TUNING
TO WIN
By
Lowell North
(Starlights,
June-July, 1967)
There is no way to circumvent the
problems in getting best out of a Star. The matter of boatspeed must be met
head on with a discussion of travellers, Barber haulers, downhauls and so on.
So in an attempt to take up the challenge in a logical way let's begin with the
weather leg and start at the bow of the boat.
Many Stars these days have an
adjustment for the tack of the jib. It can be moved forward or aft, plus or
minus two inches, from the standard spot. In light and medium air we sail the
tack fitting at the maximum aft position. In harder winds we move it forward
for two reasons: (1) when pulling hard on the sheet in strong winds the leech
of the jib will hit the spreader; by moving the tack forward the leech stays
clear of the spreader, and (2) we have a suspicion the boat is faster with the
jib forward as weather helm is reduced and the boat balances better.
However, in extremely heavy air
(over 30 m.p.h.) the situation reverses and the boat develops lee helm. But we
don't normally try to adjust for this as the condition usually arises suddenly
and we simply try to trim the sails to allow for it. Frankly, I am not too good
at this. In the 1966 World Championships at Kiel, Germany, in which Finn sailor
Peter Barrett crewed with me, we did not seem to have really good speed to
weather when the wind was blowing over 30 m.p.h. (which it did too often). It
was in the 20 to 30 stuff, just before the lee helm came on, that the boat seemed
to be tuned about right.
The best way to alleviate lee helm
in the extremely heavy air is to switch to a smaller, flatter jib.
In the Worlds at Kiel we found the
most important adjustment on the jib was the "Barber hauler." This
device was invented by the Barber twins, San Diego Lightning sailors, and is
simply a lanyard with a fairlead on the end of it through which the jib sheet
passes forward of the normal jib lead. The lanyard leads through the deck out
near the gunwale and is controlled from below the deck. With the Barber hauler
the lateral position of the jib lead can be accurately controlled and easily
adjusted.
In smooth water and light winds we
sail with about a 10 degree angle on the jib lead. As the water gets rough, and
particularly if the wind velocity increases, we begin to move the leads
outboard. At about 12 to 15 m.p.h. the angle is 11 degrees, at 18 to 20 the
angle is 12 degrees, and at 25 to 35 it is out to 13 or 14 degrees. We also do
a bit of fore and aft adjusting on the jib sheets, but not as much as in and
out. In really light air our leads are about three inches forward of where they
are in heavy air. We generally move the lead a little bit forward of the normal
spot in very light airs, back to the standard position for most weather, and a
little bit further aft in extremely heavy weather.
It is interesting to note that with
the low‑cut jib, which has a clew about six inches lower than the
standard jibs we used the year before, we had better results with the sail
trimmed about one inch further outboard. The correct jib trim is difficult lo
determine, but a good rule of thumb is to trim it so that the middle batten is
parallel to the center line of the boat. In smooth water you can trim a little
tighter than this and in rough water not quite so tight.
The luffs of Star jibs are made
adjustable these days in one of two ways. One is the sliding tack arrangement
developed by Dick Stearns, and the other is what we call the sleeve jib where
the jib stay is fed through the tape in the luff of the jib. In either case the
tension in the luff of the jib is adjusted either by downhauling at the tack
or, in the case of the sleeve lib either from the tack or by the halyard.
As materials change and stretch less
less adjustment is required. These days probably one inch adjustment is as much
as we use going to windward. It is better to think of it as stretching the luff
just enough to compensate for the extra leech stretch that occurs from heavy
winds and trimming hard. This keeps the jib in balance. Another adjustment that
will effect the shape of the jib is the tension on the backstays on a Starboat.
By slacking the backstays you can change the shape of the jib. This affects
different jibs in different ways. Generally speaking in light air it is better
to slack the backstay so the jib luff can sag.
We have found it best on the
Starboat to stick to one mainsail. And it is probably true that the best
sailors also stick to one jib, with the possible exception of a small, very
flat jib for extremely hard winds. At the 1966 World's and European
Championships we measured in just one mainsail but we measured in three jibs.
We used the same jib in all of the races except when we used an older, smaller,
very flat jib when it was blowing quite hard (although this was not the
heaviest race). The one time we did use the smaller jib we found our speed
about the same as it had been in similar breezes with the larger, fuller sail;
but we might well have been better off the day it blew steadily at over 30
m.p.h. to have been using the little flat one.
