MALIN BURNHAM ON
TUNING AND TECHNIQUES
(September 1966 / May 1967)
Early in 1966 Malin Burnham gave a series of lectures in
Australia by invitation of the Pittwater Fleet and the Royal Prince Alfred
Yacht Club. Because all of our members are interested in the advice and
suggestions of so successful a Star sailor as Mr. Burnham, we are publishing
here the first part of a report of his lectures compiled by officers of the
sponsoring fleet. It should be understood that there is no official Star Class
literature on rigging and tuning, and that the opinions expressed herein are
those of Mr. Burnham. - Ed
Fundamental Principle
There
is no perfect way of doing any of the items encountered in Star boat racing,
but when one way of carrying out a certain item is related to the many other
items then perfection is achieved.
The
three factors requiring attention for efficient and successful racing are: (1)
hull; (2) sails; (3) skill of skipper and crew.
The Hull
A glass‑smooth
finish is required, not necessarily with a high gloss. It is essential to
remove the boat from the water when not in use in order to keep a good hard
enamel or epoxy finish. Should even the smallest of cracks appear they must be
filled with epoxy filler in order to prevent the timber absorbing water.
Should
fine specks of material appear on the hull, or orange peel remain after
painting, they are removed by rubbing with wet and dry paper. The use of compounds
on the hull is not considered essential; however, if used, a parting agent and
not wax is required.
The
keel flange must be faired to the bottom of the boat using timber strips and
fibre glass in order to form a continuous smooth curve into the fin. The flange
should not be pointed at the leading edge but a little rounded and gradually
tapering for one‑third of the length until a parallel section ensues for
the next one‑third distance, with the remaining one‑third similar
to the leading edge. This section is referred to as "laminar flow."
The keel weight should be minimum (870 pounds); however, with the new minimum
weight requirement there will possibly be a movement toward a maximum weight
with the lightest possible hull.
Keels
are located as far aft as possible while the rudder post should be brought
forward on the bottom in order to reduce the wetted surface by having a shorter
skeg.
The
shape of hulls varies slightly from one builder to another; however, it is
considered that these slight variations are not as important as setting the
sails, mast and fittings to suit the shape being used.
Rounding
of the chine reduces the wetted surface. However, opinions vary greatly on this
point; some have sharp chines in order to give better weather working, while
others meet between these ideas and round the forward two‑thirds of the
chine.
Rig and Fittings
1.
Mast. The mast must be as light as possible, but stiff enough in order that the
mast does not fall off at any one place. Fittings on the mast must be as light
as possible and the spreaders require only a light section, sometimes
laminated, about half an inch thick on the inboard end of an aerofoil section
(curved on top, flat on bottom) narrowing in the middle. A 15" forward
movement of the spreaders is required in order to be clear of the mainsail when
sailing downwind. The control of movement aft is very important and should not
exceed two inches at the outer end.
2.
Boom. A stiff boom is required, of section four inches deep in the centre,
tapering at each end. The section of the boom aft of the main sheet blocks
should be flexible enough to allow the leech to soften in a strong breeze.
3.
Traveller. The traveller is located just aft of the rudder post, since the boat
is wider at this point; hence the traveller track must be equal in length to
the beam of the boat at the point.
4.
Barney post. The main sheet should be located in the boat by a Barney post in
which the top of the block is just below the deck level. The main sheet lock is
located beside the block.
5.
Tiller. Must be as long as practicable (at least up to frame 7), with a tiller
extension always attached.
6.
Runners. The best type of runner is the ratchet type located with the aft end
of the track on the gunwale at frame 6 1/2. Rope lines should not be attached
to the runner slide.
7.
Vang. The circular vang fitting is not favoured as it restricts the movement of
the boom to the square position when running downwind. Without the circular
vang the runner track may be positioned well inboard at the forward end,
thereby reducing the possibility of the runners [backstays] moving to the
forward side of the spreaders when [sailing] downwind The recommended vang
arrangement is a slide about 36" long located on the gunwale from the
shroud plate aft. The vang wire should start at the boom adjacent to the
forward sheet block position, pass through a hook, then to a pulley at the
gooseneck and down to a wheel‑and‑axle type fitting for operation.
