Ocean Pointer/West Pointer Skiff Self-bailing?

[D]

Any more pictures of West Pointers/Ocean Pointers anywhere? I have the study plans here but can't figure out how the cockpit is self-bailing. Doesn't self-bailing mean that any water that enters the cockpit is drained by gravity with enough flotation in the bilge to keep the hull above the waterline?

[Wild Wassa]

On our little dinghies we install venturi self -bailers, made by Ronstan. The boat needs to be moving for this type of self-bailer to work.

Warren.

[ 10-22-2002, 12:53 AM: Message edited by: Wild Wassa ]

[Meerkat]

The general idea is called eduction. This is where a small of fast moving liquid (or air) will pull along or lift a larger slower body of liquid. The US Navy uses pumps based on the principle for dewatering flooded spaces.

For a dinghy bailer, the fast moving water outside the hull effectively sucks the standing water on the cockpit sole out through one-way flapper valves. These are usually a metal plate hinged at the forward end (and possibly with a spring to help it stay shut when the boat isn't moving), a rubber gasket larger then the thru-hull and the thu-hull opening itself. At rest, the pressure of the water against the metal plate (and possibly a spring) seals the rubber gasket against the hull and so seals the thru-hull (theoretically: the plate is not warped, the gasket is in good shape and there is nothing interfering with the surface the gasket seals against). As the boat moves, the dynamic water pressure pulls the plate away from the hull and the vacuum created pulls water or air out.

[chapq]

D-- the Ocean Pointer has a couple of valved scuppers in the transom to drain the cockpit.