The Ultimate Guide To Docking: Perfecting Your Boat's Lines

Dock lines, also known as mooring lines, are an essential piece of boating equipment that ensures your boat remains safe and secure while stationary. The number of dock lines you need depends on the size of your boat and the conditions it will be subjected to. As a general rule, a boat should have a minimum of six dock lines: two bow lines, two stern lines, and two spring lines. The length of the lines depends on how and where you moor your boat, with bow and stern lines typically measuring two-thirds of the boat's length, and spring lines equalling the boat's length.

Dock line types: transient vs. permanent

Dock lines are an essential piece of boating equipment that keeps your boat safe and secure while stationary. There are two main types of dock lines: transient and permanent.

Transient Dock Lines

Transient lines stay on the boat. They usually consist of an open end that’s placed over the dock cleat and the bitter end that’s adjusted in the boat. These lines are not cut to fit, and you’ll usually have some excess to account for variances at different docks. Transient lines are also known as non-permanent lines. They will not have loops on both ends of the line as they need to be drawn to various sizes depending on the dock they are on.

Permanent Dock Lines

Permanent lines stay at the dock and are cut to length. They don't require adjustment. Unlike transient lines, they must be protected from chafe, the enemy of all lines in constant use. This calls for leather, rubber or fabric chafe gear where the line passes through the chocks, and possibly a chafe sleeve on the eye where it goes around the cleat on the deck.

Dock Line Materials

Dock lines are typically made from nylon, a synthetic fibre that has a superior combination of strength and stretch. Nylon is strong, durable, and stretchy. It is also lightweight and easy to handle. However, it does shrink and loses about 10-15% of its strength when wet. Polypropylene is not recommended as it degrades quickly in the sun, doesn't have the required level of stretch, and has a low breaking strength.

Dock Line Weave Types

Dock lines most commonly come in three weave types: three-strand, braided, and double braided. Three-strand is abrasion-resistant, stretches more, is easier to splice, and is less expensive. Braided nylon is stronger, easy on the hands, and looks good. Double-braided nylon is the strongest, easy to handle, abrasion-resistant, has controlled elongation, and looks good.

Dock line materials: nylon vs. polypropylene

When it comes to choosing the right material for your boat's dock lines, nylon and polypropylene are two of the most commonly discussed options. Here's a detailed comparison between the two to help you make an informed decision:

Nylon Dock Lines:

Nylon is widely regarded as the best choice for dock lines due to its unique combination of strength, stretch, and sunlight resistance. Here are some key advantages of using nylon dock lines:

• Strength and Stretch: Nylon is known for its exceptional strength, making it ideal for securing boats of various sizes. Additionally, its ability to stretch up to 15% of its length helps absorb shock and reduce stress on cleats and deck hardware when your boat surges against the dock.
• Sunlight Resistance: Nylon exhibits excellent resistance to ultraviolet (UV) degradation from sun exposure, ensuring a long lifespan for your dock lines.
• Fuel and Chemical Resistance: Nylon stands up well to fuels and chemicals commonly used on or around boats.
• Ease of Handling: Nylon lines are lightweight and easy to handle, making them a boater-friendly choice.
• Cost-Effectiveness: Nylon is generally less expensive than other materials, making it a cost-effective option for dock lines.

Polypropylene Dock Lines:

While polypropylene is commonly used for waterskiing and rafts, it is not the best choice for dock lines due to several drawbacks. Here are some key considerations:

• UV Degradation: Polypropylene suffers from rapid UV degradation, losing strength and durability when exposed to sunlight.
• Low Breaking Strength: It has a relatively low breaking strength compared to nylon or polyester, making it less suitable for securely docking boats.
• Stiffness and Splicing Issues: Polypropylene rope is stiff and slick, making it difficult to hold a splice.
• Quality Concerns: The quality of polypropylene rope can be erratic, and it tends to degrade quickly, affecting its performance as a dock line.

While both materials have their characteristics, nylon emerges as the clear winner for dock lines due to its superior strength, stretch, UV resistance, and ease of handling. Polypropylene, on the other hand, falls short in these critical aspects, making it a less reliable choice for docking your boat. Remember to consider factors like line diameter, length, and weave type (three-strand, braided, or double-braided) when selecting the most suitable nylon dock lines for your vessel.

Dock line lengths: how to measure

Dock lines are essential for keeping your boat secure and protected while stationary. The right length for your dock lines depends on your boat's length and the conditions in which you'll be docking.

As a rule of thumb, the diameter of your dock line should be one-eighth of an inch for every 9 feet of boat length. For example, a 20-foot boat should use a 3/8" line, while a 40-foot boat should use a 5/8" line.

When it comes to length, the guidelines vary slightly depending on the type of line:

• Bow and stern lines should be about two-thirds of the boat's length.
• Spring lines should equal the entire length of the boat.
• Breast lines, which are used to pull the boat closer to the dock when boarding, do not need to be as long as they are not used to secure the boat.

