One Design:
Ullman Melges 24
Rig & Sail Tuning Guides

Ullman Melges 24 Tuning Guide

How to optimize power and pointing

This guide will provide you with the basics of tuning a Melges 24. Settings may vary on your sailing style, crew weight and your sailing conditions. We strongly recommend you experiment and find out which settings work best for you.

Ullman Sails are dominating the results at the major Melges 24 regattas, reflecting our commitment to being the world leader in one-design and performance sailing.

The key to Melges 24 sailing is not memorizing this tuning guide, but understanding how the settings affect the boat and how it feels. The goal is to be able to feel that something is wrong and quickly fix the problem to keep your boat moving fast.

The measurements and settings in this guide are ones that we have found to be the fastest for the Melges 24. Since crew and sailing conditions vary, you may find slightly different settings are better for you. Go fast and have fun!

  • Boat Prep & Rig Tuning
  • Jib & Spinnaker Trim
  • Crew
  • Sailing Tips
  • Sail Care & Trim
  •  Printable Guide

Ullman fibre path genoa - Genoa trim techniquesMelges 24 Boat Preparation & Rig Tuning

Your preparation goals should be to ensure that your boat and gear:

  • · Are safe and strong enough not to fail in any conditions.
  • · Present a clean profile to the wind and water.
  • · Allow smooth, easy and hazard-free control of all adjustments.

Hull, Keel, and Rudder

The factory finish on a new Melges 24 requires little attention. The class rules do not allow fairing so just make sure the bottom is clean.

Just like the hull, class rules do not allow fairing of the keel and rudder. The rudder preparation is as simple as keeping it in a cover during travel and making sure it is clean. Since the keel is raised and lowered every time the boat is launched, it can become scratched. It is important to make sure the keel trunk is clean and the plastic shim blocks are sanded smooth so as not to scratch the keel. By using a lubricant such as soap, the keel will raise and lower easier . When trailering the Melges, the keel can move around inside the trunk, which leads to keel damage. To prevent this, insert rags or shims into the trunk from the top to wedge the keel into place so it will not move and tie a line from the top of the keel to the mast step to hold it forward.

Preparing the Rig

The rig requires only a minimum amount of work:

  • · Install a Dinghy Model Windex on the mast crane.
  • · Install a stiff backstay batten on the mast crane.
  • · Tape the ends of the spreaders to protect the spinnaker.
  • · Place black tape marks around the spreaders at 2,4 and 6 to use as a trimming reference marks.
  • · Install a short piece of shockcord around the front of the mast, attached to both lower shrouds 8 inches below the spreaders to prevent the spinnaker halyard from getting caught during the spinnaker set.
  • · Polish the mast with a coat of silicone-based marine wax.

Melges 24 Deck Layout

The class ruels do not allow modifications to the deck layout but there are a few small itmes that will improve your boat handling:

  • · Install a 6" soft batten or piece of poly tubing to prevent the spinnaker sheets from going under the spinnaker pole during outside jibes.
  • · Lubricate the spinnaker pole with a dry Teflon.
  • · Mark the pole extender line for maximum pole extension. Put a stopper knot in the line so when the pole is retracted the thick part of the pole - not the tapered part - is in the pole gasket to prevent water leakage .
  • · Remove the bow running lights so the jib does not snag.
  • · Install a shackle in the sailmaker's eye in the luff wire at the tack in place of the standard single block on the roller drum. The Ullman jib has a block and a cleat on the jib so the jib luff tensioning system is a 4:1 purchase instead of the standard 2:1. Lead the tack line from the sail through the shackle, through the block on the jib, back through the shackle and to the cleat on the jib. This is needed to pull the draft far enough forward in heavy air.
  • · Wind the roller furling drum clockwise so the jib will furl counter clockwise. This will prevent the spinnaker sheets from being furled into the jib.
  • · Install backing plates under the deck for the lifeline stanchions.
  • · Drill out two holes in the jib tracks between each factory hole.
  • · Adjust lifeline tension so they will extend to the maximum class rule of 127mm from the deck when pushed down.
  • · Use tapered Y spinnaker sheets so sheets do not snag on the furled jib during jibes.
  • · Install a carabiner on the boom at the outhaul block to lead the tail of the spinnaker halyard through to prevent the halyard from cleating on the douse.

