turn up

To turn up a line means to wrap it around a cleat, bollard, or pin in order to secure it under load. The line is brought back along itself and wound around the fitting, with the wraps creating friction and preventing the line from slipping. This is the standard method for securing dock lines, mooring lines, and other ropes under tension on vessels and at wharves.

The mechanics are straightforward but require proper technique. A line is first brought around the cleat or pin, then turned back across itself in a figure-eight or spiral pattern, with each successive turn overlapping the previous one. For critical applications like mooring off, the line may be turned up with four or five full wraps to build sufficient grip. The load on the line creates pressure between the wraps, which prevents slipping through friction alone, without any knot at the end.

Variants and equipment

The hardware used varies by application. A cleat is the most common fitting, typically made of cast iron or aluminum with two horns. A bitts or post serves the same purpose on larger vessels. On a pin (a removable or fixed peg), the line is simply wrapped around it repeatedly. The diameter of the line and the size of the fitting must be proportionate; a small line on a large cleat will not develop enough friction, while an oversized line will be difficult to handle and may slip.

Turning up differs from belaying by eye or using a cleating knot. A turned-up line can be released quickly by unwrapping it in reverse, which is essential in emergencies or when the vessel needs to get underway. A knotted line, by contrast, may jam under load and is slower to free. This makes the turn-up method preferred in active port operations and shipboard mooring work.

Common failure modes include insufficient wraps for the load (causing slippage), damage to the line from chafe against a rough or sharp-edged cleat, and loss of grip if the line becomes wet and muddy. Synthetic lines (polypropylene or nylon) turn up readily, though nylon's elasticity can cause creep under sustained load. Natural fiber rope (manila, sisal) holds its grip better but deteriorates faster if left wet.