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Seaward Yachts - Keel System
26RK | 32RK
| Keel System | Straight
Talk | Faq's
| Our retracting foils
are fundamental to our boat's performance, stability and versatility.
Without adjustable draft, you're typically forced to choose
between a boat designed for deep water, or a boat designed
for shallow water. Usually one boat can't excel in both depths.
Ours can. In deep water, with our keel extended, and with
its ballast low at the bottom tip of the keel, our boat is
very stable, and very seaworthy. In shallow water, with the
foils retracted, our boat can take you places other sailboats
can't go, and with the ballast in the bulb, the boat remains
stable at all draft settings.
Because our foils retract, our boats are
easily trailered. They sit low on their trailers so wind
resistance is minimized, and visability from the tow vehicle
is excellent. The boats float on and off their trailers
easily, and setup and breakdown is quick and uncomplicated.
Our keel is housed in a rugged fiberglass trunk that runs
from cabin floor to ceiling. This trunk is laid up as part
of the hull, and glassed to
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the deck, creating a very strong, almost monolithic boat. This
trunk is laid up as part of the hull, and glassed to the deck,
creating a very strong, almost monolithic boat. The keel moves
vertically, powered by a 12 volt motor, housed in a motor box
on deck, and controlled from the cockpit.
The keel itself is constructed of fiberglass with a fiberglass
composite inner core. The cast lead ballast is encapsulated in
the bulb and lower keel sections. The keel's outer fiberglass
skin is laid up as follows: Isothalic gel coat, vinylester hot
coat, 17 ounce unidirectional carbon fiber, 24 ounce unidirectional
E-Glass, and two layers of 2410 biaxial E-Glass.
The 12 volt motor moves the keel via quarter inch 7x19 stainless
cable, rated at 10,000 pounds. The motor/winch assembly is built
by ITT-Jabsco, is stainless, and is rated at 2,000 pounds. Bronze
turning blocks route the cable to give it mechanical advantage
(three to one for the 26RK, and four to one for the 32RK) so that
no component is stressed to more than 40 percent of its rated
capacity. The blocks are built for us by Edson, and are rated
at 10,000 pounds breaking strength
The upper keel arm is the part of the keel that remains in the
keel trunk when the foil part of the keel is fully extended. It's
function is to transfer the lateral loads generated by the keel
as the boat heels. On our boat, these loads are spread throughout
the boat, since the upper keel arm fills the truck at all times.
This upper arm is constructed of #304 stainless steel box tubing.
There are three holes in the upper keel arm, designed to receive
a pin of the same diameter, which is used to take the keel weight
off the motor/winch mechanism when servicing the mechanism.
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