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Selecting the Right Anchor Size

Holding power increases with weight, but how much is hard to calculate..

Over the years Practical Sailor has conducted dozens of anchor tests, and like many publications, we’ve repeated the common guidance that cruising sailors should buy an anchor that is at least one size larger than what the maker recommends for your size vessel.

During the last two decades, however, the tremendous holding power of some newer generation anchors have caused us to re-think this guidance. Are we paying more for an anchor, rode, and the requisite anchor handling equipment than we need? How accurate are the makers size recommendations? How much insurance are we really getting for the price of a bigger anchor?

For this report we took a range of modern, sometimes called new generation anchors, and their predecessors and averaged their weight vs. vessel size recommendations (see accompanying table). Much to our surprise, the weight recommendations for the new designs, Rocna, Excel, Supreme, etc. are very similar to the weight recommendation for the older, traditional models, CQR, Delta, Bruce etc. In both cases, the recommendation for a 35-foot yacht is approximately a 30-pound anchor. The exceptions are aluminum anchors from Fortress and Spade.

Most of the new generation anchors have been tested to international standards established by the RINA (Registro Italian Naval) or some other internationally recognized society. Rocna, Fortress, Supreme, Excel, Spade have been found to meet standards of Super High Holding Power, SHHP. The older anchors, CQR, Bruce, Delta are rated as High Holding Power. The difference between the two categories is that the SHHP have been tested and found to have a hold, comparing anchors of the same weight, that is two times that of the HHP anchors.

So if we’re getting double the holding power, does that mean we can use an anchor that is half the weight? Not necessarily. Nor can you expect another doubling of holding power by doubling the weight of an SHHP anchor.

Despite the sales pitch that the new anchors have greater holding capacity pound-for-pound, the anchor makers are suggesting that you replace your old CQR with the same weight new anchor. It appears that manufacturers are, in effect, doubling the historic safety factor. And for a cautious sailor, there is nothing wrong with this.

However, consider the advice that is often repeated on internet forums, or the local scuttlebutt, that cruising sailors should increase one size over the makers recommendation. So instead of a 33-pound Rocna for your Tartan 37, you buy a 44-pound Rocna-now with potentially three times the safety factor of an old school anchor. Apart from the added significant expense, this obsession with upsizing – more anchor, more chain, bigger windlass-can also add potentially unnecessary weight and concentrate it in the bow.

So what do we really get with that bigger anchor? There is an idea that if you double weight of an anchor you will double holding power. Except with extra-large commercial anchors and some specific tests, we’ve found no data to support this.

No independent test, as far as we know, has taken a series of different sized anchors of the same design and tested them in the same seabed for ultimate holding capacity. Tests have been conducted on commercial oil rig anchors like the Bruce, and the best scaling is about 90 percent-double weight and you increase hold by 1.8 times.

The only recreational anchor that we are aware of that has undergone some testing to determine the relationship between weight and holding is Fortress (in mud only, see Anchoring in Squishy Bottoms, PS February 2015 ). An analysis of all their tests on a complete range of their anchor sizes suggest that if you triple weight you increase hold by slightly more than two times, approximately an 80 percent efficiency as size is scaled up.

Ultimately, this means that when someone tells you they can calculate the increase in holding power as you move up in size, be careful not to read too much into this conclusion. For one, the ratio used deserves close scrutiny. Surely, the bigger anchor will provide better holding-but how much? This hard to quantify, even with computer modeling. And no matter how accurate your calculation-a ratio based on performance in one type of bottom might not apply in another.

One reason you can’t claim that doubling the weight doubles the holding is that as anchors increase in size, the stress on the construction increases. To compensate for the increase in stress, the steel thicknesses must be increased – and more steel weighs more. So in an anchor whose holding power relies greatly on surface area and how it is distributed, adding more weight doesn’t necessarily result in a commensurate increase in surface area that provides holding power.

