I would reject an anchorage that demanded short scope (either caused by land close at hand or a proximity of other vessels), because of the limitations on options if things heated up during the night. I think short scope is even less of an attribute if you have sized your bower to also be your storm anchor.
The other issue that would concern me is my mild, but palpable, anxiety when we leave the boat for long hikes or other excursions. Coming over the rise and seeing Alchemy bobbing safely at anchor after being gone all day is always a bit of a relief, especially when the weather has been unsettled. I rarely worry about the anchoring choices/situations if I am to stay on the boat, but know I am more concerned about the possibilities if I plan to be gone for long periods. It is then that I would really want an anchor that re-set without need for personal attendance.
Finally, I have been thinking and reviewing in my head, John’s comment that scope greater than 5-1 may be contraindicated because of the longer run-in distances possible in gusts and wind shifts. Although we have weather gale conditions on a 5-1 scope, I am clear that, given the opportunity, I let out more scope and have slept better for it. I suspect we “hunted” around a bit more with the additional length of leash, but not so I worried about it or even had it caught my attention. This may be as I use a very long and small diameter snubber (35 feet x 7/16 inch), but one could also argue such a light long snubber would contribute to flailing about. Bottom line, I like an increased scope and have noticed no drawbacks that concern me.
My best, Dick Stevenson, s/v Alchemy

Dick Stevenson

Hi John,
Bear with me. When I disagree with someone who I know to be thoughtful and experienced, I always like to clarify the details and usually learn something. My take has been that more scope is always better when it comes to keeping a boat attached to the seabed.
My experience in gale conditions with 7-1 scope is that when seas and gusts combine to rear the boat back, the chain gets pretty close to 2-blocked: stretched link to link, with some degree of regularity. This translates to the anchor receiving a tug. Many times, anchorage circumstances dictate that I do not have the option of more scope and I have been always been fine (knock wood). When the option is there, however, I have always let out more chain (maybe 10-1 or more) and felt like the boat was more secure. I have the sense that there is significant chain near the anchor that is never off the seabed anymore. Therefore, the anchor is little disturbed and what tugs it receives are at the best angle of attack, anchor to seabed. At this increased scope, the chain is never (at least in gale conditions) 2-blocked and so is providing catenary dampening of the forces as well as the averaging of forces provided by the snubber.
I believe the argument against higher ratios of scope is that the boat is on a long leash and can therefore have longer run-ins till it fetches up against the leash/rode and making a more forceful tug on the rode when it comes to the end of the tether. I believe this to be the case, but, it is my take that the added security of more scope far outweighs the added pressure on the rode as the boat has more latitude as it thrashes around. My memory is that with a longer scope, there was much less likelihood of the chain becoming 2-blocked when the boat fetched up and that the catenary (along with the snubber) softened the forces. Moreover, and maybe telling in itself, we were not at all bothered by any increased movement on the boats part as we lived our life belowdecks. On the contrary, I believe us to be more comfortable at longer scopes and more secure in general.
Now I realize that one can’t always find an anchorage that allows for longer scopes, nor are all blows predictable, but when planning for a forecast blow and the choice seems to be a coin flip between a more protected spot where scope would be limited vs a spot with a bit more exposure, but scope can be added on, I opt for the latter.
I look forward to your thoughts.
My best, Dick Stevenson, s/v Alchemy

Marc Dacey

This is a most fruitful discussion for us. Dick, you’ve said better than I could why 7:1 in a blow seems right to me in a way that 5:1 might (and I’m being careful here with the use of “might”) not. Our inclination is to avoid being too close to land and other boats and if the anchorage seems too tight on either score, or we know heavy weather and wind shifts might make it so, we would be inclined to stand out to sea rather than compromise on this point.

Colin, you can’t argue with success, and you’ve had mostly that, save for the two situations you cited. No doubt all credit to the Rocna on that score. You don’t write the nature of your rode (chain or mixed), the scope out in those extreme conditions, nor whether you have a waterline snubber or bridle on the rode , all factors I think, as Dick has pointed out, play important roles in that chimera of “ultimate holding power”. I would welcome your thoughts on Dick’s comment on those factors.

Rob Gill

Hi Dick, John,
As a Rocna owner, I have been following this chapter with interest and this sub-discussion on scope. I believe you are both right guys, “it depends”. If I may relate a long story (apologies in advance) to illustrate why:
Many moons ago I was a young Navigating Officer, on a 1200 foot ship anchored on a calm night in Wellington harbour (NZ), plenty of scope. I was writing up the log just before the change of watch at midnight. I observed the wind was getting up, maybe 15 knots. Nothing alarming, but never-the-less knowing the reputation of Cook Straight and Windy Wellington, I rang the engine room for immediate standby and the captain under his standing orders, but no answer from either – strange! I checked my anchor bearings. We were fine, but I noticed the bows starting to sheer-off in some building gusts. I rang the Saloon for the Captain, in case he was there. No reply – stranger still. By then the ship was skating around her anchor, the swings getting greater with every oscillation. Mild concern set in (or maybe a bit more)… I rang the ship’s general alarm bells 7 times rapidly… nothing. RANG AGAIN… still nothing. Ship’s alarms are really loud, at least 75dB(A) by law, usually much more. Was I suddenly on a ghost ship?
The wind was gusting harder, perhaps 30 knots and my anchor bearings were changing, slowly at first and then I didn’t need the compass to tell me. Still no captain, still no engine! Relief, the second officer arrived on the bridge wide-eyed. I thrust a radio in his hand with few words, one of which was “dragging” and the others unprintable. He disappeared towards the bow. I sounded the ship’s main fog horn, 3 short blasts – “I am going astern”…nothing! THEN SEVEN OR MORE BLASTS FOLLOWED BY ONE LONG (I should have been seeing people scrambling into lifejackets, or lifeboats even by then) – still nothing! We were dragging in a remarkably rapid and straight line astern towards an ugly lee shore – I didn’t have time to calculate our ETA.
Finally, finally, a white faced captain, 1st officer and half the crew arrived on the bridge together (no lifejackets). The engine room phone buzzed and I called for main engine power – took an absolute age. The second officer called on the radio from the bow, “do we want the second anchor”? Too late – the stern of the ship was now inside Evans Bay (lucky the wind knocks were more frequent than the lifts or we would have come aground on the point). We can see from the bridge directly along Oriental parade towards the city (have a look on Google Maps if you are interested). At long last the Telegraph buzzes, we plant it full ahead and motor over the anchor, no time for niceties and drag the anchor across the harbour to its previous position.
It turns out everyone was in the officer’s bar watching a loud movie – they didn’t hear the phone, nor the alarms (the alarm speaker having failed). The engineers were handing over their watch in the changing room – less said on that the better! How lucky was I? Maybe why I never win raffles.

