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April 2006                                                                                                                                                                  Editor:  Tom Gillard

7-Apr-06

Please remember, in your thoughts and prayers, all our Troops around the world and those on the way home.

***ATTENTION MEMBERS***
Our Club Officers are:

                        Commodore        Vice-Commodore       Harbormaster               Port Captain         Secretary           Treasurer
                          Lucian Cayce      Andy Myrick           Harry Bloodsworth      John Garibotte          Theresa Higgins      Debbi Merrill
                                                                                               Larry Thomas
 

                                                                                                   Spring Clean-up  4-1
                                                                                                       Spring Regatta: May 20-21
                                                                                                       Independence Day: Tuesday (7-4)
                                                                                                       Fall Regatta: Sept 16-17

I hear that there will be a professional tree contractor out at the site on Saturday (1-April) planting full size trees in the cut area.  They will be placing many of the trees in locations that will be conducive to hammock hanging.  If you wish to get a couple of trees placed for your hammock, let them know where you would like to hang out and they will take care of it.  There will also be some professional beach combers out that day.  Don't let them part the beach on the wrong side.

See you soon,

Tom

Knots are used by many people everyday, and sailors should have a basic knowledge of some of the most popular ones.
Here are two that you can practice this month.

It is not as difficult as you might think. Virtually all modern marine sealants fall into one of just three types, each with specific characteristics that make it the best choice for some jobs and unsuitable for others. Selecting the right sealant is essentially a matter of identifying the materials you are wanting to seal--specifically if any component is plastic--and of determining the likelihood of ever needing to separate these components.
If neither component is plastic and if you want to preserve your ability to disassemble the joint, use polysulfide.
Polysulfide is the most versatile of marine sealants. It is a synthetic rubber with excellent adhesive characteristics, and you can use it for almost everything. As a bedding compound it allows for movements associated with stress and temperature change, yet maintains the integrity of the seal by gripping tenaciously to both surfaces. It is also an excellent caulking compound since it can be sanded after it cures and it takes paint well.

However, the solvents in polysulfide sealant attack some plastics, causing them to harden and split. Specifically, you must not use polysulfide to bed plastic windshields or plastic portlights--either acrylic (Plexiglas) or polycarbonate (Lexan). Don't use it to bed plastic deck fittings either, including plastic portlight frames. Plastic marine fittings are typically ABS or PVC, and polysulfide will attack both. If you know that the plastic fitting is made of epoxy, nylon, or Delrin, you can safely bed it with polysulfide. Below-the waterline through-hull fittings are in this group, but when there is any doubt, select an alternative sealant.

Polysulfide adheres well to teak (a special primer improves adhesion), and is unaffected by harsh teak cleaners, making it the best choice for bedding teak rails and trim. The black caulking between the planks of a teak deck is invariably polysulfide. For this application, a two-part polysulfide gives the best results.  Polysulfide is the slowest curing of the three sealant types, often taking a week or more to reach full cure. Because it will adhere to almost anything, polysulfide has a maddening propensity to get on everything, so neatness is called for in using this sealant. Polysulfide sealants will have polysulfide printed on the package, or sometimes Thiokol--the trademark for the polymer that is the main ingredient of all polysulfide sealants regardless of manufacturer.  If you want the two components to be joined together permanently, use polyurethane.  Think of polyurethane as an adhesive rather than a sealant. Its grip is so tenacious that its bond should be thought of as permanent. If there seems to be any likelihood that you will need to separate the two parts later, do not use polyurethane to seal them.

Polyurethane is the best sealant for the hull-to-deck joint. It is also a good choice for through-hull fittings and for rubrails and toerails, but not if rails are raw teak because some teak cleaners soften it. Like polysulfide, polyurethane should not be used on most plastics--acrylic, polycarbonate, PVC, or ABS.
The cure time for polyurethane is generally shorter than polysulfide, but still may be up to a week. For bedding plastic components or where insulation is desirable, silicone is the default choice. Calling silicone a sealant is something of a misrepresentation. It is more accurate to characterize it as a gasket material. If you accept silicone's adhesive abilities as temporary, you will find it is the best product for a number of sealing requirements. It is the only one of the marine sealant trio than can be safely used to bed plastic. It is an excellent insulator between dissimilar metals--use it when mounting stainless hardware to an aluminum spar. It is the perfect gasket material between components that must be periodically dismantled--beneath hatch slides, for example.

Silicone retains its resilience for decades and is unaffected by most chemicals, but it should not be used below the waterline. Because it depends upon mechanical compression to maintain its seal, silicone is not a good choice for sealing hardware on a cored deck. Exposed silicone is a magnet for dirt and repels paint, so never fillet with silicone, and don't use it on any surface you plan to paint. Silicone sealants typically set in a few minutes and reach full cure in less than a day.
For an adhesive seal of plastic components, select a silicone/polyurethane hybrid. An adhesive sealant maintains its seal even when stresses pull or pry the bedded components apart. The sealant stretches like the bellows joining the two sides of an accordion. This accordion effect can be especially useful for plastic portlight installations where the portlights are captured between an inner and outer frame. Although silicone has amazing elasticity, its lack of adhesion means any expansion of the space between the frames is likely to cause the seal to fail.

Either polysulfide or polyurethane would provide a more dependable seal, but polysulfide is certain to attack the plastic, and polyurethane prohibits any future disassembly. The answer to this dilemma is a hybrid sealant--part silicone and part polyurethane. Marketed by BoatLife as Life Seal, this mixture promises a longer-lasting seal for portlights and other plastic fittings where compression of the sealant cannot be assured.

