Some Notes on the Deployment of Dock Lines

By Seaman Bluenose Bluejacket,

a tight-laced tar serving under Stuffy Oldaways

Overview

The effective use of dock lines remains a challenge to countless new and weathered sailors alike. Rigged poorly, they reflect on the qualities of the yacht and can leave her battered and rent asunder. Rigged correctly, they give the yacht a seamanlike appearance and keep the boat secure in a slip in all but the worse weather.

While this article is not necessarily the only way to rig lines, it will hold a boat safely in a slip under most conditions and will pass even the rigorous scrutiny of Stuffy Oldaways, that bastion of nautical tradition.

Definitions

Finger – a small floating pier to which a boat may attach alongside.

Dock – Contrary to popular use, a dock is a space of water, usually surrounded by floating fingers, in which your boat sits. An evening stroll down the docks results either in wet clothes or sainthood, depending on the results.

Bow or stern breast – relatively short lines that run from a bow cleat, usually through a chock, to a cleat or post on the finger.

Chafe gear – An abrasion-resistant sheath or cover designed to wrap around lines at critical points to prevent them from wearing. Chafe gear comes in many styles and in its simplest form can simply be a piece of rubber hose through which the dock line runs.

Fender – A hemp or plastic cushion, usually tubular in construction, designed to provide protection for a boat entering or leaving a slip. They are not designed to protect a boat from chafing against a pier in anything but calm conditions.

Bumper – A metal or similar strip along the front and rear of an automobile designed to protect against light impact. There is no known marine use for a bumper.

Selecting Line

There are a couple of easy guidelines to remember when outfitting with dock lines:

· Bigger is better. Always go a size or two up from whatever the “recommended” size is for your boat. However, don’t go so big that the lines (with chafe gear) will not fit easily in the chocks.

· Stranded is better. Braided dock lines are strong, but have less stretch in them that stranded lines. With dock lines, the ability to stretch is as important as the breaking strength of the line. Any line likely to find herself on the windward side of the boat (under any wind conditions) really should be stranded.

· Longer is better. Dock lines work best when they have plenty of room to give. A short dock line tied from a bow cleat to a finger cleat, spanning only a few feet, is much more likely to break or to damage one or more of the cleats or their bedding. Avoid using short dock lines whenever possible. At least 2 of your dock lines should be as long as the boat.

· More expensive is (often) better. Don’t get the cheap stuff. You’ll be sorry. New England Rope is one of my favorites. For the traditional look without risking arrest under the hemp import laws try brushed Dacron. It will resist rot and UV deterioration but still has that ship-shape appearance.

· Whip the ends. Dock lines with frayed ends will not last long. Various forms of taped ends look shabby and will eventually come loose anyway. Avoid the dread “butane back splice” at all costs.

How many lines to have

The best scenario calls for 4 lines greater than the length of the boat and 4 lines half the length of the boat. This allows for 2 forward stern springs, 2 after bow springs, 2 bow breast and 2 stern breast lines. You can usually get by with fewer, but it’s always good to be prepared. (We’ll discuss each of these types of dock line and their functions and uses later on.) For a 30’ boat I use (4) 35’ spring lines and (4) 15’ breast lines. Eye splices at one end will make life easier, but a bowline will do the trick also.

Basic Line Layout

Perhaps the most common mistake is to tightly lash the boat to the finger, squeezing the fenders (they are NOT bumpers) in between the boat and the finger to hold everything together. While this may work in light wind and ideal conditions, it is definitely not the way to secure your boat. Once the boat and the finger start moving up and down in the waves, the fenders pop out and the dock lines pull the boat into the finger, bashing and scraping your topsides.

The diagram above represents a much better configuration. The boat is held in the middle of the slip, well away from any finger or pier. While fenders are still acceptable, they should never actually touch the finger.

The spring lines, long stranded lines running from a stern cleat to a forward cleat on the finger, and vice-versa, should be rigged securely but not taut. There should be plenty of play in them so as the boat rocks up and down in the slip the spring lines take up the pressure. The bow breast and stern breast lines should also be of stranded line and should be as long as possible, though they will naturally be shorter than the spring lines.

All of your lines should have play in them. When the boat is not moving in the slip they should be slightly slack. When the boat bounces up and down as the result of wind and waves, the windward lines should tighten together. Breast and spring lines should tighten at the same time so that both are working to take up the pressure.

