A proper anchor rope is essential without that there is no use of having an anchor in your boat. You should consider so many things while buying an anchor rope.
The good rope for anchoring a boat is nylon rope (three-strand) because it is strong and flexible, and nylon will not float in water. You should not buy any rope that floats in the water because it may cause any issues to other boaters if it floats in water.
If you are thinking of choosing an anchor for your boat, then click my article on Choosing a perfect anchor for your boat (don’t worry, it will open in a new tab). In that article, I mentioned the best anchors based on the bottom types.
Consider these things while buying an anchor rope
The essential thing you should consider while buying an anchor rope is the material of the rope. Whenever you are buying a rope, don’t buy polypropylene rope. The issue with polypropylene rope is it will float in the water, which may cause some problems to other boaters.
The first thing you should consider while buying a rope is to check whether it will float in the water or not. If it is not floating, then it is fine. If the rope is floating in the water, it will create problems for other boaters.
Polypropylene rope (pool rope or ski rope) is a very lightweight synthetic so, it will not sink in water. Since it doesn’t absorb water, it resists rot, mildew, oils, acids, etc. Polypropylene can stretch when under load and can be uncomfortable to handle since it is stiffer than natural fiber.
Like, the rope may be caught up in some other boat propeller, it may cause a severe problem for you or to your boat. Nylon would be the best material for a rope because it will stretch, if any wave comes, nylon rope will stretch absorb the shock, and goes back to normal.
Any rope that doesn’t float in the water is good for anchoring the boat. The polypropylene will not absorb the water so, it will float in the water, causing problems to other boaters.
If you are anchoring your boat in a crowded area surrounded by boats, then you shouldn’t use the rope which floats. If you won’t go to a crowded area, then you can buy any rope.
Now, that you have selected the material of the rope. Let us see which rope is better (solid braid or three-strand rope).
What type of ropes you should buy for anchoring a boat?
There are two types of ropes used for anchoring a boat.
- Solid braid rope
- Three-strand rope
Both of the rope types are good for anchoring the boat, each type of rope has its advantages and uses. First, let us see about the solid braid rope, and then we will see a three-strand rope.
Advantages of solid braid rope while anchoring a boat
The advantages of solid braid rope are it is flexible and strong. Knots with a solid braid rope is much more effective than any other ropes. But the solid braid is a bit more expensive than a three-strand. The only problem with the solid braid is it won’t slice up as 3 strand rope.
The main advantage of the solid braid rope is the elasticity. It is more elastic than other ropes (but, not more elastic than three-strand). The nylon will absorb all the shocks from the waves in the sea and stretches accordingly.
Nylon braided rope is very suitable for various uses. Nylon rope will stretch when sudden pressure is applied, but it will not do so at the expense of its durability. This quality makes it an excellent option for construction or climbing.
Most people prefer to use a braided rope for mooring lines primarily because it has a better feel in the hand. But, a solid braid can be used for anchor rope as well.
In solid braid rope, there are two types of ropes
- Single braided rope
- Double braided rope
The difference between a single braided and double braided rope
The difference between a single braided and a double-braided rope is a double-braided rope is a single braided rope, which is braided on the top (exterior) with another layer. The inner braid rope is made from a stronger material, while the outer is a more abrasive resistant material.
Which one is more efficient, Single braided or double braided rope?
Double braid rope is more efficient than a single braid because the inner braid rope is made from a stronger material, while the outer is a more abrasive resistant material. So, combined will increase the strength of the double braided rope. You can use a double braid for anchoring a boat.
If you thinking to buy a solid braid rope for anchoring your boat, then the better option would be a double braided rope.
Image is linked to Amazon or click here (don’t worry, it will open in new tab). This is the best double braided rope for anchoring your boat.
Advantages of three-strand rope
The advantages of a three-strand rope are these ropes are a bit less expensive than a solid braid. We can slice the three-strand rope better than a solid braid rope. Three-strand rope gives more grip than a solid braid rope and more elastic than a solid braided rope.