But what I observed has stayed vividly imprinted in my mind, as is often the case in times of emotion (positive or negative). The wind gusts were veering and backing by 30+ degrees as they came out of distant and different steep-to valleys to windward of us (perhaps 50 knot gusts by the time we got control again, relatively normal for Wellington). This preceded the anchor break-out, as the ship sailed off its anchor following successive swings, each more violent. Even though we had anchored many times in similar wind strengths, I believe on this occasion we didn’t have the right setup for the combination of sudden load with repeated change of direction, working the anchor out of the bottom like a hook out of a snapper’s mouth. With hindsight I believe the scope was too short (there is no snubber on a ship and the chain catenary is the only shock absorber), but hey, I wasn’t making very scientific observations at the time.
From this experience, I see our priority is to avoid the situation where the boat/ship can shock load our anchor from repeated and different directions. For some boats this may be mitigated by increasing scope, for some it may be limiting scope – I suspect each boat / ship will be different and even alter with conditions. Our current yacht seems to respond well to increased scope of chain (even 10:1) and a bridle from both bow fairleads (rather than single line snubber), but we haven’t been in any extreme anchorages.
Rob

Dick Stevenson

Hi Rob and John,
Fascinating story, Rob. Especially with the good ending. Thanks for sharing.
As an aside, what a good example of how often it is a confluence of small events: broken alarm, loud movie, change of watch, which contribute to the making (almost) of a single disaster.
More to the topic; clearly the veering about in gusts was deemed to contribute in some large measure to the breaking out of the anchor and subsequent travels along the harbor. I think those with too short scope (as you felt was the case for your ship) for conditions often have their anchor break out in just the way you describe when a combination of seas, gusts and veering- about yank the anchor loose from the seabed. On the other hand, I have yet to hear reports of recreational vessels who felt that an anchor break out was attributed to scope that was too long (allowing for increased shock loads as there is more momentum built up because of greater distances traveled between gusts). I do believe that there is an increase in shock loads and momentum, but believe that the increased scope more than compensates, much more. Bottom line for me, with all the data and calculations you mention, I just do not hear, read or find reports of recreational vessels breaking out their anchor with greater scope ratios and attributing it to the increased loads referred to. Breaking out with short scope., for sure, longer scope break out is just not on my radar screen.
I very much agree, with usual anchoring scope ratios (5-1 to 7-1 or so), that chain catenary is an illusion when it comes to weathering gales. And I also agree, Rob, that boats lying to a 10-1 scope behave quite well (designs good for ocean passages probably do better in this regard), even when things get boisterous. When increasing scope to 10-1, it has been my observation that chain catenary does play a role in dampening forces (in gale conditions and along with the snubber) and as the ratio increases, the more of a role chain catenary plays in averaging forces. And this is one reason I increase scope over 7-1 when conditions warrant and opportunity allows.
I think it is always an issue being too formulaic and simplistic: ie, more scope is better. That said I look to reported evidence that more scope causes/contributes to anchor break out in either my own experience, reports in the media or shooting the breeze on the docks, and have yet to find any. Quite the contrary, most sailors, experienced or otherwise, first reaction to things heating up is to veer more rode. Now, I am far from saying that one’s first reactions are always the best, but there is a lot of history and experience behind this reaction.
My best to all, Dick Stevenson, s/v Alchemy

Rob Gill

Hi Dick – Your last comment on first reactions and scope reminds me of the apocryphal story of a young trainee up for Maritime Board oral examination: Examiner (usually a “grey-bearded” Extra-Master Mariner) – “You are at anchor young man, the wind backs and increases to force 6. What would you do”? Trainee – “Why, I would let out more scope sir”. Says the examiner – “Ok good, the wind is now force 8, what will you do”? Trainee – “let out more scope sir”. Examiner “Ha, you are running out of options lad. It’s now storm force 9-10, you are dragging, what to do eh?’ Trainee – “Let out more scope sir”. Examiner – “where are you getting all this blasted chain from young man”? Trainee – “same place you’re getting all the wind from sir”!!
Rob

Richard Dykiel

Because my bowsprit wouldn’t accomodate the rollbar of a rocna, I chose a SPADE on your recommendation for my Dana 24. Glad I did. It cost less than 1% the price of my boat, so I find it amusing that anyone would consider the price factor when buying an anchor. It’s not like you’re going to buy it many times, right?