The wheel should be about 10" in diameter, and the axle which carries the
vang wire about 1 1/2" in diameter. A light cord is wrapped around the
drum, passes to a pulley on the keelson, then up to a lock at the forward end
of the cockpit hence; the crew lifts up to operate the vang drum. A rubber cord
attached to the vang wire under the deck and stretched to the bow at the other
end will ensure that the slack vang wire will remain tensioned under the boom.
8. Jib
track. With the latest sails, the jib track should be located at an angle of 9E to the centre line at the bow. A second jib
track position for heavier winds is not considered necessary. The length of the
jib track should be approximately 15" in order to have sufficient foot,
leech and pocket of the jib adjustment for all conditions.
9.
Shroud plates. The location of the shroud plates should be such that the cap
shrouds be placed at a point 4" forward of the front of the mast with the
lower shrouds as close as possible behind the cap shrouds. Intermediate shrouds
should terminate at the spreaders and not proceed to the deck level.
10.
Headstay or jumper strut. The jumper strut is considered the better arrangement
since the headstay tends to hold the mast forward and take some load away from
the jib luff. The jumper strut requires very little adjustment.
11.
Sail battens. The sail battens must be straight, reasonably stiff, of full
length and always varnished.
Setting up and Sailing Techniques
The mast must be positioned and raked in the boat such
that a full length boom, when located at the coloured band and lying on the
deck aft, will rest one inch short of transom. The rake of the mast is in the
range of 18" to 30"; however, the best way to obtain the correct rake
is to have the mainsheet operating block to block when tacking on the wind.
The
forestay and runners are first positioned tight, then the cap shrouds tensioned
until the top of the mast is pulled forward and the spreaders are angled
forward (this adjustment made without the runners in their full on position).
With the mast in this reverse bend position the lower shrouds are tensioned.
(This makes certain that the centre of the mast is supported by the lower
shrouds when sailing downwind.) The intermediate shrouds are used to prevent
the upper section of the mast from falling to leeward and should be adjusted to
the correct length by using a turnbuckle above the spreaders. A new length of
wire may then be cut to the required length and replace the length containing
the turnbuckle.
When
sailing the mast must have an even curve over its all length. This is achieved
by the use of (1) the lower backstays and (2) blocks at the deck. The blocks
are added with the runners set until the even bend is obtained, then under sail
the lower runners control the additional bend produced by the mast compression.
The modern mainsail requires a seven to nine inch bend between the top of the
mast and the gooseneck. With the tendency toward mast movement further aft, the
tack at the bow fitting is being moved aft accordingly.
The
traveller setting is normally in the centre in winds up 10 miles per hour, then
movement out in order to keep the gunwale out of the water when on the wind.
Since the traveller position depends so much on the nature of the leech and the
fullness of the sail a set position is difficult to state. The best position is
determined by match racing against another boat, who is leaving his equipment
in a set position, then make adjustments until the boat is moving faster than
the standard boat.
Tell-tales
are very important both upwind and downwind particularly in light air. The best
type of tell‑tale is a length Nylon hose 12" long and 3/4"
wide, located 5 to 6 feet above the deck. A tell‑tale at the top of the
mast is considered unnecessary. The tell‑tale is advantageous when
sailing to windward in order to locate slight wind changes; however, they are
equally as important downwind in order to sail as close possible to a dead
downwind course.
The use
of a compass cannot be under‑estimated since they will quickly indicate a
wind‑shaft particularly when the wind-shaft is a gradual let‑down.
The best location for the compass (where two are being used) is immediately
forward of the helmsman, that is, on the deck just forward of the end of the
runners. The other alternative is hanging under the forward end of the cockpit;
however, this is not considered satisfactory since the skipper must take the
compass bearings. There is a strong tendency for the helmsman to allow the boat
to fall away from the wind when the wind lightens, thereby giving away a lot of
weather position. This tendency is easily checked by the use of a compass.
