This paper was prepared by Bob Spraker some months ago to help the PMYC sailors improve their Victoria tuning skills.
Mast base position on the deck controls the center of effort fore & aft. Moving the mast aft brings the center of effort aft, thus increasing weather helm. If you have a movable mast, adjust it aft for light air and move forward as wind increases. I will move the base 1” forward of the “standard” Vic mounting hole in heavy (20+ mph) air, standard position in medium and as far back to the keel bolt in light. This is a lot of work and can take time. I usually do a “garage setting” at home, based on the days forecast and usually don’t move it during regatta day. If your mast is not movable, use the standard Vic mounting hole as default. You can control the center of effort pretty well with mast rake just using standard mast position.
Forestay – This controls mast rake; very important. The amount of mast rake and mast position controls the amount of weather helm. Raking mast aft in light winds for a slight weather helm is desirable. As the wind increases so does weather helm. Reduce rake with increased winds; going as far as mast forward in strong winds. I usually don’t rake the mast as much as most skippers in light air, but rake forward more in heavy air.
Halyard – Jib halyard tension sets the amount of curvature in the luff AND the draft position. The tighter the halyard, the less curvature in the luff. I typical like a draft position of 40% aft of the luff; this should be your default position. Set the tension based on wind and wave conditions to be more precise. More curvature moves the draft forward which gives more power, but reduces pointablity. Stronger wind conditions push the draft aft, so increase tension as wind increases. The choppier the water, the more curvature you need forward to punch through waves. Also, some curvature forward is needed for power in light winds. With medium wind and flat water, less curvature gives better pointing and better upwind VMG. Less curvature gives better pointability, but is harder to steer/control. Use halyard tension to set draft position based on wave conditions, wind speed and your steering ability. I usually set the halyard to have a “little slack” as compared to the forestay.
Topping Lift – The topping lift controls the amount of leach tension and twist in the jib. As wind increases, the backstay needs to be tightened to control forestay sag. As backstay tension is increased, jib leach is tightened, thus reducing jib twist and closing down the slot. Offset increased backstay tension by increasing the amount of topping lift tension to maintain twist and an open slot. Note: when there is a lot of wind speed variability, I use a little more backstay AND more topping lift tension.
Outhaul – Jib outhaul controls the amount of camber in the sail (not draft position). Typical jib camber is between ½ and ¾ inches; less with very strong wind. I typically sail with 5/8” of camber in the jib and set draft position (with halyard) based on waves and wind. A little more camber and forward curvature in light and choppy conditions and less camber and less forward curvature in stronger winds. In heavy winds, I set the camber as low as ¼”.
Sheet – The jib sheet setting dictates the angle sailed close-hauled. I mark my deck at 10, 15 and 20 degrees. I use 20 degrees in light air as a normal setting and work in tighter as the wind picks up. 15-17 degrees for medium air and as close as 12 in heavy air. You can pinch up to 10 degrees to make a mark, etc., but that is not good VGM. Jib sheet and main sheet angles need to be coordinated however. I use up to an 8-10 degree differential in medium/light air (4-8 mph) and less as wind increases. Main sheet angle is 12-14 for light, 8-10 medium and 12-18 for heavy. As the boat gets over powered in heavy wind, I back wind the main by sheeting out to the same angle and then some as compared to the jib. For instance, in 20+ mph wind, the jib angle may be 12 degrees with the main at 16. Windward then, you are basically sailing on the jib, with just a little main drawing.
Deck Pivot – Determines jib boom height and pivot point. Many boats have an adjustable jib pivot position which you can use. I personally have found that a fixed position works just fine. I typically locate the pivot 3” aft of the bow. Technically, I would move it back to 3.5” with the mast step aft and as close as 2.5” when the mast is forward in heavy air, but this seems to make very little difference. Jib boom height is a different matter. In light air I believe it is best to have the jib boom somewhat off the deck, up to 1.5”. But more importantly, I want the jib boom to be a minimum of 1.0” BELOW the main boom. This is due to “up wash” from the jib to the main. You want all the air from the jib to be directed around the main. In heavy air, I want the jib boom (& main) to be as close to the deck as possible to lower the center of effort. This reduces heel & the dreaded “big round-up”. I usually just keep the jib boom low, about ½” – ¾” off the deck at the pivot point.
Backstay – I include the backstay under the main because it is aft, but it really has more influence on the jib than main. I start with a “just taught” backstay in light wind and increase tension as the wind increases. As you increase tension, you open the leach of the main, so increased vane tension is needed.
Halyard – The main halyard sets the draft position in the main. I like the draft to be about 30-35% aft. In light air I have a loose halyard for forward draft and to eliminate the “bubble” in the mainsail when off the wind. Tighten the halyard as air increases.
Outhaul – This sets the main camber. A good average setting is 1.5”. I use a little less on very light days and increase as the wind picks up to the 1.5” setting around 4 mph. Medium air (5 – 10 mph), about 1.25” – 1.5” and reduce as air increases. In 20+ air, I have the foot almost flat.
Vang – Along with the backstay, this is the adjustment I use most during a regatta. Once you set the mast rake position with the forestay, I use the backstay and vang to set the main leach tension (twist) for the current wind conditions. I like a lot of twist in all conditions as compared to most skippers. Twist is hard to judge, but to put a number on it, I would say 10 – 15 degrees off the foot. I like quite a lot of twist in light air (15 degrees+) and reduce as wind picks up. Minimum twist is in the 8 – 12 mph area, but still around (8 – 10 degrees). I then increase main twist as the air gets heavy to “spill” air to reduce heel.
Sheet – We have already discussed the mainsheet and the main boom angle. Default is to have it point to the cockpit side knuckle (about 10 degrees). But more important, main boom angle needs to be coordinated with the jib boom angle as dictated by wind/wave conditions, as discussed above.
Battery Placement – Your battery location can help control fore-aft boat trim. Place your finger just behind the keel fin. I want my boat to be level with the waterline on light days, with more and more aft tilt as the wind increases. On 20+ days, move the battery all the way back to rudder post.