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DON'S LOG: stories, experience and advice

SECURING FOR A HURRICANE

Hitches, knots, line, chafing gear, cleats on docks, ring bolts, chain, shackles, swivels anchors vs sand screws

When securing lines it is not only a case of securing but also a case of being able to unsecure and re adjust the line.

When securing to a sampson post, bollard, or a winch, Do NOT use a clove hitch. Once a clove hitch is heavily loaded the only way it can be unsecured is with a good sharp knife.

Use a tow boat hitch, to the Americans, lightermans hitch to the English, as this hitch can be unloaded under heavy strain and line veered.

Lines that are on heavy load may have to be moved. Learn to reliably tie a line to the loaded line with a rolling hitch so that the load can be taken on the line secured by a rolling hitch and the loaded line moved to a better tie off point

When securing to a ring bolt, or taking a line around a piling take two turns of the line around the piling or ring then tie a knot. If only a single turn is used thru a ring bolt or around a piling the line will rapidly chafe. When securing, do not use a bowline as once a bowline has been tightened by a heavy load, it is almost impossible to untie. Secure the end of the line back around itself by three half hitches, then mouse the end with electrical tape.

All dock and mooring lines should be three strand nylon, not nylon braid, or the non kink lay, nor high strength no stretch line. Three strand nylon is tremendously elastic and largely eliminates any shock loads on attaching points. Under a heavy load , three strand nylon starts unwinding, getting smaller and will stretch 50 % before it breaks.

Ian Cowan, IWW St Lucia , has an encyclopedic knowledge of line, chain, shackles swivels highly recommends three strand polyrene as it is very UV resistant and resists chafe better than nylon

BUT three strand nylon which stretches has excellent shock adsorbing ability so should be used for spring lines. If there is a surge, no stretch, or low stretch spring lines, create shock loads that tends to remove fittings from boats, cleats and ring bolts from docks.

It has been said that wet nylon is ? % weaker than dry nylon. However I have not been able to find definite reliable answer as to the percentage of loss between wet vs dry nylon.

Knots vs splices, a good splice in three strand line will only weaken the line about 10 %. A knot, depending on which knot is used will weaken the line 20 to 30 % . If two turns are taken around the securing point, the load on the knot securing the line is negligible so no loss of strength.

Big mooring lines to hurricane anchors or sand screws should be spliced , see more on this subject in Laying up on a hurricane mooring.

Chaffing gear, everyone has their own ideas and preferences. In the old days, wrap the line with narrow strip of old canvas spiralled around the line and secure with marline . Today, obtain a piece of clear plastic hose whose inside diameter is the same as the diameter of the line, slide it over the line to where it should be and secure the ends with many layers of duct or gorilla tape. If you can not slide the hose where it is needed split the hose, fit it where needed, the slot up and secure with duct or gorilla tape. I have discovered over the years that duct or gorilla tape works amazingly well as chafing gear on line. Other experiences sailors may have different idea of the best chafing gear that has worked for them. Remember the old seaman's saying "different ships, different long splices".

When securing to docks or floating piers do not rely on cleats and ring bolts as under heavy load they may pull out. On floating piers run lines twice around the piling well above the expected tidal surge. Usually in protected marinas in the eastern Caribbean tidal surge is about 3'. Secure the line back on itself with three half hitches with the end moused with electrical tape.

When securing to piers, as long as the marina is sheltered from wind blown surf, the tidal surge in years gone by, has seldom if ever gone much above 3'. Organize your fenders so that they will bear on the dock even when there is a tidal surge.

Before hurricane season starts buy and have on board extra big fenders. Often in hurricanes fenders get overloaded and explode.

Chain is very variable in strength according to what type of chain it is. In the Caribbean finding out exactly what type of chain you are buying, its SWL safe working load and BS ,breaking strain is hard to ascertain from most marine suppliers in the Caribbean.

However my old friend Ian Cowan, manager of IWW Rodney Bay St Vincent is a walking encyclopedia of what supplies are available in the Caribbean or can be ordered. Ian arrived in the Caribbean, in 1970 was hired by the late Bill Steven of Stevens Yachts, which was one of the pioneers of bare boat chartering, to commission 26 Morgan Out Island 41s for the Moorings and Stevens bare boat fleet. When this job was finished he hire Ian to run Stevens Yachts, a fleet of both bare and crewed boats. The company was bought out a couple of times, names changed but Ian was sold with the company!!!! When Sun Yacht St Lucia was moved to St. Vincen in 1997 , Ian resigned. Ian stay on working indecently sail repair, rigging, gas refills, laundry . In Ian, his wife Rosemary and some stateside partners formed Island Water World St Lucia, iwwsl.ltd@candw.lc.