And as we’ve shown in our past tests-anchor dimensions (especially the fluke area) and shape can play a significant role in performance. It might be possible to double weight and double the holding power without beefing up the steel, but the resulting anchor would be less strong relative to its designed holding power.

Weaker construction might not matter on an over-engineered anchor. However, we have seen how the use of inferior materials has resulted in anchors that bend more easily at designed loads (see Anchor Tests: Bending More Shanks, PS May 2013 ).

Anchor Angles

In past reports, we’ve discussed in detail how anchor design can impact holding, especially with the new generation anchors ( see An Inquiry into Anchor Angles, PS February 2017 ). As you consider which design best suits your needs, here are some things to consider.

Fluke/shank angle. The fluke/shank angle is the angle between fluke and shank. It is one of the determining factors in how quickly and deeply an anchor sets. For a simple design with flat plate fluke and a straight shank (like a Guardian) the angle is a line down the center of the shank to the hinge and then along the fluke. In shanks with curves or angles, the first line is usually drawn from the shackle pin to the point there the shank meets the fluke.

For three-dimensional flukes (as found in most new generation anchors), you have to estimate where the top of the fluke plate lies. The ballast chamber or shank support that might protrude from the sole, such as with Spade, or Vulcan anchor should not be used to determine shank/fluke angle.

It is the fluke top surface that is important. In previous tests we reported that in thin mud an anchor with a fluke angle of around 45 degrees will outperform an identical anchor with its fluke angle set at 30 degrees. But a firmer sand seabed is entirely different, and research demonstrates the ideal fluke angle for a typical sand bottom is around 30 degrees (see Small Anchor Reset Tests, PS February 2013 ).

Fluke-seabed angle. This is the angle of the fluke to the seabed during the phases of anchoring-most importantly, during the initial penetration into the bottom, and when the anchor is set.

Penetration angle. When an anchor is aligned ready to set, or engage with the seabed (it might need tension on the rode to achieve this) then the fluke will usually be at an angle of 60-70 degrees to the seabed. Commonly the anchor is on its side.

Setting angle. Once the anchor starts to penetrate it will self align and the fluke plate tend quickly toward its setting angle, usually of about 30 degrees. It is coincidence that the fluke/shank angle and setting angle are similar though most anchors tend to show the similarity of the two angles. Center of gravity can have a great effect on penetration angle. This is why many new generation anchors, like the Ultra, have weighted flukes. Having a 30-degree fluke/shank angle is irrelevant if the center of gravity is in the wrong place.

Shank length

If you imagine a Fortress with a shank/fluke angle of 30 degrees but a shank three times longer than its original design, then you can visualize how the anchor will probably simply slide along the seabed when tensioned. The throat opening will be too small. Similarly if you chop the shank in half, the toe of the anchor will simply scrape along the seabed. In both case the anchor will find difficulty in engaging because the penetration angle will be wrong.

Are the makers of new generation anchors over-stating the need for bigger anchors, thus requiring boat owners to pay much more than they might need in order to be secure at anchor? Possibly. Would going with a larger-than-required anchor actually hurt your anchors performance? Unlikely. As is often the case with our anchor reports, it is hard to come with some firm answers regarding both of these questions. Anchor studies are fraught with variables.

In our view, it is no crime to go up one size over the manufacturers recommended size, if your boat and crew can handle it. The anchor may require more reverse throttle to set, but ultimately, it should provide the holding you require. Likewise, it is reasonable to assume that the anchor makers guidance for sizing is reasonable. However, if an online advocate starts telling you that youll get x times more holding power by going up one size, ask him for the data.

Extra weight in an anchor is your insurance policy. Yes, you can almost always get more security with the heavier anchor, but whether or not you will every need that extra holding power is not conclusive. In our view, conservative sizing is added insurance-but until the data is in, we remain skeptical of any absolute claims that attempt to quantify the advantages of more weight when choosing an anchor.

Based on average recommendations from leading anchor makers, the weight savings of upgrading to a second generation anchor doesn’t really pay off until you get into the larger size vessels.

