sailboat rigging tune

How To Tune Your Sailboat Rig

• August 2, 2023

Table of Contents

Sailing, with its perfect balance of adventure and tranquility, has enchanted mariners for centuries. Whether you’re cruising coastal waters or vying for victory in a thrilling regatta, your sailboat ‘s performance hinges on a seemingly unassuming yet critical aspect: rig tuning. Understanding how to properly adjust the tension in your sailboat’s standing rigging is the key to unlocking the full performance of the boat. In this article, we delve into the art of sailboat rig tuning, exploring the reasons why it is not only important but fundamental to achieving optimal performance, safety, and overall sailing enjoyment.

Why Tuning Your Rig Is Important

Tuning your sailboat rig is essential for several reasons that directly impacts your sailboat’s performance, safety, and overall experience. Here are the main reasons why rig tuning is important:

• Sailing Performance: Properly tuned rigging ensures that the sails are set up optimally for various wind conditions. A well-tuned rig allows the sails to achieve their best shape, providing better lift and speed. It improves the boat’s pointing ability, acceleration, and overall sailing performance.
• Sail Shape and Balance: Rig tuning helps control the shape of the sails, allowing them to perform efficiently. The correct tension in the rigging ensures the right amount of luff tension on the headsail, preventing excessive sag and maintaining proper sail balance. This, in turn, results in better boat balance and easier handling.
• Safety and Durability: An improperly tuned rig can lead to increased stress on the rigging components, mast, and sail. Over-tensioned rigging can cause excessive loads, leading to potential failures or damage. Conversely, under-tensioned rigging can cause the mast to pump or the rig to be unstable in rough conditions. Proper tuning helps prevent rigging issues and increases the overall safety and longevity of the rig.
• Weather Conditions: Different wind conditions require adjustments in rig tension. In light winds, a looser rig allows for a fuller sail shape, while in heavy winds, a tighter rig flattens the sails and depowers the boat. Adjusting the rig to suit the conditions helps maintain control and optimize performance.
• Boat Balance and Helm Feel: Rig tuning affects the boat’s balance and how it responds to the helm. Properly tuned rigging ensures a balanced helm and a boat that tracks well, making it easier to steer and reducing fatigue for the crew.

Regularly checking and adjusting the rig ensures that your sailboat operates at its best, whether you’re cruising or racing. If you’re unsure about rig tuning, consider seeking advice from a professional rigger or an experienced sailor to help you get the most out of your boat.

Sailboat Rig Tuning Process

Tuning a sailboat rig involves adjusting the tension in the standing rigging (shrouds and stays) to achieve the correct balance and shape of the mast and sails. Here’s a step-by-step guide to help you tune your sailboat rig:

1. Check the Basics:

• Ensure the boat is level and upright, preferably in the water, with the mast straight.
• Check that all turnbuckles are free and not corroded or stuck.

2. Determine the Baseline:

• Refer to your sailboat manufacturer’s manual, sailmaker ‘s tuning guide, or rigging expert’s recommendations for the initial baseline settings of your rigging tension. This usually includes the recommended tension for the upper and lower shrouds and forestay/backstay.

3. Loosen the Rig:

• Loosen all the rigging turnbuckles to the point where they are free to move. This step allows you to start with a clean slate and avoids putting undue strain on the rigging while adjusting.

4. Center the Mast:

• Use a measuring tape or a specific mast rake measurement tool to ensure the mast is centered and straight on the boat, both athwartships (side-to-side) and fore and aft.

Closed Reel Long Tape Measure – Flexible Fiberglass Double Face Printing Inch/Metric

5. Adjust Shroud Tension:

• Begin by tensioning the lower shrouds to the recommended baseline tension. Use a tension gauge, Loos gauge, or tensiometer to achieve the desired tension. Repeat this process for both sides of the boat.
• Next, adjust the tension in the upper shrouds to match the recommended baseline tension. Be careful not to overtighten any of the rigging.

Spinlock Rig Sense Tension Gauge for 2-5mm Wire

Sailboat Rigging Tension Gauge from Loos & Co., PT-2 Professional Hands-Free Force Gauge Up To 2,000 lb

Sailboat Rigging Tension Gauge from Loos & Co., PT-3 Professional Hands-Free Force Gauge Up To 4,500 lb

6. Check Mast Bend:

• Securely, attach the main halyard to the lowest point on the rear base of the mast. From there, tighten the main halyard until there is a fair amount of tension on it. The main halyard represents a straight line which is the base line for your measurement. If there is mast bend present, there will be a gap between the main halyard and middle of the mast at its furthest bend point. This gap is what is to be measured for your mast bend measurement.

7. Check Mast Rake:

• Mast rake refers to the fore and aft angle of the mast. It can impact boat balance and helm feel. Use a mast rake measurement tool or reference marks on the boat to adjust the mast rake as needed, following the manufacturer’s recommendations or your sailmaker’s advice.

8. Check Forestay Tension:

• Adjust the forestay tension to achieve the desired amount of luff tension on the headsail. For sailboats with adjustable backstays, make sure your backstay off off when taking this measurement. For boats with a fixed backstay, a proper forestay tension ensures proper sail shape and minimizes sag in the forestay.

9. Tune the Backstay:

• If your boat has an adjustable backstay, adjust it to control the bend in the mast and headsail shape. More tension on the backstay usually flattens the mainsail and depowers the rig, while less tension allows for a fuller sail shape.

10. Fine-Tuning:

• Go sailing and make small adjustments to the rig while underway to achieve the best sail shape and performance. Pay attention to how the boat behaves in different wind conditions and adjust the rig accordingly.

11. Periodic Checks

• Rig tuning is not a one-time task. Check your rig regularly for any changes due to sailing conditions, mast compression, or wear. Make adjustments as needed to maintain optimal performance.

It’s essential to keep a record of your rigging settings and changes so you can refer back to them and fine-tune your rigging over time. If you’re unsure about tuning your rig, consider seeking advice from a professional rigger or experienced sailor.

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How to tune your rig for optimal performance

Optimizing the performance of your boat's rigging system is crucial for an enjoyable and safe sailing experience. This guide provides step-by-step instructions for tuning your rig and maintaining your sails.

How to Tune Your Rig for Optimal Performance

Sailing is an art that requires constant learning and adaptation. One of the most important aspects of sailing is ensuring that your boat’s rigging and sails are in top condition. In this article, we will discuss how to tune your rig for optimal performance, ensuring that you and your family can enjoy smooth sailing on your adventures.

Table of Contents

Understanding the basics of rigging, the importance of rig tuning, step-by-step guide to rig tuning, sail improvements for better performance, maintaining your rig and sails.

Before we dive into the process of rig tuning, it’s essential to understand the basics of rigging. The rigging system on a sailboat consists of various components, including the mast, boom, shrouds, stays, and sails. These components work together to provide stability, support, and propulsion for your boat.

Mast and Boom

The mast is the vertical pole that supports the sails, while the boom is the horizontal pole attached to the mast’s base. The mast and boom are critical components of your rigging system, as they provide the framework for your sails.

Shrouds and Stays

Shrouds and stays are the wires or ropes that connect the mast to the boat’s hull. They provide lateral and fore-and-aft support for the mast, ensuring that it remains stable and upright. Shrouds are typically attached to the sides of the boat, while stays are connected to the bow and stern.

Sails are the primary means of propulsion for a sailboat. They work by capturing the wind’s energy and converting it into forward motion. There are various types of sails, including mainsails, jibs, and spinnakers, each with its own unique characteristics and uses.

Rig tuning is the process of adjusting your boat’s rigging system to achieve optimal performance. Proper rig tuning can significantly impact your boat’s speed, handling, and overall sailing experience. Some of the benefits of rig tuning include:

• Improved boat speed and pointing ability
• Enhanced sail shape and efficiency
• Reduced wear and tear on rigging components
• Increased safety and stability

By regularly tuning your rig, you can ensure that your boat is always performing at its best, allowing you and your family to enjoy your sailing adventures to the fullest.

Rig tuning can be a complex process, but with the right knowledge and tools, it’s something that any sailor can learn to do. Here’s a step-by-step guide to help you tune your rig for optimal performance:

Step 1: Inspect Your Rigging

Before making any adjustments, it’s essential to inspect your rigging for signs of wear, damage, or corrosion. Check all components, including the mast, boom, shrouds, stays, and sails, for any issues that may affect your boat’s performance.

Step 2: Set Your Mast Rake

Mast rake refers to the angle of the mast relative to the boat’s centerline. Adjusting the mast rake can have a significant impact on your boat’s balance and performance. To set your mast rake, follow these steps:

• Attach a weight to your main halyard and let it hang freely over the side of the boat.
• Measure the distance from the halyard to the boat’s centerline at the chainplates.
• Adjust the forestay and backstay until the desired rake is achieved.

Step 3: Adjust Your Shrouds and Stays

Next, you’ll need to adjust your shrouds and stays to ensure proper mast alignment and tension. Follow these steps:

• Loosen all shrouds and stays.
• Tighten the upper shrouds until the mast is straight from side to side.
• Tighten the lower shrouds to remove any side-to-side play in the mast.
• Adjust the forestay and backstay to achieve the desired mast bend.

Step 4: Check Your Rig Tension

Proper rig tension is crucial for maintaining sail shape and boat performance. To check your rig tension, follow these steps:

• Attach a tension gauge to your shrouds and stays.
• Measure the tension in each wire, adjusting as necessary to achieve the desired tension.
• Ensure that the tension is even on both sides of the boat.

Step 5: Fine-Tune Your Rig

Once your rig is properly tensioned and aligned, you can make any final adjustments to optimize performance. This may include adjusting your sail controls, such as the outhaul, cunningham, and vang, to fine-tune sail shape and efficiency.

In addition to rig tuning, there are several sail improvements that you can make to enhance your boat’s performance. Some of these improvements include:

• Upgrading to high-quality sails made from durable, lightweight materials
• Regularly cleaning and inspecting your sails for signs of wear or damage
• Using sail battens to improve sail shape and efficiency
• Installing a roller furling system for easier sail handling and storage

By investing in these sail improvements, you can ensure that your boat is always performing at its best, allowing you to enjoy your sailing adventures to the fullest.

Regular maintenance is essential for keeping your rig and sails in top condition. Some maintenance tasks to consider include:

• Inspecting your rigging for signs of wear, damage, or corrosion
• Lubricating moving parts, such as sheaves and blocks, to reduce friction and wear
• Replacing worn or damaged components, such as shrouds, stays, and sails
• Regularly cleaning your sails to remove dirt, salt, and other contaminants

By staying on top of these maintenance tasks, you can prolong the life of your rig and sails, ensuring that your boat is always ready for your next adventure.

Tuning your rig for optimal performance is an essential skill for any sailor. By following the steps outlined in this article, you can ensure that your boat is always performing at its best, allowing you and your family to enjoy your sailing adventures to the fullest. Remember to regularly inspect and maintain your rig and sails, and don’t be afraid to make improvements and adjustments as needed. With the right knowledge and tools, you can transform your boat into a high-performance sailing machine that’s ready to take on the open sea.

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Tuning A Sailboat Rig

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If your sailboat seems slower, follow our how-to on tuning your rig for optimal performance.

Photo: Bigstock

Spring is a time of prepping your boat for the coming season. While powerboaters fine-tune their engines, sailors should consider fine-tuning their rigs. Doing it yourself may seem intimidating, but it shouldn't be. Anyone reasonably handy can do it in a few hours. The reward is easier and faster sailing throughout the coming season.

Let's start with the basics for new sailors. With a few exceptions, a sailboat mast is held up by a series of stainless-steel wires. But those wires also perform several other equally important functions. When a sailboat is at rest and there is no wind blowing, the stress on these wires is very light with almost all the load downward toward the keel. However, when the boat is sailing and heeled over in a fresh breeze, more stress is placed on the wires and they have to work harder to hold the mast upright and stop it from bending.

The wires that prevent the mast from moving from side to side are called shrouds, and the ones that prevent fore and aft movement are called stays. The larger and taller the mast, the greater the load, and the number of shrouds and stays required. On a typical cruiser, say up to about 35 feet, there will generally be one forestay, one backstay, and two shrouds on each side.

To get the best performance from your boat and sails, the rigging needs to be set up correctly — often called "tuning the rig." The rig should be tuned with the boat in the water on a day with little to no wind. You'll also want to be away from wakes and other boats that can rock your boat. To start, the turnbuckles for the stays and shrouds should be hand-tight only. This is sufficient to hold up the rig but places no strain on anything — yet. Lay on your back on the boat's foredeck and sight up the front of the mast. It should be perfectly straight with no bends or kinks. Next, tighten the lower shrouds — these are the ones that do not go all the way to the top of the mast and often attach to the mast at the base of the crosstrees (the two horizontal spars at the upper ends of the topmasts).

You'll need a large screwdriver to rotate the turnbuckle, and a wrench to hold the shroud fitting and prevent it turning as you tighten. Give a couple of complete turns on either side. Have a helper release the main halyard and keep a little tension while you pull down the end that normally attaches to the mainsail until it just touches the top of the toerail adjacent to the chain plate. Have your helper cleat off the halyard, then swing the halyard over the boom and check the measurement on the other side. They should be the same. If not, adjust the turnbuckles until they the measurement is equal on port and starboard.

Adjusting and tuning a sailboat rig will often bring benefits such as easier handling and better performance.

Next do the same for the cap shrouds, these are the ones that go to the top of the mast, but note that due to the length of the shrouds, it is easy to bend the mast to either port or starboard. With the shrouds adjusted, sight up the mast one more time to ensure that it is still straight.

Next comes the fore and aft adjustment, which is made with the backstay and forestay. Masts should be plumb or lie back slightly. It should never rake forward. A good starting point is to tighten up the forestay and backstay a little over hand-tight. Use the main halyard as a plumb bob. Cleat off the halyard so the free end is just clear of the top of the boom and let it hang. If the shackle on the end of the halyard hits the mast, the mast is likely too far forward, so slacken off the forestay and tighten the backstay. Adjust a little at a time until the end of the halyard hangs free — 4 or 5 inches is a good starting point.

You'll need to install cotter pins into the turnbuckles to prevent them loosening over time, but before doing that, take the boat for a sail when the wind is blowing about 10 knots and see how everything works. With the boat on a beam reach, note the tightness of the windward shrouds. If they appear slack, they will need to be adjusted up. If the boat is hard on the tiller or wheel and tries to turn into wind, the mast has too much aft rake, so you'll want to slacken the backstay and tighten up on the forestay a little. If the bow wants to turn away from the wind, the mast is too far forward, so you'll need to move the mast back a little.

