A Scow Tuning Guide

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See also : Sail an A Boat Faster, by Buddy Melges

Mast and shroud set-up

Mast set-up The mast should be set-up so that the aft side of the mast is within 1" of the forward side of the black band. The mast must be forward of the band by rule. The mast should be tuned from the deck up (every A Scow has a dip in one rail so you cannot measure down to the chainplates with the jib halyard). Step mast - hook up headstay and backstays but keep loose. Attach intermediates only, adjust so that mast is centered in the mast well at deck Sight up mast to insure straightness, tighten intermediates evenly to approximately 500 to 600 pounds using a Loos tension gauge. Attach lowers, snug up so mast is straight down low. Attach uppers, tighten evenly to keep mast straight above headstay. Put about 300 pounds on uppers to start. Go sailing, sight up aft side of mast and adjust uppers and lowers only to get a slight sag from the tip to boom— do not change intermediates.

John Galley's new custom carbon swept rig on his new 2001 A Scow. New rig eliminates the need of a backstay and bookim.

Mast Rake

AP sail mast rake setting is 42' 8", measured with tape (pull tape up fastened to the main halyard and measure to aft corner of transom).

Fine tuning the mast rake:

Light air: Mast should be close to vertical when boat is sitting flat in the water.

As the wind builds, rake the mast aft to keep the boat settled-in and driving. If the boat feels "jumpy" or "crabby" rake the mast aft.

Heavy air: The mast should be raked aft so that the mainsheet pulleys trim close to "block to block".

Downwind:

Light to Medium air: the mast should be vertical.

Heavy air: Mast should be vertical with symmetrical spinnakers, with the asymmetrical spinnaker keep the mast rake aft and reach downwind.

Jib Set Up

The jibs should be set up so that they are low to the deck. The foot skirt should curl on the deck In light air. The jib should be set up fairly full down low, as the wind builds you will want to gradually flatten the foot of the jib and twist open the upper leech. The upper leech should have a telltale on the top batten. This tell-tale should always be flowing. To find the correct trim, trim until the telltale stalls and then ease the sheet until it begins flowing— that would be maximum trim.

Jib luff: Just pull the wrinkles out in all conditions. Over tensioning the luff may over stretch the sail.

Jib Track: The maximum inboard position would be even with inboard edge of cockpit. Ease outboard in medium/heavy wind to keep mainsail from backwinding. Set to the maximum outboard setting when reaching and running.

Mainsail Controls

Cunningham:

Light air - None.

Medium air - Pull out wrinkles.

Heavy air - Pull hard to move draft forward and open leech.

Vang

Light air - Loose.

Medium air - Snug to keep boom from skying.

Heavy air - Very firm to vang sheet in puffs.

Outhaul

Light air - pull out vertical wrinkles.

Medium air - Pull out vertical wrinkles, or pull to black band to flatten and depower.

Heavy air - Pull to black band.

Running backstay

Light air - Keep soft to sag headstay and power up the jib.

Medium air - Ease in lulls, pull hard in puffs to depower and flatten jib

Heavy air - Pull very hard to depower and flatten jib

Permanent backstay

Light air - Loose.

Medium air - Loose

Downwind - Put a mark on the backstay or knots in the lines for maximum forward downwind mast position (mast vertical).

Mast Ram

Light air - Allow ram to free float, or ram forward to flatten main if it is too full and round behind mast.

Medium air - Cleat in neutral position to vang against.

Heavy air - Neutral to some aft ram to keep main from turning inside out down low.

Downwind - Sight up mast and make mast straight, ram usually needs to be pulled forward to prevent mast from inverting when backstays are eased.

Traveler

Light air - Pull to windward of centerline approximately 8"-10".

Medium air - Center and work down in puffs to keep boat on her lines.

Heavy air - Work up and down in puffs. Maximum out is at rudder posts.

Sheet

Light air - Twist top batten open, keep top leech telltale flowing.

Medium air - Trim until top telltale stalls half of the time. Or sight back 1/3 of top batten parallel to boom.

Heavy air - Flatten and twist top of main work and work sheet aggressively.

Downwind

Symmetrical

• 0 - 6 knots - Use mid-size runner reacher and induce maximum heel to leeward. Keep pole one foot off headstay and keep constant angle of heel with pressure.
• Over 6 knots - Put up the big one and run deep when you have pressure. Keep maximum heel. Board down 1/4. Main Maximum out. Work pole aft in puffs.
• Jibe the pole - Jibe the pole with two people. Jibe the sheets with two people.

Asymmetricals

• 0 - 6 knots - Use the small asymmetrical. Induce Maximum leeward heel. Take jib down if necessary.
• Over 6 knots - Use the big one. Keep maximum heel, Use 1/3 board. Work the shifts. Work the puffs.

Hoisting asymmetricals

Hoist halyard first, under main and keep sail under control to leeward. At the same time pull out bow sprit.

When ready pull out tack and fill chute. Sometimes it helps to put some 30' or so of the sail in stops or rubber bands to keep it from filling.

Jibing asymmetricals

Always Jibe asymmetricals inside the luff. Use a trimmer on each sheet and one person overhauling new sheet on new leeward side.

Asymmetrical takedowns

The windward take down - Head the boat straight down wind, start Jibing spinnaker and overhaul windward sheet around until clew is at spinnaker bag. Some one must always control foot and call for tack release or it will go straight in the water. The person who releases the halyard must also release tack line and tail them down. The helmsman should steer the boat so as to blow the chute onto the deck.

Leeward take down - The best way to do a leeward takedown is to be able to blow the tack away with a snapshackle and let the chute turn inside out.

For the windwrd and leeward takedowns, experiment with blowing off the tack line while holding the halyard until foot is under control.

Mexican take down - Approach the leeward mark on starboard tack approximately 1.5 boat lengths to windward of buoy. When just shy of port layline Jibe the boat and at the same time trim the chute tight on the port side, as the chute blows into the rig release the halyard and drop the chute on the deck. Keep control of the foot and sail to keep it out of the water, steer under sail, tail tack and halyard lines down. This is the most effective take down if done properly.

Trouble Shooting

Too much windward helm - Remedies: first, make sure ram is not forcing mast aft. Pull on a bit more running backstay. If this doesn't get rid of excessive helm, then rake mast aft. Finally pull up board slightly.

Can't point - Jib car might be too high, or jib is set-up too full down low. Ram too far aft or you have too much running backstay.

Leeward helm downwind - Not enough board

For tuning help, contact the North A Scow experts.