CM2 51 Catamaran


CM251 Performance cruising catamaran designed by Schionning designs.
Specifications CE spec:
.        15.5m – Length.
.        7.7m – Beam.
.        6400kgs -Displacement light ship.
.        8365kgs – Displacement.
.        0.5m – Draft
.        20m – Mast height.
.        2m – Headroom in hulls.
.        2m – Headroom on bridge deck
.        Bridge deck clearance @ 8365kgs displacement  0.95m
.        Beam to length ratio @ 8365kgs displacement  13.04:1
.        340L – Fuel capacity.
.        4 x 200L – Water capacity.
.        2 x 38-40hp Inboard diesel shaft drive.
.        7.5knots – Motoring cruising.
.        12knots – Motoring top speed.
.        12-16 knots – Cruising speed.
.        25+knots – Top speed.

.        The Standard CM51 built using epoxy resin infused composite
E-Glass, 80-130kg/m3 Foam core achieving optimal weight and strength. Carbon
used extensively in locally reinforced structural areas.
.        The Carbon CM251CR built using epoxy resin infused composite
Carbon, 80-130kg/m3 Foam core achieving optimal weight and strength.
.        Externally-spray finish Awl Craft 2000/Alex seal in light solid
colour of choice/Anti-slip/ Antifouling barrier coatings.
.        The CM51 is primarily designed for the purist, experienced and
adventure cruising racer sailor who wants an efficient fast performing
sailing design that is spacious due to its open plan saloon and cockpit.
.        Designed as a lightweight owner cruiser racer or for the
performance charter owner.
.        Keeping the structure at a low optimum weight is due to a strict
build process achieved from many years of experience building light weight
multihulls using the resin infusion process where it counts getting the
optimum wet out ratio every time.
.        The hull is infused in a female hull mould in a 3 stage process by
doing this allows us to use a core that has no infusion grooves or slot to
feed the resin which increases the resin content. The first stage being  the
outer skin which is infused in a first stage on to the epoxy primer coating
in the mould. The second stage the core is carefully tailored and vacuumed
in place with the optimum adhesive paste, once cured the core is then long
boarded prior to the final internal laminate is stacked and infused. The
advantage of infusing the final internal laminate instead of wet lay-up and
bagging is that we will not have creases and folds  in the fibre which does
not allow the fibres to load evenly therefore not getting their full
.        This superior finish is a key factor to reducing the weight of the
hull and deck structure as we fair and paint the majority of the internal
surfaces. This does add many man hours however we see prefer not to pay the
weight penalty of panelling to cover up the internal hull.
.        Due to the reduced to weight of the main structure along with
carefully choosing gear we are able design an efficient fast easily driven
.        Bows are long slim easily driven with A-symmetric hulls flared
inboard giving the important reserve buoyancy when driven hard reducing the
hulls from burying at high speeds and larger waves action.
.        This has also provided additional volume in the forward cabin.
.        Centre of buoyancy is located aft of the middle of the hull with
the weight concentration strictly located closer to mid ships by shifting
forward the inboard shaft drive diesel engines reducing the pitching motion
at sea and giving the optimum hull rocker starting further forward.
.        Water and diesel tanks located mid ships below cabin soles just
aft of the mast lowering centre of gravity with additional fresh water
ballast tanks aft for trimming the bow up for downwind legs.
.        Angled inward carbon dagger boards are standard.
.        The bridge deck living area has been shifted aft with the bow
section proportionally lengthened with a shorter over hang at the stern
reducing bridge deck slamming.
.        Forward double bunks are located lower in the forward section of
the hulls due to the additional space available due to the A-symmetric bow
.        The Saloon and cockpit measures 6.3m in length and is designed to
be open plan with a 2m wide cockpit door way opening, designed with
removable modular dinning tables allows versatility by moving the furniture
and removing items for racing regatta’s and versatility for charter work and
.        The boom has increased in length with the main sail track on the
transom beam for maximum stiffness and optimum weight saving. The increased
boom length increases sail area and reduces the mast height and lowers the
centre of effort improving the stability/righting moment.
.        Reducing the weight reduces the mast height and sail area for its
length. All of which reduces weight aloft and improves the stability.
.        The hull free board is kept low to reduce wind age and importantly
reduces excess weight.
.        The cross beam is curved for increased stiffness but more
importantly it increases the wave clearance when pressed hard under sail.
.        The steering positions are versatile as they can shifted inboard
when the helmsman want some shelter from the elements and outboard for
optimum view looking down the centre line of the bows and with 360 degree
view over the cabin top from the raised step. 360 degree is vital so at to
being in control when at the helm.