I had a rocna on my previous boat (catalina 30) and was satisfied with it (inshore sailing east coast US). Only once did I drag, and then very slowly: because I was foolish to anchor off saquish neck in at the entrance of Plymouth harbor, an area with very strong current in a deeper channel. I’m assuming the current moves the soft sand. The anchor was fighting good and the dragging was slow. Not sure a SPADE would have been behaving better in these circumstances.

That said, it seems the body of evidence points to the SPADE being the best choice these days. IMO you should always select the best ground tackle, even if you’re not a full time voyager.

Conor Smith

Other people have mentioned it, but this important point should be emphasized!

The Rocna 33lb is being compared to the 33 PERCENT HEAVIER Spade 44lb. Thirty Three Percent!!! In John’s own words in a previous chapter, “bigger is not just better, it’s a LOT better.”

To me, it seems discriminatory, to allow such a biased test between anchors to radically change the recommendations of the author (whom I have a ton of respect for and love learning from).
Just looking at the Mason Supreme and Rocna tests, we see evidence that supports the theory that mass is critical in these tests. They are nearly identical, except the Supreme is 36 percent HEAVIER than the tested Rocna. It sets every time. Coincidence, maybe, superior engineering, maybe, but definitive test, certainly not.
And if you ever needed evidence of the spade failing, look at the earlier comment from Geir ove, who posted a video of a spade sliding in the mud. Proof that perhaps all anchors can and do fail at some point.
Although you have stated you have heard reports from other sailors of their Rocna failing, it seems that this video is the catalyst to change your recommendation, and to me, that seems unfair, until a proper test with equal weighted anchors, is performed.

Marc Dacey

Conor, while I certainly acknowledge the validity of comparing “like with like”, please consider that with its lead-weighted tip, the SPADE isn’t “like” in that sense. My understanding is that in terms of fluke area, it’s smaller than the Rocna. The lead in the tip has to form some of that extra weight.

Were a Rocna versus a Manson or even a CQR being discussed, the “like with like” equation would be satisfied. The SPADE’s lead tip, however, would seem to be key to its ability to orient well and bury quickly. That’s a qualitatively different approach than the quantitatively different observation you’ve made. The now-old-news Rocna metal-grade issue aside, I have no doubt it’s a very good design, and one that is now largely proven in the field. But that doesn’t make it without potential flaws, none of which may ever arise in your own sailing grounds or anchoring style. But some of us are looking for as comprehensive an anchor as we can discern, even while acknowledging that it, too, may drag under unusual conditions of ground, wind or current. Discussions like this one, particularly where there’s a high degree of offshore and distant anchorage experience, get us closer to that sweet spot.

Conor Smith

John, Marc,

I think I under-appreciated how much you put your neck on the line, in the first instance, making a gear reccomendation to readers. So I understand more that, out of prudence, you want to remove any recommendations while contrary reports are starting to filter in.

I think we can all agree we would love to see a 44lb Rocna tested by Panope in the same conditions.

Marc Dacey

I know that comparing a Rocna to a Manson Supreme will provoke bun fights, but I found this Panope test interesting: equal-weight Manson vs. SPADE. The phrase “ridiculous scope” comes up: https://www.youtube.com/watch?v=giDsoDHxG_c

John Lubimir

John-
In the anecdotal, FWIW Dept., I would agree with Dick Stevenson above regarding scope. I would also agree that price should not be a deciding factor in ground tackle selection. We switched from a marginally effective 110lb CQR to an 88lb Rocna on our Able Apogee 58 (8′ draft, 52,000lb+/-). We consistently use 7-8:1 scope when initially anchoring and have never suffered any adverse issues with more rather than less scope and a 25′ snubber. (Often, after a power set with our normal scope, tight anchorages have required a more courteous 3:1 scope.) While I respect your video results, 2.5 -3.5kt speeds with much less than recommended scope represent the typical bareboat charterer anchoring method, not the seasoned cruiser’s approach (amusing until they anchor near you). We tend to deploy our all chain rode at approx. 1-1.2kts, allow the anchor to settle for a minute or so, then hard set to 3000rpm for a min. of 30 seconds. In over 150 nights on the hook with the 88lb Rocna in New England, Florida and the Caribbean (and hundreds more on a 46′ sloop with a 66lb Rocna from the Great Lakes to Nova Scotia and the Florida Keys) , including reversals in 40+ knot frontal passages and in many areas between islands where a 180 degree 2-3kt tidal current reversal is the norm, we have only dragged twice. In both cases it was “user error” as a result of being in a hurry. I have dived on the anchor many times after a CF passage or tidal reversal and been amazed that, in a variety of bottoms, the Rocna has reset in just a few feet without breaking free. While the Spade is a great anchor, the tests haven’t convinced me that a properly set Rocna with maximum allowable scope and a good snubber isn’t just as effective. Anchoring technique, inattention to the composition of the bottom and failure to visually verify the set (visibility permitting, we often use our dinghy and a clear bottom bucket) appear to be the largest contributing factors to boats dragging, even in relatively benign conditions.

Regards,
John Lubimir
s/v Patriot

eheffa

Thank you John.

I appreciate your insights and you sharing your experience.

