OCTOBER | NOVEMBER 2014 BoatU.S. Magazine | 95
of the transom and extend out behind the
boat, clearing the swim platform, if there is
one. Additional bracing of the transom area
is sometimes required to reinforce the hull
from the shock loading of a bouncing dinghy
in rough weather.
Weight is important when planning a
traditional davit-hanging system. Selecting a
pair of davit arms each rated for a maximum
of 300 pounds doesn’t mean it’s safe to carry
a 600-pound dinghy. Up to 75 percent of
the total weight of the dinghy and outboard
is in the stern. So one davit arm will always
be loaded much more heavily than the other
and may need to be reinforced if there’s any
question of its ultimate integrity.
Other configurations attach the davit
arms directly to the stern rail with additional
bracing to strengthen the railing support.
Olver says it’s essential to strengthen the
stern rail to handle the increased weight of
the dinghy hanging from the davit. It’s also
important to stabilize the davit arms so they
can’t move from side to side as the boat
moves. This lateral support is often done by
connecting the davit arms with rigid support
between the two.
The dinghy must be stabilized to prevent
motion when stored. The weight of gravity
pulling the dinghy down becomes a com-
pound set of forces when the boat is moving,
and every effort must be made to steady
and eliminate all movement. Most davit
systems that fail do so because the dinghy
was allowed to swing underway, or it comes
loose, and the combination of side-to-side
and up-and-down movements creates com-
plex loads beyond the engineered capacity of
the davit system. The twin-davit-arm system
is a proven approach for handling the din-
ghy and has much to recommend it. Some
companies offer removable arms that can be
taken off and stowed when necessary, such
as those from St. Croix Marine.
Another system that’s been around for a long
time was pioneered by Weaver Industries.
Called the Weaver Snap Davits, the system
involves attaching connecting hardware to
both the dinghy and swim platform. The
dinghy fittings snap into those on the swim
platform and you pull the dinghy up vertically onto the swim platform, either manually
or electrically, and secure it in a near-vertical
Swing-up or snap davits are easy to
install yourself, and work best with light
inflatables powered by small outboards.
traditional davit arms offer a reliable
solution, but the dinghy does block
access to the swim platform.
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