Copyright © 2001 - 2018 by B. Kohler All rights reserved
DUO 425 the affordable parallel (biplane) rig cat
the fastest cat for your money
The DUO 425 was the first parallel rig cat designed for amateur construction. The prototype was shown on the boat show in Duesseldorf 1984. We have the most experience with this sort of rigs. Many very fast and record breaking catamarans used and use this configuration.
I lost count how many DUO 425 are sailing worldwide, but it has to be more as 1000.
This is the easiest to build cat imaginable. Transport on the roof of a car is no problem. Set up time about 20 minutes.
For example, a hull is build from only 16 main parts.
The boat can handle a lot of wind. I sailed the boat till wind force 9 without any problem. And belief me, the boat is faaaast ! On the other hand, the boat is very stable through the parallel (biplane) rig.
The hulls are wood/epoxy constructions. Made from 4 sheets of 4 mm and one sheet of 8 mm plywood + 6 kg of epoxy. The rigs are two wind surfing rigs. Vertical kick-up rudder automatic. Sort of "matched hole technique" used to line up i.e.built the hulls. The construction time is about 120 hours. Without doubt, this is the fastest
catamaran you can build for the time and money spend.
Length : 4.25 m
Beam : 2.10 m
Weight hull: 17.00 kg
Weight all in: 44.00 kg
Sail area: up to 16m2
The mast compartment with lower mast bearing
Hulls ready to be closed
The bow construction
Dagger board rudder with automatic cick up system
The plans are delivered as E-book with a step by step building instruction
and 18 drawings. Plans cost: Euro 50,-