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ANCHORS
& ANCHORING
pt 2
Anchors and Ground Tackle
Part 1 of Anchors & Anchoring looked at
all the various anchor types anchor makers and how to choose the anchor which is best
suited for you and your boat or vessel.
Part 2 looks at the rest of the ground tackle the Anchoring Gear, & Anchor
Equipment that attaches your
boat to the anchor.
Article overview and quick links
This article is divided into 2 parts;
A
Ground
tackle the parts.
B
Factors
involve in setting your Anchor and ground tackle
Other information; Sources of anchoring techniques,
Conclusion, Reading
Part A
Ground
Tackle Parts
Ground tackle refers to all the parts of an anchor package between the
boat and includes the anchor. If you use only line the ground tackle may be
referred to as simply the anchor line.
Parts of an anchors "ground tackle"
| Anchor |
See
part 1 which will help you decide the best anchor type
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| Chain |
Chain is use for chafe protection and
weight to keep the angle between anchor and rode low
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| Rhode |
Nylon is best because of stretch characteristics
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| Splice |
Chain Rope Splice instructions for those who want to make their
own
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| Shackles |
oversize and secure them with wire or wire
ties
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| Swivel |
A swivel is used between the Anchor and
chain to let the anchor settle
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| Snubber |
A snubber is a means of dampening the
jerkiness of riding at anchor
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| Kellet |
This device is a weight that
slides down the anchor line which helps increase scope. |
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Secure Ground
Tackle to boat |
How many times have you heard that someone
threw their anchor overboard because the line did not tie, the
anchor to your boat. Make sure the connection is accessible
in case you need to ditch the anchor. Have a pad eye to tie the anchor line to the boat,
or have an
eye splice |
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| Retriever |
When the Anchor gets jammed in a rock or
refuses to break free a boat anchor retrieving device or system is needed.
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Roll Stabilizer |
At anchor boats roll. Roll stabilizers can
be mechanical or passive |
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all chain Ground Tackle
All chain is popular on large boats, heavy displacement boats, large
power boats and Mega Yachts. The two benefits of chain are weight and
chafe. Weight keeps the chain on the seabed which keeps the angle of the
anchors shank close to parallel with the bottom.
If this angle gets too
great then the anchor can break free. With the chain on the seabed, it is
subject to chafe, and chain can withstand chafe much more than rode, rope
or warp.
The
down side to all chain is again weight, and also the lack of stretch. Chain is heavy
and 200m of 10mm diameter chain is going to weight 560 kg, which means
20M will weigh 56kg. Stowing this up forward in a boats vastly increases
the chance of pitching in waves. The chain also takes up more space.
The second issue with all chain is lack of stretch. This manifest itself
in 2 ways. First in a swell and wind the boat is moving around over the
anchor. As the boat gets further away, the ground tackle will load up
and pull the boat back to the middle. This loading up will transfer to
the boat and the crew will feel the jarring. Crew may even fall down
because of this shock loading. Here it is necessary to have
an anchor snubber to dampen the load.
The second result from lack of stretch with all chain is again anchoring in a swell.
Here the
load from the vessel is transferred through the chain and the forces
transferred to the anchor, possibly braking it free. Again using a snubber with
dampen the load.
Chain comes in 3 types. To learn about these types of chain follow
this link
all rode Ground Tackle
For smaller boats having an all rope, anchor line, warp or rode is more popular. It is lighter,
can be thrown, takes up less space and stretches. The down side is
chafe.
Unlike chain rope stretches and this results in a smoother ride at anchor.
When the boat swings at anchor and loads up the line, the load is
disipated by the stretch in the line. Unlike with Chain the load is not
transferred to the anchor, and so the anchor is not effected.
Twisted three-strand
nylon rode, has good stretch properties, it also sinks. For the rode a
nylon line is very strong and with the 3 strand construction has lots of
stretch
Polypropylene has good stretch floats but has poor shelf
life in the sun.
