written by Matias Collins on January 1 of 2001 and read by 1907
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SAIL TRIM WITH THE V-1 JIB
Controls
- Fullness
- Jibstay Sag
- Shroud Car Position
- Mainsheet Tension
- Backstay Tension
- Crew Hole
- Luff Position
Jib Lead Angle - Vert. and Horiz.
Sheet Tension
Vertical Draft Location
Clew Hole and Luff Position
Sheet Tension
Horizontal Draft Location Jibstay Sag
Luff Tension
Openness - Clew Hole and Luff Position
Sheet Tension
When Dave was asked to look over the above outline of factors determining jib shape, he said that I was making it much too complicated, that he didn't think about draft position and fullness, never went down to leeward to look at his jib! Fie felt that (inasmuch as sailmakers had designed the jib to work in a pre-determined environment) all the sailor had to do was to adjust properly all of the factors that affected jib shape and the correct jib shape would logically follow! (I put an exclamation mark there because this was a surprise to me.)
1. Intent - The intent of V-1 (and other) jib trim is to retain the designed shape. The trimmer should do his best - despite alterations in aerodynamic force, jibstay sag, jibstay movement, etc., etc. - to keep the sail - in all wind strengths and all conditions - the same (with minimal variations). The horizontal draft position should be about 40% aft of the luff -but Curtis never looks to check it. The designed luff curve of a V-1 jib is about 1 1/2-2 inches and it should be set on a forestay that only sags about 3-4 inches. That 3-4 inches must be induced in light air and must be minimized (prevented from increasing) in heavy air - and control of jibstay sag is the most important factor determining proper trim (but it should be attained through proper mast control.
Standard Settings -
Traveller - Set car (wire) 11"" (from centreline on splash rail)
Clew Hole (from back corner) #2 or #3 (new jib #2 - old #3)
Luff position (tack from deck) 3"" (with luff showing wrinkles) (all adjustments at tack)
Vertical distribution of draft should be (as sail was designed) fuller at the bottom but not excessively
2. Adjustment (to retain same shape) - Jibstay Sag
Mainsheet - until 6 knots mainsheet alone controls jibstay
0-3 knots - no tension
3-6 knots - great increase in tension
Backstay - 0-6 knots - enough tension to produce 1 1/2-2"" of mast bend
6-8+ knots - add backstay tension to keep jibstay sag at 3-4""
Upper shroud cars
0-6 knots - #1 position
6-10 knots - #2 position (one sitting on deck)
10-14 knots - #3 position (one hiking)
14-20 knots - #4 position 20+ knots -
#5 position Tack position - Gradually tension - full down at 14 knots to keep draft forward and open top
Jibsheet tension Gradually increase tension but under 8-10 knots never stall upper leech tell-tales
1. Mainsail (If properly adjusted jibstay sag will be appropriate)
Mainsheet tension- err on keeping too tight with too little backstay
0-3 knots - raise boom to reduce leech tension
3-6 knots - increase mainsheet tension with leech telltales flowing
6-14 knots- tension (once up to speed) sufficiently to stall tell-tales while main is kept full and jibstay tight by shifting shroud cars aft #1-#2-//3
Backstay - primary control for variations in velocity err on being overpowered - tension backstay only when overpowered avoid being underpowered - ease backstay, then mainsheet
14-20 knots - shrouds cars aft #4
backstay progressively tighter
mainsheet to keep leech firm tell-tales just flowing "Minimal backstay" -find tension that with shroud cars #1
begins to add additional mast bend - and add a little more - should always have tension
DC-1 main (leech tighter) requires more backstay tension than ES-11.
CURTIS ON HEAVY WEATHER
Excerpts from an Interview published in "SAIL MAGAZINE"
Setting up the boat
Curtis demarcates 15 knots of wind as the point above which you have to concern yourself with controlling the rig, especially the forestay tension and the mainsail shape. The trick is to increase the former while maintaining the latter.
Pulling the upper shroud aft on the track puts tension on the spreader tips and inhibits bending at the spreaders. The lower shroud tracks are sloped downward and aft more than the uppers. As the shrouds are pulled aft, they get tighter, acting like running backstays and keeping the mast straight.
