Every sport or hobby has its mavens of minutiae, like the baseball fan who can recite the Brooklyn Dodger lineup of 1948 or the political wonk who knows eight ways to stop a filibuster. Well, boating has guys like that too, and I’m one of them. I’ve been collecting nautical trivia since I was a kid. It’s an obsession, and a good one too, since I’ve found that many of these little esoteric facts have helped me get more out of my time on the water, and impressed a few friends along the way.
Head Off Trouble
Telling guests that using too much toilet paper will clog the plumbing is not enough. Be specific. Tests show that six squares at a time is the maximum.
You use approximately a gallon of gasoline per hour at wide-open throttle for every 10 horsepower. Not super accurate, but surprisingly close.
Keep It on the Plate
Avoid “round” food, ones that roll around on the plate. Choose hamburgers over hot dogs, niblets over corn on the cob and mashed over baked potatoes. And always square off your meatballs.
You know the weight of your passengers, and maybe the gear. What about the sloshy stuff in the boat? It adds up fast.
1 gallon of fresh water = 8.3 pounds
1 gallon of diesel fuel = 7.1 pounds
1 gallon of gasoline = 6.6 pounds
2'4" The absolute minimum berth width that any normal human will be comfortable with. The length should be 4 inches longer than your height.
Approximate fuel consumption at cruising speed can be estimated as follows:
Diesel - 5.3 gallons per hour per 100 hp
Gasoline - 7.8 gallons per hour per 100 hp
Number of hours you can expect a gas marine engine to typically last before needing major overhauls. A diesel lasts about 5,000 hours. No hourly figures exist for outboards, but 10 to 15 years in salt water is common.
It Never Stops
To calculate how much it will cost to keep a boat going, figure to pay from 2 percent to 5 percent of the original cost (new) per year in maintenance.
Sound of Silence
The most effective sound insulation is layers of foam core to reduce low-frequency sounds, thin sheets of lead to cut down on higher-frequency noises and Mylar or aluminum foil sheathing to protect the insulation from heat. Look for a minimum combined thickness of one inch.
Many engine compartments, and the engines in them, are starved for fresh air. increasing a 3-inch round vent to 4 inches almost doubles its volume.
For every foot of draft in fresh water, your boat will rise almost one-quarter inch when immersed in salt water. A boat drawing three feet on Lake Huron will draw only 2 feet 11¼ inches in the Atlantic Ocean.
Quick and Dirty Method
For small, lightweight runabouts of 24 feet and less, use the 1:25 rule. For every 25 pounds of weight (including engine, gear, fuel and crew) you’ll need approximately one horsepower to get on plane and cruise at a reasonable speed.
Hanging by a Thread
The length of a bolt is correct for the job if at least two threads are exposed past the nut after tightening — the first couple of threads do not have full strength.
Thunder, and the storm that comes with it, is nearby if it crashes and bangs. It is far off if it rumbles like timpani, and very far away if you see only the lightning but hear nothing.
When barometric pressure starts falling, foul weather is approaching. The barometer falling 0.1 inch or more per hour says that a major storm is close.