Choosing the right anchor chain is one of the most important steps you can take to ensure your boat stays securely anchored, giving you peace of mind during every night on the water. If you're looking to replace an older, worn-out chain or upgrade for added safety, understanding the options can be confusing at first.
While living aboard our Leopard 45 catamaran we've tried both galvanized and stainless chains, so in this guide I'll walk you through some of the things to consider, from materials and grades to sizing and length, so you can make a confident choice for your next chain.
CONTENTS:
Understanding anchor chain materials
One of the first things to consider is the material your anchor chain is made of, as this will directly impact its durability, weight, and corrosion resistance. We've done a complete article on the topic, but here's a quick insight.
Galvanized steel
Galvanized steel chains are the most popular choice among cruisers and liveaboards because they’re robust, affordable, and resistant to rust, thanks to the protective zinc coating. Galvanized chains generally perform well in a variety of climates and water types, and they have a decent lifespan if maintained properly, but do degrade over time and the zinc leaching into the water may put off those who are environmentally conscious.
Stainless steel
Stainless steel chains boast long-lasting resistance to corrosion, especially if they're Duplex 318 LN, remaining relatively rust free even in challenging marine environments. The downside is that stainless chains are more expensive and can be susceptible to crevice corrosion, although electropolishing can help mitigate this problem. They can also be severely damaged quite quickly by stray DC current in the water so it's a good idea to make sure your windlass can be isolated and you're aware of the potential for it in marina's and near docks.
Personally we changed from our original chain to a Chromox stainless steel chain, guided largely by our remote area cruising plans and intention to live on the boat for a number of years.
Is stainless steel or galvanized chain stronger?
There are some arguments that stainless steel chain is inherently more brittle or weaker than galvanized steel chain. The thing to remember is that both have different alloys, finishes, grades and strength ratings, so there is more to it than simply which metal is used. It's best to look at the specifications of the chains you're considering and compare them, rather than make assumptions.
Anchor chain grades and strength rating
The grade of your anchor chain refers to its strength and durability under load, which is based off the linear strength and break load. Different grades are suited to different types of boats and conditions so understanding these grades is key to selecting a safe and durable chain.
Common chain grades
While there are a number of different chain grades, here's a look at some of the common anchor chain grades used in the marine industry.
Names | Description |
Grade 30, G30, G3, Proof Coil | A low strength but affordable choice, the working load limit of G30 is around 1300-6900 lbs (569-3130 kg) |
Grade 40, G40, G4 Grade 43, G43, High Test | G40 and G43 have the same strength levels, but G43 has lightly larger chain links. The working load limit can be between 2600-13000 lbs (1180-5900kg) |
Grade 70, G70, G7, Transport Chain | One of the strongest options used for sailboats, G70 has a working load limit of around 3150-15800 lbs (1430-7170 kg) |
Many marine stores favor stocking G40, G43 and G70 chains over the G30 as these are the stronger options suited to a wider variety of sailboats.
When looking at the various options make sure you check the working and break strengths of each chain you're considering as they are not all equal. For example, here's three comparable Grade 43 chains currently being sold by major chandlers.
Chain | Working Load Limit | Break Strength |
Titan Grade 43 | 2425 lbs (1100kg) | 9700 lbs (4400kg) |
ACCO Grade 43 | 3900 lbs (1770kg) | 11600 lbs (5260kg) |
Trident 43 | 2200 lbs (1000kg) | Not listed |
Matching the grade to your sailing and boat
When choosing which grade to get here's some things to consider.
Boat size and windage
Typical anchoring environments including salinity and depth
Frequency of use
What was previously installed
For our 45ft Leopard Catamaran we currently have a Grade 60 PLUS chain. It's stainless steel but the break test load is around 10200 kg (22500 lbs)
Choosing the right anchor chain length and size
The length and diameter of your anchor chain are also crucial factors. Generally, the bigger and heavier your boat, the thicker and longer the chain should be.
Determining chain length
The right chain length depends on your boat size, expected anchoring depths, the weather conditions and intended cruising grounds. Ideally you don't want the angle of the chain from the anchor to the boat to exceed 8 degrees to ensure a firm holding, and keep in mind the weight of the chain also helps hold the boat.
Many liveaboard cruisers carry around 250-350 feet (75-110m) to allow for around a 5:1 anchor scope in normal conditions, and 7:1 and above in rough conditions. There is also the possibility to extend the chain with rope if needed.
Choosing chain diameter
The diameter of your chain impacts the strength and weight. A heavier chain may hold more securely, but it also adds weight to the bow which can affect your boat’s handling.
Checking with your windlass manufacturer for the compatible chain size is essential, as windlasses are often designed to work with specific chain diameters. Common diameters range from 8mm to 12mm for cruising boats, with thicker chains providing extra weight for holding in challenging conditions.
What are DIN and ISO chains
DIN and ISO are European chain manufacturing standards that determine the dimensions of the chain links. DIN 766 is the German industry standard while ISO 4565 is used by most other European countries. Sizes for these chains are generally metric.
Australia is also metric, generally based off the AS2321 standard.
American made chains are usually in inches, complying with ANSI standards.
Anchor chain brands
When buying an anchor chain it's always advisable to choose a known brand with a good reputation over a cheaper no-name chain. Here are some to get you started.
Tips for choosing and using anchor chains
Here are a few additional tips to make the most of your anchor chain.
Experiment with different lengths and settings to see what holds best in various conditions. This could include trying different anchor swivels, like the popular Mantus swivel.
Having a chain counter installed or marking the chain at regular intervals can help you gauge how much chain you’ve deployed, especially at night or in low visibility. If you want to mark the chain you could spray paint it or use plastic anchor chain markers.
Chains can be heavy, so make sure to give your windlass a break if hauling in large amounts. This can prevent overheating and reduce wear on the windlass motor.
Be aware of the potential for galvanic corrosion in your anchoring setup if using dissimilar metals.
Summing it up
Choosing a high quality anchor chain is one of the best steps you can take to ensure your boat remains secure, whether you’re anchored in a calm bay or a windy cove. By considering the right materials, grade and length, you’ll be well-prepared to make an informed decision that matches your boating needs,
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