Twisted rope is generally preferred for anchor rodes because of its slightly greater elasticity. I find that it’s a bit easier to get a good grip on wet three-strand than wet braided rope.
- It costs less than a solid braid
- Easy to splice
- More elastic (stretches more)
Image is linked to Amazon or click here (don’t worry, it will open in new tab). This is the best three-strand rope for anchoring your boat.
Check this boats website on the ropes and how to choose based on the working strength click here (don’t worry, it will open in new tab).
What length and size rope you should buy for anchoring a boat?
What rope size you should buy for anchoring a boat?
The perfect rope size for an anchor is a 3/8″ (0.9525 cm) diameter with 250 feet (76.2 m) or more in length is best for a boat under 30 feet. If your boat is small, no problem, it is better to protect your boat with some extra strong rope. It is good to have extra length, don’t buy too short one.
Many people will suggest following the rule of thumb (1/8 inch rope size for every 9 feet boat) for selecting the size of the rope. But, the rule of thumb is not good for selecting a rope size for a small boat.
Let us consider you have a 9 feet boat. According to the rule of thumb, you need to choose 1/8″ (0.3175 cm) diameter rope for anchoring a boat. 0.3 cm diameter rope size is a very small rope for anchoring a boat.
If you have a bigger boat (above 30 feet in length), then follow that rule of thumb for selecting the rope size. If you have a small boat (less than 30 feet in length), don’t follow the rule of thumb for selecting the rope size.
If your boat is less than 30 feet in length, then buy a 3/8″ rope for anchoring your boat. It is good to protect your boat with some extra strong rope, rather than a small rope. It is good to have extra length, don’t buy too short one.
How long length rope you should use for anchoring a boat?
The length of the rope depends on the depth of the water, it depends on what depth you will drive the boat. There is a rule of thumb for selecting the length of the rope.
If you are using the boat in calm water and there are no huge tides, then 5:1 scope is sufficient. For every one meter in length, you should use five meters length rope. This will be enough for small boats or dinghies.
But in general, if the water depth is more, then go for 250 feet. If the water depth is less, then go for 150 feet or 200 feet length ropes. The rule of thumb for selecting a rope length won’t work properly because the depth changes from place to place, and it is hard to tell.
So, buy extra length rope based on depth and scope. If you are using a boat under 30 feet, then go for 250 feet length rope for anchoring.
This ratio (5:1) will work if the weather is calm and there no huge tides.
| Water depth (in meters) | Rope length (in meters) |
| 1 m | 5 m |
| 2 m | 10 m |
| 5 m | 25 m |
| 10 m | 50 m |
| 15 m | 75 m |
If the weather is rough, then you should change the ratio (8:1) like that.
| Water depth (in meters) | Rope length (in meters) |
| 1 m | 8 m |
| 2 m | 16 m |
| 5 m | 40 m |
| 10 m | 80 m |
| 15 m | 120 m |
Check my article on the recommended rope for anchoring a boat click here (don’t worry, it will open in new tab). Some of the rope brands I like are norestar rope, which is a very good rope.
I like what Norestar has made. Especially when it comes to a boat under 30 feet, this 3/8″ Norestar rope is perfect for anchoring. The cost of the product is also not expensive, it is reasonably good. It is available in the range from 150 – 600 feet long(45m – 182m).
| Rope diameter (inches) | Load Limit (lbs) | Boat length (feet) |
| 3/8″ (0.9525 cm) | 4500 lbs | up to 27 feet |
| 1/2” (1.27 cm) | 8300 lbs | up to 36 feet |
| 5/8″ (1.5875 cm) | 13400 lbs | up to 45 feet |
| 3/4″ (1.905 cm) | 19100 lbs | up to 54 feet |
Okay, now let us talk about chains
What chain size you should use for anchoring a boat?
The chain size you should use for a boat is half the size of the rope (diameter) you are using for anchoring your boat. This is the rule of thumb for selecting the anchor chain size for a boat.