If you are at all unsure about tackling this task, play it safe and smart — seek out the services of a qualified rigger who has access to rig tension gauges and other specialized tools.

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Contributing Editor, BoatUS Magazine

A marine surveyor and holder of RYA Yachtmaster Ocean certification, BoatUS Magazine contributing editor Mark Corke is one of our DIY gurus, creating easy-to-follow how-to articles and videos. Mark has built five boats himself (both power and sail), has been an experienced editor at several top boating magazines (including former associate editor of BoatUS Magazine), worked for the BBC, written four DIY books, skippered two round-the-world yachts, and holds the Guinness World Record for the fastest there-and-back crossing of the English Channel — in a kayak! He and his wife have a Grand Banks 32.

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How to Inspect and Tune a Sailboat Rig

• By Ralph Naranjo
• Updated: May 14, 2020

Major mast failures usually begin as minor hardware problems. At least that’s what scrap-bin forensics seems to confirm. So, instead of dreading a dismasting, prevent it with a sensible approach to rig maintenance.

Some sailors inspect their masts and rigging with the spar stepped, but most recognize how much will remain unseen. Riggers recommend that the mast come out every few years and be placed on a pair of sturdy sawhorses ready for close-up scrutiny. My DIY approach focuses on hardware junctions and points where load paths intersect. Packed in my rigger’s bag are the usual hand tools, plus a Scotch pad, a quality magnifying glass and a small digital camera to record the findings. The old rule of thumb is that standing rigging has a decade’s, or one circumnavigation’s, worth of reliability; it’s a benchmark that remains valid today.

Another important issue is the rigging’s designed safety factor, or how much stronger the components are than they need be. The catch here is material deterioration over time, and the fact that there’s a direct correlation between stronger structures and increased reliability. For example, by increasing 1-by-19 shrouds and their attendant hardware from 5/16 inch to 3/8 inch, the higher safe working load translates into a longer life span. It’s a legit assumption, but doing so is both costlier and adds weight aloft, which can rob performance. The same tenets apply for a larger-diameter spar section and greater wall thickness. Engineers and naval architects try to balance these competing factors.

Some decades ago, I watched the deck-stepped spar of my first little cruising sloop drop into the drink. It drove home the fact that it really is the little things that count. In that case, it was a stainless- steel toggle, connected to an upper shroud turnbuckle, which had endured a few too many on-off load cycles. A tiny, nearly invisible crack had opened up, and salt spray had found a new home. The resulting corrosion tipped the scale and led to a dramatic failure. Since then, rig scrutiny has become my obsession.

The old rule of thumb is that standing rigging has a decade’s, or one circumnavigation’s, worth of reliability.

Wire and rod end fittings need a close look, especially in areas where there are brown stains and signs of cracks, pitting or other surface deterioration. This includes an evaluation of clevis-pin holes that should be circular, not elongated. Confer the same level of scrutiny to the clevis pins themselves. Don’t confuse stainless-steel clevis pins with chrome-plated bronze pins. The latter are just fine when used in bronze fittings, but when a bronze clevis pin is placed in a stainless-steel chainplate hole, the bronze pin can be carved away by the much harder stainless-steel chainplate.

My inspection process includes a rigging-wire wipe-down with a rag that easily snags on tiny cracks. It includes careful scrutiny of hardware junctions. I search for signs of chafe, especially where fiber or wire running rigging makes directional changes at sheave boxes, and around where the headsail furler’s top swivel rides. Looking closely at masthead exit points, I check for sheave wobble, excess side play and signs of pulley damage.

This is also the time to sort out halyards that are rubbing against external or internal obstructions. I use a bright, narrow-beam LED flashlight for a good visual inspection of the internal portion of the mast. Not only will it pinpoint screws and sheave boxes that might be causing chafe, but it also will help you untangle crossed halyards and confirm fairleads. While working at the heel end of the spar, look closely for corrosion and a condition riggers call “elephant foot.” It’s an actual wrinkling of the alloy tube section caused by too much compression and a too-thin wall section. It’s most often seen on raceboats with powerful hydraulic mast-adjusting systems, and on cruising boats that have pounded into too many steep wave faces.

Roller furling foils hide the wire or rod on which they spin. Rigging end fittings and terminals can usually be inspected, but a broken strand of wire inside the foil might initially go unnoticed, at least for a little while. This is another reason why offshore cruisers opt for a cutter or solent rig that adds a second stay for some extra ­insurance. Following the once-a-­decade rule, it makes sense to completely disassemble furling systems, and replace the wire along with any worn bearings, bushings or plastic spacers.

My inspection process includes a wire wipe-down with a rag that easily snags on tiny cracks. I search for signs of chafe everywhere.

Keep in mind that when the mast is unstepped, many roller furling drums and head foils (especially on boats with deck-stepped rigs) extend beyond the heel of the spar. If the yard doesn’t splint and immobilize the extended foil and drum, do it yourself. All it entails is a couple of 2-by-4’s, or a pair of old oars lashed or duct-taped to the mast just above the heel. This double splint should extend to the base of the roller-furling drum where it too is lashed or taped. It keeps the drum from dangling and bending the foil during transport, and while the rig is stored on a mast rack.

Spreaders also deserve a really close look. All too often, excess anti-chafe protection results in the spreader tips becoming a water trap that turns into a hidden corrosion bath. So, when the rig is down, cut away the spreader-tip padding, and use white vinegar and a plastic scrub pad to get rid of any white powdery oxidation. Remove the spreaders from the spar, and inspect the area where spreader bases make contact with the mast. Look for compression damage to the mast wall and signs of corrosion damage. If all is well, reassemble using one of the tried-and-proven water-resistant lubricants. I’ve settled on Lanocote, McLube Sailkote and Super Lube, using Boeshield T-9 and WD-40 as my go-to spray protectant and penetrant. Throw away the old cotter pins, and use new pins on all of the reassembled rigging.

“She’ll be right, mate,” was the favorite phrase of an old Kiwi friend, but it isn’t good advice when it comes to keeping the rig where it belongs. Don’t shy away from calling in a qualified rigger to handle larger problems.

Most boatyards will restep spars but won’t tune the rig. Their goal is to set up the mast and rigging to approximate how it arrived. Occasionally, they hit the mark and even replace the mast wedges appropriately. Otherwise, I wait for a flat calm to make sure that the boat has no list. This involves using a tape measure to confirm the athwartship trim (waterline to rail-height port equals waterline to rail-height starboard). Then I check the perpendicular and rake of the mast using the main halyard with a makeshift plumb bob (dive weight) attached. The retune requires loosening the turnbuckles and incrementally retensioning the rigging. Small amounts of headstay and backstay adjustment relocates the masthead, causing the makeshift plumb bob to move significantly. I use prior measurements from previous mast-tuning successes to set the rake to a sweet spot that, in the past, delivered a minimal amount of weather helm.

With the rake set, I insert a set of teak or high-density hard-rubber wedges between the mast and the mast partners. These wedge-shaped spacers have a top flange that prevents them from falling into the bilge when the mast compresses on one side of the partners and opens the gap wider on the other. With all the wedges set, I incrementally add tension to the rig, tightening headstay and backstay first, while carefully maintaining the rake angle. Next, I adjust the upper shroud (or V1), working from side to side to keep the mast perpendicular. Finally, I snug up (but not overtension) the lower and intermediate shrouds. This static tuning sets the stage for an underway final tune, during which I check how well the spar remains in column. Leeward bends and S-curves are problematic and must be minimized. Boats with discontinuous rigging have shrouds that are not one continuous wire run. They utilize turnbuckles located above spreaders that must be individually adjusted to eliminate side bend.

During sea trials, make sure the leeward standing rigging is not overly slack and flopping around like loose spaghetti.

Intentional fore and aft mast bending can influence sail shape, and is put to good use aboard raceboats. Adding such complication to most cruising boats, which are ­normally steered by an autopilot, makes less sense. In-mast furling spars are least happy with powerful hydraulic backstays bowing the mast. So, get sound advice from a rigger/mast builder before adding hydraulic sail-shaping gear.

A sea trial should follow your static mast tune. And as you beat to windward in a modest 10- to 15-knot true breeze, check the leeward standing rigging. Make sure it’s not overly slack and flopping around like loose spaghetti. If so, add more shroud tension to both sides. A tension-testing gauge will work, but many sailors do fine estimating by hand. Cruising-boat rigs shouldn’t have the same amount of rig tension as a raceboat ­beating to windward. However, if your sailboat’s mast is deck-stepped, make sure the coachroof isn’t deforming due to the compression load. A compression post, ring frame or other rigid structure should be spreading such loads. If you’re unsure of the correct rig tune, arrange a session with a rigger or sailmaker—and start the season in optimized trim.

Technical expert Ralph Naranjo has inspected the rig on his Ericson 41, Wind Shadow , on countless occasions.

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What You Need to Know About Rig Tune & Performance

For many sailors, the relationship between rig tune and performance often seems like a black hole. Quantum’s Dave Flynn takes us on a tour of the core elements of the rig and what you need to know to demystify tuning for optimum performance.

Mastering rig tuning for optimal sail trim and performance might seem daunting, but fortunately it’s not as complicated as tuning a Stradivarius violin! To keep it in perspective, remember you are just pulling on a hunk of aluminum or carbon with cables. To master the rig, there are four elements you need to understand: rake, athwartship tuning, mast bend, and headstay sag. Each of the four elements of rig tune either adds power or takes it away. If you understand the basic mechanics of each element, you can tune your rig to improve trim and overall setup.

Mast rake is a measure of how far the mast is angled aft from a straight vertical. A typical mast rake ranges from one to one-and-a-half degrees on a cruising masthead rig to as much as four degrees on a fractional racing rig. A mast should never be raked forward unless there is something unusual in the boat design (You’ll know if this is the case!). When you add rake to the mast, you tilt the whole sail plan aft. This, in turn, shifts the power aft, pushing more load on the stern and forcing the bow up into the wind, creating weather helm.

Rake is determined by headstay length: The longer the headstay, the greater the rake. To adjust your rake, adjust the length of the headstay. How much rake a boat needs to generate the right amount of weather helm is a function of hydrodynamics (hull form, keel shape, and placement). In most one-design racing classes, where lots of time is invested in figuring out what works best, tuning guides specify headstay lengths for conditions. In more developed classes, this will change as a function of wind speed. You’ll want more rake in light air when it is hard to generate helm and less as the breeze builds. For boat setup and trim, adding rake is a tool for generating power in light air, and reducing rake is part of the de-powering process in heavy air.

For cruisers and many non-one-design rigs, you likely don’t have a tuning guide to work from, so to optimize upwind performance you need some helm loading in light-to-moderate conditions. Three to five degrees of rudder angle in 8kts-10kts of wind is a commonly cited target. To test if this angle works for you, sail upwind in 8kts-10kts and let the helm go; the boat should turn gently into the wind. If it goes straight or bears off, you need more rake and vice versa if it spins out of control. Don’t try this test when it is windy; your boat will round up and exhibit too much helm due to heel not rake, and you’ll get a false read. 

ATHWARTSHIP TUNING

If the rig is not centered, performance and trim will be different tack to tack. To remedy this, center the top of the rig. Using the diagonal shrouds, bring each successive panel in line with the top. The amount of tension you need is tough to predict at the dock–the mast really needs to be under load. Test tension by sailing upwind in 10kts-12kts of breeze with appropriate trim settings and then check the mast. Is it straight when you put your eye to the aft face and look up the mainsail track? If the tip is falling off, you need more upper tension. If the leeward upper shrouds are flopping around, you need more tension for a given velocity. The shrouds should be firm.

Work on the diagonals next. How much tension you need in the leeward diagonals is determined by how stiff the mast is. In over 10 kts, you definitely want the mast to be straight. For more power in light air, you can let the middle of the mast sag an inch or two to leeward to increase the depth in the mainsail. It is common in one-design classes to ease tension on the diagonals in light air to create this smooth sag.

Dinghies and small keelboats are great boats to experiment with how tuning inputs affect your sail plan. The smaller diameter wire shrouds and relatively small masts dramatically show the impact of tuning adjustments. This isn’t as visible on larger racing or cruising boats with rod rigging. Cruisers will want to set a good base athwartship tune as well. If the rig is uneven side-to-side, you will experience frustrating differences in point and power on each tack. Skip the headache and set a good base tune early in the season. Whatever the condition you are sailing in, once you have established good upwind trim, have a look up the mast to make sure it is in column or sagging slightly to leeward in the middle in light air.

If you have an older cruising boat with a mast stiffness that resembles that of a telephone pole, you can skip this section! But for cruisers with a relatively modern rig, swept-back spreaders, traditional sails with flaking system, or even in-boom or in-mast furling, pay attention here.

While rake is the amount the mast is angled aft, mast bend is the amount you bend the mast aft after you have set your rake. A rig that bends gives you a powerful tool for changing the shape of the mainsail: More mast bend flattens the sail and de-powers it; a straighter mast creates shape and power. Rig tune affects how much a mast bends, particularly on modern fractional rig boats with swept back spreaders. But no matter what type of rig you have, you want to start with a little mast bend, or pre-bend, which refers to the amount of bend that has no backstay tension. Lengthening the headstay increases the bending moment and adds pre-bend. This is why it’s important to set the rake first. Other factors affecting the pre-bend are the position of the mast step and the blocking of the mast in the partner, which is the hole where the mast goes through the deck. To add pre-bend, either move the mast step aft or move the mast forward in the partners. A target of 1”-3” of pre-bend is typical on a medium-sized boat. Pre-bend ensures the mast will move forward in the middle and flatten the mainsail when you pull on the backstay.

On a rig with in-line spreaders (typically masthead rigs), the side shrouds have little impact on the mast bend created by pulling on the backstay. On some rigs, however, there are check stays to keep the mast from bending too far. Sometimes there are even multiple sets.

How far is too far when bending the mast? You’ll know when your mainsail develops diagonal wrinkles from the clew up to the luff and is beginning to turn inside out. For maximum de-powering, bend just to the point where wrinkles appear. If available, use check stays to help.

On modern fractional rigs with spreaders swept well aft, the side shrouds have a big impact on mast bend. The diagonal shrouds are controlling not only athwartship tuning but also acting like check stays to inhibit mast bend, since they are swept back and pulling aft. Too tight, and the diagonal shrouds will keep the mast from bending and flattening the mainsail; too loose, and the mast can over-bend and turn the sail inside out. In many classes, overall rig tension is increased by taking turns on the shrouds, shortening the headstay, or pumping the whole rig up with a mast jack for more backstay tension without allowing the rig to over-bend as it gets windier.

