Instructions below are
from Sparcraft's website per 2013-03-08 Original page can be found by
Setting - tuning - maintenance
FITTING RIGGING & SPREADERS
will need to plan your work area to allow for the width of spreaders and
an adequate area at each end. Lay out a range of standard tools so that
they are easily to hand. You will require vinyl tape and a sharp knife
but no specialist tools are needed other than those you would normally
have in your tool box. Be careful not to cut through any messenger lines
when unwrapping and use the packing material for padding. Check the
spars carefully for transport damage and make sure that there are no
loose fittings in the packing materials.Check that all the messengers
are in place and secured separately and fit the mast collar into place
Electrical wiring should be installed using the messenger (if not
already fitted) and fit your mounting brackets for electrical equipment
to the masthead (but not the equipment). Lighting can be checked with a
12 volt battery if required.
Identify all the standing
rigging, main, intermediate, forestay, backstay, etc. and fit them to
the mast. They will be one of 4 types. Swaged Eye Into External Tang.
Fit pin and secure with split pin, ensure that the pin is taped over to
stop rigging and sails catching on the split pin. Shell Terminal. The
shell terminal will be fitted to the shroud. To fit simply manouvre the
shell through the hole in the mast wall. If you wish you can tape the
shroud in position around the mast to ensure that there is no movement
of the shell during the stepping procedure. Once the mast is in place
the shells are securely held in place by the rigging tension.
On SPARCRAFT OCEAN masts
with cast spreader brackets, drop the shrouds through the relevant holes
in the spreaders - they will be held captive by the rigging tension.
Ensure there is a stainless steel cup fitted between the stemball and
the spreader bracket. With double spreader rigs fit the cap shroud in
the forward hole of the spreader and the intermediate in the aft hole.
Through Bar Spreader Fittings On Sparcraft Performance Spars. Push the
stemball through the larger hole in the spreader bar then locate it on
the seat provided. Follow the instruction provided. T Terminal. Offer up
to the T Terminal seat at a 90°C angle to allow the T to enter its seat,
then swing through 90°C to secure it. Fit rubber stopper or stainless
retaining plate to avoid accidental release of T Terminal (especially
important with running backstays).
fit the spreaders using the pins provided and tape over the whole
assembly to stop ropes or sails snagging the spreader pins. Secure the
rigging to the spreaders with the cap shrouds at the front and
intermediate shrouds at the back of the spreader tip fitting. Make sure
that when the mast is stepped the spreaders have a slight angle upwards
to ensure the proper transfer of load from the shroud through the
spreader to the mast. Again make certain that the cup washers are in the
stemball rigging seats where fitted, and that the mast collar is fitted
if the mast is keel stepped. Check that the turnbuckles can be fully
adjusted and that the threads are not damaged. These should be
lubricated with WD 40 or similar. All the running rigging should be
fitted using the messenger lines, which should be tied and taped to the
new halyards. Finish installation with "figure of eight" knots on the
halyard ends. Prepare for stepping by tying all rigging loosely to the
lower part of the mast, except the forestay (furling jib) which should
be loose, ready to attach when the mast is hoisted.
WIND INDICATOR & INSTRUMENTS
It is convenient to
install the wind indicator and instrument sensors whilst the mast is on
the Quay. If your appointed crane driver is experienced it is unlikely
to be damaged, but the safest way is to fit the masthead instrumentation
after the mast is stepped.
MEASURING THE YACHT
Before stepping it is wise
to check that the mast step is centrally fitted along the centreline of
the boat as any inaccuracy can create mast tuning problems. Check the
chainplate deck fittings to be sure that the turnbuckles are compatible
in pin size, width and clearance. If you are stepping a mast to the keel
then measure the distance from step to deck and check this against the
"bury", the distance between the mast base and deck point. This should
ensure that there are no embarrassing moments when the mast is offered
STEPPING THE MAST
TENSIONING THE MASTHEAD RIG
Before stepping, make sure that there is a clear run for electrical
wires. When hoisting by crane, it is best to rely on experienced staff
who regularly step masts as they are aware of the loads and wind effect
involved. The mast should be lifted with a soft strop at, or just above
the centre of gravity. The strop must be secured so that it cannot slip
upwards. The heel can then be swung into position. Secure the forstay
and cap shrouds, steadying if necessary with the halyards. Once the mast
is secure, the strop can be removed and you can start on the important
task of rig tensioning.
