ROPE & CORDAGE

Nylon Rope

High-stretch synthetic with excellent shock absorption — the default for anchor rodes and dock lines.

INSPECT BEFORE LOAD · NEVER EXCEED WLL

Rope, splices and hardware are only as good as their condition. Inspect before every use and retire on evidence.

Nylon Rope — nautical chart line drawing

Specification

Fibre	Polyamide (nylon 6 / 6.6)
Construction	3-strand twist or double braid
Specific gravity	1.14 — sinks
Elongation at 20% MBL	15–25%
Wet strength loss	≈ 10%
UV resistance	Moderate — degrades in sun
Abrasion resistance	Very good
Typical use	Anchor rode, dock line, shock absorption

Technical parameters

Diameter 10 mm	MBL ≈ 2,400 kg
Diameter 12 mm	MBL ≈ 3,600 kg
Diameter 16 mm	MBL ≈ 6,300 kg
Diameter 20 mm	MBL ≈ 9,600 kg
Safe working load	MBL ÷ 5 (static)
Dynamic derate	MBL ÷ 8–12

SelectLoad

Overview

Nylon is a polyamide fibre, most often nylon 6 or nylon 6.6, and it is the most elastic of the common cordage fibres. A three-strand nylon line will stretch roughly 15 to 25 per cent of its length before it reaches a working load, and it recovers most of that stretch when the load comes off. That elasticity is the whole point: it turns a sudden snatch into a slow pull, which is why nylon dominates anchor rodes and dock lines.

The same property is a liability elsewhere. Where a line must not change length — halyards, sheets, any control line where stretch shows up as a slack sail — nylon is the wrong choice and a low-stretch polyester or HMPE line belongs there instead.

Nylon loses a little strength when wet, in the region of ten per cent, and it degrades under sustained ultraviolet exposure. It is also denser than water, so a nylon line sinks rather than floats, which matters for rescue work and for anything that has to stay clear of a propeller.

Safety notes

Elastic energy is stored energy. A parted nylon line whips back hard enough to kill — never stand in line with a loaded rope.
Wet nylon loses about ten per cent of its dry strength. Rate the line on its wet figure, not its catalogue figure.
Inspect for glazing and hard spots after any shock load; a line that has taken a serious snatch should be retired, not re-rated.

Using it well

Pre-stretch a new anchor rode once in calm water so the lay settles before you rely on it.
Use a chain leader at the anchor end — nylon has poor resistance to chafe against rock and coral.
Coil with the lay, not against it, and a three-strand nylon line will store without kinking.

Suited to

Anchor rodeDock lineShock absorptionTowing (with care)

Typical applications

SailingAnchoringRescueDock work

Figures are typical catalogue values for new equipment, quoted for comparison and planning. They are not a guarantee for any specific product or any specific load. Always work to the manufacturer’s stated working load limit and to the regulations that apply where you sail.

Related tools

Shock Cord

Elastic bungee cord for holding, tensioning and absorbing small movements — never for load-bearing duty.

Rope & Cordage Select

Anchor Rode

Chain and nylon combined — the chain holds the anchor down, the rope absorbs the snatch.

Sailing & Lines Select

Dock Line

The line that holds a boat to the shore — nylon, spliced eyes, and sized for the worst surge.

Sailing & Lines Select

Safety Harness

A body-holding harness and tether system — the one item on this site that must be certified and inspected.

Safety & Maintenance Select

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