This whole issue has had me feeling a little spooked & it’s good to know that with decent technique the Rocna may still be a viable option for our primary anchor. We are not offshore cruisers but in our home ‘turf’ of the West Coast around Vancouver Island and North Coast, many of the anchorages are subject to significant tidal currents and reversals. Mud bottoms in waters not conducive to diving mean that we are always left wondering as to what our set really looks like and whether a reversal will result in a sudden drag. I don’t like the thought that we cannot rely on a well-set anchor to stay that way. We have a Rocna 25 kg on a Nordic Tug 37 (40′ LOA & 22000lb displacement). We have not yet had it drag even in some rather stormy / reversing conditions but with rocky inhospitable lee shores as the norm, there isn’t much room for a sudden loss of holding.

I would be willing to swap out the Rocna if necessary but probably need to do some of our own experimentation before we consider it to be an unreliable bower.

– evan

evan

I realize that this is an old thread now but thought I might report back on our experience…

I had one occasion when anchoring with our Rocna 25 Kg anchor in Prideaux Haven in Desolation Sound. I chose a very scenic location in a channel between some small islets with fairly strong tidal currents. Overnight, strong winds in the 25 + knots sprang up and supplemented the force of a 180 degree tidal current change. Out of the blue, the anchor alarm started sounding at 0200h. I jumped up to see that we had indeed moved a good distance from our original set; but, over the subsequent tense couple of hours in the streaming rain and wind I was reassured to see that we were no longer moving. We were nevertheless uncomfortably close to some rocky bluffs. The next morning, we moved the boat to a slightly less scenic but more sheltered location.

In this case, I am quite sure that the anchor had dragged and reset with the tide change.

The SV Panope videos would seemingly support the possibility that the Rocna may release and have trouble re-setting. Thankfully it re-set for us but it took something like 25 – 40 meters to do that. We were close enough to the rocks when it re-set that any more movement would have been disastrous.

We subsequently replaced the Rocna with a Spade 120 and have noticed that the Spade definitely sets more quickly and reliably. (My wife, a nervous soul, often comments on how reassured she is by the hard definitive set with the Spade.) A number of local anchorages where we could not get a set with the Rocna (weed bottoms and thin mud) have been no issue with the Spade.

We also find that when raising the anchor the distribution of the mud on the Spade is on the tip and not the back of the flukes as it was on the Rocna.

My only criticism of the Spade would be that much of the yellow paint was peeling off when new and after ~ 75 – 100 anchor sets, the galvanizing is abraded off in a few places: on the tip, one spot on the dorsal surface of the shank and at the eye where the shackle attaches to the anchor. We are seeing rust blooming where the galvanizing has been lost. (I plan to spray these areas with galvanizing paint.) I do think that the galvanizing could be better applied than it is…

That quibble aside, we are very happy with the Spade and happy that we made the switch.

-evan

Charles L Starke

Hi John
I just heard of an interesting trick that the schooners in Maine sometimes use for storm anchoring. They drop an anchor in a deep hole (one near here on Vinalhaven is 140 feet deep) and drop back to a water depth of 10 feet. That way, an anchor dragging has the chain and anchor dragging uphill for its whole length. Scope is way more than 10 to 1 and there is minimal skating around on the anchor.

Marc Dacey

I like that idea!

Dick Stevenson

Hi Charles,
Anchoring uphill such as you describe is pretty common in the Med, especially around Turkey, when combined with tying off to shore. The depths are such (and the prevailing norms) that free anchoring is often not a wise choice. With the right bottom, one can achieve impressive holding with little scope, especially when the winds get sideways and the forces multiply dramatically.
Always fun to hear what the big boys do.
My best, Dick Stevenson, s/v Alchemy

Alan S

Hi John,
in your opening story you mention about a yacht being lost in Greenland and seem to infer that it was Rocna equipped.
The yacht concerned was Arctic Tern 1, and as can be seen in the picture was fitted with some form of plough anchor (I will not say CQR), and it was this anchor and another similar one that failed to hold her;
comment image
The replacement Arctic Tern is fitted with a Rocna, per
http://northwestpassage2014.blogspot.cl/2014/09/sv-arctic-tern-uk-arrives-nome-alaska.html#!/2014/09/sv-arctic-tern-uk-arrives-nome-alaska.html
so it would be best to amend the appropriate paragraphs
cheers
Alan

Alan S

Hi John,
the story you tell appears to be entirely consistent with the events resulting in the loss of Arctic Tern 1 and rescue of its crew.

Drew Frye

Lots of good discussion.

I invite anyone who believes a “definitive test” should be run tell us how to do that and then get involved. I’ve done a fair amount of instrumented anchor and rigging testing, and to say you are “herding cats” when looking at the data is to put it mildly. The number of variables, and the extent to which they matter is just mind blowing. There are good reasons the “testing” is nearly always in sand and in a straight line.

Soil mechanics. At what rate does density increase? Is it sandy or cohesive (clay)? Are there layers?

Depth of set before veer. An anchor on the surface will rotate nicely, a little deeper it may just pop out, deeper yet it may not budge. Each situation has very different mechanics. How much veer? And again, soil type matters (does it stick?).

Rocks and weed. Is the bottom consistent, or is hooking and scraping ability critical?

Effect of size. Almost direct proportion in consistent sand or mud over a range of 100x. But that is only in a straight pull (smaller anchors can actually be better in a veer sometimes, because they are set more deeply). Weeds are different. In rocks the smallest anchor might get in the slot better. Unless they are rounded, and then weight matters.

Did you dive on the anchor, both after initial set, and after the storm passed? Were you down there during the storm? If not, you don’t really know what went on down there.