In an anchor whose holding power relies greatly on surface area and how it is distributed, adding more weight doesn’t necessarily result in a commensurate increase in surface area that provides holding power. To compensate for the higher loads, the steel must be thicker, resulting in different surface area/weight ratios.

• As fluke size increases, so do the loads. But if the construction isn’t beefed up to handle the loads, the result is failure. Flat plate steel in this Danforth fluke sheered.
• The shaft of an Excel anchor bent during veer testing.
• The flat flukes of the Bugel anchor makes it easy to calculate the shank-fluke angle.
• Here a Rocna anchor is in the initial setting angle, still capsized on one side, with not enough of its toe is dug into the soil to dig in. Bottom shape and center of gravity (some designs are weighted to control CG), helps to determine this angle.
• This Manson Ray anchor has rolled upright and assumed the angle of penetration that will help the anchor to bury into the bottom.

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When sizing an anchor or anchor rode, it’s useful to have starting point and to think of the whole system. This is a table developed by American Boat and Yacht Council (ABYC) to approximate the expected load on the anchor and the anchor rode for given wind speed and boat length. The complete table appears in Section H-40 of ABYC’s Standards and Technical Reports for Small Craft available at abycinc.org.  The below table was created more than 50 years ago and it is not clear exactly how it was derived. After comparing this data in this table to work that has been done since we come to the conclusion that the values presented here represent loads expected on the anchor rode if anchored on chain only without the use of the snubbing system.  And using a line rode or and adequately designed snubber you can reduce the loads by a factor of 3, by eliminating the shock loads. This is an argument for why its so important to use a snubber but when sizing anchor rode or your anchor, it is important to consider loads as stated in the table. The reason is that we can not rely on the integrity of a snubber in a storm.  Should the snubber fail, the integrity of the rode should be sufficient to handle the loads without the snubber.

The ABYC Horizontal Working Load (lbs) Table

How do you intend to use your boat? Do you sail only on calm days with fair weather (Lunch Hook) or are you outfitting for an adventure (Storm) where you might be exposed to hazardous weather at anchor? For example, if you are outfitting a 35 foot boat for you should size the working rode and anchor to safely handle loads up to 1,800lbs if planning a cruising adventure, but the same margin of safety is not necessary if operating day trips from the safety of a marina.

When making sizing recommendations we are generally referring to the needs of a cruising boat spending most of its time on anchor, in doing so we try to envelope high sustained winds (45 kts) and assume poor holding conditions (low viscosity bottoms).  Some may think these recommendations to be too conservative especially when compared to sizing tables from other manufacturers. Companies often make claims of superior anchor efficiency, stating that their small anchor X will outperform a much heavier anchor from their competitors and often use sizing charts as a marketing tool to that end, recommending anchors and anchor systems that are dangerously undersized for their intended use.  Comparing surface area can be a good judge for potential holding capability.  Our anchor sizing recommendations are presented in the table below:

ANCHOR SIZING GUIDE (Click to enlarge)

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Anchor Selection: A Guide to Types and Sizes

Anchoring is a crucial aspect of boating, and the right anchor can provide stability, safety and peace of mind for any sailor. Choosing the correct type and size of anchor is essential, as it can greatly impact your overall experience on the water. This guide will outline the various types of anchors available, their ideal uses, and how to choose the right size for your boat.

Understanding the Purpose of Anchors

Anchors serve multiple purposes in boating:

• Holding power : Anchors are designed to provide holding power by digging into the seabed and creating resistance, preventing the boat from drifting.
• Temporary mooring : When a boat needs to be stationary for a short period, an anchor is used to secure it in place.
• Emergencies : Anchors can serve as a safety measure in emergencies by helping to control your boat’s movements in rough weather or if the engine fails.

Types of Anchors

There are several types of anchors to cater for various boating requirements and environments. The primary ones include:

Plow Anchors

Originally designed for large ships, plow anchors resemble a plowshare and offer excellent holding power in most bottom conditions, especially sand and mud. They work by digging into the seabed and maintaining a consistent grip. Plow anchors are popular among cruisers due to their adaptability, and they can handle a variety of wind and current changes.