HEADSTAY SAG

If some mast bend is good, why isn’t more better? The answer is headstay sag. When the headstay sags, the headsail becomes full and more powerful, which is great in light conditions. But as the breeze builds, you want to reduce the amount of sag as much as possible to de-power the boat and help with pointing. In breeze, it’s all about headstay tension–you can’t get too much. So why is mast bend a factor? When you pull back on the rig with the backstay, it will tighten the headstay, which is good. But you are also pulling down and compressing the rig, which makes it bend. You want some mast bend in order to flatten the mainsail, but not so much that you soften the whole rig and increase headstay sag. This is why we use check stays to control mast bend on a masthead rig and tighter diagonal tension on a swept aft spreader rig.

Rig tune still matters even when you aren’t routinely adding turns to your shrouds based on the wind and conditions. Many modern cruising sailboats with in-mast furling rigs have comparatively smaller tune adjustments, as the rig needs to stay in column for the mainsail to furl properly. Some boats are outfitted with a cascading backstay adjuster that allows for minor tweaks and lets you easily reset the rig when it’s time to furl the mainsail. To get the most performance from your cruising setup, don’t overlook rig tune. Racing sailboats often have their rigs removed for transport and then re-rigged, whereas many cruising boats may never have had the rig adjusted since the boat was first commissioned. If you can't remember the last time your rig was tuned, now is a great time to give your local loft a call.

Having a properly tuned rig is essential to boat setup and performance. While this can be a DIY process, if you have questions or need additional input, please contact a professional rigger or your local loft where our expert Quantum team can help sort out your rig and tune. For one-design tuning guides and resources, select your OD class on the Quantum website or get in touch with a Quantum Class Expert.

Get in touch with David Flynn with additional questions and dive deeper into rig tune for performance. E: [email protected] P: 410-268-1161 ext. 206

The Discussion

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Solo Challenge

Standing rigging: step by step guide on how to tune it on your sailboat

• Marco Nannini

In this article we will deal with the tuning of standing rigging of a typical sailboat. Speaking of standing rigging we have to open a parenthesis on the types of rigs possible for a sailboat.

Please note this article is a translation and may contain some errors for which I hope you’ll forgive us!

Standing rigging: the evolution of rig types and their tuning

Historically, the most traditional rig type is the masthead one. That is with the forestay and backstay attached to the masthead as fixed standing rigging that create traction in the opposite direction. The spreaders, in this case, are in line, perpendicular to the fore and aft axis of the boat. With a masthead rigged boat, the backstay can be used to increase forestay tension in high winds. At the same time, by vertical compression of the mast, tensioning the backstay causes a bending of the mast that flattens the main. The backstay is both an element of the standing rigging but can also be tuned.

Tensioning the backstay, the central part of the mast advances forward creating a slight “C” shape of the mast seen from the side. This curvature lets you bring the “fat” of the mainsail forward flattening the sail. Therefore, with a strong breeze, we can intervened on the backstay to reduce the forestay sag and flatten the mainsail. Both operations improve upwind performance.

Fractional rigs

For decades now, however, “fractional” rigs with swept back spreaders have been increasingly widespread. In this case the forestay does not reach the masthead but only up to seven eighths or nine tenths of the mast height and so do the attachments of the shrouds. The spreaders are not perpendicular to the fore-aft axis but swept towards the stern on the horizontal plane. The swept back spreaders ensure that the mast can stand up even without the backstay, which is no longer “structural”. That is, it is no longer one of the elements of the standing rigging (albeit adjustable). It becomes simply the means to adjust the mast bend and curvature and would be considered and its control line is therefore part of our running rigging.

This development has become more and more marked with boats with very wide spreaders and without backstay. The evolution started with offshore sailing boats such as the Mini 650s and Class40s and now it is very widespread also among cruising sailboats. By completely eliminating the backstay from the the list of elements constituting our standing rigging, which presented itself as an obstacle to increasing the roach of a mainsail, it is now possible to have all the roach we want and even “square top” mainsails.

Standing rigging tuning on fractional rigs with swept back spreaders

We will talk here specifically about boats with swept back spreaders. We have chosen a Class40, a sister-ship of the boat with which I competed in the Global Ocean Race 2011/2012. It’s a popular model of Class40, a first generation Akilaria RC1, designed by Mark Lombard, from around 2006. The rig of this boat is not particularly “extreme” or delicate, being the Class40s designed for great ocean navigation. The standing rigging is all rod on this boat.

Although the mast is made of carbon rather than aluminium, the rig is the same as that of a Mini 650 Pogo2 from Structures shipyard. The Pogo 2, designed around 2003-2004 is the Mini 650 with most boats built. This type of rig, nine tenths fractional, has two orders of spreaders. There is no backstay at all, which is common on many modern boats. By now, I would say, even on cruising boats it is one of the most common rig arrangements. It is adopted by shipyards such as Jeanneau and Beneteau, even for boats without oceanic ambitions.

This type of rig is fitted with a runner at the mast top and a checkstay at the height of the inner forestay. Runners and checkstays are not structural, therefore are not to be considered part of the standing rigging per se, the mast does not need them to stay up. I jibed without runners in 50 knots of wind and nothing happened. That said, runners and checks play a very important role in stabilising the mast and reducing its stress. When I run my training centre I used to say that they were not part of the standing rigging but that for good practice we would treat them as such.

Standing rigging and structural lazy jacks

As said, the backstay is simply not there, to make room for the “square top” mainsail. This is the same both on Mini 650s and on Class40s. There isn’t even a topping lift to support the boom when reefing. On a Mini 650, to avoid too many lines, and with a boom that weighs a few kilos, nothing replaces the topping lift. This means that when the main halyard is released, the boom falls onto the coach-roof. The boom will rise again when we tension the reef line and this rarely even needs the boom to be helped by hand.

On the Class40, even though the boom is made of carbon, we can imagine how much the boom plus mainsail would weigh especially if full of water. The problem is solved with the introduction of “structural lazy jacks”. What is meant when we say they are structural? Their role is not simply to contain the main when dowsing it. They replace the topping lift and support the boom. Usually they are made with dyneema and not just simple polyester. They are adjustable both to raise the boom in port and to put them at rest during navigation.

Standing rigging and runners and checkstays

On boats with swept back spreaders, runners and checkstays are not structural. Despite the absence of a backstay it’s not runners or checkstays that keep the mast up. That said, they play a very important role – they help provide additional support for the mast. For example, for ocean-crossing boats, runners and checkstays help stabilise the mast and prevent it from pumping or bending. In addition, runners reach the masthead. With a fractional rig they provide extra support, and become partially “structural” in reducing the workloads of the last part of the mast not reached by the shrouds.

That said, on a nine-tenths rig it is unlikely that you could break the mast tip under spinnaker just because you did not set the runner. I am not aware of any such cases among Class40s. Certainly distributing the tension between runner and checkstay greatly reduces the load of the standing rigging. The checkstay, on the other hand, usually points where the foresail forestay attachment is located. In addition to acting as a support for the mast in general, it allows you to decrease forestay sag without adding compression to the mast.

Standing rigging: how to proceed with tuning your standing rigging

After this introduction, let’s move on to a practical case. Let’s consider the mast of a Class40, with two orders of swept back spreaders and its standing rigging. Hence, we have non-structural runners and checks, no backstay and no topping life. When I arrived on this boat to check the mast, there were two problems noticeable with the naked eye. First of all, the mast was not straight, it pulled to the left until the first set of spreaders. Then it made a bend to the right and then back to the left between the second set of spreaders to the masthead.

Seen from the side, the mast showed excessive rake and pre-bend that needed correcting. So we had left-right and fore-aft problems. In addition to this it was clear that when the starboard runners and checkstay were tensioned, the mast deteriorated in shape. In particular, the curvature between the first set of spreaders and the masthead increased. To fix a mast like this, with multiple problems, you need to have a method to get to a satisfactory result.

As for the adjustments to runners and checkstays, I leave them last, as we will see there are various options on how to use them. First we wanted to take care of putting the mast straight and solve the problem of its excessive rake. The rake shifts the sail centre aft and the bend in the mast flattens the sail, both of which we do not want in light winds. Since this boat is sailed in the Mediterranean we must have a good light wind setup and be able to intervene on the shape of the sail as the wind increases.

Standing rigging: how to put straighten the mast

The boat was in the water, we first had to avoid the risk of unscrewing a turnbuckle and accidentally unhooking a shroud. Since it was not me who had mounted the mast, I could not be sure that the turnbuckles had been inserted correctly, i.e. be exactly level with the same number of turns on the upper and lower par. This means that the threads are not screwed in equally. The lazy rigger screws the turnbuckle on deck a few turns so that he has only to hook the vertical shroud, the V1.

So, in order to avoid any dangers, we set the inner forestay (to double up with the forestay). We also set runners and checkstays just for safety. These work laterally to support the mast. We also attached spinnaker halyards one to the left and one to starboard to an eyebolt.

With a bent mast the first thing really is to understand was why it is so. So we measured the total length of the left and starboard turnbuckle system for both the vertical shrouds (V1) and the low diagonals (D1). Differences emerged immediately, the D1 on the left was about 1cm shorter than the one on the right. This explained why the mast started veering to the left. The port V1 was 2cm shorter than the starboard V1. This explained why the head of the mast pointed to the left after the initial bend. The curve to starboard between the first and second set of spreaders was attributable to the upper diagonal D2 on the starboard side, which was tighter than the left one.

Standing rigging: resetting everything to zero

With the boat in the water and not wanting to take any risk, we didn’t want to get to unhook any turnbuckle. This is to avoid the unpleasant situation of having a hard time getting to re-attach one. This could happen if there’s something inherently wrong with the measures taken that would forced you to work at the limit of the available turns. However we had to make some assumption and one was that each pair of shrouds would be the same length. I.e., that the problems were only in the adjustments of the turnbuckles.

When riggers cut rigging in the workshop they are very unlikely to make pairs of shrouds of different lengths. Therefore, except in exceptional cases, starting from this assumption is more than reasonable. By measuring the total length of the turnbuckles and exposed thread, many things could be deduced. In our case it was evident that the port turnbuckle had many more turns than the starboard side, compared to the thread of the V1 above. That is, the turnbuckles had not been hooked and tightened at the same simultaneously on lower and upper thread.

First of all, we unscrewed the turnbuckles of the V1s, whilst holding the upper threaded part integral together with the turnbuckle. This is possible because the rod shroud is free to rotate inside its T-Cup at the spreader. If it does not rotate, spray some WD40 but never twist the rod rigging. With this procedure we were able to restore a situation where the two V1s shrouds were the same length and with the same adjustment. We repeated the exercise for the low diagonals D1s.

Standing rigging: loosen everything

To bring everything back to zero tension, I went up to the first set of spreaders and loosened the D2s which I would then adjusted last. For the moment I wanted to see the mast without no tension in the D2s. Their role is to prevent the mast from bending to leeward between the first and second spreader levels, especially upwind. As we were stationary in port and without sails, I could totally ignore the D2s until the end.

After that I went back to looking at the mast track and, no wonder, the mast was perfectly straight on the left-right axis without any curvatures. This is not to say it was already set right, but we had zeroed the lateral tension errors.

Standing rigging: rake and pre-bend

The rake depends on the relationship between the length of the forestay and the shrouds as a whole. On this boat only the V1s on deck are adjustable, the rest of the shroud is of fixed length. So the rake is controlled by adjusting the stay length and the V1s. The bend instead arises from compression of the mast given by the tension of the V1s, these pull down the mast that bends forward. The tension of the low diagonals D1s controls the angle up to the first set of spreaders of the overall curvature that the mast takes up to the masthead.

To reduce the bend we had to reduce tension of the V1s but also monitor the tension of the D1s. That is, if the D1s are too tight and the V1s too, we can even force in an inverse curvature. I.e the mast will go backwards to the first level of spreaders then stard bending forward from there to the masthead. This especially with loose D2s that do not prevent the section above from bending forward.

We therefore started by loosening the V1s by two full turns, observing a reduction the bend. The overall rake was still excessive. This can be measured by hanging a full bucket of water on the main halyard and letting it hung just above the deck. The distance between the halyard and the mast at the boom is your rake. We had no option but to intervene by shortening the forestay, which in this case was adjustable.

Standing rigging: adjusting the forestay

The forestay turnbuckle in this case, and like on many other boats, was inside the furling drum. Once the sail was lowered and the retaining bolts were unscrewed, it was possible to raise the drum and access the forestay turnbuckle. Before tightening the forestay, however, I wanted to loosen the the V1s a little so as not to induce further compression in the mast. To preserve the left-right adjustment symmetry, we unscrewed the V1s turnbuckles two full turns each side. We took then tightened the forestay by the same two full turns on the turnbuckle.

Each complete turn corresponded to approximately 3-4 millimetres in length. Two full turns lengthened the V1s by 7-8mm and the impact was visible to the naked eye. I could measure the rake with a bucket, but I had somewhat of a historical memory of the setting of that mast. In fact, I had sailed on an identical boat for a total of about 60,000 miles. So in all fairness, I was trusting my eyes. We removed two more turns from the V1s and took them back at the forestay. A change of about 1.5cm that was well noticeable at a height of 20 meters.

For example, when setting the runners, it was noticeable that the working points of the control lines had moved by about 20cm. The de-multiplication of the runner pulleys obviously amplified the effect on the control line. It was clear, however, that we had moved the mast head forward several centimetres and the excess rake was gone. We gave the forestay one more turn and removed a turn from the V1s and we were satisfied. The amount of rake optimal rake is usually provided by the designer so you can do this job with absolute precision.

Standing rigging: pre-bend

The pre-bend, at a given a setting of the V1s, is controlled by the tension of the D1s and D2s. The goal is to give the mast a beautiful shape that does not have strange kinks in its curvature and especially any inversions etc. In our case the mast bent too far forward and the forestay was particularly soft. This meant that the V1s tension encountered no resistance to mast compression. With the D2s completeley loose, the D1s were obviously too soft too. All the vertical tension turned into compression and bend.

By giving the D1s a few symmetrical left-right turns we were able to straighten the lower part of the mast. The curvature was accentuated between the first spreaders and the masthead so I went up to the D2s to give a first rough and symmetrical adjustment. Once on deck I noticed that the mast was much better already, the forestay was tighter, even though we hadn’t touched the V1s at all. But, the overall curve of the three “sections” of the mast was not yet regular. I therefore decided to tighten further the D1s by a turn and the D2s by two.