Tuning the Rig

  • · Remove the main halyard shackle and tie the halyard to a 50-foot tape measure with a figure eight knot through the tape end. Raise the halyard all the way till it is two-blocked.
  • · Measure to the intersection of the hull and the bottom edge of the transom. This measurement is 36’ 6 1\2”. Adjust the length of the jib halyard using the turnbuckle or the Hyfield lever. There needs to be some rig tension when the rake is measured. Set the shrouds on the base setting.
  • · In under 7 knots, crew in the boat, pull the rake forward to 36’ 8” -- remember to loosen the shrouds 12 turns on the uppers and 6 turns on the lowers to get back to the “base” setting.
  • · To center the rig in the boat, measure down from the masthead to the chainplates on both sides of the boat. Tighten or loosen the upper shrouds till this number is the same on both sides.
  • · Tighten the lower shrouds till the middle of the mast is in column with the top of the mast.
  • · Set the rig up for the base set up. The base set up is for 7 to 11 knots. Rig tension is measured with the numbers on the Loos Model B and (PT-2) tension gauge.
  • · The goal for rig tuning is for 1\2” to 1” of leeward sag in light air to power up the main. In medium air, the tighter rig keeps the mast straighter side-to-side and gives more control over headstay sag. In heavy air, a very tight rig allows the backstay and the vang to be pulled on hard to maximize headstay tension.

Melges 24 Rig Settings

Base Settings: 7 to 11 Knots

Upper Shrouds: 20 (16)
Lower Shrouds: Tighten the lowers to 18(15) on the gauge, center the middle of the mast by sighting, then loosen 15 turns; this is base. When sailing upwind with the main trimmed and the crew on the rail, the lowers should be just tight enough to allow 1\2” of leeward mast sag between the black band and the hounds when sighting up the mast track.

Light Air: 0 to 6 Knots

Upper Shrouds: Loosen 6 full turns from base.
Lower Shrouds: Loosen 3 full turns from base.

Moderate Air: 12 to 15 Knots

Upper Shrouds: Tighten 6-12 full turns from base.
Lower Shrouds: Tighten 3-6 full turns from base.

Heavy Air: 16 to 19 Knots

Upper Shrouds: Tighten 18-24 full turns from base.
Lower Shrouds: Tighten 19-20 full turns from base.

Extreme Air: 20+ Knots

Upper Shrouds: Tighten 28 full turns from base.
Lower Shrouds: Tighten 28 full turns from base.

Melges 24 Sail Trim

Once your boat is set up properly, there are three sail adjustments that will affect your boat speed more than any other while sailing to weather. These are mainsheet tension, jib sheet tension and backstay tension. If you feel that you lack speed, there is a 90% chance one of these adjustments is incorrect. By following this trim guide you can spend more time concentrating on tactics while still going fast.

Mainsail Trim

The mainsail on the Melges is quite large and requires constant attention. Experiment with the different controls to learn how they affect the main shape and how they interact with each other.

Top Battens

Tension the top two battens very tight for light to medium conditions to power up the top of the sail. Use medium tension in heavy air to flatten the main. In over 16 knots a stiffer top batten will be faster.


The throttle of the boat! In light air trim the main so the aft 2' of the top batten is parallel to the boom or twisted open 5 to 10 degrees in light air and chop. In medium air sheet the mainsheet really hard to flatten the main and tighten the headstay to improve pointing. The aft 2' of the top batten should be parallel to the boom or hooked to windward 5 degrees till the boat begins to become overpowered. Once the boat begins to become overpowered use the mainsheet to control twist and adjust continuously for speed and stability.