Danforth Anchors

Also known as fluke anchors, Danforth anchors boast superior holding power in proportion to their weight. They’re characterized by their flat, sharp flukes and long shank that allows them to dig into soft substrates like sand and mud. However, Danforth anchors may struggle with rocky bottoms and can be challenging to set in grassy or weedy seabeds.

Claw Anchors

Claw anchors, also known as Bruce anchors, have three claws that provide holding power in a variety of bottom conditions. Due to their versatile design, they re-set easily when the boat’s position changes and can function with shorter scope, which is the anchor rode (chain or rope) payed out relative to the water’s depth. These factors make claw anchors popular among boaters, though their holding power may be less than that of plow or Danforth anchors.

Mushroom Anchors

Mushroom anchors are useful for small boats in relatively calm conditions. As the name suggests, they’re shaped like a mushroom and utilize their weight to create a suction effect, embedding themselves into soft bottom substrates like silt or mud. However, they generally offer limited holding power in stronger currents or wind.

Choosing the Right Size Anchor for Your Boat

Selecting the appropriate size anchor for your vessel involves considering factors like boat weight, size, and the windage (resistance to wind). Generally, anchor manufacturers offer recommendations based on boat length, but it’s essential to factor in your specific boat’s requirements and typical anchoring conditions.

Anchor Weight

Anchors are typically sized by weight, ranging from a few pounds for small vessels to several hundred pounds for large yachts. The rule of thumb is that the heavier the boat, the heavier the anchor should be. However, it’s important to consider the type of anchor you’re using, as the holding power varies across anchor designs.

Boat Length

Boat length is another crucial aspect to consider when selecting an anchor size. Consult manufacturer guidelines on their recommendations for anchor sizing based on boat length.

Chain and Rode Size

The anchor rode, which connects your boat to the anchor, is critical for holding power. The scope, typically measured in a ratio of the rode’s length to the water’s depth, is an important factor for the anchor’s performance. A common recommendation is using a 4:1 scope for temporary mooring and a 7:1 scope for overnight anchoring. Ensure the chain (the section of the rode closest to the anchor) is of suitable size and strength to prevent it from breaking under strain.

Final Thoughts

When selecting an anchor for your boat, it’s essential to consider the type, size, and the conditions in which you’ll be anchoring. Consult manufacturer guidelines and conduct thorough research on the options available to make an informed decision. A properly sized and suited anchor will offer peace of mind, ensuring your vessel remains securely moored during your adventures on the water.

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How to Pick a Boat Anchor: The Guide to Types, Sizes & Weights

October 20, 2023

Lakes can get choppy, and river currents can drag you along when you'd rather stay put. Having the right anchor on your boat is crucial, especially if you're busy staging for a wakeboard or ski ride .

But what type and size of anchor is best for your setup?

Types of Boat Anchors

Let's look at the most popular types of boat anchors, and look at some charts to figure out what size and weight anchor is right for you.

Fluke Anchors

Also known as a Danforth anchor, the fluke anchor is favored by lake and river boat owners for its lightweight design and excellent holding power in soft bottoms.

Fluke anchors have a rotating bar that connects the anchor to the line. Their forward-heavy profile allows the flukes to drive straight down into sand or mud. As line is laid out, the bar swivels into a horizontal position, providing good scope.

• Boat Size: 30 feet or less
• Best For: Lakes, rivers, mud and sand
• Bad For: Rocks, debris, coral, strong currents

Plow Anchors

Also called a delta anchor, the plow anchor is one of the most popular anchors on the boat market. It's simple and effective, capable of providing reliable mooring in all water conditions and most beds.

Plow anchors dig into the surface below and they provide high holding power. They set quickly, which makes them an excellent choice when strong currents and winds could otherwise quickly move your boat.