Securing Your Lines – Two Finger Configuration

Most of the time you’ll be securing your boat to floating fingers or piers. The distance between the point of attachment on the boat and the point of attachment on the finger remains constant since the tide lifts both the boat and the finger. If for some reason you are securing to a fixed object like a piling, make sure you allow for sufficient slack to cover the full range of the tide. Failure to do so will lift your boat cleats right out of the deck, leaving a messy hole where the cleat used to be.

When rigging your lines make sure that the lines play fairly from the finger cleat to the cleat on the boat. Check for any potential chafe or pressure points that might damage the line or the boat. A line passing loosely over a coaming does little damage when waters are calm, but as soon as the wind whips up the line becomes a rasp, with predictable results. Likewise a spring line that rests gently against a stanchion when all is calm may extern significant force when pulled taught during a blow. In both cases a little bit of observation and preparation can avert an expensive repair.

Bow breast lines are usually secured to a bow cleat and then passed through a pair of bow chocks. Make sure adequate chafe gear protects the lines as they pass through the chocks. Insufficient use of chafe gear is a significant cause of line failure. Also make sure the chafe gear is secured in place by a small piece of line woven through the strands of the breast line. This will prevent the chafe gear from working itself out of the chock.

If stern breast lines are connected to a pair of stern cleats on either quarter of the boat, you can “extend” the length of the lines by crossing them. In other words, the port cleat is used to secure the starboard breast, and vice-versa. (This method is very common on power boats that back into a slip.)

Sometimes, particularly when using over-sized lines, you’ll find yourself running out of space on the boat’s cleats. It is possible to secure lines to points of attachment other than cleats, but be careful when doing so. A great deal of pressure is exerted on these lines. Lines secured to a stanchion or similar equipment may cause significant damage to the boat. A winch usually serves as a reasonable point of attachment, since winches are designed to take a reasonable amount of load.

Occasionally one is tempted to add cleats that ride along the jib block tracks. While this may seem convenient, tracks are not designed to handle the jerking horizontal pressure that comes from dock lines. Your track may begin to pull up from the deck, allowing water to creep in. Worse, it may be several years before the damage is visible. By then significant portions of the deck may need to be replaced.

If a finger has multiple points of attachment, try to use them all. If a spring line and a breast line are secured to the same cleat on the finger and the cleat fails, both of your lines are now useless.

Securing Your Lines – One Finger Configuration

The one-finger configuration is essentially the same as the two-finger configuration with one less point of attachment. This configuration will work well, especially if the prevailing wind is not from the direction without a finger.

Preparing for a Storm

The best place to be during a storm is on a well-maintained mooring. If you must ride out the tempest in a slip, careful attention to detail will help you make it through safely.

When preparing for a storm, follow the same basic layouts described above, but pay special attention to the windward lines. Most of the time you will be able to identify which lines will become the windward lines by close attention to the forecast. Make sure those lines are the stronger lines and that they are secured to multiple points on the finger in case finger hardware fails. When in doubt, add more lines. It may look a little silly but you will sleep better.

Notes on Cleats and Lines

If used correctly, cleats allow lines to be made fast securely yet also allow them to be released quickly under pressure. When making fast, use a set of half-hitches in the commonly prescribed manner. Use the free end of the line (not the line that goes to the boat) to complete the hitches. This will allow the knot to be rapidly undone even if the line is under extreme pressure.

Use only a set of two half-hitches. There is no need to replicate the Gordian knot. More turns on the cleat will not make the knot any more secure and may seriously impede someone who needs to untie the knot in a hurry.

After lines have been made fast, any left over length should be flaked or laid down in tight concentric coils. Not only does this look good, it will help the line dry quickly. (A loosely flaked line will dry faster than a coiled line and may discolor the deck if left too long, but some concessions to fashion must be observed.)

Notes on Fenders

Fenders serve to protect a boat’s topsides when coming into or leaving a slip. They are not designed for permanent protection from chafing against a finger. When a boat is well secured in a slip the fenders should not touch the pier.

When coming into a slip, fenders should be deployed at the last possible minute. Ideally an observer standing on the shore should never actually see the fenders while the boat is in motion. Sailing down the bay with one’s fenders a-dangle is, according to Queen Hooper Foster, the equivalent of walking about with one’s fly open to the breeze.