Old generation anchors
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The topic of this section is supplemented by an article at the Rocna designer's personal website.
To read this article, click here: Old Generation Anchors |
Old generation anchors include most types and designs dating before the Bügel (1986) and Delta (1990). Because the Bügel uses what we consider to be some new generation design characteristics whereas the Delta is first and foremost a plow, these two types define a bit of an overlap between the 'old' and 'new' generations which marks the transition from old to new on the timeline.
The most obvious old generation types are those which we would not call "modern" anchors, with their origins well before the 20th century, and typically are recognized as not being small boat anchors. The old Fishermans style and Admiralty patterns have a fascinating history all of their own, and occupy a unique place in the nautical annuls of the world. However, they are now mostly relegated to that history and have little or no place onboard a modern small boat. (By "small boat", we mean anything using an anchor much under 200-300 kg. Vessels above this size begin to require certain characteristics of their anchors, such as a symmetrical nature, and are outside the scope of this article).
CQR (plow)
| “ |
I've used most types of anchor - CQR, Bruce, Danforth, Fisherman etc... I was most frustrated with the CQR, even though ours was oversize for the boat. In the hard, fine sand of the Isles of Scilly I came the closest I have ever come to losing a boat, when our CQR dragged in 60 knot gusts. Many, many times I cursed the thing when trying to get it to bite in any anchorage where there was weed present. So when the new generation of anchors came along I was ready to give one a try, and plumped for the Rocna... and I have to say it has proved (over the last two seasons) worth every penny. Not only does it set instantly like a car's handbrake and hold like a rock, but, remarkably it does so in such a wide variety of substrates. It really is the best piece of kit I've bought in recent years. British yachties are very conservative - most of them will not hear a word against the good old CQR. But... most people who sail "outside the box" a little wouldn't have a CQR as a main anchor these days, any more than they would want to fly across the Atlantic in a biplane. I am convinced of one thing - anyone who ever tries one of the new generation of anchors will not be going back to their old CQR in a hurry. |
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| — Colin Speedie, writing on Attainable Adventure Cruising | ||
History and current status
The CQR was developed in the early 1930's by British mathematician Geoffrey Ingram Taylor. The CQR is an articulating plow, as opposed to the improved fixed shank variant of the plow concept (i.e. the Delta) of decades later. The articulation was necessary for the anchor to set, by angling the fluke tip to the seabed correctly. This worked only partially and the hinge was a headache, creating wear issues and injuring many a boater's finger(s) – a problem not solved until the Delta.
The genuine CQR brand is now owned by Lewmar, having been traded a number of times in its lifetime. Naturally the anchor is out of patent and poor copies abound, most of even worse performance and questionable construction quality. Unfortunately their popularity is assisted by the relatively high cost of the genuine CQR.
The relative performance of plows
The CQR was inarguably a massive improvement over the antiquated alternatives available in the early 20th century, and was the world's first "small boat anchor". In the 50 years following its launch, it enjoyed a near monopoly on the small boat market, while this market remained fairly small and exclusive. This established it with a strong legacy and a status in the minds of many boaters as the anchor of choice. Tradition and lore, especially in the nautical world, are powerful endorsers. However, there has been much work and development on anchors since, and the performance of plows compared to the all-round excellence of new generation types is really quite miserable – much like many other products from the 1930s compared to their modern replacements!
Performance problems with the CQR are evident across all measures which would define a good all-round anchor, including inconsistent setting performance (often not setting at all), poor holding in soft bottoms, and failure to penetrate in hard. The fluke shape, unsurprisingly perhaps as it is a plow, is inherently designed to furrow, not hold, and this shape being used for the CQR was a necessity at the time as it was not clear how to make a different shape set reliably. It does not handle weed or grass at all well, and generally has few redeeming features.
Inconsistent setting leads to unpredictable anchoring. Anchors must be in a particular attitude in order to set, and slight flaws in the design of the anchor lead to the attainment of this attitude being a hit-and-miss affair. If an articulating plow lands with its blade in an upright position, it will usually set without problems, but if the fluke (the actual plow part) lands on its side, with the shank rotated away, it may well not set at all. Especially on a hard bottom, it is not uncommon to drag a plow in this situation for 50 meters without a set. Moreover, this has obvious implications for an unattended boat which pulls out its anchor (perhaps during a wind veer) and must rely upon it automatically re-setting.