Looking at the mast from the side you could see a beautiful shape without irregularities that gently curved back. I was satisfied with the shape and only the sea trials could have confirmed the correct setting of the D2. If these are too soft the mast will sag to leeward between the first spreader and masthead. If they are both too tight the mast becomes straight like a telegraph pole losing its beautiful shape.

Standing rigging: the overall tension of forestay and V1s

For a rod of the size we were adjusting we needed a large and very expensive tension measurement tool. The spring-loaded ones suitable for adjusting the shrouds of a Mini 650 are useless. So, I resorted to trusting my “sensorial” memory. Taking V1s and D1s and shaking them,  hitting them, you get a feel for their. Shaking the furled headsail gives an idea of ​​the tension of the forestay. I relied on my historical memory and everything seemed to me in order.

The mast of the Class40s are, pass me the term, quite “ignorant”, and don’t it is not about fine tuning that last half turn. These are boats where you usually an average setting and not touch it before a specific event. This is because upwind mast is fully loaded at just 15-16 knots after which you need to reduce sail. So unless you had to do a short inshore event with light airs predicted changing the setting for each and especially longer races makes no sense.

We had created a perfectly straight mast track, an adequate rake and a pre-bend. It was time to move on runners and checkstays to decide if something needed changing. Before adjusting them, however, we could use them to do a test on the adjustment so far of our mast. I.e. tension them and observe the effect on the mast, which for this type of boats does not have to be significant (I’ll come back to this point). Tightening the left runner-checkstay pair seemed more or less ok. Starboard we clearly had a problem, the mast would bend to windward at the height of the second set of spreaders.

Adjusting runners and checkstays

On this Class40 the runner was attached to the first pulley and therefore its length was a given and could not be adjusted. The checkstay, instead, was tied to the first pulley with a lashing so that it could be adjusted in length. As mentioned, runners can be used in different ways. On some boats a loop with T-bone is is used to shorten the checkstay lashing by a few centimetres. With this expedient you can shorten the checkstay relative to the runner to the point that you set the checkstay and the runner remains effectively loose.

When the T-bone is undone, the runnner has more relative tension than the checkstay as by undoing the T-bone we have effectively lengthened the checkstay. This allows us to run high and increase mast bend with a full mainsail. Once the wind increases and we take the first reef, the runner is no longer needed (especially upwind). So we can put back the T-bone that shortens checkstay and use it as a counter cable for the inner forestay. The inner forstay and the staysail come up in about 16 knots of wind.

This system with T-bone on the checkstay give you maximum flexibility and is obviously suitable for those who know how to use it. However, in long race, especially single-handed, offshore, it has some “human” contraindications. Having to remember this T-bone day and night in every situation is not the best of proposition. We have also said that the mast of a Class40 is not quite so bendable and adjustable. The t-bone extra adjustment will not give you extraordinary gains and advantages upwind as there’s only so much extra bend you can put in with a runner and loose checkstay. All in all it will probably only change your solent to staysail switch point by a knot of wind or two.

A setting for inshore events and one for offshore racing

My personal opinion is that when offshore racing it is best to avoid easily avoidable risks. This T-bone, if forgotten closed, supports the mast only at the level of spreaders, leaving the masthead free. Imagine bearing away, removing the genoa and hoisting a large spi. Suddenly you run the risk that with enough wind the checkstay could even cause the mast to reverse its curvature with the masthead going forward and the lower part held back by the tight checkstay.

Balancing the risks and benefits, at the end of the day, on my boat I decided to eliminate the T-bone and seek for a medium setting. To do this we tighten the runner with the checkstay lashing very short to start with. We progressively lengthen the checkstay lashing until we get to a setting where, when tightening runner and checkstay there is a similar tension on both. If we observe the mast we will also notice that this setting will mean that when tightening runners and checkstay there isn’t much change in mast shape. We forego some fine tuning for safety offshore.

The very fact that the mast remained straight even when runner and checkstay were tightened gave me good confidence that I had already adjusted the D2s correctly. In fact, if the D2s had been too soft, when tightening the checkstay the mast would bend to windward. I can do the reverse test and see if the opposite set causes bend to “leeward”. If the D2s are set correctly setting each pair of runners and checks in turn should not produce any curvature either side from the first spreader to the masthead.

Standing rigging: sea trials

Having worked and checked with runners and checks the sea trial was more for the pleasure of ending the day with some sailing. The wind was not much but enough to load the mainsail close-hauled and verify that the mast remained straight. We had no doubts having already simulated the effort with checkstays. Everything was in order throwing in a few tacks confirmed that the boat made sailed the same angle to the wind on both tacks. This was not the case before, with a perceptible difference of several degrees.

Standing rigging: conclusions

Adjusting the rigging of a sailboat is less complicated than you imagine. But I have seen many badly adjusted masts and not by just a little. If you put your hands on the standing rigging without following a sequence and without knowing what you are doing, you end up like a dog chasing its tail. It is important to understand the influence of stay-V1 on the rake. The influence of forestay-V1 and D1 on the bend of the mast up to the first spreader. Finally, the role of the D2s in counteracting or favouring the bend between the first set of spreaders and the masthead. This on a mast with two sets of spreaders.

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Yachting Monthly

• Digital edition

Sailboat rigging: What is the best way to tune it?

• Ben Sutcliffe-Davies
• March 8, 2022

Is it best to tune your sailboat rigging on the hard or back on the water? Marine surveyor Ben Sutcliffe-Davies answers readers' questions

Where is the best place to tune your sailboat rigging? Credit: Colin Work

Is it best to tune your sailboat rigging on the hard or back on the water?

My Contessa 26 has been lifted out for the winter, but I will need to tune my rigging ahead of the sailing season.

Is it best to do this while the boat is still on the hard or wait until it is back in the water?

Is there an easy way to tune my rigging?

Louisa Moore

Ben Sutcliffe-Davies responds:

This is a really interesting question.

In my view, anything like rigging or shaft alignment should always be done with the craft afloat.

With regards to tuning, it depends on what the owner is intending on doing during the season.

A proper rig check should consider the age of the wire, chainplate, back stay and fore stay security.

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Make sure you check the mast step for compression issues.

There are several really good and quite reasonably priced books on setting up the rigging; for the more serious you will need to buy a proper rigger’s gauge.

These can range in price from a couple of hundred pounds to £800-£900.

Often it is better to pay a rigger for a check and set up so you have some peace of mind.

Submit your questions to our experts by emailing [email protected]

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Practical Boat Owner

• Digital edition

Rig tuning: a practical guide for sailors

• August 28, 2023

Correct rig tension will maximise the efficiency of your boat’s sails as well as reducing stresses on the mast. David Pugh demonstrates simple rig tuning

Safety is the number one benefit of tuning your rigging

As a cruising sailor, it’s tempting to simply set up your sail boat rig at the beginning of the season, then leave well alone.

Perhaps you leave the mast up, perhaps you mark the position of the turnbuckles before the mast comes down, perhaps you set the rig up from scratch or perhaps you pay an expert.

All these can work, but none are immune from one basic problem: boats move.

How much depends on the boat’s construction, particularly whether the mast is keel- or deck- stepped, but most will do so within a few days or weeks after the initial rig tension is applied.

The boat may continue to do so over time and rigging may stretch, especially when new, so it’s worth knowing how to correct it yourself.

My own boat, Contessa 26 Red Dragon , is a devil for this.

During the winter she sits on a trailer with the mast down, the keel supported along its length and in turn supporting the superstructure, aided by six pads and a bow post bearing on the boat hull .

At launch, these forces all change: the buoyancy of the hull now supports the keel, and the mast foot pushes down on the laminated deck beam under the step.

The rigging, meanwhile, increases the pressure on the step while trying to pull the chainplates through the deck.

I’ve never measured her beam before and after applying rig tension, but I suspect she becomes significantly wider.

She certainly doesn’t maintain her initial rig tension.

Benefits of rig tuning to get the correct tension

The first and most fundamental benefit of correct rig tension is safety.

An improperly supported mast is put under all sorts of stresses that it is not designed to endure, and dismasting can be the result.

Try sighting up the mast when the boat is close-hauled in a good breeze.

If the lee shrouds are slack and the middle or top of the mast is sagging to leeward, your mast is not properly supported and you should check your rig tension.

The second benefit is efficiency.

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The combination of rig, spars and sails is anything but simple, and if your s ailmaker has done their job properly and measured your boat rather than making your sails from documented figures, the luff curve of the main and the hollow of the jib or jibs will have been cut to suit the bend in the mast and the forestay tension at the time of measurement.

That means you’ll need to be able to replicate that situation when you set up the rig in order to gain maximum efficiency from your sails.

And, just to make things harder, as time goes by and your sails stretch, these optimum settings will change.

Conditions also affect the best settings for your rig.

Light airs demand softer settings than sailing in a gale, and you’ll often see racers tweaking their rig tensions to suit the conditions.

For cruisers seeking to set up and forget about their rig, the best option is to err towards setting up the boat for stronger winds, especially with shroud tension.

Forestay tension can be more dynamic, provided your boat has an adjustable backstay.

Simple rig set up

Some boats have designer’s recommendations for mast rake, bend and rig tension – if yours is one of them, follow the instructions.

The rest of us are obliged to make it up from scratch – so where do you start?

While some professional riggers might be able to assess the tension in a wire with a carefully calibrated shove, the rest of us need a bit of help.

You can either buy a rig tension gauge or measure the extension of the wire.

This latter method works on the basis that, for 1×19 rigging wire, an elongation of 1mm over 2m equates to 5% of the break load of the wire.

Seldén have a good explanation on their website – search ‘Seldén rig set-up’.

The tension you are aiming for will vary from boat to boat and between types of rigging wire, but a gauge will make it much easier to keep the tension even on opposite shrouds.

For the initial set-up the boat should ideally be floating level – it makes it much easier to see whether, despite the measurements, everything looks right.

I find it’s best to be on a finger berth, which allows you to get off the boat to assess whether the mast is upright.

Make sure that the mast is upright

If you’re starting from scratch, begin by centring the mast in the boat.

Leave the lowers fairly slack and use the main halyard to measure to the chainplates on each side.

You can then adjust the bottlescrews to make sure the cap shrouds are of equal length.

Use the main halyard to measure to the cap shroud chainplates on both sides

If your boat is symmetrical, the mast will be upright.

If your mast is keel-stepped, insert the chocks in the partners now before you apply rig tension.

Finally, tighten the cap shroud bottlescrews hand-tight, making sure you put the same number of turns on each.

Set up the mast rake

Next, set the mast rake. If you have a setting from the designer, use it.

If not, you’re most likely looking for a rake of between 1° and 2°, or 1:60 to 1:30.

So for a 9m mast, you would expect the offset between masthead and mast foot to be between 15cm and 30cm.

Measure it by hanging a weight from the main halyard and measuring the distance between the weight and the mast foot.

The forestay bottlescrew sets mast rake

If it’s windy, hanging the weight in a bucket of water will help damp the swing of the halyard.

Pull on a little backstay before using the forestay bottlescrew to move the masthead fore or aft and adjust the rake.

The backstay helps the masthead to move – with no tension, the forestay will simply become slack as you back off the bottlescrew.

Steeper rakes tend to go with fractional rigs, but this is by no means a rule – you may need to experiment to find what works for your boat.

Increasing the rake will increase weather helm , and vice versa.

Tension the cap shrouds

It’s now time to begin tensioning the rigging properly.

Take the slack out of the lowers at this stage, but don’t tighten them fully yet.

Then, using your tension gauge and making sure you keep the number of turns on each side equal, tension the cap shrouds to their working tension.

Most tension gauges are calibrated to show a percentage of the breaking strength of the wire: with my boat, I find that around 15% is sufficient to keep the rig taut in the conditions in which we sail.

A gauge makes rig set-up easier

If you have a keel-stepped fractional rig with swept spreaders you should carry out this stage with the backstay fully tensioned, as it will initiate a bend in the mast which is fixed by tightening the caps.

If you do this, be careful that the mast does not go out of column side to side – if it does, ease the backstay slightly.

Once the caps are tensioned, sight up the mainsail luff groove to check whether the mast has any bend, fore and aft or side to side.

If you have swept spreaders you can expect it to have some fore and aft bend, but otherwise it should still be in column.

If it isn’t, don’t worry too much unless the bend is large, as you can remove small errors with the lower shrouds.

Sight up the luff groove to check that the mast is in column from side to side

Set the mast pre-bend

The lower (and intermediate, if you have them) shrouds are your opportunity to set fore and aft mast bend, as well as preventing the middle of the mast sagging off to leeward.

It’s advisable to have at least some pre-bend in your mast to avoid it inverting downwind.

For straight spreader rigs, the lowers do all the work in setting bend. Start by tensioning the babystay or forward lowers.

The optimum amount depends on how your mainsail is cut – for a stiff masthead rig like mine I only look for about 10cm of bend with the backstay off, measured by holding the main halyard tight to the foot of the mast and eyeballing the deflection.

Use a second spanner to hold the shroud still when tensioning the bottlescrew

This usually equates to around 7% of the wire break load on the gauge.

For more flexible masts and fractional rigs, you will probably need more bend.

Again, use the tension gauge to keep the tension even from side to side.

Finally, tighten the aft lowers, enough to remove any slack but not to significantly alter the mast bend.

Swept spreader rigs will tend to have lower and intermediate shrouds set abaft the mast, so the simplest thing to do is to tighten them enough to maintain the bend set when you tensioned the cap shrouds.

The tighter they are, the less the mast wants to bend, which will help transfer backstay tension to the forestay but will make it harder to flatten the main with mast bend.

The optimum setting will depend on your sails and the conditions.

Check the mast is straight

With the fore and aft bend set, check the mast is still in column side to side.

Hopefully it will be, but if it isn’t, use the lowers and intermediates to true it up.

On a single spreader rig the aft lowers are usually the best tool for this, but if the bend is significant you might need to relax the opposite forward lower, if there is one, to allow the mast to move.

If you do, make sure you retain the fore and aft bend, and keep checking the tensions in all the lowers to keep them as even as possible.

With the bend set and the mast straight, go back and check the tension in the cap shrouds.

It may have reduced with the mast bend, in which case bring it back up to your desired tension.

Tension the backstay

With the rig basically set up, tension the backstay bottlescrews to your minimum working tension.

I set ours to about 7% of the wire load, with application of the tensioner taking it up to around 17%.

Even on a stiff masthead rig like ours, this compresses the mast enough to introduce significantly more bend, and more importantly for us dramatically increases forestay tension.