All I can say is “good luck” to you. The work is interesting, exhausting and frustrating. And this is why a large collection of anecdotes, with extra emphasis on really understanding the failures, is vital. Successes are much less important, in a way, since you can never tell what the anchor might have snagged.

Drew Frye

And yes, in testing, I have seen practicably every anchor jammed with clay or sticks and weed such that it could not reset. Frighteningly common, actually.

However, I have not tested SPADE. No good reason, just didn’t have one available to me.

Brian

An excellent and important discussion. Drew’s extensive anchor testing is certainly noteworthy and of great value to the conversation, as are the comments from those who have extensively battle-tested their anchors under many different conditions.

Here’s a few additional thoughts:

– Take two anchors of identical weight. Pay out the same initial scope for setting, and then load them to 3,000 rpms of engine power, as per Steve / SV Panope’s tests.

– The anchor which buries the deepest and/or compresses the most bottom sediment to its fluke (and performs as designed) is going to perform the WORST when it is flipped over at 180° degrees, as done during these tests.

– This is because the better performing anchor during the initial setting has to break free from the deeper penetration AND shed the compressed sediment before it can re-engage and re-embed into the sea bottom.

– Now on to the Rocna vs. the Spade. I have both here at Fortress from the Chesapeake Bay testing, and they weigh the same, 44 lbs (20 kg). It is obvious that the Spade has a much steeper angle to its fluke, and the Rocna fluke is flatter by comparison.

– Additionally, it appears that the Spade fluke has less surface area, which might allow it to bury deeper during the initial setting than the larger Rocna under the same load (3,000 rpms as per Steve’s tests).

– However, the smaller and steeper Spade fluke would likely have an easier time shedding the bottom sediment if it was flipped over during this 180° test.

– Additionally, you cannot overlook the possible effect of the Rocna’s rollbar during any testing. While sediment would likely pass through or over the Spade’s fluke while under load, it is possible that the rollbar of the Rocna would restrict and compress the sediment, which in turn might make it more difficult for the anchor to shed the sediment and re-engage the bottom.

– The 45 lb (20 kg) Mantus anchor was given accolades for its performance during this testing and I think that might be because of its very flat fluke (definitely flatter than the Rocna or Manson Supreme), and I suspect it simply did not bury as deeply during the initial setting under 3,000 rpm of engine load, so flipping over and not re-engaging the bottom was not a challenge.

The Mantus also has a roll bar, but it is huge compared to the Rocna and Supreme, and it is hard to imagine, although certainly not impossible, for sediment to get collected there.

Drew Frye

I believe one of the other Practical Sailor testers is going to tackle break-out force vs. type and depth soon, though I wouldn’t expect results to be published for 9 months at least. We are still discussing which cases make sense to study.

The motivation is to better understand the behavior of anchors like Fortress that are very secure when deep, but not so much when shallow. We wonder if smaller anchors that are well-set might sometimes be better than oversize anchors that are not fully engaged due to lack of engine power. I think it should be self-evident that any anchor can rotate to meet the force when very lightly set (that’s what happens when we deploy. We also know that in light winds the anchor does not rotate if well set; it doesn’t need to and isn’t forced to. I know that I often set my anchor to the west in the summer (that’s where squalls come from) even when the prevaling wind is light and south.

I repeatedly anchored in rocks and on hardpan this summer, diving to see what was happening. All of the rules are different. Sometimes I was just as secure with 2 x 2-pound anchors in-line as with 1x 35-pound anchor; the anchors never actually set, they hook. That whole area deserves more investigation. I know I learned a lot that wasn’t in books. Anyone who wants to get smarter about anchors needs to dive more. And it doesn’t have to be 80F and clear; all of my experience is in cloudy water, and sometimes quite cold.

As for SPADE, I don’t comment because I don’t know. But everything I see tells me you are right. Just for fun, I cut the roll bar off a Mantus dinghy anchor. Unless you are a complete clod, it lands butter side up 98% of the time. And unsurprisingly, without the rollbar it is much better in debrise-laden mud. No clogging. It seems folks are trying to come up with non-rollbar designs, and someday there will be new wrinkle. Personally, I’m amazed that anchor design wasn’t finished 100 years ago! It seems so simple, at first glance.

Brian

Drew, agreed and as you well know, trade-offs are almost always a certainly with anchor design.

I was reminded of this awhile back during a discussion with our consultant who worked with the US Navy and the offshore industry as a soil mechanics and anchor design expert for close to 50 years.

He told me that they had replaced the “high efficiency” 100 lb steel Danforth anchors for the Navy’s Underwater Construction Team (UCT) boats with a much beefier 100 lb Navmoor that he helped design because the Danforth anchors kept bending the shanks.

The Navmoor anchor would not bury as deeply as the Danforth and it had a thicker shank, which allowed it to turn better (but still remain engaged in the bottom) during wind or tidal shifts.

I look forward to the upcoming Practical Sailor study.

Gerben

John, maybe you could replicate Steve / SV Panope’s camera rig and do a few of his re-set tests of your own with your Spade, and maybe with a Rocna. (“Reproducibility is one of the main principles of the scientific method.”) Verification of falsification would be the result…

doug siddens

Driven by possibly looking to “defend” my choice of a Rocna, my thoughts have been looking for openings in this discussion. However, I’m not brand loyal.
Let me state my assumption, most imagined by the videos offered, that the failure of the Rocna to always reset in a strong and sudden wind shift also includes the boat going directly over the top of the set anchor.