But plow anchors' large, flat fins can get stuck in debris and large rocks, so it's best to stick to softer bottoms.

• Boat Size: 70 feet or less
• Best For: Sand, mud, grass bottoms, strong winds
• Bad For: Rocky bottoms

Claw Anchors

Also known as a Bruce anchor, the claw anchor is similar to a plow anchor: It sets quickly and digs into soft bottoms, providing good holding power against currents and wind -- though not as well as a plow.

Because claw anchors use smaller pins, they're better suited in gravel and rock, affording a lower risk of catching and getting stuck where a plow anchor might get hung up.

Digger Anchors

The digger anchor excels at providing high holding power in gravel and rocky bottoms, even with strong currents and high wind. It uses a rod that partially rotates, while limiting the angle of the anchor line's scope.

As current and wind pull on the boat, the rod's limited angle pulls on the anchor's claws, pushing them further into the bottom. The digger's thin, long claws work great in virtually all bottom, including gravel and small rocks -- just avoid large debris, as the limited angle of the anchor rod prevents it from being pulled back out of a snag effectively.

• Boat Size: 40 feet or less
• Best For: Sand, mud, grass, gravel, strong winds
• Bad For: Bottoms with large debris

Navy Anchors

The classic, heavy, big navy anchor excels at providing high holding power in all waters and conditions. Its size and shape make it suitable for rocky bottoms and debris fields, as it has little risk of getting snagged.

The only problem with a navy anchor is that its benefits can become problematic for smaller vessels: Because navy anchors are large and heavy, they can be difficult to stow, and they add plenty of weight to the hull.

• Boat Size: 20+ feet
• Best For: All bottoms, currents, and weather
• Bad For: Small, light boats

Mushroom Anchors

The mushroom anchor is made for small vessels in relatively calm waters with soft bottoms. It relies on suction and sinking into sand, dirt, and mud to provide holding power. These anchors are typically found on light, electric motor-powered boats, kayaks, and dingy boats.

• Boat Size: 12 feet or less
• Best For: Soft bottoms free of rock
• Bad For: Large boats, heavy currents, rocky bottoms

River Anchors

Like the mushroom anchor, the river anchor is also intended for small vessels in lakes and rivers -- but with one exception: The river anchor works well in rocky bottoms and beds filled with debris. The wide, flat flukes work best when they can grab hold of objects on the floor. River anchors work well enough in soft bottoms, albeit with less holding power than a mushroom.

• Best For: rocky bottoms and debris fields
• Bad For: Large boats, heavy currents

Choosing The right Size Anchor

When selecting a boat anchor, it's important to consider the following factors:

The size and weight of your boat will determine the size and weight of the anchor you need. As a general rule, the heavier the boat, the larger and heavier the anchor should be.

Water and Weather

The type of weather and currents you encounter will influence your anchor choice. Different anchors perform better in different conditions, so it's important to choose one that suits your boating environment.

Conditions of Water Bed

The floor your anchor rests upon can vary wildly. Some lakes and rivers have rocky bottoms filled with debris, while others have soft silt or sand. Picking the wrong setup could mean you wind up drifting, or worse, cutting line because your anchor got stuck at the bottom.

Anchor Weight vs. Boat Size Chart

The chart above is a general guideline for selecting the appropriate anchor weight for your boat. Conditions on the water, and the weight of your boat -- regardless of its size -- could mean you need a heavier anchor.

Anchor Chain vs. Rope

When it comes to anchoring, you'd think chain is far superior to rope. But chain really only provides two advantages: It adds holding power, helping to keep your boat moored in one spot in rough water and strong currents, and it resists chafing -- it won't suffer damage from being dragged along debris and rocks.

Chain is heavy, though, so it adds weight to your craft when not being used. This isn't a concern on large, sea-going vessels. But you probably don't want that added weight when you're cruising around on the river or lake, especially when towing a wakeboard, tube, or skis.