With a backstay bridle like this, check the tension above the joining plate

If you don’t use a backstay adjuster, set the backstay to a similar tension to that of the cap shrouds, then go forward and check the forestay.

The tension should be similar, and will help with your upwind performance.

The above will give you a good initial set-up, but there’s no substitute for seeing how it behaves under sail.

Head out in a moderate breeze, put the boat on the wind and hand over the helm to someone else.

Then check your leeward cap shrouds.

They should still be taut in these conditions – if they aren’t, you need more rig tension.

In a moderate breeze, the leeward shrouds should stay taut

Next, sight up the mast to check it is still in column. If the middle sags to leeward, tighten the lowers.

If the tip sags off it could be the middle popping to windward or the tip sagging.

Both over-tight lowers and loose cap shrouds will have this effect, and it can be dangerous as it reduces the angle at which the cap shroud meets the masthead, making its support less effective.

If you have this problem, check your tension settings before making a decision which to alter.

Rig tuning: conclusion

A well-tuned rig makes a boat sail better, while ensuring your mast is correctly supported is a safety essential.

As mentioned at the beginning of this article, boats move, so although you should be able to leave your mast rake and side-to-side centring alone, keep an eye on the shroud tensions.

They may well reduce, especially in the first weeks after setting up the rig, so don’t assume that all is well.

You keep an eye on your engine levels – five minutes with a tension gauge or a wander around the deck under sail will do the same for your rig

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Last month we started looking at sailboat rigging ( Sail Rig Inspection – A Quick How To ), namely how to inspect it to ensure that you enjoy your days on the water worry-free. Once sure that the rig is sound, you can focus on making it perform, and that’s where we pick up this month – sail rig tuning.

A Quick How To on Sail Rig Tuning

A complete sail rig tune involves a static tune at the dock AND a dynamic tune under sail.

How to do the Static Sail Rig Tuning

The static tune ensures everything is straight and true, while the dynamic sail rig tune sets it all up while the boat is under load.

TIP: Always grease and mark turnbuckle threads before adjusting them (to lubricate and establish a starting point).

At the dock, de-tune the athwartships shrouds – slacken upper shrouds more than the lowers. If the yacht has a backstay adjuster, ease it off completely.

Ensure that the mast is standing true by running a metal measuring tape up the sail track with a spare sail slide – from the masthead, measure down to the port and starboard chainplates. If the measurements aren’t equal, carefully adjust the upper shrouds to tilt the mast to port or starboard.

By hand, take up the shrouds symmetrically, uppers first. Sight up the mast track after each adjustment to ensure the mast remains ‘in column,’ without any bends. It’s amazing how accurate your eyes are in this case – trust them. A bend to port at the spreaders, for example, requires more tension on the starboard lower shroud, less on the port.

With large wrenches, carefully tighten the turnbuckles (again, symmetrically, uppers first) to the working shroud tensions. Uppers should be tightest – lowers and intermediates slightly less so. Always use the same arm when checking tension – touch is sensitive enough to notice an unbalance. An over-tensioned rig can indeed bend a fiberglass hull, so be conservative.

How to do the Dynamic Sail Rig Tuning

For the dynamic tune, sail close-hauled in a moderate breeze (12-18 kts). The leeward shrouds should be loose but not slack. Snug them up by hand (count your turns), then tack and do the same on the other side. The mast should remain in column throughout – new bends are best resolved back at the dock.

TIP: Backstay tension determines headstay tension – the jib luff should not have more than 12-18 inches of ‘deflection’ off centerline (most furlers will not furl smoothly if there is any more).

Secure each turnbuckle with new cotter pins, and re-check the rig each time you sail.

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Boat Clinic: Tuning the Masthead Rig

My father was a rarity: he really did not care at all how well the boats he sailed performed. Perhaps this was because, in his youth and young manhood, he had been both a tremendously aggressive and a wonderfully successful athlete and thus had wrung out his competitive needs.

Tuning the rig of a boat is one of the necessary -and pleasant -tasks which must be done to achieve good performance. In an untuned boat, the mast bends in odd ways, and this in turn causes the sails to set badly. By contrast, on a well tuned boat , the rig bends in a controlled fashion, allowing the sails to do their best. For this reason, an avid racer will be constantly fiddling with the tune of his boat, while for most of us a one time job during commissioning may suffice.

The first thing to realize is that for a mast to stand well, it should not be straight when in a static, no load situation. This was something I realized nearly thirty years ago when conventional advice was to tune rigs so that masts were indeed straight when static, and while that advice is still sometimes given, most of the sailing world has realized that a controlled static bend is needed.

The problem with a statically straight mast is that when loaded, it is too easy for the mast to invert, or bend backwards. This can happen when the boat is beating in a seaway or reaching with the spinnaker pole up. Most mast sections can accommodate a significant amount of forward bend without failure, but very little aft bend.

An afternoon spent on a poorly tuned boat a couple of seasons ago left me a nervous wreck. Each time the boat came off a wave the mast pumped and wriggled so much that you could see it changing shape from the tiller. The owner, happy man, was ignorant and oblivious to the danger of losing his rig.

In contrast, if you set up the rig so that it has “prebend”, that is, the center of the mast bends forward when in a static condition, the loaded mast will flex in the proper direction. What flex there is will then tend to flatten the main, rather than bagging it, and the boat should balance better, particularly in heavy air, when most boats start to develop helm problems.

The first job is to get the mast straight athwartships. Leave the lower shrouds hand slack during this procedure. Use the main halyard as a measurer. Take the shackle end of the halyard a measured distance aft of the bow along the gunwale, then have someone take up the slack while you hold the shackle firmly to that point. Cleat off the halyard.

Then take the end of the halyard to the same point on the other side of the boat. If the mast is straight athwartships, the halyard shackle will just kiss the same point on the gunwale on either side of the boat.

Because chainplates are rarely put on perfectly symmetrically on the two sides of the boat, it is best to go to the trouble to measure back from the stemhead on each side for your reference mark, rather than using the chainplates as the reference.

If the halyard doesn’t touch the same point on both sides of the boat, adjust the cap shrouds (upper shrouds) until the mast is straight. Be sure to loosen one side as you tighten the other, and sight up the mast to make sure that you haven’t put any sideways bend in. The sailtrack should be straight athwartships when you sight up the mast, unless it has been put on crooked.

It should be noted that if your deck is slightly crooked -a fairly common problem the mast may not be perfectly centered athwartships in the partners when it is vertical to the hull.

Don’t attempt to make the mast vertical by putting a level on the side of the mast. Almost no boat floats without a list to one side or the other, and your weight alone is enough to put a slight list on a surprisingly large boat.

At this point, on boats up to about 35’, the cap shroud turnbuckles should be hand tight. What’s hand tight? Just what it says: as tight as you can get a well-lubricated turnbuckle with your bare hands. Later, when testing under sail, you’ll find the leeward shrouds slopping around by a few inches; then, and only then, you can take the slack out of the leeward shrouds. If you have absolutely no slack in the leeward capshroud when the boat is going upwind in 1.2 knots of wind, the shrouds are probably too tight for most boats.

Next set the rake of the mast using the fore and back stays, again only hand tight. If you don’t know from experience what the proper rake should be, begin with a modest rake of no more than the fore and aft diameter of the mast. Use the main halyard as a plumb bob. Later you may wish to modify this rake. Utilize the facts that increasing mast rake and/or moving the mast aft increase weather helm,-while decreasing mast rake and/or moving the mast forward decrease weather helm.

Now that the mast is properly straight athwartships and properly raked, it’s time to start the controlled bends. These are accomplished with the forward lowers, babystay, backstay, and mast wedges. Whether your boat has double forward lowers or a single, centerline babystay doesn’t matter. Both systems accomplish the same end.

First, take up the babystay or double forwards until you’ve pulled a forward bend of 1/2” to 1” into the middle section of the mast. Again use the main halyard -this time pulled tight against the lower, aft edge of the mast -as a measuring reference. If using double lowers, make sure the mast remains straight athwartships.

Next crank up on the backstay until you’ve got a curve in the mast equal to 1/2 to 1 times the fore and aft dimensions of the mast. Finally, take up the aft lowers hand tight.

If your mast is stepped on the keel you need at this point to wedge it at the partners. Wooden wedges are easiest to make, but they can dent an aluminum mast if the shrouds are set so loosely that the mast leans to leeward significantly when sailing upwind. A fairly firm rubber wedge works better with looser rigs, and is probably the safest to use. Rubber wedges are usually harder to make, however.

Your boatyard or chandlery may sell special rubber for mast wedges. If not, try to buy something in the nature of thick inner tubing. In a real pinch, sections cut from old auto tires will do, but will have to be rasped to thickness. Don’t use a foam material; it’s too soft. You’ll need two wedges, one fore, one aft. The width of each should be about 35 % to 40% of the mast’s circumference. Thus, they’ll curve around both the front and sides of the mast. Since the rubber wedges must be under compression, their thickness should be slightly greater than the gap they need to fill. You may have to cement together several layers of thin rubber to achieve the proper thicknesses.

The first step in wedging is to trim the wedges so they do not push the mast out of column sideways. As noted earlier, many decks are slightly off center, so there may not be equal space on both sides of the mast, even when it is in the proper position.

When the wedges are properly trimmed for the sides of the partners, you are ready to insert the aft wedge. To support the prebend, put a line around the mast a foot or so above the partners, and run it forward to a fixed point -a snatch block on a mooring cleat or a bridle between the cleats -then aft to a cockpit winch. Now slip the aft wedge into place. Release the load on the line, and insert the forward wedge. A little soap on the wedge will ease a tight fit.

Now you’re ready for a sailing trial.

Choose a day when you can comfortably carry a genoa. About eight to 1 5 knots of wind will do for most boats.

Put the boat hard and full on the wind and check the mast. It should be retaining the same fore and aft curve you put in while tuning. If not, adjust the babystay or forward lower shrouds. Next check the athwartships shape of the mast. It should be straight. Any necessary adjustments should be carried out with the leeward shrouds, then the boat should be tacked to check the effect of the adjustments.

If the mast is straight athwartships, tack and hand tighten all the leeward shrouds by an equal number of turns. If the center of the mast bends to weather, tighten the capshrouds more than the lowers. If the center of the mast sags to leeward, tighten the lower shrouds more than the cap-shrouds.

You should also check the athwart-ships bend of the mast in varying wind strengths, adjusting the aft lowers until you’ve achieved the best compromise between a straight mast and one which falls off or hooks. A masthead which hooks to windward should be avoided.

When, after a few sailing trials, you’re satisfied, pin the turnbuckles, then tape everything that could catch a sail or sheet.

We’ve dealt with what might be called traditionally rigged masts, those with spreaders which sprout essentially at right angles to the mast. Nothing we’ve said, however, isn’t also true of fractional rigs with aft raked spreaders. The only difference is that on such a rig the cap shrouds, as they load up, work on the spreaders to increase forward mast bend, but that’s all to the better.

– J. Pazereskis

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Rig Sails: A Comprehensive Guide to Sailboat Rigging

by Emma Sullivan | Aug 19, 2023 | Sailboat Gear and Equipment

Short answer: rig sails

Rig sails refer to the various types of sails used in sailing rigs. They include mainsails, jibs, spinnakers, genoas, and more. Rig sails play a crucial role in harnessing wind power to propel boats and are designed for different wind conditions and sailing purposes.

How to Rig Sails: A Step-by-Step Guide for Beginners

Title: Mastering the Art of Rigging Sails: A Step-by-Step Guide for Novice Sailors

Introduction: Sailing, with its mystique and undeniable allure, has been captivating hearts for centuries. As a beginner sailor, understanding the process of rigging sails may seem like venturing into uncharted waters. Fear not! In this comprehensive guide, we will take you through the ins and outs of sail rigging, ensuring smooth sailing experiences ahead.

1. Unveiling the Anatomy of a Sailboat: Before delving into rigging sails, it is essential to familiarize yourself with the fundamental components of a sailboat . From mast to boom, stays to shrouds, each part plays a crucial role in successfully setting up your sails for optimum performance .

2. The Art of Preparation: Preparing your sailboat before embarking on your adventure is akin to an artist priming their canvas before creating a masterpiece. This section covers key pre-rigging steps such as inspecting your equipment for wear and tear, verifying weather conditions, and readying necessary tools.

3. Setting Up the Mast: The mast serves as the backbone of your sailboat’s rigging system. We will guide you through erecting and securing this towering structure with precision and ease while emphasizing safety measures that should never be overlooked.

4. Attaching Shrouds and Stays: Once the mast is securely in place, attaching shrouds (cables supporting vertical stability) and stays (supporting lateral stability) work together harmoniously to maintain balance during sailing maneuvers. Our step-by-step instructions ensure these crucial elements are properly adjusted for optimal sail performance .

5. Hoisting Your Sails Before Hoisting Anchor: This exciting moment marks when all previous efforts culminate into tangible forward momentum on water! Guided by our expert advice, we’ll walk you through hoisting main sails or jibs sequentially while highlighting commonly overlooked details that impact sail trim and efficiency.

6. Fine-tuning Sail Trim: As any seasoned sailor will attest, the art of sail trim can transform a seemingly average voyage into an exhilarating, breeze-filled escapade. Gain insights into adjusting sail controls, such as halyards and sheets, to optimize sailing performance in various wind conditions.

7. Navigating Nautical Knots: A sailor’s toolkit is incomplete without proficiency in tying essential knots . In this segment, we’ll showcase a selection of nautical hitching marvels, from the versatile bowline to the secure figure-eight knot . Master these knot-tying skills for security and confidence when rigging sails .

8. Deploying Safety Measures: While embracing the excitement of setting out on your sailing adventure, it is paramount to prioritize safety precautions that protect you and your crew on the water. We’ll share vital tips regarding life jacket usage, weather awareness, emergency protocols, and more.

9. Practice Makes Perfect: Troubleshooting Common Issues: Even with meticulous planning and execution during sail rigging, occasional mishaps may occur while on the water. Fear not; this section unravels common troubleshooting scenarios a novice might face along their journey while providing practical solutions to keep any minor setbacks from dampening spirits.

Conclusion: With this all-encompassing guide to rigging sails designed exclusively for beginners like you, embark on your maiden voyage with confidence! By understanding each step intricately and embracing best practices in safety and knot-tying techniques, you’ll master the art of rigging sails—a critical stepping stone towards becoming an adept sailor capable of navigating endless seascapes with grace. So hoist those sails high as you venture forth into a world brimming with endless possibilities—it’s time to set sail!