The top of the mast must
be vertical in the yacht, so use the main halyard and measure carefully
to a fixed point on each side of the yatch. Hand tighten the cap shrouds
to centre the mast.
The shrouds can now be tensioned by adjusting each turnbuckle in turn by
approximately 3 turns at a time per side. The mast stays in aligment as
the tension is increased. The forestay and backstay should be tightened
to about the same tension as the upper shrouds, allowing for
approximately 1° to 1.5° of aft rake. This rake will improve upwind
performance and allow the rig to set in the correct position when the
sails are set. For a 10 metre mast, the top needs to be set aft by
approximately 200 mm. Mast rake will also contribute to the weather or
lee helm affect on your yatch. Increasing the rake aft will increase
helm and vice versa.
Some weather helm, when sailing is desirable for best performance and
control. If you have a double spreader rig then tension the
intermediates next. These should be tensioned slighty looser that the
cap shrouds to allow for natural mast bend and stretch from the shroud.
Check the alignment of the mast by regulary sighting up the rear sail
track. When you are confident that the mast looks correct so far,
proceed with the tensioning of fore and aft lower shrouds, or lower
shrouds and inner forestay. Certain classes may have specific
measurement and tuning information which can be used as a supplement to
these guidance notes.
TENSIONING THE FRACTIONAL RIG
with spreaders raked aft
raked spreaders support the mast sideways and additionally fore and aft.
When the tension is increased the spreaders drive the mast forward
creating pre-bend. It is essential to work carefully stage by stage to
achieve the correct rake, pre-bend and tension.
Start with the cap shrouds, centring the mast in the yatch (see how to
centre the mast in the "Tensioning the Masthead Rig" section). Adjust
rake with the forestay and then tension the backstay to induce mast
bend. Work from the top tensioning each cap shroud about two turns at a
time, followed by the lower shrouds and intermediates. Return to the
caps and repeat the exercise until the mast is under the required
tension. The required tension won't be known exactly until you go out
sailing, but each shroud should be fairly snug (see Masthead Rig Tuning
for Safety & Performance). Check regulary for vertical alignment along
the sail track.
with spreaders raked aft
Adjust the forestay to get
the required amount of rake. Then each cap shroud should be tightened by
two or three turns to increase tension, checking that the mast stays
vertical. As tension is increased this will drive the mast forward,
If fitted, tighten the intermediates and lower shrouds which will reduce
pre-bend. Some pre-bend is however desirable, so leave about 6-7 cms
set. At this point the caps, lower shrouds and intermediates should be
tight. Backstays are the last adjustment to make, as they tension
against the other rigging. When the spreader angle is about 15° or less
then more tension is required in the backstay to support the mast
correctly aft. When large angle spreaders are fitted (more than 15°),
they will also support the mast, so the backstay do not have to be
tightened so much.
PLANNING FOR SAIL TRIALS
MASTHEAD RIG TUNING
You have now completed as
much as possible by "dock tuning" the mast. If it is out of column then
go over the procedure again, starting from the caps. Now plan to tune
the rigging on the water !
On your first sail trials take a crew with you than can sail the boat
whilst you concentrate on adjustments. Choose flat water with no more
than a force 3 wind. Sailing to windward check up the mast track for
aligment which should be straight. Make adjustment to the leeward shroud
which should be under very little load, than track the boat to adjust
the other side.
With the sails up it is useful to mark the halyards in their sailing
position with an indelible pen or twine.
for Safety & Performance
Systematically alter each
shroud, working from the top set, keeping the number of turns the same
from side to side. Adjustments should be carried out on the leeward side
where pressure is slack or reduced. Check the reaction before
proceeding. With increasing pressure on the sailplan (about 20% of heel)
the leeward shrouds and intermediates should just begin to slacken.