Far more can be done to change the
shape of the mainsail than the jib. The bend in the mast, the tension on the
luff the tension on the foot, traveller position and the trim of the sheet are
the basic adjustments. The bend in the mast is the most difficult and the most
critical. The sailmaker usually has instructions on the amount of mast bend the
sail is to be cut for and the skipper will begin from there, trying always to
increase his knowledge of sail shape so that he can get the best out of his
mast‑sail combination at all times.
Because of the lower stretch in
dacron in the past few years the change in bend from light winds to heavy is
much less than it used to be. Four or five years ago we had our mast straight in
light winds and had an 18‑inch bend (chord depth of bend measured at the
center of the mast) in heavy air.
Now we are using a six‑inch
bend in light airs and an 11‑inch bend in hard winds. In other words
there is less than one-third as much difference from light air to heavy air
bend. Of course different sails require different types of bend. Our Star sail
currently requires more bend at the top of the mast and less at the bottom,
which is not unusual. One reason for not having too much bend down low is to
keep the spreader from pushing forward into the leech of the jib.
Besides the fore and aft bend in the
mast the sideways bend will also effect the shape of the sail and the way the
boat performs. By holding the mast to windward down low, for instance, you can
open up the slot between the jib and main and reduce backwind. As yet no one
has been notably successful in the Star class with extreme sideways bend. This
is in contrast to recent form in other classes - Snipe, Flying Dutchman,
International 14 - where sideways bend is considered desirable.
With our present Star rig, while
bending about 11 inches fore and aft we are bending from two to three inches
sideways. One thing that does seem certain about sideways bend is that
"reverse" curve, where the tip of the mast is further to windward
than the middle, is definitely not good. On a Star the bend comes naturally, so
that the rigging is an attempt to prevent too much bend. The jumpers keep the
top from bending too much, the lower backstays and the blocks at the deck (and
the spreaders in some cases) keep the lower part of the mast from bending too
much. My mast is so limber that I never have to change the wedges at the deck.
It is important to keep the mast wedged tight at the back of the deck partner so
that the spar does not have a tendency to reverse bend when reaching and
running. One of the most common causes of mast failure in Stars is when the top
of the mast bends far forward and the bottom part of the spar kicks aft causing
a break between the deck and the spreaders.
It is easy to overdo the tension on
the luff of the mainsail, whether the adjustment is done by means of the
gooseneck or use of a Cunningham hole, or both. In general the tension should
be just enough to keep distortion wrinkles out of the luff. Care must be taken
especially when the sail is new as there will be a tendency for the draft to be
too far forward then anyway and too much tension on the luff will pull it even
further forward. The draft should be allowed to go back at least to the middle
of the sail.
The outhaul is primarily to control
the fullness of the main and the correct setting for it in various winds will
have to be found by trial and error. Usually in smooth water with the wind at
more than seven or eight m.p.h. the sail should be out to the end of the boom.
On reaches and runs it should be slacked off six to eight inches.
The traveller adjustment is another
variable about which one cannot be dogmatic. Its use will depend on such things
a the roughness of the water, the flexibility of the mast the fullness of the
sail, the weight of the crew, and of course the strength of the wind. Currently
we are sailing with the traveller out further than we used to in winds of six
to eight m.p.h. With this amount of air the traveller is allowed to slide six to
eight inches; in 12 m.p.h. winds we let it off eight or nine inches, in 15
m.p.h., about 12 inches and in 18 m.ph about 15 inches. In even stronger winds
the traveller nigh be allowed out as far as 24 inches, but when the wind gets
up over 30 the traveller must be brought back in and the she eased to keep the
boat from developing lee helm.
A Starboat seems to go best with the
mast raked so that the boom is very close to the deck. This is probably the
most certain thing that can be said about tuning a Star as I have seen no
exception to the rule for some years.
Mainsheet tension is another one of
the "indefinites" in trimming a Starboat, but a good starting point
is to pull until the top batten is parallel to the boom in moderate air. In
light winds it should be trimmed a bit harder than this and in hard weather not
so tight. There should be a very small amount of backwind in the luff of the
main - just a slight lifting near the mast. In very heavy winds it will not be
possible to stick to this "slight lift" and under these conditions we
try to achieve what is known as a "sleeping action," where the sail
carries quite a large, but permanent and steady backwind. The sail should take
on an S shape, but should not flap or shake.
