Clamps & cleats

Cleats (e.g., cam/clam cleats) hold lines quickly and directly—ideal for dinghies, trim lines, and frequent re-cleating. Stoppers/clutches are designed for higher loads (e.g., halyards) and allow for holding/releasing even under tension, often in combination with winches. Cleats are used for securely securing mooring lines, spring lines, and fender lines—so they’re more for “securing” than “trimming.”

Focus primarily on the working load and the rope diameter—not just the breaking load. On a sailing yacht, halyards and stretch lines are subjected to significantly higher loads than, for example, fender lines. Rule of thumb: go one size larger if the line is under high continuous load or needs to be operated in strong winds. Also make sure that the cleat actually covers the specified rope diameter range (e.g., 6–10 mm).

Sheets/trims: Cam cleats or cleats with a guide bar if frequently released/clamped. Halyards: Stopper/clutch systems are common, often in front of a winch. Reefing lines: Cleats or clutches depending on the system; smooth running without chafing is important. Stretchers/fine-tuning: Clamps with good grip, possibly with a pulley system. The load is decisive, as well as whether you need to open them under load.

Stainless steel is very robust and corrosion-resistant, but heavier. Aluminum (anodized) saves weight and is frequently used in high-quality deck fittings, but requires attention regarding galvanic couplings. Composite is lightweight and corrosion-resistant, often ideal for dinghies, sport boats, or as an insulating component. When using a mix of materials (e.g., aluminum fittings on stainless steel screws), insulating layers and suitable sealants help prevent contact corrosion.

Cleats are selected based on the mooring line diameter, boat length, and the expected directions of pull. It is important to ensure a straight line path without sharp edges and sufficient clearance from rail supports, cleats, and the bulwark. For sailing yachts, solid cleats with a good bearing surface and sufficient “horn length” are standard; in tight spaces, retractable cleats may be useful. Below deck, a sufficient backing plate should always be provided for load distribution.

The substrate must be stable; screws must not be driving “into empty space.” For sandwich decks: Seal or fill the core material around the hole as needed to prevent moisture from penetrating. Use suitable sealant, stainless steel fasteners, and backing plates for load distribution. After installation: Check the fit, inspect after the first load, and retighten if necessary.

Ensure a clean line angle to the cleat/clutch, appropriate guide eyes, and sufficient edge radii. Avoid “sawing motions” caused by incorrect line routing. For cleats, use correctly sized lines, ensure clean splicing (backstrakes and cross-strakes), and use protective sleeves where necessary on heavily loaded areas. In areas with heavy vibration, self-locking nuts and suitable washers can reduce rattling.

Check screws/nuts, washers, and backing plates for tightness and corrosion. For clamps and clutches: Check clamping jaws/linings for wear, springs/mechanism for smooth operation, and lines for abrasion. Replace worn clamping jaws or linings in a timely manner—this protects the rigging and increases safety.