A cringle is a term used in sailboat anatomy to describe a small hole in the sail. Cringles are involved in reefing a sail, securing it to the boom, or providing an opening for a boltrope or other rope. The cringle is also frequently reinforced with a grommet, a metal ring that lines the edges of the hole to guard against chafing over time.
Although the term cringle can apply to any hole through which a rope can be passed, it most frequently refers to holes in the sail itself. Most sailboats contain several cringles, which are almost always placed along the leech, or outer edge of the sail. Some rigs will also contain cringles along the foot, or bottom edge of the sail, to attach it securely to the boom or provide extra reefing points. The luff, or forward edge of the sail, will also contain cringles that are designed to support and guide a line known as the downhaul, which tightens the sail along this edge.
The grommet that lines the cringle often provides additional structure to prevent the sail from wearing or stretching. Sailors will often use the two terms synonymously because they both technically contain the rope or line that passes through the hole. Although they are often best for the sail, grommet-reinforced cringles can sometimes create more severe wearing on the ropes, especially if they are used in rigs with higher pressures. Some boats get around this by using a pulley system instead of a traditional cringle setup.
Cringles are most commonly used when reefing a sail, or reducing its surface area to guard against storms, heavy winds, or unexpected gusts. By narrowing the sail’s edges and decreasing its size, the amount of force against the sail also decreases, stabilizing the boat during rougher conditions. To aid with reefing, they are placed slightly inward towards the center of the sail along each edge.
When reefing a sail, sailors will loop ropes through the cringles along the foot of the sale and tug them downward towards the boom. The leech of the sail will often contain cringles with a reefing line, which can be used to pull the back edge of the sail inward. After this, the downhaul can be pulled down through the cringle on the sail’s luff to decrease the sail’s overall height. In this way, they provide a safe and effective way to reduce the surface area of the sail and protect sailboats from capsizing or becoming damaged during heavy winds.
