K S S N E W X C A T 3 3
Study Plan is available
Design No 362 (Composite construction E-Glass and PVC foam)
The novel beam system is based on simple, sliding beam parts.
The central accommodation supports the beam system and provides a
comfortable saloon for the off-watch crew or non sailing family members.
The hulls tuck under each side in the narrow condition. The rudder and
outboard operate in either the narrow or the wide condition.
The expansion and the raising of the mast can take place while underway
under outboard motor - for least time spent at the slip.
Most known catamaran beam systems are based on complex folding parts. The Kisskat beam
system uses box section beam parts which are attached to the hulls, where the beam part on
one side slides within the beam part from the other side, which slides within the central
unit. The width is expanded and then the beam parts are fixed in the wide operating condition.
The arrangement while in closed condition and changing width is stable at all times in calm
to moderate wave conditions.
The full length of one beam part slides within the other. A plastic and stainless steel worm gear, between
the beam parts, provides the force to slide, operated by hand or by electric motor. A lever or tackle system
can also be used. The trampoline becomes tight in the wide condition.
The beam parts are tapered outwards. The other half of the larger beam has a parallel section to pass
over the smaller beam part. Both ends of the smaller beam part are tapered.
The connection of the smaller beam part to the hull is a narrow structural member below and centrally
positioned to coincide with a slot in the lower face of the end of the larger beam part.
When expanded, the ends of the beam parts remain overlapped by 30mm, with the smaller beam part, within
the end of the larger beam. The fixing mechanism retains the two beams located relative to each other and
against a channel within the central unit. A notch at the end of each beam part locates with a matching
fixing pad, which is lowered onto the ends of the beam parts. It is held there with a ratchet strap,
applying downward pressure on both beam ends at the same time.
Where each beam part exits the central unit, a saddle contact area matches the beam part section shape.
On the small beam side, the saddle is 40 mm wide and smaller than the large beam section. This determines the
length of the large beam part, which stops just short of this saddle when in closed position.
A ratchet strap is wrapped under the beam part and pressure is applied at each of the four positions of the
beam parts in contact with the central unit, to cater for any reverse loading in wave conditions.
The low friction pads are used in the small contact areas.
KISS KAT BUILD, using KSS
A mould table, resin infusion and full foam sandwich structure
ensure the best light weight structure in the least build time.
The mould table provides a smooth gel coat finish for all of the
exterior except the joins and round bilge of the hulls. KSS half
hull shaping and kit assembly is the approach. The whole of the central
platform is first laid out flat from the drawings. Bend lines and
curved area are treated to allow shaping, before completing the inside
skin. The saloon sides and top are bent from a single panel, to which
the bulkhead and the forward panel are joined. Openings, recesses for
windows and edge treatment for joining are built into the parts while
being infused on the mould table. KSS build is unique to Kelsall Catamarans.
Length Overall LOA m
Beam Overall BOA m
Draft Dft m
Displacement D t
Sail Area sqm