The DUO 425 was the first parallel rig cat designed for amateur construction. The prototype was shown at the boat show in Duesseldorf in 1984. We have the most experience with this sort of rigs. Many very fast and record breaking catamarans used and use this configuration.
I have lost count how many DUO 425's are sailing worldwide, but it has to be more as 1000.
This is the easiest to build cat imaginable.
For example, a hull is built from only 16 main parts.
The boat can handle a lot of wind. We sailed the boat in a force 9 without any problem. And belief me, the boat is faaaast!
The hulls are wood/epoxy construction. 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. There is an automatic vertical kick-up rudder. A sort of "matched hole technique" is used to line things up when building the hulls. The construction time is about 120 hours
working on a hull
The mast compartment with lower mast bearing
Hulls ready to be closed
The bow construction
Dagger board rudder with automatic click up system