The backstay affects headstay tension and mainsail shape. The backstay is left at its loosest setting till the Melges begins to be overpowered, usually about 12 knots. In medium air, while still traveler sheeting, play the backstay in the puffs and lulls. Remember that when the backstay is pulled on the top of the main twists open so the mainsheet must be trimmed in. More importantly, when the backstay is eased the top of the main will hook to weather, therefore the mainsheet must be eased. In heavy air the backstay should be pulled on hard to tighten the headstay and depower the main. To gain more backstay throw, hook the starboard backstay leg around the motor mount to remove some of the extra length. In light to medium air downwind the backstay can be released all of the way to straighten the mast. In heavy air it is a good idea to leave some backstay on to prevent the mast from breaking.


The traveler controls the angle of attack for the main. The Melges 24 likes to be sailed as flat as possible. Adjusting the traveler is quicker than adjusting the mainsheet in puffy conditions and it allows for a steady headstay tension as opposed to using the mainsheet which changes the headstay tension every time it is adjusted. The goal is to keep the boom on centerline till the boat becomes overpowered. As the breeze increases gradually drop the traveler 2 at a time. Alternate dropping the traveler and pulling on backstay to depower the boat and keep it flat. In heavy wind and wave conditions, center the traveler car, pull on maximum boom vang and play the mainsheet to get over waves and through the puffs. In extreme conditions, main flogging, ease the vang an use the mainsheet. This will twist open the top and allow the bottom of the main to still work.


The vang controls the vertical travel of the boom and induces lower mast bend. In light air, the vang should be completely loose. As the breeze increases and you sheet the main harder, take the slack out of the vang line to keep leech tension if you have to ease the mainsheet in a puff. When it is windy enough to switch to vang sheeting, pull the vang on really hard to flatten the bottom of the main. Downwind, set the vang tension in all wind conditions to keep the top batten parallel to the boom. The vang is an important control so it should always be held in the crew's hand.


The outhaul controls the depth in the lower third of the mainsail. In light air and chop, the outhaul should be eased 1 from the black band. In every other upwind condition the outhaul should be tight, at the black band. Downwind ease the outhaul so the center of the foot is 5 from the boom.


The cunningham controls the fore and aft position of the mainsail draft. In light air, the cunningham is totally eased so there are horizontal luff wrinkles in the sail. In medium wind, tighten the cunningham so the wrinkles are just removed. In heavy air, the backstay tension causes the main draft to move aft so pull the cuninngham on very firm to pull the draft forward. Downwind ease the cunningham totally off.

Jib Trim

Jib Sheet

The Ullman jib comes with a leech telltale sewn on the leech. This telltale makes trimming the jib really easy. In most conditions trim the sheet hard enough so the telltale is just on the verge of stalling. The skipper can see the telltale through the telltale window in the luff of the mainsail. The times it can be stalled and should not be are in really light air, choppy conditions, out of a tack, off the starting line and when ever you feel slow. When it is really windy the telltale will not stall no matter how hard the jib is sheeted. A trick for trimming the last inch when the sheet is loaded is for the trimmer to cleat the jib and then push straight down on the sheet from the windward rail and then pull out the slack through the cleat (Banjo the sheet).

Jib Leads

Try to set the leads so the telltales break evenly. The settings we use are measured from the center of the jib car pin to the back edge of the cabin coaming at deck level. Measure the distances and put marks on the deck. The tracks are usually not in the same place on both sides of the boat so this method makes the leads symmetrical.

  • Light air: 206mm from coaming edge to jib car pin.
  • Medium air: 184mm from coaming edge to jib car pin.
  • Heavy Air: 162mm from coaming edge to jib car pin.

Jib Luff Tension

The jib luff tension works like the cunningham on the mainsail, it controls the fore and aft position of the draft. Be careful not over tighten the jib luff because the Melges has a headstay that sags a lot and this coupled with a tight jib luff will pull the draft too far forward making it hard to point.

  • Light air: Slight wrinkles.
  • Medium air: Slight wrinkles to no wrinkles.
  • Heavy air: No wrinkles to very tight.

Leach Line

Always make sure it is as loose as possible without the leach fluttering. Try to avoid hooking the leach to windward, especially in light air.