It's important to have dock lines of the correct length to ensure your boat is secure and to prevent damage caused by sudden movements due to wind, waves, or passing boats. Too-short lines may snap under strain, especially in rough weather or high tidal conditions, while too-long lines can be cumbersome and heavy.

In addition to the above guidelines, consider the following when determining the appropriate length for your dock lines:

• Docking environment: If docking in calm, protected waters, you may opt for slightly smaller lines as they will be under less strain. In open waters or areas with significant tidal shifts, choose lines on the larger side of the recommended range to handle the increased stress.
• Number of lines: Ideally, you should have at least two bow/stern lines and two spring lines on board.
• Cleat size: The cleats on your boat are designed to work with appropriately-sized lines. Ensure that your lines are not too thick to cause problems with tying.

By choosing the right dock line length and diameter, you can ensure your boat's security and safety during your voyage.

Dock line maintenance: washing and replacing

Dock lines are an essential piece of boating equipment, often overlooked, but they require regular maintenance to ensure they remain in good condition. Dock line maintenance involves regular washing and, eventually, replacing.

Washing Dock Lines

Washing your dock lines is a simple process that can be done every few months to prevent the build-up of dirt and grime. It is recommended to use a brush and hose to scrub the lines, but for a deeper clean, you can also use a washing machine. When using a washing machine, always place the dock lines inside a pillowcase to prevent damage to the machine. Set the machine to a gentle cycle with hot water and a normal dose of detergent. If you have white dock lines, you can add some bleach to brighten them. It is also recommended to use fabric softener to keep the lines soft.

It is important to note that washing new ropes is not recommended, as it can damage the protective coating that lubricates and protects the ropes from UV radiation, abrasion, and water absorption. For new ropes, a light scrub with a brush should suffice.

Replacing Dock Lines

Even with proper care and maintenance, dock lines will eventually need to be replaced. Over time, they will become stiff due to repeated dampness and drying. Additionally, factors such as sun exposure, wind, tide, and current can cause line chafe, which is one of the biggest enemies of boat ownership. Line chafe occurs when lines are repeatedly scraped and rubbed against surrounding surfaces, leading to deterioration and weakening of the fibres.

To prevent line chafe, you can use chafe guards, which are protective sleeves placed around the lines to reduce friction. These can be purchased or homemade, using materials like garden hoses, leather, or old jeans.

However, despite your best efforts, there will come a time when you need to replace your dock lines. On average, boaters choose to replace their lines every 2-3 years. To know when it's time, regularly inspect your dock lines for any signs of fraying, fuzziness, or weakness. Test each line by pulling on both ends to ensure they are still sturdy and resilient.

Dock line knots: cleat hitch and clove hitch

Docking a boat is an important skill for any boater. Dock lines, also known as mooring lines, provide a vital connection for boats to land. The appropriate type, length, and number of dock lines are essential for a safe and efficient docking.

The two main types of dock lines are transient and permanent. Transient lines remain on the boat, while permanent lines stay at the dock. Transient lines have an open end that is placed over the dock cleat, and a bitter end adjusted in the boat. Permanent lines, on the other hand, are cut to length and don't require adjustment.

When securing a boat to a dock, four lines are typically used: two spring lines, a bow line, and a stern line. Spring lines are designed to prevent the boat from moving fore and aft, while bow and stern lines keep the boat from moving side to side.

Now, let's discuss the two essential knots for dock lines: the cleat hitch and the clove hitch.

Cleat Hitch

The cleat hitch is a widely used knot for securing watercraft to docks, floating docks, or boat lifts. It is designed to be easy to tie and untie, providing superior strength to hold boats securely. The following steps outline the process of tying a cleat hitch:

• Wrap the line once around the base of the cleat.
• Bring the line over the top of the cleat.
• Wrap the line around the opposite side of the cleat and bring it over the top again.
• Form a figure-eight pattern by wrapping the line under the first arm and then over and around the cleat.
• Create an underhand loop and slip it over the first arm. This secures the free end under the last wrap.
• Pull the free end of the rope tight to secure the cleat hitch firmly.

Clove Hitch

The clove hitch is a versatile knot used for various applications, but it is primarily employed for temporary mooring to dock posts. It is easy to tie and untie, making it an excellent choice for binding. However, caution must be exercised when using the clove hitch as it can slip if there is no constant pressure on the line or if the object it is attached to rotates. Here's how to tie a clove hitch:

• Wrap the free end of the line around the post or object.
• Cross the line over itself.
• Wrap the free end around the post again.
• Slip the free end under the last wrap.
• Pull the knot tight by pulling on both the free and standing ends of the line.

In conclusion, both the cleat hitch and the clove hitch are essential knots for boaters to master. They provide security and ease of use when docking a boat, ensuring a safe and enjoyable boating experience.

Frequently asked questions