The forestay can be finally adjusted for the correct amount of rake.
FRACTIONAL RIG TUNING
FRACTIONAL RIG TUNING
with aft facing spreaders
This type of configuration
requires increased shroud tension to ensure that the rig does not go
slack. It is important to keep these masts relatively straight as this
will provide best performance. Too much bend will cause rigging to
slacken with an associated reduction in performance. As before, adjust
the leeward shroud whilst it is not under pressure.
CAUTION : If standing backstays are fitted they should be used to
carefully trim the topmast to improve upper sail shape and reduce mast
panting in waves. If it is overtightened the backstay could induce too
much bend allowing the shrouds to go slack.
with in-line spreaders
The in-line fractional
spreader configuration should be set up as for the masthead rig, the
only difference being the addition of running backstay to tension the
forestay. More mast bend can be expected and the sailmaker will cut the
mainsail accordingly. The mast should always be set up with some
fore/aft bend as these masts can invert, particulary in stronger winds.
More experienced crew handling is required to control both tacks and
gybes. If the runners are not made up in time after a gybe there will be
nothing to stop the whole rig falling over the bow. When tacking keep
some tension on the mainsheet as this should hold the mast in position
if runners are not secured.
CAUTION : The checkstays allow you to trim the exact amount of fore/aft
mast bend around the middle section. Over tightening them relative to
the running backstay could cause a mast inversion !
REDUCING POWER BY REEFING
At the completion of every
stage remember to fit and open split pins, to lock the rigging to the
yatch. When you have completed tuning it is advisable to seal these pins
with tape so that they cannot catch sails or fall out.
As the wind increases in
your sails you need to progressively flatten them to reduce power. This
can be achieved by ensuring that halyards are tight (with no sail
wrinkles along the luff) and that the clew of the main is at maximum out
If you then still have too much pressure the sail area has to be
reduced, either by changing sails or reefing. Modern systems are now so
efficient that with a little practice on the system, it is
straightforward to reef sails, even shorthanded in strong wind.
You will probably need to re-adjust the leech line. Tension it just
enough to stop the leech flapping and remember to release it when you
shake out the reef.
BOOM - SINGLE LINE REEFING
Before you leave the dock, the reefing lines should be rigged. It is
very difficult to do this later, often when you may need to, on a
rolling or sloping deck with the boom end over the water. Your boom is
fitted with all the equipment for reefing. Reef lines should be loaded
so that they pull the new clew down to the boom track and aft, to
flatten the sail. When reefing ease the boom vang. Ease the halyard and
the luff on the sail will fall. Hook on the required tack cringle to the
boom reef hooks and re-tension the luff.
Now tighten the reef line by turning it around a winch. Use the locking
lever at the forward end of the boom to secure the reefing line. Sheet
the mainsail and re-adjust the boom vang. Shaking out reefs is just as
easy. Just reverse the process, but watch out for the outer end of the
boom falling and swinging into the cockipt. For single line reefing, see
With SPARCRAFT's automatic reefing boom system, one sailor working from
the cockpit can reef a sail in under 30 seconds by tensioning one of the
reef lines and easing the main halyard. The tension on the other lines
is automatically adjusted and sail reduction can be as much as 75%. This
system offers outstanding efficiency and safety for short handed or
single handed sailing.
LAZYJACKS & BATTENED SAILS
USING THE BOOM VANG
A lazyjack system can be
fitted to collect the sail when it is reefed or lowered. This is
particulary useful for fully battened sails. You may need to check that
the lines do not foul the batten ends when hoisting.
The boom vang is a
powerful sail control and should always be used with care. It tensions
the leech of the sail and will improve sail shape on the wind and when
running. In stronger winds the correct vang tension will stop the leech
from twisting and creating a rolling motion downwind with light winds,
it is easing the mainsail leech and replace boom topping list. It is
always a good practice when bearing away in windy conditions to ease the
boom vang, in order to avoid overloading which can cause loss of control
or damage to the boom.
