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.