Mastering the Art of Rigging Sails: A Comprehensive FAQ

Are you ready to take your sailing skills to the next level? Look no further! In this comprehensive FAQ, we will dive into everything you need to know about mastering the art of rigging sails . From understanding the different types of rigging systems to troubleshooting common issues, we’ve got you covered. So grab a cup of coffee and let’s set sail on this knowledge-filled adventure !

1. What is Rigging and Why is it Important? Rigging refers to the system of ropes, wires, and other devices used to support and control the sails on a boat . It plays a vital role in harnessing the wind’s power effectively, allowing sailors to maneuver their vessels with precision. Proper rigging ensures optimal sail shape, enhances speed and stability, and improves overall performance on the water.

2. Different Types of Rigging Systems There are several types of rigging systems commonly used in sailing:

– Fractional Rig: This type employs a forestay that attaches below the masthead, making it highly versatile for various wind conditions. – Masthead Rig: In this traditional rig setup, both the headstay and backstay attach at the top of the mast. – Cat-Rigged: A single mast positioned well forward in the boat characterizes cat-rigged vessels . – Slutter Rig: Combining elements from both sloop and cutter rigs, slutter rigs use more than one headstay.

Understanding these different rig configurations allows sailors to choose what best suits their intended use and sailing conditions.

3. Essential Knots for Sail Rigging Knot tying is an essential skill for any sailor . Here are a few crucial knots for sail rigging:

– Bowline Knot: This versatile knot creates a secure loop that won’t slip under load. – Cleat Hitch: Used for securing lines onto cleats without tying knots . – Reef Knot: Ideal for tying two ends of a line together, especially when reefing sails . – Taut-Line Hitch: Perfect for adjusting the tension of a line under load.

Mastery of these knots will make sail rigging both efficient and effective.

4. Troubleshooting Common Rigging Issues Rigging problems can arise even for seasoned sailors. Here are some common issues you may encounter and how to tackle them:

– Excessive Mast Bend: This can lead to inefficient sail shape. Adjust the backstay tension to correct it. – Loose Shroud or Stay: A loose shroud affects mast stability and ultimately, sail performance. Tighten the appropriate stay using a turnbuckle or other tensioning mechanisms. – Slipping Halyards: Prevent halyards (ropes used to raise sails) from slipping by tying a stopper knot at the end. – Snapped Masthead Sheave: Replace the damaged sheave with a similar-sized one before it compromises your sailing experience .

Remember that regular inspections and maintenance are crucial for preventing major rigging mishaps.

5. Tips for Efficient Sail Rigging To maximize your sail rigging efficiency, consider these valuable tips:

– Label Your Lines: Invest time in labeling your lines according to their function or purpose; this saves time during set-up or troubleshooting. – Use High-Quality Hardware: Investing in top-notch pulleys, blocks, and shackles ensures reliability during critical moments on the water . – Practice Kaizen Methodology: Continuously seek small improvements in your rigging setup over time to enhance overall system performance gradually.

By adhering to these tips, you’ll be well on your way to becoming a seasoned sailor who consistently achieves peak rigging proficiency.

Mastering the art of rigging sails is an exciting journey filled with endless learning opportunities. Understanding different types of rigs, essential knots, and troubleshooting common issues will empower you as a sailor. Remember to prioritize regular maintenance, practice efficient rigging techniques, and continuously seek improvement. So go ahead, hoist your sails, catch the wind, and embark on unforgettable nautical adventures !

Exploring the Different Types of Rig Sails: Which One is Right for You?

Title: Exploring the Different Types of Rig Sails: Which One is Right for You?

Introduction: When it comes to sailing, one crucial element that determines the performance and maneuverability of your boat is its rig sails. Designed to harness the power of the wind, rig sails come in various types, each offering unique characteristics and advantages. In this blog post, we will delve into the different types of rig sails available, helping you navigate through your options and choose the perfect one for your sailing needs.

1. The Classic Mainsail: Starting off with a timeless choice, the classic mainsail remains a popular option due to its versatility and easy handling. Its triangular shape offers excellent efficiency in directional stability and steering upwind. This traditional sail design allows sailors to adjust settings swiftly in response to changing wind conditions, making it ideal for both cruising enthusiasts and racing warriors alike.

2. The Genoa: For those seeking enhanced speed and performance, look no further than the genoa sail. As an overlapping headsail that extends beyond the mast’s leading edge, this type of sail maximizes surface area exposed to wind pressure, translating into increased momentum while sailing close-hauled or reaching. With impressive light-air capabilities and superb pointing ability when partially reefed, genoas are a favorite among competitive sailors chasing buoy-to-buoy supremacy.

3. The Jib: Similar to a genoa but with less overlap on the mast’s leading edge, jibs find favor among sailors seeking greater balance between speed and manageability. Their reduced surface area generates reasonable power without compromising control during gusty conditions or tighter maneuvers . Overall, jibs make excellent companions for cruisers embarking on long journeys where varying wind conditions may be encountered.

4. The Spinnaker: Enterprising thrill-seekers looking to catch downwind winds with flair will undoubtedly appreciate spinnakers’ gossamer elegance and exhilarating potential for acceleration. Often employed during downwind sailing or racing, these large, billowing sails can capture even the slightest zephyr, propelling your boat to impressive speeds. Spinnakers come in a wide range of cuts and sizes, from traditional symmetrical designs to asymmetrical versions that simplify handling for solo sailors.

5. The Code Zero: When it comes to reaching faster than the wind itself or making significant headway at low wind angles, using a Code Zero sail is an ingenious choice . This specialized sail combines the characteristics of both a genoa and a spinnaker, tingling your competitive instincts with remarkable speed possibilities in light air conditions. Its projecting bow-sprit allows effective sheeting angles and creates lift while minimizing drag, ensuring you triumph over calmer waters .

Conclusion: Choosing the right rig sails involves assessing various factors such as your sailing style preferences, your boat’s design and size, and the prevailing weather conditions you typically encounter. Whether you opt for the time-honored mainsail or revel in the adrenaline rush provided by spinnakers or Code Zero sails, understanding their strengths will enable you to select the most suitable sail for maximum performance on your voyages. So weigh anchor , hoist your chosen rig sail high and confidently set course towards endless nautical adventures!

Pro Tips and Tricks for Efficiently Rigging Sails to Enhance Performance

As sailing enthusiasts, we understand the importance of harnessing the power of the wind to maximize performance on the water. Rigging your sails efficiently is not only key to enhancing your boat’s speed, but it also improves maneuverability and overall control. In this blog post, we’ll delve into some professional, witty, and clever tips and tricks that will take your sail rigging skills to the next level.

1. Choose the right materials: The choice of materials for your sail rigging can greatly affect its performance . Opt for high-quality lines that ensure minimal stretch, such as Dyneema or Spectra. These are not only lightweight but also provide excellent strength and durability.

2. Tension is everything: Proper tensioning of your rigging lines is crucial for optimal sail shape and control. Too loose, and you risk losing power; too tight, and you may hinder maneuverability. Experiment with different tensions until you find the sweet spot that maximizes both speed and responsiveness.

3. Know your angles: Understanding how wind interacts with your sails at different angles is a game-changer in sail rigging efficiency. Adjusting your sheets based on wind direction allows you to fine-tune sail shape and trim effectively. Keep in mind that small tweaks make a big difference!

4. Balance is key: Achieving a balanced rig ensures that the forces acting on your boat are evenly distributed across all sails . This minimizes excess heel or weather helm discrepancies, resulting in better control and improved performance. Invest time in adjusting shrouds, stays, and halyards to achieve perfect balance.

5. Be mindful of weight distribution: A well-balanced boat not only requires proper rig tuning but also careful attention to weight distribution onboard – including crew positioning! Storing heavy gear low in the boat reduces unnecessary drag while maintaining stability.

6. Take advantage of sail controls: Utilize cunningham, outhauls, and leech lines to fine-tune your sails’ shape under different wind conditions. These control mechanisms allow for quick adjustments on the fly, ensuring that your sails are always optimized for performance .

7. Innovative gadgets: The sailing world is never short of clever gadgets designed to enhance rigging efficiency. Explore options like mast-mounted cameras or sensors that provide real-time feedback on sail shape and trim , allowing you to adjust and optimize accordingly.

8. Seek professional guidance: Investing in a professional rigging tune-up can significantly improve your sailing experience . Knowledgeable professionals can help identify any issues with your setup or offer expert advice tailored to your specific boat and needs.

9. Embrace trial and error: Sailing is a lifelong learning process, so don’t be afraid to experiment! Rigging sails efficiently often requires tinkering and making adjustments until you find the perfect setup for your vessel. Each boat is unique, so embrace the journey of finding what works best for you.

10. Have fun! While rigging sails may seem like a technical chore at times, it’s important to remember why we love sailing – the sheer joy of being out on the water! So don’t forget to enjoy the process, celebrate even small improvements in performance, and share a laugh with fellow sailors along the way.

By incorporating these pro tips and tricks into your sail rigging routine, you’ll not only enhance your boat’s performance but also deepen your understanding of the art of sailing. So grab those lines, hop aboard, and let the wind carry you towards newfound speed and excitement!

Common Mistakes to Avoid When Rigging Sails and How to Fix Them

Rigging sails may seem like a straightforward task, but even the most seasoned sailors can make mistakes that result in compromised performance or even safety hazards on the water. In this blog post, we will highlight some common mistakes to avoid when rigging sails and provide you with effective solutions to fix them. Get ready to set sail with confidence!

1. Insufficient Tension: One of the most common mistakes is failing to achieve sufficient tension in your sails. A poorly tensioned sail can lead to reduced speed , unstable handling, and decreased control over your vessel. To fix this issue, invest in a reliable tension gauge specifically designed for sailboat rigging. Follow manufacturer recommendations to ensure the ideal tension for your particular sails.

2. Misaligned Mast: A misaligned mast is another frequent mistake that can affect sail efficiency . Ensure that your mast is properly aligned both horizontally and vertically before setting off on your sailing adventure . Utilize a spirit level and adjust accordingly until it aligns perfectly perpendicular to the deck.

3. Incorrect Halyard Tension: Neglecting proper halyard tension can cause unwanted wrinkles or excessive sagging in your sails, hampering their performance significantly. Take the time to understand the specific requirements of each type of halyard on your boat and adjust them accordingly during rigging for optimal performance.

4. Mismatched Sail Shape: Using a mismatched or improperly trimmed sail shape is a grave error that can hinder sailing efficiency greatly. Invest time in learning how different types of sails should be shaped and trimmed based on wind conditions and points of sail (such as upwind or downwind). Regularly adjust trim settings while observing telltales for indications of efficient airflow over the surface of the sail .

5. Inadequate Sheet Length: If you find yourself struggling to trim or control your sails due to inadequate sheet length (rope used to control the angle), it’s time for an upgrade. Ensure that your sheet length accommodates the full range of sail adjustment required during various wind conditions and sailing angles. Purchase longer sheets or consider installing a suitable purchase system to ensure optimal control.

6. Disorganized Running Rigging: A cluttered or disorganized running rigging setup not only makes it difficult to operate smoothly but can also lead to tangled lines or malfunctioning hardware. Take the time to neatly organize and label your lines, ensuring easy identification and a streamlined operation on deck.

7. Neglected Standing Rigging Inspection: Over time, wear and tear can weaken standing rigging components such as shrouds and stays. Neglecting routine inspections can result in unexpected failures that jeopardize both crew safety and equipment integrity. Regularly inspect all standing rigging elements for signs of damage, corrosion, or fatigue; replace any suspect parts promptly before undertaking any voyages.

By avoiding these common mistakes and addressing them properly with the provided solutions, you’ll be well on your way to optimizing your sailboat’s performance while maintaining safety on the water. Remember, attention to detail and continuous learning are key when it comes to rigging sails effectively – so embrace the challenge and set sail with confidence!

The Ultimate Cheat Sheet for Troubleshooting Your Rigging Sails

Title: The Ultimate Cheat Sheet for Troubleshooting Your Rigging Sails: Unveiling the Secrets of Smooth Sailing

Introduction:

Setting sail and gliding through the open waves with your trusty vessel is an exhilarating experience every sailor craves. However, sailing bliss can quickly turn into a nightmare if your rigging sails encounter problems along the way. Whether you’re a seasoned sailor or just starting out in this adventure, our ultimate cheat sheet will equip you with insightful tips and tricks to troubleshoot rigging sail issues like a true professional. So, gather around fellow sailors, as we embark on this journey to uncover the secrets of smooth sailing !

1. Unraveling the Mysteries of Mast and Boom Alignment:

One crucial aspect of troubleshooting your rigging sails lies in ensuring proper alignment between the mast and boom. Misalignment can result in inefficient performance and even potential damage to your entire rigging system. To tackle this issue effectively: – Start by examining all fittings and connections thoroughly. – Verify that linear alignment is maintained when viewed from multiple angles. – Utilize a tension gauge to achieve optimal tension across the shrouds and stays.

2. Nipping It in the Bud: Dealing with Frayed or Damaged Lines:

Frayed or damaged lines are not only visually unappealing but also compromise their strength, putting your sails at risk during strong winds or sudden maneuvers. By following these steps, you can address this common problem head-on: – Regularly inspect all lines for signs of wear such as fraying, cuts, or thinning sections. – Replace any compromised lines immediately to ensure maximum safety. – Opt for high-quality materials resistant to UV rays and wear-and-tear for durability.

3. Grave Dangers Lurking Aloft: Identifying Issues with Standing Rigging:

The standing rigging plays a vital role in providing stability and support to your sails while underway. Spotting potential issues affecting the standing rigging can save you from catastrophic failures out on the water: – Conduct a comprehensive visual inspection, looking for signs of rust, corrosion, or deformities in key components. – Assess the tension of your shrouds and stays, making adjustments as required to maintain proper tuning. – Seek professional assistance if you encounter severe structural concerns to avoid compromising safety.

4. Untangling Snaggy Situations: Resolving Halyard Hang-Ups:

There are few things more frustrating than a halyard getting tangled or jamming at the most inconvenient moments. Here’s how to steer clear of such snags: – Regularly inspect halyards for signs of fraying or wear near sheaves and exits points. – Lubricate moving parts with quality marine-grade lubricants to ensure smooth halyard movement. – Install external organizers or fairleads where needed to guide halyards away from obstructions.

