Tying It All Together: A Complete Guide to Choosing Boat Rope

In your boating life, you’ll use lots of ropes. That is because, in the boating world, sail ropes have several different roles to play, including docking, anchoring, sailing, and towing. 

When you start shopping for boat rope, you’ll find that the options are almost endless. How do you know which ones to get? A good starting point is to become familiar with the different types available, understand their pros and cons, and learn their different applications. This will help you figure out which ones will work best for your needs. 

Types of Boat Ropes

Natural and synthetic materials are the two main types of boat rope available. The most common options for natural fibres are manila, hemp, cotton, and sisal. Although they are all affordable options, they are no longer in demand due to their flimsy construction. Synthetic fibres, such as the following, are prefered:

Nylon

Nylon is a synthetic material with the ability to expand by up to 40% of its original size. It is often used for docking, mooring, and anchoring due to its elastic and great shock load absorption characteristics. Nylon’s capacity to stretch makes it strong enough to withstand wind and waves. Additionally, nylon is resistant to rust, abrasion, chemicals, and mildew.

Nylon’s capacity to stretch is certainly advantageous, but it can occasionally cause issues. For example, nylon should not be used where dimensional stability is required, such as while rigging. Furthermore, when wet, nylon can lose up to 20% of its dry strength. Still, nylon ropes will keep their resilience even when they come into contact with water.

Polyester

This synthetic fibre is well known for its exceptional UV and abrasion resistance. It has a low level of stretch but strong strength. If you’re on a tight budget, I’d suggest you try this out because it’s reasonably priced. The fibres have a gravity of 1.38 and a diameter of about 0.02, therefore they won’t float. It is therefore a fantastic choice if you’re looking for something to use underwater.

If the load is prone to jerking, however, stay away from polyester. As opposed to nylon, the stiff fibres are less forgiving and could break under heavy strain.

Polypropylene

Polypropylene could be a great option if you want a fabric with greater flexibility than polyester. It is durable, adaptable, and cost-effective. Because polypropylene floats due to its lighter gravity than water, is a common material used for watersports like waterskiing, tubing, and wakeboarding.

Be aware, nevertheless, that it is not the strongest material on the market. For safety ropes, especially in high-stress applications, I do not advise using this kind. Find one that is UV-resistant because it also becomes brittle when exposed to the sun for an extended period.

Dyneema

This is a modern synthetic fibre used in ropes for boats. Of all the materials listed, it is also the strongest. It floats and stretches only a bit. The pricing is the only downside. Despite its high price, Dyneema is an incredible strength material, meaning it may be used in heavy-duty applications.

Construction

The construction method will vary according to the material. The difference is generally in how the rope is twisted or braided, and this can highly impact the durability. 

• Single-Braided: This rope is braided in a single direction using eight to twelve strands. These strands alternate between going clockwise and anticlockwise. I do not recommend using this type for marine situations because it is not as sturdy as the other types. 
• Double-Braided:  Also known as braid on braid, is the norm for maritime ropes. The braided core is encased in a braided sheath. It is incredibly strong since it has an inner and outer core.
• Three-Strand Twist: Its three strands are twisted to create a sturdy core. It is often used for rigging, anchoring, mooring, and docking. One good thing about this option is that it does not become harder with time.

Diameter

The rope’s diameter is a strong indicator of its size. The diameter determines how strong and heavy it is. Consider selecting something with a greater diameter if you have a large boat. The norm is a 3mm diameter for a 2.5-metre boat.

But larger is not necessarily better when it comes to diameter. You may occasionally need a thinner option, particularly if you need to tie a knot. Larger ropes are harder to knot. 

Length

When it comes to how long boat ropes should be, it will depend on their intended usage. The Water Sports Industry Association advises a minimum of 15 metres and a maximum of 20 metres for towing a tube. The riders’ faces will be doused in water as a shorter tube rope crests the wave. However, a rope longer than 20 metres makes it more challenging to manage the tube’s direction. For anchoring, you’ll need at least 7 metres of length for every metre of anchoring depth. 

Floating Design

There are times when a floating rope is necessary, like when towing a tube. If the rope sinks, there will be splashes on the riders’ faces and a drag on the water. This option is also simpler to collect thanks to its floating construction. However, there are also instances where you require a sinking rope, such as for anchor lines.

Colour 

Many people believe that colour is just significant in terms of aesthetics. But in addition to being visually appealing, colour is crucial for visibility. If you want the rope to be more visible, particularly in murky water or dimly lit areas, choose brighter colours. Additionally, applications for survival and rescue depend on this.

Chafe Guard

This is a crucial component for preventing structural damage to the fibres in mooring and anchoring ropes. It acts as a protective surface, taking the beating from constant friction. The reduced surface abrasion helps improve the longevity of the rope.

UV Resistance

If you want your ropes to last, make sure they feature UV resistance. Over time, excessive heat can cause them to become brittle, which reduces its overall strength.