Race Tuning to Win
by Peter Wormwood
Lets assume that we're going to race your boat in a major regatta. Here's how we're going to tune your boat to win... Reducing weight is the single biggest improvement you can make in your yacht for race performance. So let's take everything out of your Stiletto. Then we'll put back only what's absolutely needed during competition.
For short courses leave out your cushions, berths, battery, extra life jackets (Leave enough for you, your crew and one throw able device), tools and everything else that's not essential.
Be ruthless with weight! After all, Stiletto is the lightest production boat of here size ever built. So take advantage of it and don't heavy it up with unnecessary stuff. Heavy is slow! Light is fast!
Now let's look at your Stiletto's underwater surfaces.. hulls, rudders, and board. Fill in any nicks or dings you might find. Epoxy putty works best. Then, block sand until smooth. If necessary, re-fair board and rudders by sanding diagonally across the grain in both directions. Back the sandpaper with the largest block of wood you can hold. This will remove surface hollows and highs which hinder laminar flow. Paint these items with a light color and wet sand until smooth.
Hardware is next. Clean and lube everything! This way you'll avoid the frustration of hardware that does not work correctly or, worse yet, breaks. Check and lube every assembly including the rudder's internal kick-up mechanism (use heavy grease here).
With the hardware taken care of we'll check the sails. The mainsail is your primary power, so we'll deal with that first. Battens should be put in hard enough so vertical wrinkles don't appear at the batten pockets when the sail is set... this assures proper air flow.
Now set the mainsail, hoist it until you hear the shackle hit the sheave at the top. Then cleat the halyard with enough turns so it is impossible for it to slip. Attach the clew to the outhaul track and lace the downhaul. To set the downhaul, first tightly sheet the main. Then Tighten downhaul as much as possible.
Upwind we'll carry the outhaul all the way aft. It light air we'll have the traveler to weather of center.. about six inches. This allows your sail to set properly without excessive sheet tension. As weather helm develops (or if the hull starts to fly) ease the traveler to leeward until the situation is corrected. At the same time, let's increase mainsheet tension to flatten the sail and tighten the forestay.
In heavy air the mainsail acts like a backstay. Remember this because it's important to keep it as tight as possible while easing the traveler to reduce heeling. In severe conditions I've sailed upwind with the traveler two feet or more to leeward... the tight mainsheet, through the mainsail, is then stabilizing the mast.
The last steps in mainsail and mast tuning are adjusting the diamonds and then the jumper. Make both adjustments in smooth water.
Let's start with the diamonds. Stilettos have rotating masts, so the leeward diamond is loaded rather than the weather diamond. Thus the mast should be tuned so that it is straight athwart ship when sailing, bending only in the fore and aft axis against the jumper. Check this by sighting up the luff groove of the mast. If the mast at the spreaders sags leeward, tighten the turnbuckle. If it bows windward, loosen the turnbuckle.
The procedure goes like this.. Note the condition, then unload the turnbuckle by tacking the boat and make the adjustment. Now on a new tack, note the condition and tack the boat to adjust the other turnbuckle. Repeat the process until you have it right.
Now the jumper stay, remember, this stay is designed to limit mast bend, not prevent it. Adjustment takes some care so you don't hurt the mast. Be sure you pick a day with smooth seas (as in your diamond adjustment) and it's best to have some good air... say, 10 to 15 knots.
Slack off the jumper completely and sail the boat up-wind in the groove... mainsail sheeted properly. Hand tighten the jumper until snug. Next, uncleat sheets to unload the mast and tighten the jumper a few more turns. Our objective here is to bend enough to flatten the mainsail to prevent future bending or pumping when the boat slams into a sea.
The last stage of tuning the rig is head stay turnbuckle tension. Personally I like a very tight rig. You can achieve this by keeping the turnbuckle as snug as possible yet still have the mast rotate freely. In light air this means looser: In heavy air, tighter, never sail with a sloppy rig. It is not safe.)
Jibs are the leading edge flaps for the mainsail. They control the wind that the main sees. The main won't have much to work with if your jib's out of trim. These sails should have their draft about 30-40% aft with an open leech. The most common problem is a tight leech and, luckily, it's the easiest to fix.
Since and over-tight leech closes the slot between the sails, it causes turbulence on the main's backside. You'll correct the problem by adding more luff tension, moving the lead aft, and being cautious about over/trimming.
Set up your headsails so they luff uniformly as you head up. Control this with the location of the jib sheet slide. The further aft, the sooner the top will luff. With a Genoa, the lead should be near the back of the track. Note: keep your Genoa bridle tight so the sail stays near the deck.
Remember, all sails distort with time. Colored sails do this a little faster. If you want to stay very competitive have them replaced when when age or wear sets in. But save those old sails.. use them for cruising and your competition sails will stay completive longer! Keep your sails clean, folded and covered and they'll last much longer.
The Stiletto should be race-ready now. So we'll be discussing boat handling on the course in the next issue. Meanwhile, start preparing yourself and your crew by sailing all you can.