Getting to Know Anchor Lines
Anchor lines, chains, windlasses and gypsies? While this bit of maritime lingo may sound like an all-new crazed caper of Captain Jack Sparrow in the Pirates of the Caribbean franchise, it is anything but. Read on and we'll clear this up.
What is an anchor rode? An anchor rode is a rope attached to the anchor or in combination with anchor chain, although some anchor rodes are all chain. Which anchor rode (commonly referred to as the anchor line) you get is determined by multiple factors such as price, vessel size, type of windlass, and personal preference, to name a few.
Many of the leading rope and chain manufacturers offer guidance with readily available anchor line size charts and other important information regarding your choice. To help you with that choice, we'll take a look at three different types here.
All-Chain Anchor Lines
Many of the large vessels with windlasses have all-chain anchor lines. You don't need to worry about abrasion when using chain, which makes it excellent for anchoring in coral or rocky waters. And of course, it is quite strong.
But chain is also expensive and extremely heavy. All-chain anchor lines add hundreds of pounds to the bow, which can have a negative affect on the boat's performance. Plus, the boat must be equipped with a windlass for this type of anchor line.
All-Rope Anchor Lines
Not every boat needs chain rodes, or even combination chain and rope. There are many small boats out there equipped with only an anchor and three-strand nylon rope for ground tackle. All-rope anchor lines are inexpensive, easy to stow, and quite strong yet lightweight, making them a breeze work with.
The caveat here is that rope does not have the abrasion resistance of chain, so an all-rope anchor line should never be used to anchor in a rocky seabed, near coral, or anywhere that has a lot of wave action and surge. But away from these conditions, an all-rope anchor line on a small boat can work just fine for temprary anchorage.
Even if you choose a combination of rope-chain anchor line, the length of chain connected to the rope must be the right type, depending on your needs and whether you'll be using a windlass. Once you know which chain you need and what length, you can easily keep track of how much chain you're using with chain markers.
- BBB - A.K.A. "Triple B" is Grade 30 made from low-carbon steel. Works well on gypsies due to uniform, pitch short links.
- High-Test - Grade 43, although usually called HT or G4. Many boaters prefer G4 because its high-carbon steel gives it twice the working load of BBB, so a smaller size can be used for the same strength. This makes it great for windlass use.
- Transport Chain - Grade 70, often called G7, this chain is far stronger than High Test G4 with remarkably high strength-to-weight ratio and hardness. This hardness makes it wear-resistant, although there are not many windlasses that it is compatible with.
The anchor chain must always match the windlass gypsy and the windlass manufacturer's information on the type of chain required. An ill-fitting chain is not only frustrating but dangerous, and should never be used.
Rope-Chain Anchor Lines
When all-rope just won't cut it and all-chain is too much, a good way to reduce weight in the chain locker is to use 60'–100' of G43 chain spliced to about 250' of 3-strand nylon line. This rode gives you enough chain to avoid seabed abrasion, is surprisingly strong, and can weigh in at well under 100 pounds.
Reducing anchor line weight also removes the strain on the bow roller, especially when anchoring in deeper water. This method is also more economical than all-chain rodes. And of course, your boat will perform better.
To some, the best anchor line for a boat anchor rope is the three-strand nylon rope that is used on windlasses with a specially designed gypsy that can accept chain and rope. The gypsy is the wheel or capstan on the windlass that brings your anchor line up and down. The best gypsies are the ones that accept more than one width of rope in three, eight, or twelve strands.
Other boaters with dual-purpose gypsies prefer a braided boat anchor line because it is a bit more flexible than the three-strand and is thus easier to feed through a deck pipe for stowage. Boaters without these deck pipes often prefer three-strand rope as it is more flexible and comes with a smaller price tag. Whatever rope you use, make sure it is always nylon because nyon rope is light and elastic, yet strong and easy to work with.
But even this chain-rope combination has its drawbacks, one of which is that rope can still chafe even if the chain cannot. And the weight of the chain does little to keep the pull on the anchor horizontal as it should be.
One way to solve this is to allow for a lot of extra scope to help keep the pull against the anchor horizontal. Scope is the ratio of the length of payed out rode to the vertical measurement of the bow chock above the seabed. The more scope, the better it will hold.
For most boaters, the maximum practical ratio is 10:1 and has 100% holding power. Measure the boat's freeboard at the bow and add that number to the water's depth. Then divide that sum by ten.
An easy way to know how much rode you're deploying is to mark your rope in 30' increments before ever putting it in the water. You can do this with a felt pen, but a better way is to purchase short, special rope marker tape that is pushed through the strands. You can get these tapes pre-marked in 30' increments.
Another con (if using a windlass) when it comes to the chain-rope combination is the shackle and a galvanized thimble used to connect the rope and chain. Shackles have been known to loose their pins and so must be wired with Monel or stainless steel wire, and the thimble won't pass easily through the gypsy. These pieces add bulk and cannot be used with a windlass.
Any Way You Splice It
As mentioned above, splicing is an excellent answer to the chain-rope anchor line / gypsy dilemma. Splicing three-strand anchor line to chain is accomplished in several ways and when done correctly will make a clean transition, allowing the splice to pass through the gypsy unhindered.