"Moving all the shrouds back," says Curtis, "really stiffens the lower part of the mast and allows you to pull all that much harder on the backstay to control the forestay. When it's blowing, you tighten the backstay until the mainsail won't allow any more bend and starts to turn inside out. From that point you add heaping doses of main-sheet tension and lots of cunningham to get a solid rig and a pretty flat mainsail. We're trying to get the forestay to give as little as possible, but we're lucky if we can get the sag down to six inches.
In winds over 22 knots, Curtis also tightens the vang, which bends the mast down low and flattens the mainsail a bit more. More important, it moves the mainsail's centre of effort forward an inch or so, which reduces weather helm. ""Out there today [during the practice race] in 22 knots, I had less helm than if it were blowing five or ten knots, he said.
For San Francisco Bay's notorious short chop, Curtis likes to keep some twist in the mainsail leech. As the bow rises on a wave, the apparent wind slows, especially at the head of the sail, only to speed up as the bow drops down the back of the wave. Keeping the leech twisted assures that some part of it will always be in correct alignment with the wind.
You get twist by pulling the traveller to the centreline, pulling on the backstay to bend the tip of the mast, and letting the upper leech fall away as much as 18 inches. You also ease the mainsheet a bit, which seems to contradict Curtis's previous advice. ""It gets to be a real hunt-and-peck to find the right combination of vang, backstay, mainsheet, and shroud tension so everything is balanced for the wind and chop, Curtis admits.
Aside from the forestay, the only other significant heavy-air adjustment that Curtis bothers with is the jib car. In puffs, he has the crew let the jib out on its athwartship track to open up the slot between main and jib and reduce the backwind effort of the forward sail.
On a long running leg in heavy air, Curtis says, it pays to let the mast return to vertical to get the chute out in front of the boat. In order to do so, you have to return the shroud cars to their forward position, at least on one side. Curtis prefers to release the portside cars, because if everybody forgets to re-position them during the takedown, it's easy to pull them back after you round up to the new beat on port track.
It also pays to manually tighten the turnbuckles of the lower shrouds when you're racing a breeze. If you can get them tighter than the uppers, they'll pull the middle of the mast to weather and let the upper portion of the mast fall off to leeward, thereby depowering the rig even more.
Sailing on Olympic course
On the weather leg, timing your tacks to occur in smooth water should be a priority, unless tactics or an emergency forces you to do otherwise. ""it's really slow to get slammed by a wave in the middle of a tack and be stopped,"" says Curtis.
Soling crews wear ankle hobbles - straps around each ankle that are hooked onto a ring in the boat. The hobbles take the place of hiking straps but make it hard to shift weight around much on a beat, especially when the two crew members are slung over the side. In a blow these two crew should let off their body harnesses until their backs are parallel to the deck and as close as possible to the water. The skipper can't mini-hike as the crew does. Instead, he should droop-hike over the rail with his head up to see the waves and wind. The crew should still be able to see and call the compass headings and direct the skipper in close tacking manoeuvres, since they're at water level and can see under the boom to leeward.
Curtis normally sails with a crew weight of about 570 pounds, with his two crew weighing about 200 pounds each. With Billingham, Curtis had about 630 pounds on the rail, which is rare but effective in heavy air. Ideally, the middle man should be the heaviest and the skipper the smallest
The initial set
Unlike most other Soling sailors, Curtis stores his spinnaker pole on deck for the first beat. He figures he saves a couple of seconds over those who store it on the boom and have to pull it forward and attach the guy. Instead, forward man Brad Dellenbaugh clips the guy into the outboard end and anchors the inboard end on the outer-most starboard jib traveller support. The pole is held in place by tightening the sheets. The topping lift is attached to the pole and led outside of the jib track to keep it clear of the jib.
Good Soling sailors wait until they're about ten seconds from the mark to raise the pole and prepare to hoist. In heavy air you want to keep your weight out as long as possible. The mechanics of hoisting are the same as in lighter air, but special emphasis needs to be put on pulling the guy forward and getting the halyard up as soon as the rolled chute is thrown out of the cockpit.
"If the sheets twist and the chute fills, you're cooked," warns Curtis, "because the wrap is in the sheets, not the sail. I have the guy in my hand, and the second I see the spinnaker leave the crew's hand, I pull it to the pole and around the headstay. The forward crew is hauling as fast as he can on the halyard at the same time.""
