1 METRE YACHT
This
is the smaller of the two International class yachts
sailed at Three Rivers Radio Yachting Club. It is also
proving to be the most popular.
The class rules are intended to control costs whilst
allowing the home builder to construct an inexpensive and
competitive boat. There are limits on hull construction
materials, draught, ballast weight and total displacement
while the three permitted rigs have tightly controlled
dimensions.
As a result of these restrictions, a well-built and
rigged yacht should remain competitive for some
considerable time. The popularity of the class, which is
finding strong international support, is also helped by
the size, being very easy to transport.
Maximum length is 1m (39.4ins), mast height is 1.7m
(67ins) and weight is 4kg (8.81bs) minimum.
1 Metre with "middle" rig
MARBLEHEAD YACHT For many
years this class has been the backbone of
competitive racing within the club and it is here
that "High Tech" is the norm rather
than the exception. The Marblehead rule restricts
length to 1289 mm (50 ins) and sail area to
0.5161 sq. m (800 sq ins). |
Marblehead with
"high tech" swing rig
RADIO EQUIPMENT
The radio gear
used to control a yacht is the same as that used for
other R/C sports except that 35Mhz equipment must not be
used. 27Mhz am (amplitude modulated) equipment is
generally available at moderate cost while the
technically superior 40Mhz fm (frequency modulated)
equipment is also widely available at slightly higher
cost.
In each if these bands several different channels or
frequencies are available, controlled by matched pairs of
plug-in crystals used in the transmitter and receiver. By
the allocation of a suitable channel to each yacht,
racing can take place without interference.
Standard or waterproof servos are mounted within the hull
and are used to control the rudder, while the setting of
sails is managed by "sheets" controlled by
either drum type multi-turn winches or lever arm high
power servos also mounted within the hull. The receiver
and batteries are usually contained within waterproof
pots.
Winches are made by specialist manufacturers and lever
arm systems are available from the well known names in
radio control. It is usual to power the equipment from
rechargeable batteries of the nickel cadmium or metal
nickel hydride types.
HULLS & FINS
The majority of
yacht hulls are moulded in either GRP, carbon fibre or
kevlar with a growing minority made out of thin planks of
wood. The 1Metre class hull is limited to GRP, wood and
certain plastics, while most other classes are
unrestricted in the use of materials.
Moulded hulls are available from commercial or
semi-commercial sources and you will find that most of
these suppliers sail their own boats.
For a "one-off" hull from a published plan,
planked construction is the easiest for a home builder
and can utilise balsa with a GRP or carbon fibre skin or
varnished cedar as the main building material.
Long thin fin keels for RM, and 1M classes are available
in moulded form from the same sources as hulls. Carbon
fibre, GRP or wood are the main materials used. Lead is
used for ballast in the form of a bulb or winged format,
depending upon the class.
SAILS & RIGS
Depending upon the class rules, masts are made of aluminium or carbon fibre. The mechanical fittings associated with rigging and control can be manufactured at home from simple materials or can be purchased ready made from model yacht suppliers. Sails are made from lightweight sail making materials such as woven polyester (dacron), mylar film or from polyester draughting film. This latter material is widely available and has encouraged many sailors to "roll their own" instead of purchasing sails ready made from commercial and semi-commercial sources.
Marblehead yacht showing lightweight carbon fibre "swing rig"