If this is a shared understanding, I wish to introduce a variation: that the boat does not go directly over the anchor but swings about it describing some length of radius. How might this be different from the aforementioned?

There are still the effects of that pesky mud to examine and how build up on the flukes interacts with other variables to bring about failures of resetting.

Eric Klem

Hi John,

This issue with reports of Rocnas failing to reset has been bugging me as well recently. I have never heard the same complaint made about a Spade although I don’t know if Spade has the same market share. Like all things anchors, most of the time the loads are so low the anchor will not have to reset during a windshift so you need an enormous sample size to figure anything out. However, you should design for the 40knots which did a great job of testing resetting/veering ability. I believe that anchors, like everything else, are compromises and that we need to pick the best one for the way we are going to use it because after all, we use an anchor to try to stay in one place.

We cruised on a Rocna for many years and it was the best anchor that we had used to that point with no failures once set. We also own a Manson Supreme which one time allowed us to move rapidly backwards about 20′ as the wind veered in a tropical storm and I have never determined whether it was due to the chain being caught on a rock on the bottom before freeing itself or the anchor actually moving backwards. I have never owned a Spade but I have used them to a lesser extent and my experience suggested that smaller Spades don’t set as well as the larger ones and small Rocnas but that the big Spades are great. If it were not for these issues getting a good set in a few different places with a smaller Spade (admittedly a single anchor but a brand new one that had not been tampered with), I would come to the same conclusion as you and simply recommend that as the way to go. We now cruise with a Mantus which has been the highest performance of the 3 in our experience but also is likely the least durable. For smaller boats not cruising in really rocky places, I would probably choose a Mantus knowing its durability limitation but trusting it to always set and for larger boats, I would probably choose a Spade knowing that it doesn’t have quite the same short scope performance as the Mantus but is otherwise excellent.

I suspect that the hypothesis that material on the fluke causes the tip weight to be too low may be right. When we were cruising with a Rocna, we noticed that it took longer to set if we had not cleaned the material off the fluke. With our current Mantus, it seems to be much more resistant to this although it has a much higher percentage tip weight. The only time the Mantus failed to set on the first try, we had a fair amount of material on the fluke, it was a very grassy bottom and a guest was running the windlass and did not pay out chain fast enough so we dragged the anchor around in the grass for quite a while before it had even 2:1 scope. Whether the material on the fluke contributed, I cannot be sure.

It would be interesting to measure/calculate tip weight on the different anchors then get impacted material on the flukes and then measure/calculate the new tip weight and see if it is significantly different. In the Panope videos, he measures the tip weight percentage which is great and a good first step to understanding how much it can be affected.

I think your recommendation to reset the anchor after a big shift is a good one.

Eric

Marc Dacey

Eric, I am curious as to your comments on the perceived durability of the Mantus design. In what respect do you find it less durable than, say, the Rocna or the Spade?

Eric Klem

Hi Marc,

The reason that I believe it to be less durable is that I believe it can generate larger forces on less-strong sections. It is physically a bit larger than a comparable Rocna which means that if you are twisting it or doing something similar, it should have more resistance from whatever it is set in/fouled on leading to higher loads. Additionally, the shank is a lot longer so the same force applied to the chain will result in higher bending stress. I have only seen a bit of data comparing sections but I believe that the geometry is smaller generally and they try to make up for it with high strength steel. Mantus actually has a section on their website devoted to shank strength and they find that their shank is less strong than that of Rocna, Manson Supreme and the steel Spade although still stronger than a lot of other anchors.

In the end, what matters is that we stay where we started. I am only aware of one Mantus yielding which was one of the early ones with a low strength shank in storm conditions and well documented on cruisersforum. The amazing thing was that the anchor appeared to continue to work reasonably well even after this issue. It is my belief that the chances of bending part of the anchor mid-storm and having it pull out are lower than the chances of a less high performance design dragging. Therefore, I believe this design to be the best for our needs provided that we understand it is not as rugged. We carry our old Manson Supreme as a full backup (and a fortress) but if we did not have the Manson, I would absolutely have a second identical Mantus especially because they are so easy to stow. Lets face it, you can bend any anchor in the right circumstances but these are also really rare circumstances so we should be aware of the possibility but not blow it out of proportion. If we had a Spade which has the strongest blade and shank, I would still carry a backup primary to deal with potential damage or loss.

I know some people have worries about bolts, simply put, I don’t. If you take appropriate measures to keep preload on the bolts so that they don’t loosen, they can make an incredibly reliable connection, often more reliable than welding.

Eric

Marc Dacey

I concur on bolts (of the right grade of steel and with decent Nylock nuts, etc.). Thank you very much for your considered and informative answer. I hear good things generally about the Mantus, and it’s refreshing that they themselves note this factor. Very few people who anchor will experience conditions bad enough to damage the anchor in its chosen ground (hooking on heavy debris or in unlucky boulder cracks aside), but it is a a factor in the full appraisal of the suitability of one design over another. This is probably the most fruitful (and most polite!) anchor discussion in which I have ever participated.