The CQR was tested and developed primarily in the forgiving English anchoring grounds of Essex and Suffolk, which present an environment of almost entirely soft mud and sand. Cruisers these days tend to demand an anchor capable of handling more exotic environments. It is perhaps a result of this that the plow is not to be recommended as a general purpose anchor and has no place on a modern yacht.
Compared to the Rocna
There is a large amount of independent testing of both the CQR and Rocna. However, the following summary comments from West Marine in the USA relating to their 2006 comparison testing best sums up the true differences.
| West Marine 2006 testing Quotes complete |
CQR 35 (38.5 lb): | |||
| “ | One promising set to 2,000lb., but little else. Would not engage bottom. | ” | ||
| Rocna 15 (32 lb): | ||||
| “ | Superb, consistent performance. Held a minimum of 4,500lb and engaged immediately. | ” | ||
The CQR, and many articulated plough copies, are HHP (High Holding Power) classified by one or other of the classification societies (Lloyd's, RINA, et al). The Rocna however has SHHP (Super HHP) classification. The SHHP standard requires the anchor to resist pulls at least 200% that of a HHP anchor, over three different seabeds.
More resources
- Original CQR patent
- Photo journal of testing comparing genuine CQR to a knock-off (and both against a Rocna)
Danforth type
History and current status
The Danforth is a twin-fluke symmetrical anchor, which means it has strong connections with most anchors of antiquity including stockless types. The flukes can "flop" either side of the shank and the anchor works regardless of which side lies on the seabed. It was developed a little after the CQR by American Richard Danforth, comprising the United States' sole significant contribution to modern anchoring so far in history! A number of patents were filed for various iterations of the design, but the recognizable current form was filed with the US Patent Office in 1948.
Genuine Danforth anchors are now produced by Tie Down Engineering of Atlanta, Georgia. The name, while trademarked, is fairly genericized and many imitations are incorrectly referred to and even sold as Danforths.
The relative performance of Danforth types
The Danforth type's primary distinguishing feature is found in its large flat plate flukes, which offer a large surface area for the weight of the anchor. When set, this translates to a high holding power, well in excess of the CQR, its only small boat competitor at the time of its development. The Danforth still offers good performance by this simple measure – its problems lie elsewhere.
The Danforth is in essence an improved version of the 19th century Admiralty pattern and stockless variations thereupon. It offers better holding power, and attempts to dampen the rotating impulse (which results from the presence of more than one fluke) with several tricks including its stock (located in front of the flukes rather than at the end of the shank). However, it still suffers from a number of setting and behavioral problems. Because the flukes lie flat on the seabed before it is set, the setting process depends on the tip of a fluke getting an initial 'bite' – and on hard sand or grassy seabeds, this is more easily said that done. It can skate along the surface without setting at all. This initial setting issue then implies other problems later.
| “ | The closest I've come to disaster was when my anchor dragged over a mile across a bay, towards rocks and a wall of concrete at Seaview, Isle of Wight. It was 0300 and everyone aboard was asleep when a windshift, aided and abetted by a change of tide, caused the Fortress FX-16 anchor to break out and drag... Though renowned for superb holding power, Danforth types can break out if the pull changes direction and they don't always regain their grip... | ” |
| — Editor's Log, Yachting Monthly December 2006 | ||
Its behavioral problems include an inability to handle force veers. Rather than remain buried when a sideways or reversed pull is applied, it tends to rotate and pull out. Similarly, if the anchor is dragged once set (e.g. in soft mud), it has a strong tendency to twist and rotate, again popping out. Once this has happened, the anchor is unlikely to re-set itself.
There are a number of other issues, including a reduced strength and durability. Even with good quality construction and high tensile steels, the geometry of the design does not lend itself to a rugged build. The flukes are just flat plates with little reinforcement possible, and the tips are easily damaged. Furthermore, if the force on the anchor is unbalanced, e.g. if one fluke gets stuck but not the other, it is very easily bent and destroyed.
Because the Danforth type is flat, it tends to be easily stowed, and is therefore a popular secondary anchor. Additionally, it does hold fairly well in simple circumstances, and so is a reasonable solution for a second anchor (where force veers are minimal, and the anchor may be set once and not expected to handle more than a unidirectional pull). Nonetheless, there are other modern solutions which are superior for this purpose, including the Spade which has a demountable shank and is available in lightweight aluminium, and also of course the Rocna Stowable.
