This is another great Google Map from Louise Busby..and in her own words “An increasing number of superyacht owners and charter operators are relocating their vessels to far-flung corners of the globe to entice the growing band of charter guests tired of cruising round the same old watering holes. We’ve searched the planet for the pick of these yachts and the experiences they offer, from sun bathing with iguanas in the Galapagos to snorkelling with elephants off those gems of the Indian Ocean. “….Great job Louise !
Rocna Anchors has released a comprehensive online collection of information on the topic of anchors, anchoring accessories, and the science of anchoring.
The Rocna Knowledge Base is a comprehensive, indexed and searchable digital encyclopedia covering anchors and anchoring.
The new website includes a section specific to anchors, including a collection of Rocna installation case studies, and guidelines for designing and building the ideal bow roller. Analyses of independent testing, explanations of anchor classification/certification, advice on sizing anchors and much more is also available online.
Content is not restricted to anchors; major sections focus on the rest of the anchoring system – chain, rope, connectors (shackles and swivels), windlasses, etc. Optimising rode make-up, best practice anchoring techniques, multiple anchor rigs, tandem anchoring and optimising the scope and catenary of the rode for best anchor performance are just a few of the topics covered in-depth.
Mobiletide is a Java program designed to run on your phone without need to connect to the phone network (GSM) or the internet (GPRS) – just as well !
It has a database of worldwide locations and can display a tidal curve for any location without you having to reference tide tables or do any standard port calculations.
The makers list a broad range of mobile phones that are supported, but basically any phone that runs a Symbian or Windows Mobile should suffice since they will then support internet connections and also Java software.
Mobiletide is synchronised to the moon’s daily cycle of 24hrs 50mins and 28 seconds. On average across a Lunar day (month) this is how much the tide moves on by each day. Working to an average tidal progression means that Mobiletide will remain accurate over a longer period of time, so in 5 days, 5 months or 5 years mobiletide will still be showing the correct tide. It does mean that throughout a month Mobiletide will fluctuate in and out slightly, however it will remain within 0-30mins for the majority of the time.
There are other influences on sea levels that affect exact tide times and these should be taken into account e.g. Strong on / off shore winds; Changing volume of river flows; Atmospheric pressure
Due to the variable nature of tides mobiletide is only intended as a guide to tide times. If you do have internet connection however, then the makers claim that Mobiletide has direct links to the most respected swell, wind and weather WAP sites around the world, providing the whole detailed picture.
I was also considering installing a windlass but I knew that that was the type of job that could lead from one problem to the next and so I was more cautious about that final step.
The anchor locker lid would need strengthening, or modifications made to the area of the deck where the roller reefing mechanism attaches – all sounds too elaborate – first rule of DIY applies – KISS !
According to Lewmar the calculations of weight of anchor, rhode and corresponding windlass look something like this:
All looks pretty straightforward – apart from the installation, I decided it wasnt worth the hassle, and my 1st mate (wife) can continue to haul the anchor….well someone has to do it !
When I bought Enterprise she came with a 22lb Danforth type anchor that is stowed in the anchor locker. Although this is neat and tidy in most circumstances it is quite tricky to lift it out of the locker on a pitching foredeck, without drawing blood . Because it is hinged and the flukes are so large it is impossible to stow it on the bow roller without it taking a chunk out of the hull. Hence, the search for something more suitable.
After much searching of the web and various blog opinions I felt that the choice for my 32ft boat would lie between the old favourite the CQR and the newer Delta – both from Lewmar. Although the Rocna anchor and web site is very impressive.
Clyde Quick Release Plough (CQR)
So named due to its resemblance to a traditional agricultural plough (or more specifically two ploughshares), many manufacturers produce a plough-style design, all based on or direct copies of the original CQR (Secure), a 1933 design by mathematician Geoffrey Ingram Taylor.
Owing to a now well established history, ploughs are particularly popular with cruising sailors and other private boaters. They are generally good in all bottoms, but not exceptional in any. The CQR design has a hinged shank, allowing the anchor to turn with direction changes rather than breaking out, and also arranged to force the point of the plough into the bottom if the anchor lands on its side.
Another more recent commercial design, the Delta uses an unhinged shank and a plough with specific angles to develop slightly superior performance. Both can be stored in most regular anchor roller systems.
Owing to the use of lead or other dedicated tip-weight, the plough is heavier than average for the amount of resistance developed, and may take a slightly longer pull to set thoroughly.
The genuine CQR and Delta brands are now owned by Lewmar, although they have both been on-sold several times during their lifetimes.
The Delta was developed in the 1980's for commercialisation by British marine manufacturer Simpson-Lawrence. The Delta is a fixed shank plow, as opposed to the articulating variant of the plow concept (i.e. the CQR) of decades earlier. The need for articulation was avoided with more careful balancing of the anchor's weight and shaping of the rear end of the fluke in order to better guide the fluke through the setting process. The basic shape nonetheless remains a plow, with a brake-pressed plate heel and solid steel cast tip (welded together to form the only joint attaching the tip to the rest of the anchor) which comprises the fluke. Like other plows, this design relies on tip-weight for ballast and setting, an inefficiency which detracts from fluke surface area and ultimate holding power.
The genuine Delta brand is now owned by Lewmar. The anchor has been out of patent for a few years now, and poor copies abound, most of worse performance and questionable construction quality.
The Delta utilizes a high tensile steel shank, an element which is typically the first to be sacrificed in the pursuit of cost savings by knock-off producers.
From all the reading I think the Rocna is probably the best. The New Zealand designed Rocna has been produced since 2004. It too features a sharp toe like the Bügel for penetrating weed and grass, sets quickly, and has a particularly large fluke area. Its roll-bar is also similar to that of the Bügel. The Rocna obtained the highest averaged holding power in SAIL magazine's comparison testing in 2006.
In the end I chose the Delta from Lewmar. If I had a bigger boat say 40ft upwards, I would have chosen the Rocna.
It is actually quite large and difficult to mount permanently on the bow roller since it is rigid unlike the CQR which has a hinged head. Also if you drill the anchor in order to fasten it to the bow roller you invalidate the 5 year guarantee. Anyway it does look the business and all the technical assessments appear positive – and its is from Lewmar – who should know about these things :-).
Now all that remain is to try it out – which I plan to do when we sail to Alderney on Sept 14th.
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