Dick Stevenson

Hi all,
A couple of questions regarding Rocna: with a Rocna down and after a significant wind shift you seem to have re-set: would it be generally recommended to raise anchor, clean it and re-anchor? Would the shift being slow and gradual vs fast and stronger winds make a difference in this decision? Would first backing down hard (before raising and cleaning) allow enough confidence so raising and cleaning would not be recommended? Or would confidence only be restored if anchoring with a clean anchor and pulling from one general direction?
Being aware of Rocna’s need to be cleaned off and re-set after a significant wind shift is of concern for all the obvious reasons. One concern, so far unmentioned that I noticed, that just occurred to me is that one loses the precedence of being “first anchored” and the privileges that come with that. I pay attention, in crowded anchorages or where there are behaviors I am uncomfortable with, of the order of boats being anchored and even, although rarely, document same in my ship’s log. I am more likely to document if expecting a squall/weather etc. and the wind shifts that often accompany same. Losing a “first anchored” position might only be annoying, but at times could be more important.
Thanks, Dick Stevenson, s/v Alchemy

Colin Speedie

Hi Dick

Good question.
Whenever we have a big shift we re-set the anchor (Rocna 33). We do this steadily (if possible!) and then once we know we have the chain straight in the new direction we want it to lie, then (with one eye on the sounder – we ease more cable first if the ‘new’ depth demands it) we put the power on try to dig the anchor in again. Generally this works fine, but occasionally we have failed to re-set and then there’s nothing for it but to lift the anchor, clear it and try again. So far this has never failed.
I agree that it’s a pain in the neck having to shift and maybe lose your spot, but compared with dragging into some innocent soul or piling up the beach it’s a small price to pay! But I avoid anchoring in crowded spots in any case – if I can – and have been lucky so far, although the time we dragged in Abraao, Ilha Grande, Brazil was close – too close….
Best wishes
Colin

Rob Gill

Hi Dick,
A quick comment on your thought of losing a “first anchored” position and “privileges”. This is an honourable concept well enshrined in the etiquette of boating and mostly well observed.
However, in maritime law there is no such “pecking order” covering two anchored vessels and they would be given equal status (and have equal responsibility to avoid collision) like say a vessel “not under command” and a “vessel restricted in her ability to manoeuvre”. Such a situation is not covered by any rule in the “International regulations for preventing collisions at sea” that I have read. But I have heard similar comments recounted enough times that it seems a reasonably common and possibly dangerous “misconception”. I believe the only “precedence” covering collision or loss of vessel(s) with both at anchor is marine case law, which puts the onus on any skipper or master, concerned about a situation, but then electing not to act to mitigate the perceived risk. I even think the unfortunate skipper/owner in this situation may find their insurance cover tenuous, as policies often require the owner to make every reasonable effort to avoid risks to the vessel and crew.
You are probably across this Dick, but I thought it worth pointing out. A few seasons ago we were finishing drinks in the cockpit of a neighbour’s yacht when a racing yacht came in, and anchored almost on top of us with dubious scope. The whole crew then jumped in their dinghy making for a party on a distant beach, all the time the wind was strengthening and dusk arriving. Somewhat bemused, you can imagine there was discussion about what to do and who should do it!
For clarity, I am in no way condoning the selfish/careless behaviour by the latecomer, nor inferring “no fault” on their part. Happy to stand corrected if things have changed since I took my ticket!
Rob

Dick Stevenson

Hi Rob,
Understood and agreed. You clarified nicely what I suspected. I also suspect that, over the years, there has to be some case law that has arisen from boats at anchor damaging each other, but I do not know of any. As maritime law is largely quite reasonable (to me), I would hope and expect that there would be some recognition of common custom and practice such as “first anchored”. This would always give way to the skipper’s requirement to avoid collision, of course.
My best, Dick Stevenson, s/v Alchemy

Rob Gill

Hi Dick,
Good observation about marine law being reasonable, I agree. Though I believe that such “reasoning” would put the onus first and foremost on good seamanship (not perceived privilege or custom), and so any skipper who is concerned with a situation would be expected to take action to mitigate such a risk, however unfair or inconvenient.
To illustrate, as a 17 year old trainee I accompanied the second officer and crew in a wooden ship’s lifeboat to politely ask a Greek coaster that had anchored on top of us in Piraeus Harbour to “b—– off”! Unfortunately the gravity of our request was somewhat spoilt by the fan on our air cooled engine scooping up sea water (rushing in through the gaps in clinker planks dried out in the Mediterranean sun) and sending it as high as their bridge wings and soaking our uniform “whites”! The Greek captain was most amused that we were apparently sinking in our lifeboat, and utterly unconcerned with his clear and obvious proximity to our ocean going vessel. Some time later, back on our bridge reporting to our captain the lack of success in communicating “customary” privilege, the captain gave orders to weigh anchor. Sensing my indignation, he explained that he was the concerned Master, and so we must move before nightfall. As the first fathom of chain hit the locker, the Greek “upped and away” with a mock salute (and a great story to share over an ouzo).
That said, if after a collision it was found neither skipper was concerned (perhaps unaware of any pending risk) then blame could be expected to be apportioned equally. But if one skipper was then found to have not taken proper duty of care (such as leaving their vessel unmanned to go to a party ashore) then I would expect blame to be unequally apportioned.
Kind regards, Rob

Michael

I found the testing to have several flaws and all are due to scope and depth. First I must disclose that I am a Rocna fan and have a 25k or (55lbs) as my main anchor for my Catalina 42. I have almost four years and 19,000nm of South Pacific cruising including circumnavigating Tasmania last February- March. My Rocna has never failed me in all that time, I have heard the stories about failing to reset but have no personal experience regarding that, and always backdown hard to set the anchor in the direction I think best.
I have learned that I can anchor in deeper water with 3-3.5 scope but also know that shallow water demands more scope, I think most of the salty dogs on this site will mostly agree with that general rule. I think the conditions of the test , 3.5 -1scope, 2.5-1 (!) scope in 25 ft depth are troublesome. The 2.5 scope is a worthless test! Would I consider using a 3.5 -1 scope in 25 ft , not likely. If I expected 20kts + , I would have at least 5-1 scope. I also don’t think that driving 180 degrees over your set at 3.5 Knts at a 3.5-1 scope and the anchor drags proves anything. Show me that same test at 5-1 scope in 40 ft. Yes I pull up mud and/or sand all the time and will motor slowly for bit wth the hook just in the water to clean.
If there is a take away from this flawed test, it is that a rapid 180 degree shift in strong winds or heavy current is problematic and if it ever happens, I will be on deck.