Three-strand line can absorb shock and the constant tugging associated with
anchoring much better than braided line.
Nylon
Three-Strand line is the leading choice for use as an anchoring line. Lines
generally come in a "soft" or "medium" lie. Soft lines are generally softer and loosely woven,
than medium or hard
lines for anchoring, as they are more prone to unraveling and chafing.
Medium and hard lines are best to handle chafe. Lines
that have been treated with a wax-like coating are available, and can
help the line resist water/salt absorption.
Chain Rode combinations
Since all chain or all rode have their pros and cons a combination chain
and rode is most popular. Here the chains weight and chafe
characteristics prove their worth on the seabed. The rode proves its
woth with the stretch, so dampening any shock loads from the boat
swinging around. Also the rode takes up less space.
So how much chain should we use. In the next section we look at how much
anchor rode ground tackle you will need. This is calculated on scope.
Scope is the ratio of water depth to line put out. This ratio is
somewhere between 3:1 and in extreme cases 10:1.
How much chain to rope

some rules of thumb say one ft of chain per foot of boat length. Another
says one lb of chain for every pound of anchor.
Chain to Rode length calculation
Earl Hinz, a
former aeronautical engineer and inveterate Pacific Ocean sailor, in his
work The Complete
Book of Anchoring and Mooring, says the chain lead should weigh at
least as much as the anchor whose weight it is supplementing.
From his
experience, he has determined that the length of the chain lead has nothing
to do with the depth of the water or the length of the boat. He suggests
using the following formula to help you determine the minimum
length of chain lead you will need:
Minimum
Anchor weight in lbs.
length of = x Anchor
materials factor
chain lead Unit weight of
chain,
lbs./ft.
Anchor materials factor = 1 for steel and 1.6 for aluminum
For example: If you have a 7-lb. Fortress aluminum anchor
with a 1/2 inch twisted three-strand nylon rode, you would need to use at least
11.2 lbs of 5/16 inch proof coil chain, which weighs 1.15 lbs per foot.
Therefore, you will need at least 9 ft 8 inches of boat anchor chain.
More parts of the Ground Tackle. These are some
examples of the various parts, and boat anchor accessories that go
into making the best ground tackle system.
Anchor
rode chain Splice
How to make your own
Splice by animated knots.
This splice by animated knots lets you see the
splice step by step.
You can use an eye splice and shackle but this
will not work with a chain rode Windlass.
Anchor Swivel
A swivel allows the anchor to settle on the seabed and the anchor chain or
line to align to pull horizontally.
Many swivels operate in one plane only. This swivel can articulate as well
as swivel.
Chain Snubber
A
snubber is designed to provide shock absorbing capability into the system.
Chain does not have any give and so loads give the boat and crew a jarring
feeling which can make life onboard uncomfortable
A Chain snubber is basically some
twisted three-strand
nylon attached to a hook. The line is tied on the boat and the hook
hooked to the chain.
The increase the stretch you can lead the line down the
boat and tie it off on an aft cleat. A longer line means more stretch.
The image left is of
Shockles
another type of chain snubber.

Boat Anchor retrieval system
Retrieving an boats anchor is best done by motoring up to the anchor. Do not use a
windlass to haul yourself to the anchor. Once at the Anchor pull the ground
tackle rode tight, and then move weight aft and let the boat lift the anchor.
Anchor can be hard to get to dig in, but when they do they can be hard to
get out. Retrieval systems help breaking the anchor free of the bottom.
The AnchorLift is one example of an anchor retrieval system.
Roll Stabilizers
When lying at anchor boats tend to roll. Roll stabilizers or
Rocker
Stoppers combat this.
Davis
Rocker Stoppers help dampen the rocking motion of boats at anchor. Simply tie Rocker Stoppers approximately 44 cm (18") apart, making a string of them, with a 5-10 pound weight attached at the bottom of the string.