A
tiller extension is considered essential since it allows the skipper and crew
to move forward, particularly downwind.
When
sailing on the wind the skipper should he just aft of the runner, with one hand
on the runner, while the crew is sufficiently forward to have one hand on the
shroud. When changing from one tack to the other the skipper slides under boom
but over the tiller, thereby not entering the cockpit.
When
sailing downwind the Cunningham eye [a grommet just above the mainsail tack,
Ed.] is raised 6" and the boom outhaul allowed to move inward 4". In
breezes less than 12 miles per hour and sailing on the wind the Cunningham eye
must be raised slightly until horizontal wrinkles appear at the luff and the
boom outhaul allowed to move inward, which produces a tighter leech. Pulling
the Cunningham eye down brings the pocket in the mainsail forward, thereby reducing
the weather helm. When the Cunningham eye is adjusted the jib luff is also
adjusted in proportion to the size of the sails, e.g., 4" up on the
Cunningham eye, then approximately 1" up on the jib luff.
The
runners should be moved forward when sailing downwind, in order to bring the
mast to the vertical position or leaning a little forward in light air. This
allows the pocket in the main to hold its shape and filled with air due to the
tendency of the wind to blow down on the water. When the surface of the water
is irregular it may be necessary to hold the runner by hand in order to tighten
the rig as required or to attach a guide rope from the bow to the mast.
It is
essential when sailing downwind that the lower shrouds be located forward of
the mast at the deck and tight enough to prevent the mast at the spreaders
moving aft and forming a dangerous reverse bend. Should this reverse bend
appear when reaching, the main sheet should be pulled in and the traveller out
at the gunwale in order to tighten the leech and pull the top of the mast aft.
It is
essential when close reaching to let the traveller out before letting the
mainsheet out, in order to keep the sail flat, working, and stretched out.
Letting the sheet out causes the sail to "belly out" with not as
large a surface area exposed to the wind.
Before
the start of a race the crew should sail the boat while the skipper, viewing
under the boom on the leeward side, inspects the jib lead position. The leech
and foot should have equal tension and this is best decided by a look at each,
not by a feel. Since there is a lot of material in the foot of a modern jib,
the "accordion effect" produced must not be confused with too much
tension in the foot.
Sails
It is
recommended that one suit be used for all conditions, since with the latest
fabrics and sailmaking techniques the sails may be varied in shape to suit all
wind velocities.
With a
new sail the pocket should be approximately in the centre of the sail and with
use this pocket moves aft thereby placing a larger strain on the leech. It may
be necessary after one year to (1) have the sailmaker loosen the leech (not
considered advisable since the required adjustment is very small); (2) bend the
mast more to relieve the leech; (3) raise the sail at the boom outhaul fitting
by using a shackle in order to loosen the leech; (4) let the traveller move
away from the normal position. A tight leech can easily act as a "leech
brake," without showing any appreciable change in weather helm or general
appearance of the sail; however, the boat will lose speed. It is necessary to
frequently view the whole leech from the transom any sign of cupping of the
leech to weather or any point where the after section of the sail is not
parallel with the centre line of the boat should be immediately rectified.
The
fastest sails are not necessarily the best looking sails. Leech flutter is not
very important, and in the case of the jib is not to be interpreted as jib
luffing, when sailing close hauled.
It is
essential to have the mast position and the sail pockets in such a position
that the boat has some weather helm and the use of two fingers only on the
tiller pulling to weather is a fair assessment of the required force.
In the
choice of a new sail, between a full and a flat sail, it is considered that the
flatter sail is preferable since as the wind lightens the main should be eased
to allow more draft to form in the sail; also the boom outhaul fitting should
be let in and the Cunningham eye raised.
A high
cut foot on the jib is not desirable, since the lower the cut the larger the
amount of air trapped by the jib; hence when setting the jib at the bow the
clew must be as close as possible to the deck.
Halyard
locks are considered essential for both sails in order to reduce mast
compression.