When ordering chain, shackles, swivels , line I strongly recommend you either sail to St Lucia, consult and order thru him, or contact via e mail consult and order thru Ian at iwwsl.ltd@candw.lc or Julian@islandwaterworld.com

Jolyon.ferron@budgetmarine.com  can also supply chain.

Both IWW and  Budget will sell lengths  of chain cut from the standard long length but will  levy a  surcharge of 20%   as  when they start cutting chain they sometimes end up with an odd length that no one wants.

For good solid information on chain that is in everyday use when anchoring, and how to obtain strength but light weight go to Lynn Pardey's Capable Cruiser pgs 351/8

A discussion of chain, shackles, swivels and riser line will be found in section Hurricane Moorings.

In a very hard blow, tropical storm or hurricane relying on the anchor windlass or capstan to stay in place on a modern yacht is the height of optimism. Carry a number of chain hooks. Put two or more chain hooks on to the chain and attach the chain hooks to strong points. ½"nylon has a breaking strain of 5,000 lbs, which is considerably more than 3/8 chain. Two chain hooks secured to two strong points with ½ nylon will do the job.

Galvanized shackles vary drastically in quality and strength. In CH marine in Skibbereen, and in other divisions of CH marine, or any marine supplier that supplies the commercial marine industry or fishing fleet, there are three types of shackle

The plain galvanized ones SWL not marked on them, strength probably same as the same sized chain.

Ones with yellow pins marked with SWL are superior to the plain shackles because

The best the ones with green pins,  with SWL marked on them and highier strength than the yellow pins. They are  the most expensive because they are made with high strength  steel.

I was amazed when I found a mooring buoy that had drifted ashore in the winter in Glandore harbour West Cork. The chain had broken, but the short mooring pennant was still there with a shackle whose pin had wasted away to about 1/16 of an inch yet I was able to unwind the pin, it did not wring off as the green threaded pin had not frozen to the shackle.

It convinced me that paying the extra price of for the green pinned shackles is worth while.

In the Caribbean Ian says IWW stocks three types of shackles, plain galvanized, ones with white pins. And the best with yellow pins. The yellow and white pinned shackles are stamped with their SWL. The yellow pinned shackles are high strength shackles tested to SWL.Ian advises paying and buying the yellow pin shackles.

CH marine  shackles come  from the dutch company van beest.

The  pin markings  are  the EU standard colors,  IWW buys  from the  states from a  high quality supplier who probably uses the standard US  coloring  of pins.

Do not secure the pins from unwinding with wire. Any wire may set up a galvanic action, use plastic cable ties.

Swivels, there are new stainless swivels on the market that look wonderful but according to letters to editor in Caribbean Compass, some have failed. The reason for failure I can not remember but I have never heard of a failure of the good old fashioned galvanize swivel except those that failed due to old age. Use a big galvanized swivel, inspect yearly and replace as necessary.

However Ian Cowan advises against using swivels as he say he has heard too many stories of disasters caused by swivel failure.

On solution to the twisted chain problem, to un twist twisted chain, periodically go off sounding, veer ALL your chain. Before doing this make sure the bitter end is secured to a strong point by line not a shackle. Securing the bitter end with a shackle is a mistake. If you suddenly discover you must veer all your chain and buoy it, if it is secured by a shackle , you will probably discover the shackle is rusted and frozen in place where as line carn be cut.

Before you veer all your chain in deep wate, check the line pulling power of your windlass. '3/8 chain weighs one pound per foot, 300 ' of chain, plus 50 lb anchor 350 lbs. Friction of chain coming over roller 30%. So total line pull with everything hanging straight down is 450 lbs. Check the rated line pull on you windlass or capstan before hanging anchor off sounding to clear chain.

Anchors, see Surviving Klaus

Anchors vs sand screws for permanent moorings, see Laying up on a hurricane mooring]

Chain sizes, nylon pennant and buoy for permanent mooring see Laying up on a hurricane mooring and consult with Ian Cowan .

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