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Designer comments:
We have been wanting a good all-around hard tender to be towed behind
our larger sailboat for some time. It needed to be easily rigged for sailing, be
lightweight, outfitted with electric power, and have more modern flair than
the traditional looking wooden tenders.
The
L’Arche
dinghy is the result of that seemingly simple design brief. A free
standing cat-rig was the obvious choice for being easy to setup and light-
weight, while keeping the center of effort low to help with stability. She has
proven to ghost along with barely a ripple on the water or she gets up and
goes when the wind picks up. Using foil-shaped rudder and daggerboard,
she is responsive without the drag of simpler designs.
Instead of purchasing an expensive commer-
cial inboard electric drive unit, we decided to
design an electric system with easily obtained
parts. With the lower unit of a 55 lb. thrust
trolling motor and a 12 vdc deep cycle battery,
she hits a top speed of 4.2 knots or cruises
along, whisper quiet, at 3.5 knots while con-
suming 15 amps for a safe 3 hour sail. She is
rigged to be plugged into her mother ship to top off the batteries at night, but with the opt
of regeneration capabilities and removable solar panel, her charge times can be greatly r
duced.
Construction is of 1/2-inch foam core and she is built one half at a time. A strongback wit
molds and battens are set up to form a female mold for the planking of the dinghy. Once
first half of the hull is planked, glassed, and bulkheads are in place, the hull is removed a
set aside. The molds are then reversed on the strongback and the second half of the hull i
built in the same manner as the first. At this point, the two halves are joined together and
the hull can be removed from the molds and the outside layers of glass can be applied. All major components are foam
core, creating a very stiff but lightweight structure. The building technique is simple to follow and large professional po
tools are not required.
to watch a video of
L’Arche
from construction through completion and sailing.
Specifications:
LOA.
10' - 10" (3.30 m)
Beam
4' - 10" (1.47 m)
Draft/hull
0' - 7" (18 cm)
Draft/board
2' - 2" (58 cm)
Sail Area
70 sq.ft. (6.5 sq.m)
Displacement:
600 lb. (272 kg)*
Boat Wgt.
200 lb. (90 kg)
*Rigged with 2 crew and electric propulsion
Kurt A. Cerny
Cerny Yacht Design
Email:
Web:
L’Arche
Sailing Dinghy
Designed and Built by Kurt A. Cerny