On heavy-air reaches, you have to release the leeward twing all the way so the sheet can clear the outer end of the boom at the hoist and ride up the leech of the mainsail. If it doesn't, you've got to pull in the boom by hand and flip the sheet over. This frees up the spinnaker leech, reducing heeling pressure. It also allows you to release the boom if you start to broach.
Soling class rules permit pumping the guy as much as needed to prevent broaching if such conditions exist. The forward crew reaches up and yanks on the guy, which brings the pole rapidly down and aft, opening the leech, and freeing the pressure on the rudder.
The key to going fast on a heavy-air reach is trimming the chute correctly. You have to let the sheet out as the boat rises up to the front of a wave and the apparent wind moves aft. As soon as you accelerate, trim the sheet back in. ""If you're not strong enough to let that two feet of sheet out and trim it back in,"" says middleman Bob Billingham, ""you just can't sail a competitive reach. You've got to always be on the edge.""
Curtis and his crew move aft on a power reach and hike straight legged (to keep their bodies out of the water). The forward crew grabs the guy for support, and the middle crew has the spinnaker sheet. The skipper pumps the main. Curtis likes to have the vang control line at his fingertips rather than leaving the vang to the forward crew and distracting him from playing the guy. He also eases the backstay a few inches, releasing the mast but keeping the forestay fairly tight, which helps the jib hold its shape
Managing the gybe
Ideally, you want to catch a wave going into the gybe at the reaching mark. This will reduce the pressure on the rig. Often, however, tactics deem otherwise. Use your leeward twing line to pull the spinnaker sheet down so the forward crew can grab it after the boom comes across and hook the pole to it. The easiest place to mess up during the gybe is when the boom is halfway across the boat and a puff hits.
During the practice race before the North Americans, Curtis lost his footing during a gybe. He ended up with his feet hobbled together and up under the deck, where he couldn't get any traction. The boat rolled violently to weather, much to the amusement of his competitors. ""There's a fine line between being in control and being totally out of it,"" he said afterward with a chuckle.
At the leeward mark, the chute is almost always dropped to weather. By doing so, you can pack it in the port spinnaker bin and be ready for the set at the next weather mark. Only if you're approaching fast on a tight reach would you drop to leeward. So his crew doesn't waste time in the boat setting up the pole on deck, Curtis stores the pole on the boom for the remaining weather legs.
The cardinal rule for coming out of the leeward mark is not to tack onto starboard for at least 100 yards. On a spinnaker reach, Solings kick up a huge bow wave. ""Even if you tack around the mark and you're above the boats coming in,"" warns Curtis, ""you're going through the horrendous backwash. You've got to find a smooth-water lane as well as a good wind on the second beat.Running
Setting up for the running leg in heavy air requires a few more adjustments. The mast has to let forward, which means releasing tension on the shrouds by moving the shroud cars forward on at least one side. You also want your twing lines set to keep the leeward sheet under the boom, which allows the spinnaker to shift out to weather and gain more exposure. Heeling to weather is fast, but again there's a razor's edge between fast and crashing to weather. Don't heel the boat more than 15 to 20 degrees. With a heel more than that the boat will be harder to steer and the bow will want to round down.
Watch your crew-weight placement fore and aft, too. In general, Curtis says, you should stay forward in the cockpit on a run to get the stern out of the water and decrease drag. This is less important in heavy weather, however, than keeping the bow from nosing into the waves. As you start down a wave, the crew should stay forward to help angle the boat down that wave. if the bow starts to poke into the next wave and the helmsman can't wriggle the boat free by heading up or down, shift your crew weight aft or you will have solid water coming into the cockpit. Needless to say, this not only affects your concentration but it's also very slow.
Gaining the edge
While medium-air racing tends to maximize tactics, light and heavy-air conditions tend to emphasize speed, not only in a straight line, but at the corners as well. Achieving that speed depends on setting the boat up correctly and executing manoeuvres with authority. ""1 put a priority on boathandling in heavy air,"" says Curtis. ""Once you have that confidence, you can concentrate on tactics and windshifts.