For more information about sealing and bedding, consult Sailboat Hull & Deck Repair by Don Casey.

Every boat owner should inspect the rig of his or her boat once a year. But between these annual surveys, however, the many components of a mast, boom, standing and running rigging should be given a quick check. If this sounds like just another burden to the boat owner, don't despair. Two sailors should be able to complete a rig and deck inspection on an average sloop in an hour or two. And I'd suggest the best time to perform this quick rig check is in mid-season or just before a major cruise.

Half this check consists of an overview of things on deck while the other half involves a trip aloft in the bosun's chair. And just as a precaution, inspect the chair before you or your crew goes aloft and take the time to scrutinize the halyards you'll be using and then review your safety procedures.
 

• Here are things to look for that might cause problems in the rig:

All cordage (that's anything made of line) should be free of snags, knots, and chafed spots. Especially critical are furling and reefing lines, and sheets and halyards. Examine the joints around shackles and wire-to-rope splices if you have those. Wire with broken strands—what sailors call meathooks—should be replaced. And don't neglect seldom-used lines such as the outhaul. If you overlook these areas, it's almost certain that they'll call your attention later at a most inopportune moment.

Broken, bent or balky shackles need to be serviced or replaced. My recommendation is that you also take the time to clead them with a rag and a small amount of metal polish while you're conducting your inspection.

All blocks should turn freely without issuing any noises that indicate undue friction. Take special care to look for checked or cracked plastic sheaves.

Winches should turn easily with a light, even clicking sound.

Even before you go aloft you should stand at a distance off the bow of the boat and note the alignment of the spreaders. On standard rigs, the spreaders are intentionally cocked upwards. If the spreaders on your vessel are drooping or unevenly aligned, you'll need to determine why this is and then correct it. That's good information to have before you go aloft.

At the base of the mast, the sail track on most boats should appear straight and true from aft and both sides. Twists or bends indicate improper tuning.

Bubbles in spar paint or crumbly white aluminum pitting around fittings indicate corrosion forming from trapped moisture or dissimilar metals. Especially critical in this regard is the gooseneck, particularly if there are any winches, cleats, and other fittings are mounted nearby.

The maststep and deck collar should be dry. These areas can degenerate rapidly if water stands inside the mast, so clear the drain hole with wire or a pipe cleaner and seal the area if possible so that it won't collect standing water.

Furling gear should display no undue resistance or emit unusual sounds when turned. Furling line blocks leading aft should offer minimal friction. Flush any hesitant ball bearing blocks with lots of freshwater, and lubricate with an appropriate spray (Harken recommends McLube's Sailkote, and Profurl says its gear doesn't need lubricating because the bearings are "permanently housed in a grease protected by special double lip seals" that ensure water tightness).

Shrouds and stays ought to be free of deep rust pits or broken strands. Look carefully as a broken strand will often lie in place and be difficult to discern right away. Light discoloration that wipes off with your polish rag is of no concern.

Wire terminations, especially swages, should display no unusual rust, swelling, or cracks. Since broken or compromised swages cause most rig failures, use your rag and metal cleaner to get a close look. Bad terminals can be replaced in a few minutes if the proper tools and fittings are on board.
 

Any covers kept on turnbuckles should be easily removed. Use two wrenches to turn each turnbuckle a wee bit, just to ensure that this is possible without too much effort. Bent or frozen parts should be condemned and replaced. And check that all clevis pins are free of corrosion and are the proper size as undersized pins tend to cause accelerated wear.

Damaged or missing cotter pins should be replaced. Tape them to prevent catching unsuspecting sails or skin, but make sure don't tape them in such a way as to trap water. Self-amalgamating tape is a nice touch, but beware of leather as it holds moisture against the metal.

Any lifelines with rust-stained vinyl coating are a clear safety warning. Check the lifeline swage fittings, turnbuckles, shackles, and pelican hooks. Remember that where lifeline wire passes through stanchions is a common spot for wear and tear.

Now, after you've done all that, it's time to go aloft. I find that it's easiest to go all the way up first and then work your way down slowly. You should also check the sail track or groove as you go up. It should be clean and free of rough spots for its entire length. And while you're up there, you'll want to test that the mast-mounted anchor, steaming, foredeck, and spreader lights shine brightly.

Other than the halyard you are using for the bosun's chair, check the operation of the other sheaves for wear and noise. The upper halyard swivel of most furling systems should measure mere inches from halyard shackle to masthead sheave. Alternatively, a halyard diverter should be installed. Failure to observe this can lead to a halyard wrap, and that can break the headstay and ruin your day.

A couple of other things to inspect while you're at the masthead are the wind indicator, the VHF antenna, and other instruments that are mounted atop the mast. The wires from all of these should be protected by rubber grommets where they pass into the mast.

As you work your way down, inspect the shroud tangs, tang bolts, and all wire terminations. These should be more sound than those you looked at on the deck. Again, check that swage fittings, clevis and cotter pins are intact.

Now, few sailors realize how crucial spreader function is to the integrity of the rig. Start by sighting down the spreaders to ensure that they have no bends. Bolts, pins and welds at the inboard spreader roots should not display enlargement or cracks radiating from their base holes. Shrouds passing over the outboard spreader ends must be positively locked in place with seizing wire, bolts or some other mechanical method. If you have discontinuous rigging, check to make sure that the terminals are seated properly. If you find fittings that have had tape on them for some time, check carefully under the tape to ensure that all is well and then retape them.

After that you can head back down to the deck. Once the bosun's chair is stowed, you should be ready to set sail with renewed confidence in the rig.

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