SABOT
Standardized Auxiliary Boat Operations Training
Ninth District - Eastern Region
COMO. Lew Wargo, Sr. DSO-OP/CQEC 03 APR 2015 MARLINESPIKE SABOT
Marlinspike TYPES of LINE
A. Typed by Material: Natural Synthetic B. Typed by Construction: Braided Twisted TYPES of LINE
• Twisted tends to be less expensive than braided. • Braided is smoother to handle • Both have equal strength TYPES of LINE
Cotton: – Natural fiber – Weak – Low cost – Only good for heaving lines and decoration TYPES of LINE
Sisal: • Natural fiber • Inexpensive • Coarse • Susceptible to rot (not commonly used) TYPES of LINE Manila: • Natural fiber • Strongest of natural fibers • Standard for comparison of most lines • Susceptible to rot (should be replaced yearly) TYPES of LINE Nylon: • Most near all-purpose synthetic line • Costly • High stretch (ability to absorb shock) • 3 times strength of similar sized manila • Resistant to sunlight • Does not weaken with mildew • Easy to work TYPES of LINE Dacron: • Synthetic material • Slightly weaker than nylon (about 80%) • Very little stretch • Less Resistant to sunlight than nylon • Wears well (chafe and abrasion resistant) • Costly TYPES of LINE
Polyethylene: • Synthetic material • Used in smaller sizes (ski tow ropes) • Floats • About 1 ½ the strength of manila • Holds up well to the environment (sun, etc.) • Low cost TYPES of LINE
Polypropylene: • Synthetic material that comes in many colors • Floats and is much less costly than nylon • Wear resistant but slippery • Becomes stiff with age, use and sunlight • Looses strength when stretched • Fuses (melts) under heavy loads • Lower cost NOTE: If used for towline, record length and check after use for stretch (weakening) TYPES of LINE
Polyester: Wears well and resistant to chaffing and sun Floats Very low stretch (makes a poor towline) LINE COMPARISON
BREAKING TYPE SIZE STRENGTH Nylon 5/8” 9,000 Polypropylene 5/8” 5,040 Dacron 5/8” 7,200 Nylon 7/8” 17,015 Polypropylene 7/8” 9,528 Dacron 7/8” 13,612 LINE COMPARISON
POLY- FACTOR MANILA DACRON PROP NYLON
Stretch 1X 1.2X 1.3X 3X
Durability 1X 4.2X 5X 4.5X TOWLINE
Select for strength, cost & shock absorbing Inspect regularly Store for easy and quick use. Store w/bridle if bridle is used in rig Eye should be spliced in the end Store w/pendant if used BRIDLES
• Used on some tows and many towboats • Used to center tow • Should be same strength as towline • If hardware is used, hardware should be stronger than the line • Have different sizes PENDANTS
• Short length of towline used to prevent wear on long towline
• Could be 1/2 of a bridle
ANCHOR LINE
• Dedicated for anchoring • Pre-connected & ready for quick use utilizing a swivel, shackle (that is moused) and chain. • Strong enough to hold vessel • Ability to absorb shock • Long enough to give scope of 7:1 or 10:1 • Have a second line DOCK LINES
• Dedicated for docking use. (If you leave lines on your dock have another set for use in other locations.) • Strong enough to hold your boat (Double-up at times) • Ability to absorb shock loads DOCK LINE RECOMMENDATIONS Size of Line to Use on Your Boat For designated dock lines, the size of your line is determined by its diameter and depends on the size and weight of your boat. The following is an approximate guide and is only a recommendation: Recommended Line Diameter Boats under 20 feet = 3/8" Boats 20 to 30 feet = 1/2" Boats 30 to 40 feet = 5/8" Boats 40 to 60 feet = 3/4" Boats over 60 feet = 1" ALONGSIDE TOW LINES • Dedicated use • Sets of 4 lines • Different sizes (Have a smaller size for towing small boats) • Should be approximately as long as the facility “Now Hear This!”
✓ The only type of synthetic line authorized by the Coast Guard for towing is double- braided nylon. Any other lines listed are strictly for comparison purposes.
✓ The Auxiliary may use three-strand nylon for towing.
✓ The rule of thumb is no Auxiliary towing line may be less than 3/8” in diameter. MAINTENANCE
• Keep clean and inspect regularly (Clean dirt from lines as dirt wears lines) • Use the proper size and type for the job • Whip or taps ends to keep from unraveling STORING LINES
• Store ready for quick use • Free of tangles and easy to pay out • Coiled (Discuss how to coil) • Dedicated for specific use (anchor, tow, docking, Alongside towing, etc.) STORING LINES
Lines should be kept clean, coiled and ready for quick use Faking a line for quick use and without fouling PARTS OF A LINE
Working End KNOTS & HITCHES
Bowline: used to make a temporary loop Clove Hitch: Used to attach line around Objects Double Sheet Bend: Used to connect two lines. (Single sheet bend is difficult to undo if loaded) KNOTS & HITCHES
Round Turn w/two Half Hitches: Used to attach line to an object.
Cleat Hitch: Used to attach line to a cleat. (Use 3 figure 8s) (NEVER use w/weather hitch).
Weather Hitch: Locking half hitches used on a flag pole or jack staff (Never on a boat cleat). SPLICES
• Much stronger than knots or hitches • Permanent connection • 3 Strand line is much easier and quicker to splice with practice. ROPE CONSTRUCTION
Laid rope
Webbing
Reprinted with permission from Knots, Slices and Line Handling: A 32 Captain’s Quick Guide by Charlie Wing STOPPER KNOT DOUBLE SHEET BEND or BECKET BEND • Bend • Ties one line to another CLOVE HITCH
• Clove Hitch • Will slip if not under tension • Finish with Half Hitch TWO HALF HITCHES
• Hitch • line attached to object ANCHOR BEND
Secure way of attaching line to an object (anchor) BOWLINE
• Forms a temporary loop SECURING LINES SECURING LINES
Cleats are used to secure lines
Weather Hitch Blocks Do Not Use DIPPING THE EYE
Second line (white) passes under first line (black) and then over the post https://www.netknots.com/ ADDITIONAL MARLINSPIKE INFORMATION
ESTIMATING BREAKING STRENGTH OF 3” SYNTHETIC LINE TYPICAL SHACKLE (“CLEVICE”) TYPICAL EYE HOIST HOOK
WORKING LOAD LIMIT WLL = 3 TONS DECK CLEAT INFORMATION Properly Sized Line for Deck Cleat Present: • Cleats are sized by length.
• Rule of Thumb: The line should be 1/16” in diameter for each INCH of Cleat Length.
• 3/8” line = 6” cleat.
• ½” line = 8” Cleat.
On Auxiliary Operational Facilities: Rule of Thumb: No tow should be attempted using less than a 3/8” line, so a 6” Cleat is minimum.
Backup Plates for Mounting Cleats: • All deck hardware used for towing should have backup plates to distribute the load over a wider area and reduce chance of bolts for pulling through the deck. • The backup plate should be made of pressure treated hardwood or exterior grade plywood at least TWICE as thick as the largest bolt diameter holding the cleat to the deck (NOT screws). • A flat washer and lock washer should be used with the installation with the flat washer at least 3 times the diameter. • If metal as used, it should be at least the same diameter of the bolts and NOT made of aluminum. DECK CLEAT SHOWN IN CROSS SECTION
DECK