Boat Books on-line
the fittings on a Junk Rig
mast must be either above
the yard or below the boom when the sail is fully raised.
These upper fittings will include the main halyard, the mast
lift and the
lazy jacks. To allow for the sail swinging around the mast the halyard
normally hung at an angle of between 30 and 40 from the fore and aft
Other fitting such as navigation lights, aerials and wind
be located above these.
The yard is the spar or batten
along the head of the
sail. This batten supports the full weight of the sail when hoisted so
be relatively strong. When the sail is raised and trimmed this batten
the peak of the sail.
is the top aft corner of any 'square headed' sail.
The battens are what give the junk rig
its distinctive fan
Originally made from bamboo these are nowadays made from a variety of
from wood to aluminium and more exotic modern composites.
Traditionally, the battens made for a flat shaped sail however, there
many recent refinements to make ‘bendy’ battens which give the sail
a more aerodynamic shape.
masts are normally unstayed to allow for free movement of the sail
For support an unstayed mast is normally keel stepped with reinforced
partners at deck level.
Masts have been successfully made from wood,
and steel as well as more expensive modern materials.
Skirt or Mast Boot is fitted
above the partners to any
keel stepped mast to prevent water getting below.
The boom is the lowest batten on a junk
sail. Unlike other fore
and aft sail rigs, the junk rig boom is only partially responsible for
controlling the angle sail and the forces are not as great so, it does
to be as strong.
is the lowest corner of a sail at the aft end of the boom where the
It could be argued that a junk sail has several clews, one on
that has a sheet span attached.
are short lengths of line or strap which help to hold the sail close to
They also determine how the batten will align, fore and aft, when it is
They need to be long enough to allow the sail to be trimmed fore and
allow the sail to be easily raised and lowered.
mast lift supports the front end of the sail bundle close to the mast
sail is lowered.
This line runs from the mast head outside the sail and is looped around
mast below the boom.
The tack is the forward lower corner of any
fore cornered sail.
The luff is the leading edge
or front part of any fore
and aft sail.
The main halyard is used to raise the
junk sail up the
As the junk rig tends to be rather heavy the halyard is often
rove in a
It is usually attached forward of the middle of the yard and
the block at the mast head then down to the base of the mast and back
The throat on a junk rig is
the part of the luff of
the sail just below the yard.
The function of this parrel is to control
the fore and aft
position of the yard. It also helps to control the lateral position of
P- Luff Hauling
This parrel controls the
As well as controlling the fore and aft position it also exerts a
on the forward end of the battens.
Q- Lower Luff
This parrel controls the
position of the boom and also
acts as a tack line holding the tack of the junk sail down.
The lazy jacks serve to tame the junk sail
during reefing and
dropping, holding the spars and sailcloth as they drop between the
It also acts a topping lift preventing the aft end of the sail dropping
is lowered or reefed.
These control the angle of the sail
depending on the wind
On the junk rig one sheet will control several battens via the sheet
Junk Rig Sheet Spans
These lines connect groups of battens a sheet.
Traditionally, the sheet would be connected to the sheet span via a
A euphroe is a wooden block with holes through it.
The friction on a line running through the holes allowed for the
the tension on the sheet spans.
It is quite common on western rigs to simply use double
line is really a
boom vang, whose purpose is to hold the boom down.
of any fore and aft sail is the trailing edge of the sail.
Boat Books on-line
junk rig is
becoming increasingly popular among western pleasure boaters because of
ease of use.
It is also becoming popular in
many different guises, as
home builders modify and improve on the basic principles to suit their
The low tec nature of the rig
makes it ideal for
experimentation, even using low cost poly tarp to make the sail
There are numerous examples of
boating folk using
variations on the theme on canoes, day boats, cruisers and even super
However, there are some constructional
considerations to be taken into account before you decide to
convert a boat
to Junk Rig.
Further information on Junk
Rig at The JRA and The junkrig