Chain also rusts, even with regular maintenance, and it's expensive. Nowadays, synthetic anchor rope is tough and abrasion-resistant, and it withstands water and sunlight incredibly well. It's also lightweight relative to its strength, and it takes up much less space than chain.

The most effective setup combines a bit of chain near the anchor, with rope making up the rest of the line. Just a few feet of chain is needed to ensure your anchor is properly seated. This bit of chain also improves the scope of your line. "Scope?" You, say? Read on.

It's All About Scope

Rope alone will provide as much holding power as chain, so long as your scope is correct. Scope measures the ratio of the length of deployed rope (or chain) to the height from the ocean, lake, or riverbed to the anchor point on the boat.

The minimum effective scope you need to properly moor your vessel with any anchor and line is 5:1. That means if the depth from your boat's topside to the underwater floor is 5 feet, you need 25 feet of rope laid out below. This affords about 75% of the maximum holding power of your anchor and line.

A scope of 10:1, laid perfectly flat on the bed below, provides 100% holding power. Using the same 5 foot depth, you'd need 50 feet of anchor rope or chain laid out for max holding power.

Need a new anchor setup? Check out our boat anchors and anchor lines !

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What Size Anchor Do I Need? (Anchor Size Chart)

When it comes to boat safety items, an anchor is non-negotiable. Your anchor size roughly depends upon your boat size, type, wind speed, anchor type, and anchoring conditions you encounter.

To be precise, pinpointing the exact anchor size for your boat can be difficult. Nevertheless, it is always a good idea to follow the rough guidelines provided by your anchor manufacturer.

For your convenience, we’ve compiled all the information you need to figure out the right size of anchor for your boat in this post. Let’s begin!

Table of Contents

What Factors to Consider Before Buying a Boat Anchor?

Types of boat anchors, anchor size chart, what size anchor do i need, what are some common anchoring mistakes.

1. Holding power

The holding power of an anchor is the pull force it must withstand in order to hold the boat of a given weight in place.

Holding capacity depends upon the ability of the anchor to dig, the soil measurements, and the shape of the anchor . Holding power also varies with environmental factors such as wind speed.

2. Anchor weight:

Besides holding power, the anchor weight is also a primary factor you should consider. The anchor must be heavy enough to be able to drag through the bottom so that your vessel stays put in a single place.

In fact, many suggest always taking two anchors on board with you at all times, especially if you anchor your boat overnight; one, a simple hook style anchor for calm water and weather conditions, and a heavy one that assures your boat safety even during stormy and turbulent conditions.

Nevertheless, many new generation anchors today rely on the design that offers the best holding power and not really on the weight of the anchor.

3. Type of seabed:

Some types of anchors are efficient for sandy or muddy seabed, while others might be the best in the case of rough and rocky bottoms.

Almost all types of anchors have impressive holding power in hard sand bottoms. However, in mud bottoms, anchors need to penetrate high in order to reach the bottom material.

Likewise, weed bottoms are truly challenging to penetrate for anchors. Therefore, the anchor weight plays a critical role in such a seabed type.

Overall, you must be aware of the seabed types that you’ll encounter along your voyage to be able to choose the right design and sized anchor for your vessel.

1. Folding Grapnel:

Folding grapnels features multiple tines to grab structures and are great to anchor to an area with rough or rocky bottom. These anchors are great for small vessels, inflatables, and jet skis and are recommended by many as secondary or emergency anchors.

2. Reef Anchors:

As the name suggests, reef anchors are great for coral reefs and rocky bottoms. Many boaters choose to hand-weld and DIY reef anchors .

3. Plough anchors:

Plough anchors have a single penetrating point attached to the central shank and are ideal for sandy, muddy, and weed bottoms. You might notice arched shank in modern plough anchor designs. As long as it gets a good grip, this anchor type is also great for rocky bottom uses.

On the other hand, plough anchors might not be the ideal anchor for loose bottoms, as it only gets dragged along the boat without any resistance.