The rigging on a Starboat (and the
same must be true for any sailboat which is to be raced seriously) must be kept
to minimum. This is particularly true for all "perpendicular rigging"
such as shrouds, halyards, jumpers. All above the deck gear must also be kept
as light and as clean as possible. Currently there is a difference of opinion
on how the jumper stay should be arranged on a Star. Most of the top boats for
the last two years have had a V strut arrangement which was developed by Skip
Etchells. This would appear at first glance to be more rigging than is
necessary, but I switched to it because it works easily and gives better
control of the mast head than is possible with a single strut (especially on a
very light spar). The single strut tends to bend off to leeward especially on
the tack where the jib stay and halyard lean against the jumper stay. On a very
light spar this can cause serious problems. The cleanest arrangement of all is
to have the top of the mast unsupported on the forward side - with no headstay
or jumper at all. But this requires a heavier mast and you lose that masthead
control which seems to be so important. Few successful boats have been without
some sort of forward masthead support in recent years.
Next to nothing at all, the cleanest
arrangement would be a single headstay going from the bow to the masthead, but
this system seems to be dropping from favor as most of the top skippers feel
that, like the single jumper, it does not give sufficient control over the tip
of the mast.
The jumper wires on my boat are
solid 072 wire; whereas the rest of the rigging is 1 by 19. The upper and
intermediate shrouds are 1/16, the lower intermediates (from spreader tip to
deck) are 3/32 and the lower shrouds are 1/8. Quite a few of the European boats
(and a growing number of American boats too) are now using solid rigging all
the way through. My jibstay is 1/8, and as mentioned earlier the jibstay is fed
through the sleeve of the jib, but a recent rule change requires that the
jibstay be kept outside the jib, so now when this system is used it is
necessary to have two jibstays, one that feeds through the jib and one that
remains outside to meet the rule. The extra stay is still valuable, however, as
it serves to pull the mast forward on a run to keep it from slopping around when
the backstay is eased to straighten the mast up.
The main halyard lock is
conventional on the outside of the mast and the halyard is left loose down the
front of the spar. It would be better to have some clips or something to keep
it stowed neatly out of the wind, but nobody seems to bother about that.
Boats with very light spars have to
carry backstays from the top of the mast to avoid losing the spar when broad
reaching and running in strong winds. We added these after the first race in
Kiel after we nearly lost our mast on the final leg.
One‑sixteenth wires were
fastened to the top of the mast and led down the after side, taped to the spar
every few feet lo keep them out of the way except when brought into use on the
final run to the finish. Then we led a 1/4‑inch dacron line up through
the after deck just aft of the rudder post. This had a simple, but strong,
snaphook on it. When we rounded the weather mark for the last time Pete would
reach forward and pull the backstay away from the mast, handing it back to me,
I would clip the end of the rope to the thimble on the end of the stay, and
that was it. It probably took less than five seconds to set up. If necessary it
could be adjusted on a cleat to the keel near the aft end of the cockpit.
Another system often used is a
1/16th wire which is hoisted with the halyard, being fastened just above the
headboard of the mainsail. These come down and fasten to the regular backstays
about two feet above the deck.
Now that Stars have a minimum weight
of 1460 pounds there is no need for superlight hull construction and in many of
the recently built boats it is possible to add 10 to 20 pounds of fancy gadgets
below decks. At Kiel my boat weighed in at exactly 1460.
There are certain tolerances in the
lines of a Starboat, so that boats are not exactly alike. In past years boats
have been built different ways by different builders and there has been a
tendency to think that it was necessary to have a new boat every year or two to
remain competitive. Perhaps in years gone by there was some truth in this, but
I sincerely believe now that enough development work has been done on Star
hulls that if you can find a reasonably new and competitive hull it will not be
outdesigned in the next few years. My boat was completed in March, 1963. and I
believe it is as competitive as any in the world. I have no intention of buying
a new one for a few years, and when I do it will undoubtedly be fiberglass.
As far as hull finish is concerned I
am a believer in the sanded surfaces - about No. 400 wet and dry, or a little
finer.
My cockpit and deck layout are
reasonably standard, with the exception of the console in the center of the
cockpit, taking the place of the normal barney post. This is, in effect, a
large barney post and instead of just having the mainsheet attached to it I
have the mainsheet traveller control, the jumper stay control and the
Cunningham hole line. This seems handier than having these lines on cleats at
the side of the cockpit and it keeps them out of the way of the whisker pole
when it is being stowed.
There is a Com‑tek type pump
down in each chine, and in the hard going at Kiel they were invaluable. I think
it is an advantage to have the boat nearly dry when you approach the weather
mark so it can jump up onto a plane a little quicker. We also have an Elvstrom
suction bailer on each side.
In summing up I would point out that
there is plenty to keep two people busy on a Starboat and it is the many‑sided
tuning problem that makes this the most satisfying and rewarding class in which
I have ever competed.