Dock Lines and Fenders: How to Tie Up So the Boat Stays Put

Most damage at the dock happens slowly, over a tide change or an afternoon of wind, and it starts with the way the boat is tied. A few correct lines and well-placed fenders prevent the gelcoat scars, cleat pulls, and piling rubs that show up in every harbor.

The Lines That Matter

A properly secured boat uses more than a bow and a stern line. Bow and stern lines hold the boat fore and aft. Spring lines run at an angle and stop the boat from creeping forward or back as the tide moves. Breast lines pull the boat tight against the dock.

Run at least one bow line, one stern line, and two spring lines. The forward spring goes from a bow cleat back to a dock cleat amidships or aft. The aft spring goes from a stern cleat forward to a dock cleat amidships. Together they lock the boat in place and let it rise and fall without surging.

Size the line for the boat, not the cleat. A line that is too light will chafe through. A line that is too heavy will not stretch and will shock the cleats in a blow. Nylon three-strand is the standard because it stretches under load and absorbs motion.

Leave Slack for the Tide

The most common mistake is tying a boat tight at low tide. When the water rises, a tight line goes bar-tight and pulls the cleat or holds the boat down. When the water falls, that same line goes slack and the boat drifts into the dock.

Set your lines with the boat floating where it will sit at mid-tide, and leave enough slack to cover the full range. Check the tide chart for your basin and confirm the range before you finalize the setup.

Fenders Do the Last Inch

Fenders protect the hull when the boat touches the dock, and placement matters more than size. Put fenders at the widest point of the hull, at the rub rail, and at any spot that lines up with a piling or a dock edge. Double them where the boat is most likely to contact.

Hang fenders low enough to sit between the hull and the dock, not floating up at the rail where they do nothing. Use fender lines, not the built-in eyes alone, so you can adjust height as the tide moves.

Chafe Gear and Routine Checks

Every line that passes through a chock or over a cleat will chafe. Add chafe gear at those points and inspect it each trip. A line that has worn through its cover is a line that is about to part.

Walk your lines before you leave the boat and after every storm. Replace anything frayed, stretched, or glazed. The ten minutes you spend checking lines is the cheapest insurance at the dock.