Monthly Archives: November 2010

Quick Tips to Ponder Part 5 – Is It a Good Knot or Not

bowlinesm.jpg (2331 bytes)Knots must earn their worth aboard your boat. In order to be worth their salt they must:

  • Hold fast under all conditions
  • Come apart easily when you want them to

You must do your part with respect to knots. You should be able to tie them as automatically as you do your shoe laces. The reason that you don’t have to think about tying your shoes is something called “muscle memory”. The muscles in your fingers have been flexed in the same manner so often that your brain doesn’t have to send individual signals to all the muscles involved. The memory appears to actually lie in the muscles themselves.

Knots obviously introduce kinks into a line that can diminish its strength. Some knots introduce tighter kinks than others. A three-strand line that has been tied with a knot that causes a tight kink can lose up to 30 percent of its strength. This loss of strength can cause a line to part more quickly under strain.

The reduction of line strength varies with the knot. Some examples follow:

  • Anchor bend: 24 percent
  • Round turn and two half hitches: 30 – 35 percent
  • Timber hitch: 30 – 35 percent
  • Bowline: 40 percent
  • Sheet bend: 45 percent
  • Reef knot: 55 percent

See also: Marlinespike for Recreational Boaters

Leave a comment

Filed under Boat Operation, Boating News, Boating Safety

Quick Tips to Ponder Part 4 – Navigation

Estimating Distance Off

In clear weather, one can distinguish the shapes of tall houses, trees, lighthouses, etc. from about 8 miles offshore. The distance to the horizon however can be quite small. if, in a small boat, your eye is 5 feet above the water level, the distance to the horizon is only 2.5 miles away. Although the distance can be more accurately estimated using the formula

1.17 times the square root of your height of eye = Distance to the horizon in nautical miles

Some rules of thumb you can use are as follows:

  • A light-colored beach can be seen at approximately 4 miles offshore from the deck of a typical small boat.
  • Individual windows in buildings can be distinguished by day or night at about 2 miles off.
  • A large buoy is visible at 2 miles.
  • A small buoy is visible at 1.5 miles but color and shape will not be clear.
  • The shape of a small buoy can be distinguished at about 1 mile.
  • The color of a large buoy can be distinguished at about 1 mile.
  • A person is seen as a moving black dot without limbs at 1 mile.
  • Movement of a person’s legs or arms can be distinguished at about 400 yards.
  • Faces can be seen, but not necessarily recognizable, at 250 to 300 yards.

Pencil Radar

It is possible to use something as simple as a pencil to determine approximate distance off. In order to use pencil radar:

  • Locate an object that can be seen onshore which is shown on your chart with a charted height.
  • Hold a pencil up at arm’s length and site the top of the object with the tip of the pencil with one eye.
  • Switch eyes.
  • You should estimate the horizontal distance (HD) that the tip appears to have jumped relative to the known height of the object. For example, if you are spotting the top of a spire on a mountain (as shown on your chart at 600 feet), when you shift eyes the pencil appears to shift twice the horizontal distance as the height, you would have an estimated horizontal distance of 1200 feet.
  • Now you simply use the formula D (Distance Off in feet) = HD (in feet) X 10. In our example, if the spire was 600 feet and the horizontal distance (HD) is 1200 feet, the distance off the spire = 1200′ X 10 = 12,000′ or 2 approximately miles.

Navigating By Eye

When navigating in areas with uncharted coral reefs it is a good idea to wait until the sun is high and behind you – from 10AM to 4PM. (This is why charter companies encourage you to anchor no later than 4PM.) Height above deck is an advantage to the spotter and vision can be improved with polarized sunglasses. Calm, grey days are the most difficult when trying to look deep into the water. As a rule of thumb in reading the water:

  • Dark blue tones mean deep water, 20 fathoms or more.
  • The blue becomes lighter with decreasing depth, and the turquoise (green-blue) is a warning of shoaling. it is the color of the coral sand covering a flat expanse of reef with 4-6 feet of water coverage.
  • Dark brown indicates coral heads.
  • Brown or yellow indicates reefs with a depth of 3 or 4 feet over them.
  • Green-brown means a grassy bottom.
  • White means very shallow water.

Piloting Using Echoes

As kids we all thought that echoes were fun and interesting but did you know you could use them in piloting? Note the time in seconds from a signal to the return echo from a cliff, iceberg, wharf, or moored freighter. Every second’s delay indicates a distance off of 1 cable, or 200 yards. Every 10 second’s delay indicates a distance off of 1 mile.

This rule could be useful in fog some day. A blank pistol shot produces a sharp echo, but the ship’s bell or horn will work as well. Even a loud hailer works in close quarters. The Rule of Thumb at work here is that sound travels about 1 mile in 5 seconds.