4. Claw anchors:

Claw anchors have a broader scoop shape than plough anchors and are suitable for anchoring in a variety of sea beds. It is ideal for sandy and muddy sea bottom but also performs decent enough in rocky bottoms. Nevertheless, it isn’t a great anchor candidate when it comes to loose sand bottoms.

5. Fluke or Danforth anchors:

Fluke anchors feature two triangular-shaped flukes attached to the central shank to bury onto the sea bed. Due to its simple design and lightweight character, it is undoubtedly a great choice for small crafts.

The small gap in between the flukes in the Danforth anchor allows better grip onto the rough sea bed. Although the orientation of the flukes is changeable depending upon the seabed material, the ideal angle for maximum efficiency is 30 degrees.

6. Mushroom anchors:

Another great anchor for small vessels and dinghies is the mushroom anchor. Small mushroom anchors are ideal if you often anchor your boat to a river bottom. On the other hand, large mushroom anchors are used for mooring purposes.

7. Spade with roll bar anchors:

Distributed by brands such as Manson and ROCNA, a spade with roll bar anchors is designed to set fast onto any type of sea bed with impeccable holding power.

For your convenience, we’ve done all the research for you. Here are some common anchor types used in the US and the anchor weight recommended for them depending on the boat length.

Remember to take this list only for reference purposes and research for the accurate and updated recommended anchor size listed by your manufacturer. And, when in doubt or during stormy conditions, always go a size higher.

Note: Unless specified otherwise, the chart assumes an average boat weight , average bottom conditions, and typical environmental conditions, including wind speed. In the case of exceptionally long and heavy vessels, many brands such as Lewmar recommend the clients follow the relevant Classification Societies for instructions.

The standard calculation is 1 lb of anchor for each foot of the boat. Once you’re ready with this basal value, you can then adjust the anchor size by taking the instructions below to size up or down the anchor.

As per the rope, use three-strand nylon, and the minimum scope for your anchor must be 5:1. The scope value should be around 7:1 in case of heavy vessels.

The boat anchor scope is the ratio of the deployed anchor rode length to the depth of the water from the deck height to the bottom of the water body.

Likewise, the 6 ft chain for every 25 ft of water depth rule is also the golden standard. Moreover, anchors require at least one ft of chain every one ft of boat length for maximum efficiency.

Up your boat anchor size, regardless of the manufacturer’s recommendation, if you relate to any of the following scenarios.

• Your anchor rode is relatively lightweight.
• Your boat is relatively heavier than other boats with similar dimensions.
• Your boat is usually anchored in an area where weather change is unpredictable and quick.
• Your boat is big and wide relatively.
• The anchored area has a lot of windage.
• You’re planning an offshore sea voyage.

On the other hand, when it comes to sizing down your anchor size, the typical suggestion is that you don’t do it unless and until you check these conditions.

• You’re well aware of what type of seabed you will be anchoring your boat in.
• You never anchor your boat for a long duration or overnight.
• The wind speed of your sailing area never exceeds 10 knots.
• Your anchor rode is too big and heavy for your lightweight boat.

Now that we all know how to choose the right boat anchor size for your boat let’s have a brief look at a few common mistakes sailors repeatedly make while anchoring their boat.

• Losing anchor in a trip is definitely not a new piece of news to experienced sailors. Many forget to secure the anchor line to the boat and simply throw the anchor into the water body.

Given this, many experts recommend sailors at least own two anchors on board with them during their journey.

• The anchor line can be messy to deal with, given how long they are. Often, sailors or the person on the foredeck make the mistake of letting the anchor go with their foot wrapped in the rope. That’s a pretty risky scenario.

Remember that when it comes to boat anchors , the bigger, the better unless the weight of the anchor is too heavy for your boat or it is too difficult to retrieve manually.

Also, for multihulls, many brands, including Spade and Rocna, suggest the buyers to up the size than recommended in the guide.

We hope you could form a clear idea on your head regarding the sizing of the boat anchor you require after reading this post. Let us know in case of any more queries!

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