Colin Speedie

Hi Michael

good points. Apart from the extreme events I’ve outlined in earlier comments our Rocna’s have performed flawlessly in over ten years of working boats and living aboard. But your final point is the key one, and is now our mantra, too.
Best wishes
Colin

Michael

John,
Your evidence is compelling and you’ve done us cruisers a great service by identifying this weakness in the Rochna Design.
As you make discern from how us Rochna lovers will not easily give up the “anchor love of our lives”, much like an old friend or crewmate who has been through thick and thin and never let you down. While I have swung 360 degrees or more on my Rochna, I have never experienced it dragging. I will continue to use this most amazing anchor and thank the lucky stars and “Mr Rochna” for the gift that the Rochna Anchor is to me and boaters everywhere.
Fair Winds and Safe Anchoring,
Michael

Norm Facey

An Experiment in tip weighting
BACKGROUND
Cruising across the South Pacific in a boat that took too long to build had us working with aN 80lb plough anchor – it was the predominant design of the day when I started, and with a bowsprit, bobstay, and substantial bow roller designed specifically for a hinged anchor (the flukes actually pivot around the bobstay as it self stows), means switching to any modern design requires cutting/welding/sandblasting rework that is simply daunting away from my home work shop.
The plough worked well in the limited anchoring we did prior to departing home waters, but once out cruising, showed a tendency to drag in 25+kt winds.
With few real options, we managed across the pacific using greater scope, snubber, and anchoring downwind of other boats. Routinely used drag alarm, and occasionally re-anchored in the dark.
When we reached New Zealand, I bought a well rated Excel as being the closest reasonable fit, and tried it out. It worked, but was a bear to stow safely (raising anchor in big waves would be a real challenge).
I decided to stow the Excel for a season, and try reworking the plough to improve it’s performance.
THE EXPERIMENT
Comparing the plough in hand vs modern designs;
– it was heavily built; strength is not an issue
– fluke area was close to the Excel – even the angle isn’t far off.
What stood out (aside from the hinge) was the relatively blunt tip, and lack of tip weighting. So I had a more aggressive tip – sharper, over hanging downward (think hawk’s beak) – fabbed and welded on, boxed the bottom in with steel plate, and then poured 10lb of lead into that hollow.
RESULTS
It doesn’t set as hard/ fast as a Rocha (which is the predominant anchor we see in the cruising fleet), but it sets, holds, and resets reliably. We now anchor comfortably in crowds and more constrained anchorages, with an anchor that easily self launches and self stows. I expect the Excel will remain in the bilge for the balance of our voyage.
THE POINT (haha!)
Tip weight and configuration is critical to consistent anchor performance.

Marc Dacey

Norm, I like the initiative you took to alter an existing design. Apart from the labour and time, there’s little to lose and much to gain from such an experiment, and, had it failed in practice, you had the Excel in hand.

Now you’ve got me thinking about my old, on the verge of going on the scrap heap CQR!

Dick Stevenson

Hi Norm and all,
BS (before Spade) back in the mid aughts, I became so frustrated with my CQR failing to penetrate that I took a grinder to the tip and sharpened it. The work was a major PITA (that metal is hard) and the result made me feel good, but overall failed to make much of a difference in setting the anchor.
TGF new generation anchors, Dick Stevenson, s/v Alchemy

Chris Connor

I enjoyed the testing and resultant discussions.

I admit that I have not read through every comment but one question I have is how exactly was the camera rigged? Could the drag of the camera, line and floatation have impacted negatively by being attached to the roll bar thus preventing the tip from penetrating the bottom?

Regards
Chris
SV CORONATION
Gozzard 37

Joris

Hi John,

We are just on our way home from a year of cruising in the Caribbean. Having a physics background I fully buy the theoretical advantage of the spade over the rocna (still in a deserted place in South Spain I was not able to watch the video unfortunately). In fact I already believed the spade to be the slightly better anchor about a year ago when we decided to buy a 20kg Rocna for our Westerly 33.

So why didn’t we buy a spade? Because:
1. Rocna’s are very good anchors and a huge improvement over the old CQR we had. They made me sleep comfortably all year.
2. We don’t anchor much in high lattitudes where windshifts with strong winds are more common.
3. We never leave the boat alone without checking the weather forecast. If I don’t like the forecast I don’t leave the boat (again, forecast reliability may be very different in the high lattitudes).
4. The rocna is more affordable ( yes, that is a factor, even for something important as an anchor. After all, I also have to buy the anchor chain, a good epirb, a good safety harness…. Etc etc and we are in our early thirties so our budget was not that big).

My point is this: I fully agree with your decision to have the spade as the recommended primary bow anchor. But all depends, like you mentioned, on the variables – and therefore for many people a rocna may be the “Best Buy” – and still a very good “Best Buy” at that.

Funny how anchors seem to be one of those things everyone (me included) has such a strong opinion about 🙂