Splicing a braided line to a chain is done with an unprotected eye or with the use of a thimble. The unprotected eye splice will usually pass through a gypsy whereas a thimble can cause problems. However, unless you're quite good at splicing, you might not want to try this one at home, as splicing braided rope is much more difficult than splicing three-strand.
But you don't have to do it yourself. Many marine stores will do a splice for you for a small charge. Or, you could purchase a pre-spliced rope and chain package. if using a windlass, just make sure that whatever anchor rode you go with is compatible with your windlass and gypsy.
If you're not using a windlass, then eye splices will work. It's best to have an eye splice with a thimble such as a Sea-Dog. It will protect the rope from chafing, retain much of its strength rating, and retain the rode’s integrity by preventing a sharp kink. Some kits even come with a thimble already set in the eye splice.
So Many Anchor Options
The correct size and type of anchor matched with the correct chain is a prelude to capable and trustworthy ground tackle. There is a huge variety of anchors available and the size and type of anchor you need will depend on many different things. Let's first take a look at some of the different types of anchors.
- Lightweight Anchors - Often referred to as Danforth anchors. Two long, pivoting flukes resist the clogging that can come from mud and grass and when dropped, digs the anchor in up to the anchor line. Popular on small boats due to their holding power and light weight. They work best in hard sand and mud. Not good in soft mud, grassy, or rocky bottoms.
- Mushroom Anchors - They really do look like mushrooms. Best for soft bottoms like those in a slow-flowing rivers or some lakes, as they can sink into the mud and create a good suction. Not good for larger pleasure boats but fine for small craft like skiffs and canoes. There are also three-fluke mushroom anchors available specifically for rivers.
- Richter Anchor - Speaking of rivers, there is another anchor that sort of resembles the fluked mushroom anchor, but with four narrow flukes, and is designed for small craft. Popular with Tournament fishers, the Richter is said to need less anchor line, perform well in rocks, weeds, sand, and mud and will set and hold even with a scope as low as 3:1.
- Plow Anchors - Also called Delta anchors, the plow style is popular among cruisers due to its holding power in a wide variety of seabeds. The shank is either a pivoting CQR type or fixed, which is the Delta type. They perform well in sand, weeds, sea grass, and rocky bottoms. Not good where the seabed is soft.
- Claw Anchors - Sometimes called "Bruce" anchors, the claw anchor works much like the plow, but its curved flukes help it right itself no matter how it lands, or how much the boat swings. The claw allows for 360 degree turns, and these anchors are lighter than their plow cousins.
This is but a small example of the many types of anchors out there, as an exhaustive list would make for an exeedingly long article. But take a good look around at these and others, and you'll begin to get a good idea of what's out there in the world of anchors. Charts are available from the manufacturers that offer guidance in sizes and recommended function.
What type and size of anchor you choose will depend on many factors such as the weight, design, and size of your boat as well as the underwater geography where you'll be anchoring. Another consideration is the local conditions. There's a world of difference between a calm, protected cove or a lazy river, and offshore or on a large bay.
If there's room on your boat, it would be wise to have two types of anchors for different underwater terrain. Make sure you keep up on the local weather reports and pay close attention to tides, wave action, and wind. Stormy weather makes anchoring an arduous task, if not downright impossible.
Mooring Your Boat
An alternative to anchoring is setting a mooring. A mooring consists of a ground anchor or weight that has a rope or chain attached to it with the other end tied to a floating buoy. There are rules and mooring designs that are required by the controlling authority that has jurisdiction where the mooring is located, and it is prudent to get all the facts prior to proceeding with the installation.
Ironically, the mushroom anchors discussed above, which are mostly used only for very small crafts like skiffs and canoes, are quite often used for mooring. However, mooring mushrooms can weigh several thousand pounds, which makes them sink deep into a soft seabed, creating an extremely strong suction.
Of course, something must hold the anchor rode at the surface, which is where mooring buoys come in. They usually come in several colors, such as the popular Jim Buoy, and others, like the Taylor Made Sur Moor buoy, can be painted any color you like. Most mooring buoys are round but some are cylindrical or even bell-shaped.
Shackles are a convenient and efficient method of holding all the important components of a mooring rode together. Shackles must be rated to match the load and are available in stainless, galvanized, or painted steel. Swivels are also used and help prevent the twisting in the anchor chain and rode that develops over time from swinging at anchor or a mooring.
Other anchoring and mooring hardware items you may need could include a mooring snubber, like this one from Taylor Made to prevent line breakage from sudden jolting and excess stretching. And that Taylor Made Sur Moor buoy we were talking about earlier? They make a convenient hardware kit expecially for that buoy that includes the rod, swivel, washers, and lock nuts.
You will find plenty of mooring buoys, line, and hardware from manufacturers such as Taylor Made, JimBuoy, Kong, Imtra, and Sea-Dog.
Whether you're just starting out and need all-new ground tackle or simply need to replace anchor line, anchor chain, or hardware for your anchor rode, at Go2marine we're here to help.