Spinnaker Trim

  • Tack Line: Mark the tack line so the crew can duplicate settings.
  • Light Air: Tack to the pole.
  • Medium Air: Eased 1" to 2" to help rotate the spinnaker to windward to sail lower. In extreme choppy conditions pull the tack to the pole to stabilize the spinnaker luff.
  • Heavy Air: Tack to the pole.
  • Spinnaker Sheet: In all conditions play the sheet constantly. Keep about a 6 curl in the luff of the spinnaker. Be extra careful not to overtrim the spinnaker, this is very slow.

Melges 24 Crew Work and Boat Handling Upwind & Downwind

It is important to practice and keep the same core crew on a Melges. The boat rewards smooth and organized teamwork. The goals are for each member to have assigned jobs and stick to them, have everyone involved and to keep maximum weight on the rail as long as possible. Moving from the back of the boat forward we label each position:

  1. Helmsperson
  2. Tactician & Helper
  3. Trimmer
  4. Bow


  • Upwind: Steer. Mainsheet, backstay, traveler adjustment. Dictate cunningham, vang, outhaul, jib sheet and crew weight adjustments.
  • Tacking: Steer. Tack traveler. Ease mainsheet in light and heavy air. Help roll the boat.
  • Weather Mark: Call for normal or late hoist, ease mainsheet, release backstay and call vang trim.
  • Jibe: Steer, throw mainsheet, help roll and check backstay on main leach.
  • Leeward Mark: Pre-set traveler and backstay. Call for jib unfurl and spinnaker douse. Trim main.


  • Upwind: Call tactics and puffs and read compass.
  • Tacking: Roll the boat.
  • Weather Mark: Hike.
  • Jibe: Take spinnaker sheet from trimmer. Ease and make sure sheet is free to run. Roll the boat.
  • Leeward Mark: Release spinnaker halyard. Help gather the spinnaker on the douse.


  • Upwind: Trim jib sheet. Check sail trim and monitor speed and pointing compared to other boats.
  • Tacking: Release old jib sheet, help roll, tack jib and fine tune jib from weather rail.
  • Weather Mark: Help pre-feed tack line. Ease jib 3' and cleat it. Grab spinnaker sheet during hoist and begin trimming.
  • Jibe: Hand sheet to Tactician/Helper and grab lazy sheet. Rapidly trim lazy/new sheet as boat jibes. Help roll and rapidly ease new sheet when spinnaker fills on new jibe.
  • Leeward Mark: Trim jib sheet to unfurl jib. Retract the spinnaker pole. Ease spinnaker sheet during douse. Trim jib sheet around mark from weather rail.


  • Upwind: Call waves and traffic control. Adjust sail controls.
  • Tacking: Roll boat and overhaul old jib sheet.
  • Weather Mark: Extend the spinnaker pole. Feed out spinnaker from bag. Raise the halyard. Furl the jib. Adjust sail controls to downwind marks.
  • Jibe: Pull down and overhaul new sheet on inside jibes. Roll boat.
  • Leeward Mark: Adjust sail controls for upwind. Release jib furler line. Gather spinnaker. Finish stowing spinnaker from weather rail.

Sailing the Boat

Upwind Sail Tips

The Melges is most efficient when sailed as flat as possible. Excessive heel causes leeway which is slow. The skipper must work the helm and the sail controls to keep the boat at a constant angle of heel while the crew hikes as hard as possible. In regards to steering, the Melges should not be pinched unless in heavy air and flat water. As a rule of thumb, err on the footing side to keep the boat moving. In light air, the crew weight should be as low and close together as possible and forward to the shrouds. Promote some leeward heel in super light air. In medium air, the crew is close together from the shroud aft and hiking hard. In heavy air the crew is close together 1' aft of medium air and hiking hard. In light to medium air, the crew should roll tack hard against the lifeline as one team. This will maximize the crew weight to gain maximum roll.