Compared to the Rocna
There is a large amount of independent testing of both Danforth types and the Rocna. However, the following summary comments from West Marine in the USA relating to their 2006 comparison testing best sums up the true differences. This Danforth type is the "West Marine Performance" version.
| West Marine 2006 testing Quotes complete |
West Marine Performance 20 (26.3 lb): | |||
| “ | Disappointing results considering previous tests. Held 200 to 1,500lb, but could not get a secure grip. | ” | ||
| Rocna 15 (32 lb): | ||||
| “ | Superb, consistent performance. Held a minimum of 4,500lb and engaged immediately. | ” | ||
More resources
Bruce (claw)
History and current status
Peter Bruce launched his new anchor to great interest from the boating community in the early 1970s, the UK patent having been filed in 1971. The anchor features a triple fluke configuration which forms a 'claw' shape. It enjoyed a good level of success, addressing many of the problems, mostly those pertaining to setting reliability, of the CQR and Danforth, then the only current alternatives. This success was perhaps its downfall when the intellectual property protection expired, as it quickly became one of the most imitated types. The design is best cast rather than fabricated, lending it to very cheap production processes which take shortcuts on the heat treated method used originally by Bruce Anchor Co in the Isle of Man. The genuine Bruce is no longer produced, and today only the inferior quality copies remain available.
The relative performance of claws
Claw types, despite the initial success of the original Bruce, do not perform particularly well in terms of holding power. They are therefore inefficient, requiring a heavier anchor to achieve the same holding ability as even a plow.
| “ |
Much of their popularity derives from the ease with which they stow on the stemhead. But their performance proved disappointing... In gravel these claws bounce about whereas in sand they lie down on their side and rarely exceed 200 kgf of holding power. |
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| — Antoine Sézérat, Voiles et Voiliers | ||
The anchor's benefits instead supposedly lie in setting performance, and compared to plows and Danforth-types, it is true that claws generally perform better across a somewhat wider range of seabeds. However, this comparison is not particularly useful in light of the new generation of anchors now available, and the claw does have a number of serious flaws. One of these was described by a magazine tester as "hop and skip" behavior, which refers essentially to the fact that the claw is inherently unstable when pulled beyond yield (dragged). It tends to rotate then pop out violently.
The claw also has three separate flukes, all fairly blunt, which do not cut and penetrate weed or grass very well. This also affects its setting performance in hard sand and clay. The shape of the flukes also tend to act as a trap for rocks and boulders, and other undersea obstacles, giving the design a poor reputation for getting itself fouled on these things.
Moreover, the claw does not set particularly well in harder seabeds if the anchor lands upside-down. In this position it relies upon one of the side flukes 'grabbing' the ground in order to trip the anchor into the correct attitude. Unfortunately the anchor is quite capable of remaining on its back and skating along indefinitely.
While the claw was the anchor of choice for many well known sailors and cruisers for many years, the death of the genuine Bruce combined with the progression of technology has seen many of these boaters adopt new generation anchors instead. Cruising guru couples Steve & Linda Dashew (SetSail) and Evans Starzinger & Beth Leonard used to have Bruces on their bows, and are now using Rocnas.
Compared to the Rocna
There is a large amount of independent testing of both the claw and Rocna. However, the following summary comments from West Marine in the USA relating to their 2006 comparison testing best sums up the true differences.
| West Marine 2006 testing Quotes complete |
Claw 33 (36.3 lb): | |||
| “ | Failed to set during this test. Maximum tension under 700lb., briefly. | ” | ||
| Rocna 15 (32 lb): | ||||
| “ | Superb, consistent performance. Held a minimum of 4,500lb and engaged immediately. | ” | ||
Some claws are HHP (High Holding Power) classified by one or other of the classification societies (Lloyd's, RINA, et al). The Rocna however has SHHP (Super HHP) classification. The SHHP standard requires the anchor to resist pulls at least 200% that of a HHP anchor, over three different seabeds.
More resources
Delta (fixed shank plow)
The Delta is a fixed shank plow, essentially a development of the CQR as described above. By this definition it is an old generation anchor, but it nonetheless has its own page: Delta anchor.