Assume if you are using a half-inch(1/2″) anchor rope for your boat, then you need to use half the size of the rope. That is quarter-inch(1/4″) for anchoring the boat.
| Rope size(in inches) | Chain size(in inches) |
| 1 inch | 1/2 inch |
| 3/4 inch | 3/8 inch |
| 3/8 inch | 3/16 inch |
| 5/8 inch | 5/16 inch |
| 1/2 inch | 1/4 inch |
| 1/4 inch | 1/8 inch |
But, if you are using a small size rope-like 3/8 inch, then you should use a 3/16 inch size chain for a boat. Which might be okay for many boats. But for some boats, it might be not enough.
Like, for many boat boats 3/8 inch rope would be a sweet spot, even though if your boat is small, having a 3/8 inch rope will give extra protection. Similarly for a chain, 3/16 inch chain would we a sweet spot for many boaters.
3/16 inch chain is 0.4 in cm, which will be good enough for many boaters. Don’t decrease the size beyond 3/16 inch because 0.4 cm itself is a small size chain for a boat. If you decrease more using that size chain would be no use for a boat.
This is how you can choose the chain size for your boat.
Types of anchor chains
There are basically three types of anchor chains
- HT G4 chain (HT chain or G4 chain or G43 chain)
- BBB chain
- Proof coil chain
We can call this chain as HT chain or G4 chain or G43 chain. This HT chain is much stronger than the rest(BBB and Proof coil chain).
The difference between an HT chain and BBB chain
The difference between the HT chain and BBB chain is in its width. If you take 1/4 inch chain, then the width of the HT chain is 0.99 inches and the width of the BBB chain is 0.96 inches. That is the difference between the HT chain and the BBB chain.
What type of chain you need to use depends on the windlass type. Whenever you buy the windlass, they will give what chain size you should use with the windless. Don’t use the chain size that is different from the given chain size on the windlass.
Just use the chain size that is given on the windlass. If there is any difference in chain size, it might damage the whole windlass, replacing the whole windlass is more expensive than buying an appropriate chain size.
Watch this video on windlass chains.
Why do we need to galvanize the anchor chain?
We need to galvanize the anchor chain because the chain is made up of iron which will rust when exposed to water. Over time rust will corrode an iron part to the point of failure. The Galvanized chain is a regular chain that has been coated in zinc to make them corrosion resistant.
After buying the chain, galvanize it with zink. If you galvanize the anchor chain properly, then the chain won’t corrode much. If you are using the boat in seawater, then galvanize the chain for long life.
There is another option for using a rope with the chain as a combination of both for anchoring a boat.
Combining anchor chain with rope
You can combine both the chain and the rope, and you can use them for anchoring a boat. Generally, you will use a chain (which is of boat length) for connecting the anchor and the other end will be connected to the rope.
The idea of using the anchor chain at the end of the anchor is to avoid the rope from the damage. The anchor rope some times will get damaged because after anchoring the boat, the boat will be moving due to tides or winds.
If you are using only the rope for anchoring your boat, then the part of the rope which touches the ground will rub the ground whenever the boat moves due to tides or winds, then the rope will get damaged.
To avoid that damage to the rope, we will connect a small chain (length maybe the size of your boat) at the anchor end of the boat. Then the other end of the chain is connected to the rope (to thimble).
The Thimble is like a hook, which can be connected to the chain by using a shackle. Now after connecting the chain, the part which touches the ground will be a chain. Nothing will happen to the chain.
Key takeaways
- Whenever you are buying a rope, don’t buy polypropylene rope. The issue with polypropylene rope is it will float in the water, which may cause some problems to other boaters.
- 3/8 inch rope size(diameter) will be good for many boats under 30 feet and don’t decrease the rope size than 3/8. Having a bigger size rope will give extra protection to your boat.
- Chain size should be half the size of the anchor rope size(diameter).
- HT chain is the hardest chain among the rest (BBB and Proof coil chain)
- Don’t follow the rule of thumb for selecting the anchor rope size, if your boat is less than 30 feet in length.