Like upwind, the Melges should be sailed flat. Crew moves side to side to keep the boat flat. The weight should be low and forward while in displacement mode and gradually move aft as the wind increases to promote planing. In extreme conditions, one or two crew may move behind the skipper. In light air, sail a hot angle to keep the boat moving at all times. As the breeze increases, begin to bear off to sail the puffs as low as possible till the boat slows, then head up to regain speed. This should be a constant S course. In planing conditions, sail a hot angle again to promote planing. Once planing bear off till the boat is about to fall off of the plane and then head up again to maintain the plane. The extra distance sailed to plane is easily compensated for by the tremendous gain in speed. In light to medium air, the crew should roll jibe just as roll tacking upwind.

Spinnaker Sets, Jibes & Douses

Setting a Melges 24 Spinnaker

There are two types of sets, in front of the shrouds and aft of the shrouds. They are determined by the type of douse. If a windward or Mexican douse is used the sail is set in front of the shrouds. This is also the preferred setting method for the first set of the race. If a leeward douse is used, then the spinnaker is set aft and around the shrouds.

Jibing a Melges 24 Spinnaker

There are two type of jibes possible with asymmetrical spinnakers, the inside jibe and the outside jibe. The inside jibe is used in medium air and maximum roll jibe conditions and the outside jibe is used in super light conditions and as soon as the water begins to whitecap. The only difference in set up is the sheets need to be long enough to run around outside and in how the tack line is attached. For inside jibes, run the tack line from the pole, over the lazy spinnaker sheet, to the clew of the spinnaker. For outside jibes, simply run the tack line under the lazy spinnaker sheet. After that both jibes are the same, ease the sheet and trim the new one as rapidly as possible.

Dousing a Melges 24 Spinnaker

There are three types of douses, the windward, the Mexican, and the leeward douse. The windward douse is used to douse the spinnaker on the port side when approaching the mark on port to be rounded on port. Well before the mark sail straight downwind and release the sheet while pulling the weather sheet around the headstay and into the boat. Release the halyard, then the pole, then the tack line and stow the spinnaker. The Mexican douse is used to douse the spinnaker on the port side when approaching the mark on starboard to be rounded on port. Overstand the mark slightly so when two boat lengths away you can bear off and jibe. As you are jibing the boat, trim the spinnaker in tight on the port side and do not jibe the spinnaker. As the sail backs into the rig, release the halyard and drop the sail onto the deck. Release the pole and the tack line and stow the spinnaker. The leeward douse is used to douse the spinnaker on the port side when approaching the gate on starboard to be rounded to starboard. Bear off and overtrim the sheet and keep it in. Grab the foot and ease the halyard and gather the spinnaker behind the shrouds,then release the pole, then the tack line and stow.

Melges 24 Sail Care

After each use, wash the sails with fresh water and dry thoroughly. Roll the mainsail from the head down while keeping the battens parallel. If the main will not be used for a while, release the batten tension. If the boat will not be sailed in a while, remove the jib from the boat and remove the luff wire from the jib. Roll the jib from the head down and store in its tube bag. Flake the spinnaker and store in its bag.

Melges 24 Sail Trim Guide

Wind strength in knots 0-6 7-11 12-15 16-19 20+
 Shroud Tension (full turns)
-6 turns 20(16)Loos # +6-12 turns +18-24 turns 28 turns
-3 turns   +3-6 turns +19-20 turns 28 turns
 Jib Leads
 (from cabin to jib car pin)
206mm 184mm 162mm 162mm 155mm
 Jib Luff Tension wrinkles slight wrinkles no wrinkles tight max tight
 Main Cunningham wrinkles wrinkles slight wrinkles no wrinkles tight
 (inches from band)
1 tight tight tight tight
 Upwind Vang Tension loose loose medium max tight slight ease
 Traveler (distance
 below centerline)
center boom 0-6" 0-1' 2' center car
 Backstay loose loose medium max max
 Spinnaker Tack Line tight eased 1"-2" tight tight tight
 Jibe Type inside inside inside inside outside

Please feel free to give us a call or e-mail us to discuss sailing, ask questions, or order a new sail. We are here to help you achieve your sailing goals.

If you have any questions about Melges 24 Ullman sail trim that are not answered here, please contact us.