Conclusion:

Nailing down the art of troubleshooting your rigging sails is the key to achieving uninterrupted adventures on the open seas. By following this ultimate cheat sheet, you can confidently face common issues head-on and navigate through unexpected challenges like a seasoned sailor. Remember, diligence in maintenance and a deep understanding of your rigging system will unlock a world of safe and unforgettable sailing experiences. So tighten those lines, set sail with confidence, and let the wind carry you towards new horizons!

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How to Tune a Sailboat Mast

Here are some general guidelines for tuning your mast’s standing rigging . please see our blog on  how to properly adjust a turnbuckle  before you begin. as always we recommend seeking the advice of a professional rigger for more specific tips and tricks regarding tuning your boat’s rigging..

Your boat must be in the water. Begin by just slacking off all of the side shrouds as evenly as possible, so that all stays can be adjusted by hand. Once loose, try and adjust all turnbuckles so that they are pretty much equally open (or closed) from port to starboard respectfully. Also go ahead and line up the cotter pin holes (if present) in the studs so that they are in a pin-able position. Now is also the time to balance out the threads, between the upper and lower studs of the turnbuckle, IF they are not even. Do this by unpinning the turnbuckle from the chainplate – BE CAREFUL HERE –  to ensure the mast is secure before unpinning any one stay. Lastly, loosen all halyards or anything that may pull the mast to port, starboard, forward or aft.

1.  Check by sighting up the backside of the mast to see how straight your spar is side to side. You can take a masthead halyard from side to side to ensure that the masthead is on center. Do this by placing a wrap of tape 3′ up from the upper chainplate pin hole on each upper shroud. Cleat the halyard and pull it to the tape mark on one side, mark the halyard where it intersects the tape on the shroud. Now do this to the other side, the mark on the halyard should also intersect the tape similarly. Please note: when the mast is equipped with port and starboard sheaves, instead of just one center-line sheave, it will appear slightly off to one side. Just keep this in mind……

2.  Using the upper shrouds as controls, center the masthead as much as possible using hand tension only. Some masts are just crooked. If yours is(are) crooked, it will reveal itself when you loosen all of the stays and halyards initially and sight up the mast. Although you should use hand tension only, you can use a wrench to hold the standing portion (the stay portion) of the turnbuckle. If for some reason the shroud is totally slack and you still can’t turn the turnbuckle by hand then the turnbuckle may need to be serviced, inspected, and maybe replaced.

3.  Tune the mast from the top shroud on-down, making sure the mast is in column.  Remember:   as you tension one shroud by adjusting the turnbuckle, to loosen the opposing shroud the same amount.

4.  Once the mast is fairly straight from side to side, tighten the shrouds all evenly using tools for tensioning. Typically, for proper tension, the shrouds should be tightened using these guidelines; uppers are the tightest, and then fwd. lowers, then the aft lowers and intermediates should be hand tight plus just a turn or two. ~ With an in-mast furler it is recommended to tension the aft lower a bit more to promote a straighter spar (fore and aft) for better furling. 

5.  Now you can tension the aft most backstay (s). If the backstay has an adjuster it should be set at a base setting (500-1000 lbs). If the backstay simply has a turnbuckle then it should be tightened well. After this has been done, in either situation (adjustable or static backstay), one should site up the mast from a-beam and notice that the masthead has a ‘slight’ aft bias. If there is no aft bias, too much, or the mast is inverted (leaning forward), then the forward most forestay (s) will most likely need to be adjusted to correct this. If a furler is present then seek the council of a professional rigger or refer to your furler’s manual for instructions on how to access the turnbuckle if there is one present.

6.   Finally, sight up the mast one last time and make any necessary adjustments.  

7.  MAKE SURE ALL TURNBUCKLES AND PINS HAVE  COTTER PINS AND ARE TAPED NEATLY  TO PREVENT CHAFE!

Read HERE for how to use a LOOS & Co. Tension Gauge!

Here is a little vid from our friend Scott at  Selden Masts  (click the link then hints and advice for more info) on rig tune…..

[youtube http://www.youtube.com/watch?v=rcCALZ4x6R4&w=420&h=315]

Is your mast fractionally rigged, only has a single set of lowers or is just plain different? Be sure to leave any  questions or comments below.

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54 Comments

I have a 1965 Alberg 30. On a starboard tack the boat has more weather helm than on a port tack. I have not been able to achieve a balanced helm on either tack. New full batten main, new 150 roller furl genoa.

Other than the boat being evenly ballasted from port to starboard, e.g. holding tanks, fuel tanks, below deck furnishings, and storage items, I would check the rig from side to side. A crooked mast or poor static tune can result in the boat sailing differently on both tacks. A good way to test this is either sighting up the mast at the dock to ensure that the mast is relatively straight side to side and in column. You can also see that when beating (aka hard on the wind), you have to make adjustment’s to the mainsail sheet tension (NOTE: the traveler will likely need to be adjusted to mirror the same setting as on the previous tack). If notice that with the traveler in the same position on each respective tack that the sail is bubbling or flogging more on one tack than on the other, it is likely necessary to re-tune the mast. This can be done at the dock by following the guidelines in the article once the everything has been appropriately loosened to tension.

Let us know if this helps.

Any Hints, tips for tuning a 1977 Whitby 27 sloop 1/4 ton rig?

Nothing special that I can think of. Just follow the guidelines in the article. From what I can gather there are only a single set of lowers correct? Are the spreaders aft swept at all or just straight out? If it is single lowers and no sweep to the spreaders you’ll need to set the rake using the forestay adjustment to set the rake and the backstay to control the forestay tension. If you are interested in optimizing sail tuning, like in racing situations: higher wind sailing conditions will desire more tension on the shrouds, a bit more tension on the lower than the upper, but only slightly; and in lighter winds loosen them up a bit, a tad looser on the lower than the upper.

Hope that helps, and good luck.

How do I tune /2 in rigging. Neither of the loos gaug s are large enough?

Thanks for the question. Yes, I think the Loos gauges only go up to 3/8″ wire. First let me say that a tension gauge is not a must for proper tuning, more for tension recording and also not exceeding max tension which is typically hard to achieve without additional fulcrums or wrench extensions. Having said that, if you know that you need one simply search google for cable tensioning gauges. There are a few others like this one https://www.checkline.com/product/136-3E , pricing is not easily apparent and may be excessive for your needs.

My recommendation is that if you have a good local rigger have them do a static dock-side tune and perhaps sail-tune in the boat’s ideal conditions. Perhaps they can provide a tutorial on their process for you to be able to make rigging adjustments over time.

Hope that helps.

Hi. Nice article. I have a Mirage 27 (the Bob Perry design). It’s a masthead rig with single spreaders and the shrouds on each side come to the same chainplate. I have been tuning so that tension on the lower and uppers is the same and trying to set them so that (as you say) the leeward shrouds are just slightly slack. But how do I induce mast rake? I have a split backstay with a 6:1 purchase on the adjuster; should the mast have rake even with the adjuster off? or do I just haul on it? or should the tension on the inners and outers be different?

HI Michael,

You will need to lengthen the headstay and shorten the backstay. This can be done a few ways either with turnbuckle adjustment or actually shortening and lengthening cables, sometimes you can add or remove toggles also.

Hope that helps!

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I recently purchased a 1988 Catalina S&S 38 and experienced my first launch this season, including stepping the mast and tuning the rig. As we prepared, we found that the Cap Shroud and Intermediate Shroud were clamped together at the four spreader ends. The folks at the yard had never seen that, and I certainly didn’t know why it was there … possibly to keep the spreader ends and shrouds consistent? Anyway, as I am learning how to tune my rig, it seems to me that these clamps would prevent me from tuning the cap shroud and intermediate separately and correctly Thoughts? Should I remove them and re-tune the rig?

So it is a double spreader rig I take it? The upper shroud wire should run freely through the first spreader, or the closest one to the deck, and be clamped at the top spreader. The intermediate shroud wire should be clamped at the lower spreader.

Before stepping, if this was done correctly, both upper spreader and lower spreader should be clamped equal distance from the mast attachment point, when looking at the mast from port and starboard.

In other words, you should measure the distance from where the upper shroud attaches to the mast to the end of the upper spreader and it should be the same distance on the other side, port to starboard. Then the same goes for the intermediate shroud and the lower spreader. The upper shroud should run freely through the lower spreader although it is covered by the clamp, but not actually clamped at the lower spreader, j ust the top one.

If all 4 spreaders are clamped equally port to starboard. You should be good to tune from there. The spreaders should show a slight up angle, to be specific slightly more up at the upper spreader than at the lower, but all of them should be just ever so slightly pointing up. You even want to think about clamping them slightly higher than that before tensioning, as this will pull them down and into their preferred angle, just slightly up. Specific angles are really only determined on the spar builders drawing and vary for manufacturer to manufacturer. Generally it is pretty clear where they want to sit. With the shrouds loose if you find that angle that appears to be the right one, and push them up slightly from there then clamp. This will allow them to be pulled down slightly once tensioned.

Kind of a tricky thing to explain in writing but hopefully it helps.

Have further questions? Give us a call 443-847-1004, or email us [email protected]

I have a Catalina 275 fractional rig with single swept back spreaders and an adjustable backstay. My questions are: how much rake, tension on cap and lower shrouds and on chain plate should cap shroud be forward and lower aft. I am racing and want the best performance. Thanks for any help. Bill

If the two shrouds are on the same plate, right next to each other, and the pin holes are the same diameter, and the plate is configured in a fore and aft configuration, I would choose the aft hole for the lower shroud and the forward one for the upper shroud.

In terms of specific rake, you will need to look towards the maker of your sails and or the boat manufacturer. I discuss how to measure rake in the preceding comments.

“You can measure rake by hanging a small mushroom anchor from the main halyard, with the boat floating on its lines, if you wish”

For racing I would start off with a good static tune at the dock by following the points in the article. If you know it’s going to be light day, start off with light rig tension. Be sure to use either Velcro wrap style cotter pins or simply lash the upper and lower shroud turnbuckles together to secure them. This will give you access to removing the pins or lashing while sailing and adjusting the stays.

From there you will need to sail tune for that days specific conditions, your shrouds will tell you what needs to be tighter and looser. I have answered how to do this a few times already in the comments below, please take your time to peruse the comments section to see what sail tuning entails. Doing this will always ensure that the cable tensions are set up ideally for the conditions and the boat can be sailed at maximum potential.

“For racing, ideally once the static tune at the dock (the part we just talked about) is done, go out and sail tune. Do this by going hard on the wind and checking to see if the leeward shrouds are just starting to dance, this is ideal. If they are swaying about they are too loose for the current conditions. If the leeward shrouds are tight, they may be a touch to tight. Tension and loosen as needed; count what you did and to what shroud, then tack and do the same to the other side.

ALWAYS secure the turnbuckles when you are finished adjusting them.”

Just hit ‘Ctrl F’ and search the page for “sail tune” and “rake”

I am trying to tune a Hallberg Rassy HR36 masthead rig. The rig has two in-line spreaders. The cap shroud is 3/8 inch and terminates at the lower spreader. From the lower spreader, the cable transitions to a 5/16 inch cable passing over the upper spreader to the masthead. A second 9/32 inch cable runs from the lower spreader to the mast (just below the upper spreader). The Selden rigging suggests that the “upper shroud” be at 15 percent of the breaking strength of the cable. In this situation, is it 15 percent of the 3/8 inch lower portion? If so, how should the upper 5/16 inch and 9/32 inch cables be tensioned?

Thanks for your help.

Hi Bryant, good question. Once proper alignment and centering of the spar has happened (static tune), and you are perhaps a hair tighter than hand tight on all shrouds, you can begin to tension things to a percentage of breaking strength. Do this by using the cables at the deck and use their diameters to determine the tensioning amount.

The V1 (aka cap shroud) in your case is a 3/8″ cable which supports the two cables above ii, hence its large diameter. The 5/16 V2,D3 and the 9/32 D2 total 19/32. So if 15% of the 3/8 cable is achieved you will below that threshold for the cables aloft. Does that make any sense?

With that in mind there is a range of acceptable tension from light air to heavy air. 15% sounds like a good middle of the road tension. Generally you do not want to exceed 30%. Sail tuning in ideal conditions is generally the best way to determine the right tension, but 15% of breaking strength sounds like a good place to start.

Don’t forget your cotter pins and tape, especially aloft.

Hope that helps and thanks for the question.

T.R.C. Thanks you for the clarification regarding the V2,D3 and D2 load distribution. When I set the V1 tension to 15%, the tension on the V2,D3 was at 8 %. I then tensioned the forward shroud to 12 % and the aft shroud to 10 %. Then I tensioned the backstay to 14 %. After doing this, I measured the tension on the V1 to be 10 %. The only information I could find regarding tension on the D2 was that is did not have to be tensioned much. I tensioned it to 5%. The mast sights straight and I used a bossen seat on a halyard to measure to the lower part of the V1, which also indicated that the mast was straight. Did I overtension the fore and aft stays? Is the tension in the D2 too much or too little? Again, I appreciate your advice.

When you tighten the backstay it usually induces a bit of aft bend in the mast which will soften the upper shroud (V1) a bit. You can just take up on it again to get it back to 15% if you like. As I said there is a acceptable range for all of the stays, which you are well within. Everything else sounds like you did a pretty good job. Next up sail tune and see if there is excessive waggling on the leeward side, but in moderate breeze. The shrouds will begin to sway as the breeze builds, this could be a telltale to either reduce sail a bit or you can add some tension to the shrouds all the way around.

Should be all good as they say.

Cheers, ~T.R.C.

T.R.C., your advice has been invaluable. I took her out in 12-15 knots and was very happy with the sail luff and stiffness of the rig. Thanks for you help!😁⚓️

Hi , can you provide any tuning guides for a Swan 38 Tall mast single spreader rig with baby stay, I am keen to set the rig up for new North sails and race her competitively. The mast is an exact Nautor factory replacement in 1998. She shall not have furling sails.

Hi Peter and thanks for the comment.

Unfortunately we do not have a guide for that boat. I would ask the sailmaker however to see what info he or she might have. Alternatively you can always start with a good static tune and then sail tune the boat as I describe in some of the comments below. This is the best way. I may use a Swan 45 Tuning guide as the template and then just fill in my own numbers over time. This is ideal, but infidelity start with asking the sailmaker you are working with, he should have some good info.

This may seem like a silly question, but it has me perplexed. How long should my cotter pins be? Long enough to ‘jam’ against the surrounding body, to prevent rotation? Otherwise, I don’t see how they’ll prevent my stays from loosening.

The length should be the minimum amount to just be able to bend the legs. Too long and they get caught up on things, too short and you can’t adequately bend the legs to keep the pin in place. The head of the pin is a actually providing the security.

