® seamanship chapter 8 marlinespike. ® slide 2 of 35usps® seamanship learning objectives ...

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Seamanship

Chapter 8

Marlinespike

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Slide 2 of 35USPS® Seamanship

Learning Objectives

Marlinespike seamanship encompasses the art and science of working with rope and line.

With the completion of this material the recreational boater should understand knots, bends, hitches and splices. It also includes the selection and use of line and the proper care of line.

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Definitions

Marlinespike• A pointed tool used in

splicing to open the strands of rope or cable.

Marlinespike Seamanship• General knowledge of

knots, bends, hitches, splices, and care of rope.

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Definitions

Rope• Cordage made of natural or synthetic

fibers, also can be made of steel wire.

Line• Name given rope aboard a boat. Each

line is given a specific name, such as: anchor line, halyard, main sheet, spring line or dock line. A few are still called rope, as in bell rope.

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Definitions

Working Part• Section of line used in forming a

knot

Standing Part• The part of a line that is made fast• The portion of the line not used in

forming a knot• The part of the line around which

the knot may be tied• In use, normally under strain.

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Definitions

Bitter End• Inboard end of a line, chain or cable• The end made fast to the boat

Working End• Attached to an anchor or cleat, etc.

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Bight Standing part Free end Turn Round turn

BightRound Turn

Turn

Free End

Standing Part

DefinitionsDefinitions

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Braided• Diamond braid over a core• Easy on hands• High strength• Slippery

Common laid rope• 3 strands twisted• Tends to kink• Stretches more• Hard on hands• Inexpensive

Choosing A Line

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Rope Strengths

Safe load is 20% of breaking strength Dacron® is the trade name for

polyesterfiber

Breaking Strength of RopeDiameter Manila Nylon Polyesterfiber Polypropylene

Inches Pounds Pounds Pounds Pounds3/8 1350 4000 3800 21501/2 2650 7100 6500 39005/8 4400 11000 10400 60003/4 5400 15000 14400 80001 9000 27000 24000 14400

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Effect of Knots

Strength of Knots and SplicesPrecentage of Original Rope Strength

Figure Eight 45% Overhand Knot 60%Square Knot 45% Half Hitch 65%Sheet Bend 55% Anchor Bend 75%Bowline 60% Short Splice 85%Clove Hitch 60% Eye Splice 90%

Lines are weakened by:• Knots• Splices

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Nylon• Strongest and most elastic• Elasticity absorbs shock• Good for anchoring and

mooring Polyester (Dacron®)

• Minimum of stretch• Good for running rigging

aboard sailboats Polypropylene

• Not as strong as nylon or dacron

• Subject to abrasion, chafe & deterioration from sunlight

• Good point - it floats

Material

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Chafing Gear

Protects line from chafing on chocks and hawse Pipes

Commercially available

Home made using old Water hose

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Start by lacing line over your hand

Form generous loops until line is coiled

Make two turns around coil

Feed working end through coil

1 2 3 4

Coiling a Line

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Tosser• Splits line coil in

half• Tosses line

underhand to the receivers side

Receiver• Holds an arm out

as a target. • Lets line fall over

an out-stretched arm

Heaving a Line

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Basic Knots or Bends

A good knot is easy to tie and easy to untie

Knots or bends weaken line by as much as 50%

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Take a 3/4 turn under the horn away from the load

Lead the free end over and under the opposite horn

Lead the free end over and under the other horn

Tuck the free end under the last turn

Cleat Hitch

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Start by forming an underhand loop

Lead the free end under the standing part

Feed the free end through the loop formed by the underhand loop

Pull the knot tight

Figure Eight

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Good Uses• Furling sails

• Reefing sails

• Lashing small stuff

Should not be used for a varying load

Reef or Square Knot

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Use to join two lines of different diameter• Form a bight in one

line• Lead the free end of

the second line through the bight and around the Standing part of the first line

• Tuck the free end of the second line under the standing part of line two

• Snug up the bend

Sheet Bend

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Form an overhand loop

Feed the free end through the loop

Feed the free end around the standing part

Feed the free end into the loop

Bowline

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Form an underhand loop around the post Lead the free end above the turn Now form another underhand loop around the post Use a half hitch as a “locking knot” to keep the

clove hitch from slipping

Clove Hitch

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Make a round turn around the post or a ring

Lead the free end around the standing part forming an underhand loop

Repeat the last step

Round Turn & Two Half Hitches

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Take a round turn around the anchor ring or a post

Make a turn around the standing part

Feed the free end through the center of the round turn

Make a round turn around the standing part and snug up the bend

Anchor Bend

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Make a round turn around the standing part of a second line or post

Lead the line above the round turn Make a turn around the line

Rolling Hitch

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Whipping• Used to keep the

end of a line from unraveling

Methods• With ‘small stuff’ or

twine• Taping• Liquid whip• Melting nylon line

ends

Common Whipping

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Caring for Lines

Overloading Avoid kinks & sharp

bends Avoid chemicals Protect against chafing Regular cleaning

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Stow carefully Coiling Flemishing

Caring for Lines

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Winch

Start by wrapping the line clockwise Pile the wraps up from the bottom

to the top Make more turns for a heaver load

The correct way to wrap a line around a

winch.

This will not jam.

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Winch

This is the incorrect way to lead a line to a winch.

This will jam.

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Blocks and Tackle

Block• A nautical name for a pulley

Sheave• Roller in a block over which a line

passes as it goes through the block

Tackle• Arrangement of line and blocks used

to provide increased mechanical advantage

Winch• Geared drum turned by a handle and

used to pull lines such as sheets and halyards

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Blocks and Tackles

1:1 2:1 3:1 4:1 5:1

A B C D E

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Making an Eye Splice

Step 2

AB C

bc

a

Step 1

A B C

abc

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Step 4

AB

C

bca


AB C

bc

a

Step 3

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Step 5


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Chapter 8

® seamanship chapter 8 marlinespike. ® slide 2 of 35usps® seamanship learning objectives ...

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