If a rocker stopper is not enough
try a stabilizing fin which is a mechanical fin controlled by
software. Use on larger boats, the software changes the angle of the fin
to appose the roll motion. Some stabilizers for anchored boats are
called Zero speed stabilizers.
Links to anchors
and anchoring equipment
Size of the anchor ground tackle
What chain diameter do I need and what line size do I need. These
diagrams from the ABYC will help you decide.

This Chart from part 1, gives you an anchor horizontal loads at various wind
speeds.
For our 30 ft boat the horizontal load is 700 lbs for a Working Anchor which
is rated at 30 knots.
Below you will se that for this boat 7/16 inch line is recommended and
5/16 inch chain.

Chain Types
types of Boat Anchor Chain
excerpt from good old boat via
sailnet
Proof coil chain is made of low-carbon steel. It
usually will have "G3" cast into each link. Its name comes from subjecting
the chain to tensile loads (its proof load) until it breaks.. Anchor
chains working load rating is usually 50 percent of the proof load.
Proof coil is usually the least expensive chain, since it has fewer links
per foot. Proof coil will not work with a windlass.
BBB chain (known as triple-B) is also a Grade-30 low-carbon steel. It can be identified by the "3B" cast into each link.
It has been the chain of choice for boaters for years since its added weight
creates more of a catenary and its shorter links have less chance to deform.
High Test (HT)
boat chain is made from high-carbon steel that
has been heat-treated to increase its strength. The heat treating gives HT
chain a higher
strength-to-weight ratio than other chain. "G43"
or "G4" are cast into the links. With slightly longer links than BBB chain, many windlass manufacturers
specify HT chain as the most compatible with their winches.
COATINGS
All these chains are galvanized.
Some
anchor chain can be purchased with a thin polymer coating. Vinyl coatings
are also used. which makes the chain thicker, but gives more protection.
Stainless-steel
anchor chain is also available. This is 316 stainless and is stronger than the
steel, galvanized counterparts, but not as strong as high-carbon HT galvanized chain. It
is also considerably more expensive than any of the galvanized chains. It
does, however, prevent rust stains.
Links to anchors
and anchoring equipment
Part B
Factors involved
in setting an anchor and ground tackle
Scope in ground tackle.
Thanks
to
Sailnet
and good Old Boat for the image and linkAll anchors are designed to dig in when pulled horizontally. If pulled
vertically they break free, otherwise we would not get them back.
Scope is the ratio of depth to line paid out.
Short scope (3:1) limits your swing in a crowded anchor, but is harder to get a
good hold on the bottom.
Longer scope increases the holding power of the anchor, but you will need
more space and the likely hood of sailing around the anchor increases. The
above image is 5:1 scope 100 ft in 20 ft water depth.
Problems with long scope
Long scope helps getting an anchor to dig in as the anchor line is more
likely to pull horizontally. The problem with lying to a long scope is that
you need lots of space which you might not get in a crowded anchorage.
Secondly you will find out about anchor sailing. This basically means
that the wind will blow you side ways and when the anchor line goes taught
you are pulled back. The momentum built up sends the boat to the other side.
So you are essentiality sailing around the anchor which gets uncomfortable
and the anchor line goes taught slack and taught again.
So how do you prevent this. One way is the put up an anchor sail, another
is to hand a large
bucket
(
check this link) from the bow. This acts to dampen the swing as the bow
has to tug on the bucket dragging it through the water.
Bahamian anchor method is another method we will be looking at in part 3.
This involves setting two anchors.
How do you measure scope length
mark the chain
Imtra
have these markers you can press between the links at measured points like
very 10ft or 3 meters. A different color for 20ft and 30ft will let you know
how much scope you have let out.
Mark the line with magic marker or slip some leather strips in between
the strands.
Chain rode counter
Auto Anchor
Remote chain counter telling you how much chain or line you have let out. The counter will work for either chain and rope/chain Rhodes. AA150 is Freeman K. Pittman award winner 2006.
