Boating and Sailing.pdf - Moja ladja

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Part 1: Getting Started in Boating
Boat Bytes
There are high-performance
plastic props out there, but
most never stack up to steel
props in head-to-head performance
tests, and when it
comes to durability, the slightest
touch on an oyster bar makes
them vaporize.
Props for Electric Motors
Plastic props are very inexpensive, which is the only
reason they have any chance at all in the market. They
are like the little wheelbarrow-type tires put in modern
cars as spares—adequate to get you home in an emergency,
but not really up to the rigors of daily use in
anything much beyond a 10-horse kicker.
Prices on typical plastic props for V6 motors run
around $50 to $75, a good deal as insurance for the day
your stainless-steel prop falls off (sob!) in deep water
due to a loose prop nut.
The plastic, nylon, or Lexan props supplied with electric trolling motors do a good job
due to their low speeds and modest horsepower. I’ve chewed several of them up pretty
badly, but they still hold their blades and keep on functioning.
Look Out!
When installing a plastic
trolling motor prop, tighten the
lock nut with your fingers only.
Tightening the nut with pliers may
distort the hub or even cause it to
crack.
Trolling motor props are available in three- or fourblade
“weedless” models with large barrels and small
blades, which are designed to cut through the thick
weeds found where largemouth bass, pike, and other
species live.
Weedless props are not quite as efficient as standard or
“power” props in open water. Power props are usually
two-bladed and have a smaller hub. They’re a better
choice for those who have to deal with strong currents
or wind in open water.
Both weedless and power props for trollers are inexpensive, ranging from about $10
to $30.
Counter-Rotating In-Line Props
It sounds like Engineering 101, doesn’t it? But two props on a single engine make sense
for many boats. The concept, first perfected by Volvo Penta in 1983, combines a righthand
and left-hand prop on the same shaft, one rotating each way. Mercruiser now markets
a version, and Yamaha has outboard models.
In-line systems provide a sort of “four-wheel drive” for boats, with amazing traction in
hole shots, blazing acceleration, white-knuckle cornering, torque-free steering, and very