BASIC SAIL SETTING
Good crew preparation will make spinnaker setting easy. Plan who will do
what jobs, including spinnaker halyard, guy an sheet. Launch and set the
spinnaker as quickly as possible to reduce handling problems. Always
take care when setting the pole, making sure that it is steadied by both
a pole uphaul (to support the weight) and downhaul (to stop the pole
For best performance your
sails need to be set correctly, achieving an aerofoil shape with the
correct amount of depth (draft). It is important for adjustments to be
made for differing wind conditions.
Start by tightening (or slackening) the luff of both mainsail and genoa
so that wrinkles just disappear when sailing to windward, as any
slackness will make the sail full, reducing pointing ability. Make sure
that the foot is adjusted correctly for the conditions. In light winds
your sails need to be more powerful, so some foot fullness is required
in the mainsail. Do not oversheet the genoa. In stronger winds (when the
boat is heeling) reduce mainsail power by securing the foot very
tightly. This will reduce the fullness throughout the whole mainsail
area. The genoa can be sheeted harder. The sheeting position for the
genoa should be moved progressively aft as the wind increases. This will
open the upper leech, reducing pressure mainsail backwinding and heel.
When sailing downwind, trim the leech of the mainsail so that there is
some twist, but not too much. Downwind rolling can start when the wind
is strong and the leech is too far open.
Always be ready to reef the mainsail, or reduce genoa area if the
weather is getting worse. In strong conditions, all sails need to be as
flat as possible to reduce power and heel. Remember to adjust the leech
lines. Left flapping, the material will shatter and remain slack. If
left tight, the leech will hook and probably stretch.
Different sailmakers use various techniques in achieving the desired
sail shapes for particular boats. Consult you local sailmaker for the
ideal settings for your sails.
FITTING NEW HALYARDS
Masthead cables are fitted
to all new masts, via a plastic conduit tube. These exit at the
masthead, heel and at half height, ready for installation of lighting or
other equipment. Check that there is no damage to the outer PVC cover
before installation. It is especially important because any electrical
discharge can create corrosion, particularly around fittings. We
recommend that all electrical work is carried out by experienced
specialists who are familiar with the problems relating to salt
corrosion and electrical discharge.
When changing or checking
halyards always load a messenger line through the mast and sheaves. If
halyards are jamming, check if it is twisted with others. A new
messenger line can be dropped to clear twists, if required.
Chemical corrosion can take place between alloy and stainless, so it is
very important to introduce a chemical barrier between spars and
fittings. Corrosion will take place under the fitting often where it
cannot be seen so use a zinc chromate paste, silicone or butyl rubber
layer for any new fitting. When using fastening, stainless screws are
strong but check for corrosion regularly. Cut them to the correct bury
length otherwise they may snag or damage halyards. Monel rivets are
strong, with less possibility of chemical reaction with the alloy. When
drilling, take care not to drill into the electrical conduit.
It will be necessary to
work aloft at times to carry out maintenance. If you are unhappy aloft
get a crew member who is experienced to undertake the work. Don't put
off the work ! Check your equipment, starting with the Bosun's Chair and
halyard. You will need to be comfortable aloft otherwise it will be
difficult to concentrate. The halyard must be in good condition
particulary around the shackle and top three feet. A second halyard must
always bee connected for safety. Never rely on snap shackles as these
can snag and release. Use a deep bag for your tools, remembering that
any tool dropped may injure someone below, or the deck. A messenger line
can be useful for longer jobs, enabling tools to be raised and lowered.
Use an experienced assistant who is familiar with winches. Climb with
your feet and hands as your assistant winches with at least three turns
around the drum. This is faster and more efficient. Make sure that your
assistant makes off the halyard end to a secure cleat, or ties it off
around a winch.
Trim your height so that you can work efficiently and tie yourself to
the mast with a short line to lock yourself in position.
Your assistant should follow your progress, warning of passing waves
which magnify the yacht's movement at mast height. Instructions should
be shouted clearly. When lowering, make sure that the halyard tail is
clear and ease the halyard around the winch drum. It is important to
have a good footing and to be watching the person up the mast. The
safest and most comfortable way down is slowly and smoothly.