Sails
should always be folded for storage since the smoothness of dacron is one of
its many advantages. When folding sails it is essential to always fold at the
same points in order to have a regular position for the crease in the sail.
Fresh rater washing of dacron sails is necessary in order to remove salt
deposits which would absorb moisture and make the sail heavier, also the salt
particles cause the surface of the sail to lose its smoothness, thereby
increasing wind resistance.
Racing Techniques and Tactics
Starting. This phase of racing is
vital, since an effective cover at the start in close class racing is all that
is necessary to win the race, hence the advantage of many short races formed
into a series and repeated at regular intervals. It is necessary to test the
starting line in order to select the favoured end. This test is carried out ten
minutes before the start and checked just prior to the start to detect any wind
shift. The boat is brought head to wind at the centre of the starting line;
then when sighting across the thwartship frames of the boat select the end
which is ahead of abeam: this is the favoured end. After selecting the best
starting position, it is suggested that with two minutes to the start move away
but between the starting marks for one minute then return to the line in the
second minute.
Sailing close hauled to weather. The
helmsman concentrates an four items: (1) the main luff, which should start to
luff just before the jib and hence is a handy indication that the jib is about
to luff, (2) the jib luff, (3) the tell‑tale, particularly in light air,
when it quickly records a wind shift; (4) the water and the approach of a
series of waves or chop will require the helmsman to ease the boat a little
away from the wind and move through the disturbance.
Should
horizontal creases appear in the main luff, the Cunningham eye must be pulled
down until they are removed; should angled creases appear the lower runners
must be tightened in order to reduce the mast bend. In the case where a full
sail is being used and the breeze strengthens it is preferable to have some
angled wrinkles in order to have a flatter sail. When strong gusts of wind
prevail the main sheet should not be eased but the boat pinched a little
to weather. In the lighter winds the jib and main sheet should be adjusted
frequently in order to allow for wind changes.
Long
windward tacks are preferable except when there is a sudden "knock"
or it is required to cover the opposition. An effective cover of the opposition
is achieved by staying between the opposition and the weather mark, hence it is
as important to sail against the competition as it is to attempt to sail to the
weather mark by the fastest course. A safe leeward position is obtained when
the bow of the leeward yacht is more than three feet ahead and the leeward
yacht is at no greater distance from the weather yacht than half a boat length.
When boats are approaching on port and starboard tacks the starboard boat
should not automatically use his authority, since the starboard yacht may be on
the favoured wind shift and calling will bring the opposition onto the favoured
tack. This may even require bearing away behind the port tack yacht. When
approaching the weather mark, it is necessary to overstep the mark in order to
keep the opposition covered and in disturbed air. When changing tacks to
weather, look astern in order to observe any S‑trail, which wastes at
least half a boat length of weather position.
Down ‑ wind sailing. This
is not a time for relaxing. The helmsman must sit on the weather side of the
yacht with his weight well forward (hence a tiller extension is essential). The
runners are allowed to move forward allowing the mast to be vertical (or
forward in light airs) and at the same time slackening the forestay, thereby
allowing the jib on the pole to be out further and enable the boat to run a
little by the lee. When overtaking a yacht downwind, it is preferable to
attempt to pass to leeward or if this is not possible run the opposition off
course to weather then jibe, when the opposition will be effectively covered.
Selection and operation of the crew. The
following points should be considered: consistency, alertness, observation,
anticipation, strength, weight, hiking. Teamwork and the crew knowing how to
anticipate the future moves are developed through the basic requirement of
practice. Alertness will frequently prevent equipment failure. Observing the
position of the opposition will require frequent verbal communication with the
helmsman, since it is preferable for the skipper to concentrate more on boat
speed than looking around the course. Where a compass is being used the skipper
should make the observations, not the crew. The crew should attempt to clear
the skipper of as many equipment operations as possible, enabling the helmsman
to concentrate on the work of the tiller only. It is necessary for the helmsman
and crew to hang over the topsides in order to reduce wind resistance and also
improve the moment of the forces. In light airs the crew should be positioned
on the leeward deck.