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SAILING & LINES

Fender Line

Short, adjustable lines that hold fenders at the right height — simple, but they must be right.

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.

Fender Line — nautical chart line drawing

Specification

Typical fibrePolyester or nylon
ConstructionBraided, 3-strand
Diameter range8–10 mm
ElongationNot critical
EndsWhipped or heat-sealed
Common errorLine too short to adjust for tide

Technical parameters

8 mm polyesterMBL ≈ 1,900 kg
10 mm polyesterMBL ≈ 2,900 kg
Typical length2–4 m per fender
KnotClove hitch or rolling hitch
AdjustmentAt the stanchion
Spare lengthCoiled and stowed
SelectMaintain

Overview

A fender line holds a fender against the hull. It is short, lightly loaded and easy to overlook, which is exactly why fenders end up hanging at the wrong height or disappearing over the side. A fender that rides too high protects nothing; one that rides too low can float free of its line and drift away.

The line needs to be adjustable because the freeboard changes: a dock that is high at low water may be low at high water, and a rafted boat changes the geometry again. A clove hitch or a rolling hitch around a stanchion, with the spare length coiled and stowed, gives the adjustment without a permanent fitting.

Eight to ten millimetre line is generally right for a fender: thick enough to grip and to knot reliably, thin enough to pass through a fender's moulded eye. The line should be long enough to allow the fender to be brought inboard when underway and to be adjusted through the full tidal range at your usual berth.

Safety notes

  • Bring fenders inboard before getting underway. A fender on a slack line can swing, catch and be lost or cause damage.
  • Check the line where it passes through the fender's eye — that is where fender lines chafe through.
  • Do not use a shock cord as a fender line where it could stretch and release a fender under load.

Using it well

  • Tie a figure-eight stopper below the fender's eye so the fender cannot slide off the line.
  • Adjust both ends of the boat's fender set together — a fender that is out of line protects nothing.
  • Rinse fender lines in fresh water; salt makes them stiff and hard to knot.

Suited to

FendersDock workRaftingMooring

Typical applications

Dock workMooringRafting
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.

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