Need to replace your mainsail furling line? Here's how to make a new one in under 90 seconds.

Start by cutting the right length of line. Either measure the old one or follow the same route step by step, marking a reference point on deck.

Use a polyester rope with a tight cover—this gives better splicing.

Feed the line through the furling drum, following the original path: through blocks, sheaves, and rope clutches.

Use a messenger line or a splicing needle if access is tight.

⚠️ Note: Pay attention to the furling direction—usually clockwise.

To work properly, the line must be under tension—like a bicycle chain.

Use a block or low-friction ring combined with a shock cord.

Attach the shock cord to a fixed point aligned with your rope clutches.

Tip: To adjust the shock cord tension, make sure the furling line is snug—not too slack, but without excessive tension.

You should still be able to make three full turns around the winch.

Overlap the two ends of the ropes to be joined. Make a mark at 60 cm (A) and 110 cm (B) from the tail.
Uncover each rope up to point B.
Using a splicing needle, insert the core from point A into the core up to point B (i.e. 50 cm), and do the same in reverse.
Tension the whole assembly, then secure the center with a whipping.
Trim any protruding strands, then tuck the covers into each other to smooth out the junctions.

Manually turn the furling drum to check that the line furls and unfurls smoothly.

Also test the travel: the sail should furl fully from start to finish.

Pro tip: inspect and replace your furling line every 4 to 5 years to avoid failure at sea.

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See you soon on the water!