Dock Line Basics

Vessel Operation

D O CK LINE BASICS

M o s t s k i p p e r s u s e d o c k l i n e terminology fairly loose but there is more to the basics than just bow or stern lines. There are several lines that can be secured to the bow and stern and depending on t heir dire c t ion and us e, c an b e called other names. Remember that “forward” and “a ” refer to the direction that a spring line runs from the vessel, and not where it is secured on board. Bow springs are secured at the vessel’s bow area. Forward spring lines lead forward from the boat to the dock and control movement stern ward. A er springs stem a from the vessel, and stop movement ahead. Spring lines are used to prevent movement in a berth, ahead or astern. ey are really useful in controlling the e ects of a real active tidal surge. Spring lines are useful where fenders need to be kept in place against piles.

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BOW AND STERN LINES

ere is only one true bow line. It is secured to the forward cleat and run forward along the dock to prevent the vessel from moving to the stern. e stern line leads from a rear cleat to a piling or cleat on the dock astern of the vessel. is line keeps the boat from moving ahead. For small vessels these are the only lines needed for normal wind and current conditions. If located in a tidal environment, keep slack in the lines.

BREAST LINES

ese lines are attached to the bow and stern that lead to nearly right angles from the center of the vessel to the dock. ey help keep larger vessels from moving away from the dock, or are pulled in to help people board the vessel. Bigger vessels may use bow or quarter breast lines.

SPRING LINES

Most boats use two spring lines although it is possible to have four. ey are called the a er bow spring and forward quarter spring.

=FENDER

1. 1. Bow line 2. A er bow spring 3. Forward quarter spring 4. Stern line

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BOAT MOORING

1. Bow line 2. A er bow spring 3. Forward quarter spring 4. Stern line

Most boats can be secured to a dock using four lines. e a er bow spring is crossed with the forward quarter spring and secured to individual dock cleats or pilings. is ensures longer springs and can be snugged up tighter for more e cient tidal control. Remember, if you only have one piling available, position the vessel so this point is opposite amidships. Run both spring lines to it. ese lines will be shorter but still useful.

Chapter 6

e bow and stern lines should be relatively at a 45 degree angle with the dock. e stern line can be attached to the near-shore quarter cleat, but will work more e ciently to the o shore quarter cleat. e longer line will allow the boat ow with the tide with less time checking the vessel.

DOCK LINE SIZING

Most dock lines today are made of nylon, either of twisted rope or braided core and cover. e most o en used material is nylon because of its stretching abilities absorbing shock loads. It is chafe resistant for extended life and is easier on bare hands. e line’s size varies with the vessel. Normally, a vessel in the 50’ range will use 5/8” diameter nylon lines. Dock lines need to have the strength to hold the vessel and have enough density to resist cha ng. ey shouldn’t b e to o heav y that they lose their sho ck-absorbing capabilities. Use the right size line for the vessel since a line too large for the boat will pull hard against the vessel since it won’t be forced to stretch. If the line is too small for the vessel, there is no margin for wear and chafe when under strain. DISEMBARKING-LEAVING THE DOCK

When debarking from a dock, it is easier to release the line from a cleat or piling, from on board the boat, as soon as you leave the dock. Loop a long line around the cleat or pier and leading both ends on board you can release the line easily. Slip one end around the cleat or pile, the pull it back on board. Release the line without the eye splice, so it will run freely from around the pile without hanging up on the splice.

SECURING LINES

When mooring your boat, make sure the dock lines are secured at both ends. Depending on your situation you may need to loop the eye splice of the dock line around a piling. Sometimes the mooring line will lead down sharply from the piling to the deck cleat. Loop the eye splice around the piling twice to keep it from being pulled up o the pile. Pull the line through the looped eye if the mooring line is too small to go around the piling twice or too small to t over once. If you must drop a line over a piling that already holds another boat’s line, run the eye of the line up through the rst eye from below, then loop it over the pile. is will allow either line to be removed without disturbing the other. If another line is dropped over yours, simply reverse the process. Secure a little slack in the other dock line, then slip your eye up through its loop and over the top of the pile. Your line can be dropped through the other eye.

Note: Never use the swim platform cleats for permanent mooring cleats.