Leave a comment

Filed under Boat Operation, Boating News, Boating Safety

Quick Tips to Ponder Part 3 – Varnish

When to Touch Up Varnish

The look of your brightwork says a lot about the pride of ownership that a boater has for his/her boat. A rule of thumb that you can use to tell if you need a touch up or a major overhaul of your brightwork is as follows:

Use a mild, soapy solution to wash thoroughly and get rid of all the grit and grime that has collected. (Hopefully, you do this more than once a season.) Rinse thoroughly with fresh water and dry. Take a towel and wet it thoroughly (make sure it is dripping). Drag the towel across the varnished surface. If the water that the towel leaves behind beads up the varnish is still in good condition. However, if the water that is left sheets or lies in flat streaks, you should plan on a light sanding and applying a couple of coats.

When A Varnish Touch Up Is Too Little Too Late

The only thing worse than going to the dentist is scraping varnish down to bare wood, sanding smooth and starting the arduous task of rebuilding 8 to 10 coats that will give you that “mirror” finish.

You can only patch the small abrasions and scratches so long until, ultimately, moisture has crept under the varnish and into the wood. This saturation of fresh and salt water will show up as dark patches under the still shiny finish. You will also notice lighter patches as the hot sun has glared down and has started to separate the varnish from the wood because of the moisture or perhaps the impact of dropping something on the varnish. It is at this point that you have no choice but to restore the integrity of the surface of your brightwork by scraping it down and starting anew.

Use the following as a step-by-step process to get brilliant brightwork consistently.

  1. I like to use a heatgun and scraper to remove the old varnish. This seems to go faster than sanding alone. In tight spaces you may have to just use sandpaper and lots of elbow grease. You should practice on a spare or out of sight piece to make sure you can control the scraper. Be careful not to make gouges in the wood.
  2. Once the varnish has been removed, sand the wood smooth using finer and finer grits of sandpaper. You may want to start with 80 grit to get all the rough areas and work up to 400 for that “babies bottom” smoothness.
  3. Before starting to apply varnish, make sure all sanding dust has been removed. Use a tack cloth dampened with a thinner that is recommended for the varnish you have selected. I lean toward varnishes with a high U/V rating. They tend to hold up longer in the sun.
  4. Stop! Don’t shake that varnish can, this is not paint. Shaking or even stirring will introduce bubbles which will show up on your brightwork. Most likely you don’t need to mix the varnish but if you feel obligated to make it move around the can while you watch, just swirl it slowly.
  5. Always filter the varnish by pouring from the can through a fine filter, or nylon stocking, into a small, clean container before applying each coat.
  6. For the first coat, thin the varnish with the compatible thinner 50/50. This will act as a sealer coat. Subsequent coats may be thinned if necessary to provide a good flowing viscosity.
  7. You may use a “real brush” or the disposable throw away foam brushes. Just make sure each is thoroughly clean and, if using a real brush, pull to remove any loose bristles or they will end up in your varnish work.
  8. Let the varnish flow on and only try to cover a small area at a time. Look for brush bristles, bubbles and holidays (spots that you missed) as you proceed.
  9. Make sure that each coat is completely dry before attempting to add another. Lightly sand with 400 grit paper between each coat.
  10. Repeat until you have 8 to 10 coats and that “mirror” finish that will be the envy of all at the marina.

Leave a comment

Filed under Boat Maintenance, Boat Operation, Boating News

Quick Tips to Ponder Part 2 – Maintenance

Hose Guards

Don’t throw away that old hose. Cut a piece about a foot long, split it and put it around your dock lines and anchor lines where they pass through the chocks to prevent chaffing.

Kitty Litter Below

When you put your boat up for a period of time put a few boxes of kitty litter below. It will absorb moisture, reduce mildew, and eliminate odors.

The Handy Coat Hanger

Always have a metal coat hanger in your tool kit. It can be used to:

  • free hose blockages
  • hook something in an inaccessible area
  • used to replace a cotter pin
  • used as a temporary tie down
  • free blocked limber holes

Off-Season Maintenance – Paint

The off-season in many parts of the country can be used to maintain, upgrade or plan for the fun of the upcoming spring and summer boating season. A few “Rules of Thumb” that come to mind may help you with your winter activities.

Need a new coat of paint? In order to estimate how much paint to purchase use the following formulas. (Measurements should be in feet and your answers will be in square feet to cover). You then need to refer to the manufacturer’s brochures or the paint can itself to see how much paint is required to cover the square footage area.

Bottom Paint: Use the Load Waterline Length (LWL) times the beam times the draft.
For full keel boats multiple this figure by .75. For lighter boats with less keel multiply this figure by .50.

Example: LWL = 30  Beam = 10  Draft = 5   30 X 10 X 5 = 1500 X .75 = 1125 sq. feet to cover for a full keel boat.

Decks: Overall length of deck times the beam times .75. (subtract area of cockpit and deck structures)

Example: Deck length = 34  Beam = 10  34 X 10 X .75 = 255 square feet

Topsides: Overall length plus beam time 2 times the average freeboard.

Example: Overall length = 36  Beam = 12  Avg. Freeboard = 5  36 + 12 X 10 = 480 sq. feet.

Leave a comment

Filed under Boat Maintenance, Boat Operation, Boating News, The Boating Environment

Quick Tips to Ponder Part 1 Operating in Fog

Fall brings another challenge to boating and that is operating in fog. Judging how close and a what speed a vessel is approaching can bring challenges.