MELGES ON ...
report on a seminar conducted by BUDDY MELGES
On learning and practice
Spend more time practicing and studying your sails and the other fast boats' sails than you have been. Before the last Olympic trials, Buddy and his crew sailed three days a week in all types of weather on Wisconsin's Lake Geneva. There were no other Solings, but they often took out a powerboat so that they could get off their boat to study their sails. They sailed throughout the year and, on some days in the depths of winter, sailed iceboats on the frozen part of the lake and the Soling later on open water at the other end of the lake. They put themselves through all sods of simulated race situations, and eventually they were able to sail with almost no commands needed during tacks, jibes or normal sail. Buddy emphasises the importance of looking at your sail from outside the boat. He feels that there are important attributes of sails that are virtually impossible to study adequately from inside the boat, in addition, he is obviously very flexible and willing to learn from his competition. He once sat out a Soling World Championship and just watched how the best helmsmen handled their boats and set their sails.
On experience
He attributes a lot of his success to his extensive experience in high-speed boats on inland lakes. Melges, like EIvstrom, does not depend heavily on compasses relying instead on his ability to read the shifts off the water to windward. Practice on Lake Geneva helped develop this skill. ""Back on Lake Geneva," he said, "we think compasses are for hunting."
On hull preparation
Buy from the leading builder in your class. Arrange the controls so that they are right where you want them, and neither you nor your crew need dived your attention to use them. Carefully prepare the underwater surface so that you know they are the best possible. He fairs the bottom of his glass Soling using sandpaper on a three-eighth-inch-thick foam sanding block, first with 320 wet or dry, then 400, 500, 600, DuPont hand rubbing compound and, finally a fluorocarbon spray. I saw him devoting many hours to the bottom of his boat at the Kiel Olympics. In addition to providing a flawless finish, Buddy seems to be trying to ""one-up"" his competitors with his attention to his boat and to use the activity to release his own reservoir of excess energy
On sails
Look at the sail from all angles, both off and on your boat. Looking up at the main from under the boom is helpful. The angle that the top batten makes to the boom provides a good guide to leech tension. The vang is more critical to boat speed to windward than downwind (on a Soling). Leech setting depends most on the sea condition. In smooth water, little twist is best. In chop, the leech should be eased to allow lots of twist. Sheets can be eased and the traveller brought to windward of the centre line to achieve this. He is of the opinion that twist helps reduce pitching moment by reducing drive high up in the sail. The same considerations apply to the jib - a twisted leech being best in a sloppy sea, and a tight leech in smooth water
windward legs
Bunch crew weight fore and aft. He looks at the horizon as he sails, judging the angle of the forestay to the horizon. He sails a scalloped, ""gyrating"" course, up and then off again. When there are waves, he heads up while the bow is rising on a wave, then bears off just as the crest passes under the boat and sails off as the bow goes down the back of the waves. Heading off just at the moment that the crest is under the middle of the boat minimises the resistance associated with bearing off since both ends of the boat are, relatively speaking, out of the water, if a competitor is nearby, try to point highest whenever he looks over at you.
downward legs
Spread crew weight fore and aft when riding down waves. Buddy often stands up, studies the yarns on the weather shroud and holds one or both of his spinnaker sheets. He stresses the importance of playing shifts and seeking the best angle to the apparent wind at which to jibe downwind. To windward, you tack on the headers and to leeward you jibe on the lifts. Just as on a weather leg don't go way out to one side, but play the shifts down the middle. Don't change course sharply as that always costs you distance. To check that your course angle to the dead downwind line is a good one, sail 100 yards or so off that line, then jibe and come back to it. At this point see if you have gained on the other boats. Buddy doesn't remember the last time he was in a ""dog fight"" (luffing duel), but he always tries to arrange his downward tactics so that the other boats are likely to stay bunched or luff one another. He uses aggressive tactics and tries to jam the fleet together so that they will interfere with each other.
wind sail trim
The main should be baggy with mast raked forward if possible. A small flat spinnaker often pays off in winds under 4 knots. By all means maintain flow across the spinnaker. ""Ventilate"" the chute and don't let the air in it become ""constipated"" due to a tight leech. When the wind is over 12 knots, start to play the waves. On a run in these conditions, heel the boat to windward and ""skid"" it downwind. ""If the spinnaker is not dancing, it's overtrimmed."" If the spinnaker luff is uncontrollable (i.e., normal trimming does not prevent its collapsing) lower your pole until it becomes controllable. On reaches a properly cut spinnaker requires that the pole be set at right angles to the headstay. In heavy air when you are about to broach, pump the helm to ""give the water back to the rudder"" and prevent the rudder from stalling, and ease the vang to free the leech. In winds over 18 knots, he sets his small chute.
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