Anchor
data
This counting device can replace your anchor roller or
be placed behind it. Designed for boats in the 25-45 ft range and rope dia
8-20mm and chain 6-10mm. £250 ex vat. The LED display on top of the unit
counts the anchor rope or chain from the last reading or from zero if reset.
The LED is solar powered so does not need wiring.
How to get the features of a short scope but with a long line.
Anchor kellets, angels
sentinels
These are weights that are added to the anchor line or chain with a large
shackle or loop which allows the weight to slide along the chain. The weight
is lowered down the chain (see below). The effect is to lower the angle of
the chain at the anchor bringing it closer to horizontal.
The
anchor buddy is
a kellet (also known as chums,
angels, sentinels, anchor angels) which have been used for generations to anchor
boats more securely. They also reduce the swing radius up to 50%.

Sources
of anchoring techniques
Sailnet
"to
have and to hold" sponsored by "Good Old Boat" The
basic rules of anchoring -- and staying put. by Don Launer.
A
technical look at Ground Tackle
sailonline
the charter company's instruction on anchoring
Sailing
issues, a free and personal website providing unique information on marine
navigation and sailing holidays in Greece and
Turkey. lessons on anchoring
Links to anchors
and anchoring equipment
Conclusion
There is no perfect ground tackle and many cruisers have backups and
variations of the main system.
Setsail.com
has experts in the cruising community and they here tell you what
systems and ground tackle they use and for what conditions.
In part 3 we look at techniques of anchoring in harsh conditions.
When dropping anchor make sure the
coast is clear
Other reading
Captains
anchoring Quick Guide
What
you need to know about anchoring--fast and easy! Anchoring is a necessary
skill for any boater--power or sail--whether you are planning a picnic
lunch in a secluded cove or an overnight visit in a distant anchorage.
This 16-panel, foldout guide provides you with fast, easy-to-follow
instructions for safe and efficient anchoring. Anchoring is in full color
and is printed on hinged, heavily laminated, waterproof pages, so this
tough resource will hold its own even when you are in rough weather.
by Peter Nielsen
The
Complete Book of Anchoring and Mooring
This
book has been cited in a few sites like www.boatsafe.com
and other respected organizations.
Contents
Chapter One: Introduction
Part I: The Technology of Ground Tackle
Chapter Two: Loads at Anchor
Chapter Three: Deck Gear for Anchors
Chapter Four: Anchor Windlass
Chapter Five: Anchor Rhodes
Chapter Six: Anchor Options
Chapter Seven: Anchor and Rode Selection
Part II: The Art of Anchoring
Chapter Eight: Human Factors in Anchoring
Chapter Nine: Technique of Anchoring
Chapter Ten: Anchoring Tricks
Chapter Eleven: Rights and Responsibilities
Chapter Twelve: Storm Anchoring
Part III: The Mechanics of Mooring
Chapter Thirteen: Permanent Moorings
The
Complete anchoring handbook
A modern, authoritative anchoring guide for sailors and powerboaters A
boat swinging safely at anchor can be a relaxing conclusion to a great
day of boating or an essential emergency measure, while failure to
anchor properly can be frustrating, inconvenient, or downright
dangerous. The Complete Anchoring Handbook is your path to mastering
this indispensable seamanship skill. Based on original engineering
analysis--and with contributions from such international anchoring
experts as Alain Fraysse and Chuck Hawley--The Complete Anchoring
Handbook emphasizes the proven best gear and methods for anchoring
safely in any situation with any boat, sail or power. Here's everything
you need to know, from the basics to the most advanced techniques
US
Sailing Bareboat Cruising
One
selection form this manual covers Anchoring Techniques
24. Select an anchorage and demonstrate appropriate helmsman and crew
coordination and the skills necessary to anchor with two anchors under
power using one of the following methods: bow and stern, two anchors off
the bow at 60° , or two anchors off the bow at 180° (Bahamian Moor).
25. Pick up a mooring.
26. Demonstrate appropriate helmsman and crew coordination and the skills
necessary to recover your anchor under power.
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