Objects may seem larger than they appear…

When operating in fog be aware that visibility can drop drastically. When visibility is between 30 and 150 yards objects, including other boats, may appear twice as large as normal. The illusion also tends to make you think that they are approaching at a much faster rate than they actually are.

Steering a straight line without a compass…

Many a small recreational boat owner will find themselves steering in fog without a compass. With no compass and with no reference points because of limited visibility, even the best helmsman will tend to steer in circles.

To steer a straight course, attach a light line high on the bow or from the mast and drag a drogue, cushion, or anything that can create resistance over the stern. Keep the line centered where it passes over the stern and you will steer a straight line.

Actions to take in fog…

If you see a fog bank approaching or fog starting to form be sure to fix your position by any and all means necessary, including electronically or by bearings. If possible, anchor and wait out the fog in an area which is too shallow for large ships to operate. Don’t forget to ring your bell for 5 seconds every minute while at anchor. Post as many lookouts as you have onboard and listen intently for the sounds of other vessels. If you hear a vessel approaching, sound the optional one short – one prolonged – one short blast to notify them of your presence.

Leave a comment

Filed under Boat Operation, Boating News, Boating Safety, The Boating Environment

Don’t Neglect Your Boat During Winter Months

If you leave your boat in-the-water during the winter months. Don’t get into the mindset of “out-of-sight, out-of-mind.” You should visit the boat as often as possible to check on those things that can go wrong when no one is watching.

Bilge Pumps

It is important to frequently test your bilge pumps by switching from the automatic to manual position on the bilge pump switch. However, this doesn’t guarantee that the pump will work when unattended. You should also check the automatic float switch by manually raising it to make sure that it turns on the pump.

Also, check for debris or corrosion that might keep it from floating up properly. If this switch fails the pump won’t turn on and your boat could take on sufficient water over time to do serious damage.

Through-hull Fittings

This Is a Proper SeacockEvery through-hull fitting in your boat is a potential hole that could sink you in a matter of minutes. Although they are out of sight and, at times, difficult to get at, through-hulls need careful routine checking, at minimum every three months. Many through-hulls such as engine-cooling intakes and sink or cockpit drains, tend to be left open continuously and the valves may stick in the open position. You should operate the valve by turning it on and off to make sure that when an attached hose fails you can stop the water flow.

As an additional precaution you should get wooden bungs (tapered soft wooden plugs) for each through-hull in your boat. (You can get them at most Marine Supply stores.) Make sure that they are the proper diameter to fit in the through-hull. Once you get them back to your boat, don’t just throw them in a drawer. Take each appropriate size to the through-hull it fits, drill a hole in the larger end and thread a string or monofilament line through and tie it to the through-hull fitting. When the inevitable happens you won’t have to go looking for the bung. Just reach down, put the tapered end in the hole, and press down until tight and the leak has stopped.

Remember, a two inch hole just a few feet below the waterline can sink a 30’ boat in just a few minutes.

Leave a comment

Filed under Boat Maintenance, Boat Operation, Boating News, Boating Safety

VESSEL SPARE PARTS LIST

The fact is that some things just disappear and no one knows where they go. There must be a stash of single socks and gloves somewhere in the heavens.

 The same thing happens over time on your boat. So now that you are finished or in the process of winterizing, check your onboard tool kit and spare parts to make sure none of those have disappeared into sock and glove heaven. That will give you the entire winter to either replace what’s missing or perhaps put the missing items on your Christmas list and perhaps Santa will surprise you.

Every vessel should have a basic mechanic’s tool kit onboard. This kit should include, at minimum, the following:

TOOLS

  • Socket set – 3/8 drive (3/8″ – 13/16″)
  • Open and box wrenches (3/16″ – 1″)
  • Screw driver set – slotted & Phillips
  • Crescent wrenches – 8″ and 12″
  • Pipe wrench – 1 3/4″ opening
  • Vise grips – 8″
  • Pliers – regular and needlenose
  • Channel locks
  • Assorted allen wrenches
  • Hammer
  • Wire cutters/strippers
  • DC test light
  • Volt/ohm meter
  • Utility knife
  • Hacksaw and blades
  • Tape measure
  • Spanner wrench(oil/fuel filter)
  • Drill and bits
  • Assorted punches
  • Spark plug wrench

MISCELLANEOUS ITEMS

  • Flashlight and extra batteries
  • Wire #10 and #14
  • Tie wraps
  • Electrical tape
  • Assorted screws, nuts & bolts
  • Two-part epoxy
  • Wooden bungs, assorted sizes
  • Silicon
  • Assorted electrical connectors
  • WD-40 or slick lube

SPARES

  • Fuses, assorted ratings
  • Bulbs, every type used on board
  • Oil filters
  • Fuel filters
  • Air filters
  • Impellers
  • Belts
  • Hose clamps, assorted
  • Hoses
  • Flexible fuel line
  • Oil
  • Transmission fluid

Leave a comment

Filed under Boat Maintenance, Boat Operation, Boating News, Boating Safety