Does that help?

Great article to get me started, thanks! I just have a few questions…

I originally owned a Tanzer 7.5. Her mast was rigid and simple to tune with a LOOS and an eyeball. I however now own a Mirage 33 (1982) and things are a bit more complex (but not too much). When I bought her the mast was already stepped and the owners said they replaced the forestay (inside the furler) 1 season ago. I went about the boat tuning the rig as best I could but I started second guessing the rake. I found noticeable rake in the mast with virtually no backstay tension on. So I think my forestay stretched (being “new”) and I need to bring it forward.

How do I measure how much rake (at rest on the tensioner) is enough? With my rig as is I felt worried that if I pulled down on the backstay tensioner I might buckle my mast by bending it too far. It seems to me it’s ALOT of downward pressure on the column when you pull down on her especially if the mast was already raked or maybe in my case leaned too far back to start? She has a babystay too, I wasn’t sure how far to tension that other than to assist adding bend\rake but since I had too much already I just lightly tightened it and hoped for the best!

Thanks for the question. With the backstay tensioner completely off, you should be able to adjust the static/ base tension of the backstay with a turnbuckle (s). Loosen the Baby Stay so that it is completely loose, sloppy, to take it out of the equation. Then mark furling line spool direction and remove the line. Next, open the furler up to gain access to the turnbuckle inside, if present. Remove all cotter pins or locking nuts to free the turnbuckles on the headstay and the backstay. You should then loosen things so that the headstay and the backstay can be adjusted by hand. Close the headstay turnbuckle and open the backstay turnbuckle to reduce rake, and vice versa if wanting to add rake.

You can measure rake by hanging a small mushroom anchor from the main halyard, with the boat floating on its lines, if you wish. Then once you achieve the desired mast rake go ahead and tension the forestay and backstay a few turns equally with tools; not too tight, but a good base light air setting, or as loose as you can imagine the headstay ever needing to be. Lastly, tension the baby stay a bit until it just starts to tug on the mast, helping induce bend. From here the backstay tensioner will do the rest: wind it on and it will tension the headstay and induce mast bend via the baby stay. You may have to take the boat sailing and adjust things as you find out how it performs at various degrees of rake and bend.

I hope that’s not too wordy, but helps explain it all a bit. Feel free to email or call with further questions.

Regards, ~T.R.C.

Can you provide some specific information regarding rig for 1980 C&C 32. Looking to purchase new main and want to get the most from it for Wednesday nights. Boat currently does not have a pony stay, it has been removed. Can replace that track/car. What should initial bend look like, keel step is fixed so assume I need to some chock aft of mast at deck? Have rod rigging but no Loos gauge for same, should I acquire one? Love this site, very helpful RayK

Thanks for the compliment. This may be less technical than you might expect. I would start with the basic guidelines given in the article to ensure a good base, static tune setting. A Loos gauge is good but not needed. If you focus on getting the spar straight, side to side, with a slight aft bias and then the tension is set so that it feels fairly tight. I know that sounds vague, but keep this in mind: if you are anticipating heavier wind make things a bit tighter, and loosen things up if less windy. The order of tension, in regards to the which shroud (upper vs intermediate vs lower) is important; more so than the amount of tension. Make sure nothing is so loose it is just flapping about.

The headstay should have some good slack to it with the backstay adjuster totally off. Adjust the backstay and headstay turnbuckles, with them in the slack position until the masthead is favoring a slight aft lean or rake, but only slight. From there, tension the backstay adjuster very tight and see what the headstay tension feels like, should be very tight.

PLEASE NOTE: if the backstay adjustment is totally bottomed out at this point, the backstay needs to be shortened a bit. Just pay attention to how this affects the rake. …

This part is where the pony stay or the baby stay will play a critical part, for mast bend. You may even find the pony stay to be good for mast pumping in light air and waves. Making this baby stay removable is a good idea, as well as, we’ve found that Dynema rope is the best choice here.

So… a centered mast head, side to side. A straight, in column mast from the top on down. A slight aft rake to start with…and as you begin to wind on the backstay and the baby stay you will add some rake but also a good bit more bend.

Take this set up for a few test sails and see how things act, in different conditions. After that you can make some adjustments here and there as needed: weather helm, shroud tension, mast rake, pre bend, etc…Moving chocks and using a Loos gauge.

ADDT’L TIP: Chocks and mast step position affect bend and rake properties. Want more rake? Chock mast aft in collar and move step forward. Want more bend? Chock mast forward in collar and move mast aft. As all things, there is more to it than that, but that’s the gist of the whole chocks and mast step thing…

“Sail Tuning” is a blog we are in the works of, but the punchline is that if hard on the breeze, and the leeward shrouds are excessively loose, and you are sure you aren’t over canvased…then go ahead and take turns on the leeward side until they just stop waggling, count what you’ve done, tack and mirror the turns on the other side.

Once the boat is set up for that specific condition, and you return to the dock, you should take your loose gauge and record these settings…creating a tension gauge setting for various conditions.

Hi, Thanks for your information. I have a Dehler 34. 1986… How much mast prebend and rake is recommended? The boat is new to me in March. Raced ok but I want to get a new main and want it to fit a well tuned mast. What do you think of a 2 degree rake and 4″ prebend at the speaders? Also, I have a Harken furler, How do you measure the forestay tension? Thanks, Duke

The answer, this boat is pretty sporty so it should show some rake. The spreaders are swept slightly aft so this will produce some natural bend just to tension the headstay.

Head-stays are always tough to measure with any sort of gauge, there are some class specific tricks for using a gauge in funky ways in order to get data, but they aren’t really reliable in my opinion. If you live in a typically windy area, go for bit more shroud tension, headstay tension and mast bend, and see how the boat feels. This will take some trial and error. If the forestay feels too stiff, slot too tight, loosen the uppers a bit, thus reducing bend and slackening the headstay.

Once the boat is sailing well in the ideal conditions, record that bend and those tensions. This is where I would leave things set, record it, and then just adjust shroud tension to affect bend and headstay in order to compliment different wind strengths and sea states. It takes quite a bit of back and forth, and documentation to get it right. One designers have already worked all of this out and then they share it for others…..very helpful. The rest of us will have to be the trailblazers for this type of information for other boat owners with the same (similar) boats to benefit.

Hope that helps, thanks for the kind words, and good luck. Once you figure things out post a link here for others with the same boat…..would be helpful.

Hello, Thanks for all of this great info. I just purchased a 37′ boat with a 3/4 fractional rig and a tapered mast. I was wondering if there were any special considerations when tuning the fractional rig? Currently the stays and shrouds are a little loose and can be wiggled (borderline flopping) by hand although the mast stands and is visually centered. (We are in SW Florida and the boat went through a direct hit by hurricane Irma like this and still stands tall!) Also is it advisable to increase shroud tension in small increments first on one side and then do the same on the opposing side? Thanks so much for any info

Hi Nathan. There are some thoughts, so fractional masts are usually fitted with aft swept shrouds and spreaders. If so, this means that the uppers also tension the headstay and create mast bend. The lowers then also act to reduce mast bend, so the tighter you make them you are actually reducing mast curve, thus powering the mainsail up. So be conscious of these two thoughts when tensioning the shrouds. The rest is fundamentally the same as the guide suggests. Loose or wiggling shrouds (excluding the scenario where we are talking about the leeward shrouds under sail), should be tightened. Doing things in increments is definitely a good idea.

Hope that helps. Thanks for the questions.

Thanks!! Now that you say that about the swept spreaders helping create mast bend it makes perfect sense. I had an ‘oh duh’ moment. I’ll probably err on the side of looser lower shrouds knowing if we need more power we can always tighten them up. Thank you again this helped immensely!

I want to buy a tension gage. Most familiar with Loos. But do I need Pt 1 or 2? (Pretty sure I don’t need 3 or Pro.) I have two rigs to tune: a 1972 Morgan 27 and a Catalina 22, I think 73 or thereabouts. The Morgan 27 is mine, fresh water for life, and 99.9% most likely factory wire. The Catalina 22 is a borrower in the Gulf, but pretty sure the owner has never tuned it. My problem is I can’t find the gage of wire for either standing rigging anywhere! Any help?

I think this one will do… https://sep.yimg.com/ca/I/yhst-70220623433298_2270_120385950 . The Morgan is likely 3/16″ wire and the Catalina is likely 5/32″, that’s an educated guess. Hope that helps.

I just purchased a 1980 C&C 40. I was told that I need to replace the rod rigging as it is “too old”. The mast is down and the rod rigging seems ok but I have not done any penetration testing. Does rod rigging need to be replaced due to age? Thanks Rigging Co.

Not replaced, but re-headed. This can mean that some stays need to be replaced as a whole, but not typically not the whole set. There are instances where you’ve almost replaced all of it anyways, so full replacement just makes sense. Other than those scenarios, full replacement is due after a certain mileage with rod…60,000 NM. Please keep in mind these standards are very general recommendations. It sounds like in your case, you should send in the rod, tangs, and chainplates for service and inspection. once we receive everything we will make a quote for the recommended services and/or replacement.

Hope that helps and give us an email for more info.

I have had a problem with securing the spreaders to the shrouds, resulting in the spreaders dropping. I am using stainless wire to seize them but still having a problem. Any tips on how to do this properly?

Seizing the wire onto spreaders with hinged spreaders is a bit of a trick of the trade that requires some practice. We use the X’s and O’s method. The end result should be something that looks like this… https://theriggingcompany.files.wordpress.com/2011/11/2012-06-07_14-26-09_899.jpg?w=900 . A trick to make the wire bite into the spreader end a bit more is to wedge a small piece of leather between the spreader and the wire before seizing. Also parceling and serving the wire where it intersects the spreader will help create more bite too. Lastly, and I don’t like this method but you can install a bull dog cable clamp beneath the spreader, nuts facing in, to keep it from dropping when slack.

I hope that helps a little. Thanks for commenting.

I am struggling to get enough rake into my mast. 33 foot Charger 33 keel stepped. Have loosened forestay and moved mast foot forward by about 10 mm. Should the chocks in the collar be adjusted? Runners and 2 spreaders, and check spreader. Spreaders do not have much aft angle. Move mast step more forward? Outers are tight with inners looser. Thoughts?

Hey Bernard,

Yeah, it sounds like chocks are the last thing. Maybe remove the chocks with the rigging slack and see if you can get the mast to sit where you like it with just hand tension. Then chock it where it wants to sit. It sounds like you are on the right track everywhere else, perhaps add a toggle into the headstay and shorten the backstay is next. Good luck and I hope that helps somewhat.

Hi, We have a Lagoon Catamaran with fractional rig, upper and lower shrouds, fore stay and upper and lower diamonds. No back stay. The mast has a degree of pre-bend. I do not plan to drop the mast.

I may have to do some work on the port side upper diamond. Is it as easy as just undoing the turnbuckle? Or do I need to loosen the starboard one at the same time. If it needs replacement should I also replace the starboard one even if in good condition?

As a further question, what happens if a diamond breaks, does it result in mast failure?

You would need to loosen the other counterpart to that stay for sure. It is just good practice, will keep the mast straight, and also make your life easier for removal install. Now, do you replace both? I don’t know. How old is the standing rigging? Why are you replacing the one? If it is not all due for replacement and you are just replacing due to damage, just do the one, but loosen both sides to do this.

Hope that helps and thanks for the visit.

Hello! I recently purchased a keel-stepped 1982 Goman Express 30 which came with an Alado Furler. I have been sailing it since May of this year. My question is this: Despite relocating mast wedges at the cabin roof to bias the lower mast aft about 2″, I still have a pronounced backward bend (10 degrees or so) just above the highest spreader. When sailing on jib alone, most wave action causes the mast to pump right at the bend point. I have a split backstay that is as un-tensioned as possible and the forestay only has another inch of adjustment left. There is no baby stay.

How can I get the bend out of the mast? How concerned should I be that the mast might break at that point?

Thanks in advance for your reply!

Eric Hassam – Delta Flyer

Thanks for taking the time to comment on our site. It sounds like you are on the right track. So one other adjustment that you have is the mast step position. This greatly affects mast bend on keel stepped masts. For a stronger bend and less rake, move the mast butt aft. For more rake and less bend (probably what you need to try), move the mast step forward a bit. If neither of these help, you may be off to have your headstay shortened and this means it is too long. This is likely not the case, but it is a possibility.

Keep in mind….A mast should have a slight aft rake bias along with a small amount of mast bend. This is quite normal. You can send us a picture if you’d like a second opinion on if it is over-bent. Having said all of that, even if you remove all of the mast bend, the mast may still pump. This is a design flaw in many spar designs that lots of end users have experienced. This can be remedied by redesigning the stay lay out. Is there a place for a staysail stay and/ or runner backstays? If so add them. Is there a place for a baby stay? If not, that may be a consideration.

Thanks again and I hope that helps.

Hi, I have a 48 foot yawl with a 7/8 fractional rig, is the tuning procedure the same as a masthead rig? I seem to have trouble getting aft rake and proper headstay tension. Also, is there a particular tension number the upper shrouds should have? many thanks in advance

Hi Bill, thanks for taking the time. 7/8 is very close and I would treat it like a masthead rig, especially if the none of the spreaders are aft swept. Tesnsion the headstay using the backstay(s). This should pull the top of the mast aft. If there are any other forward stays, i.e. stay sail stay, forward lowers, or anything else that could be holding the mast forward, go ahead and loosen those completely. You then may need to tighten the Tri-attic (the stay that connects the top of the mizzen and top of the main) if present. OR if the mizzen needs more rake too, then lossen all forward stays and pull it back using the available aft stays for this as well.

Hope this helps and please email us and send some pictures if you need more help.

I have a 1972 Morgan 27, which has both forward and after lower shrouds. I wish to remove the forward lowers so I can trim a 110% jib inside the stays. I see a lot of boats without forward lowers and think this will work OK, but wonder if I should increase the size of the aft lowers and beef up the chain plates. Any suggestions?

THANKS FOR YOUR INPUT. I AM GOING TO REMOVE THEM ANYWAY AND SEE WHAT HAPPENS. “HOLD MY BEER, WATCH THIS….” FAMOUS LAST WORDS.

Lol! Good luck. Call us if you need assistance.

I have rod rigging on my Beneteau 32s5

Any other guidance on tuning them vs wire rigging

Hi and thanks for commenting.

Just follow the guidelines in the write up. The over all goal is that the mast needs to be straight and in-column when looking at it from side to side.

Fore and aft, the mast should show a very slight lean aft. Depending on whether or not the spreaders are in-line or aft swept; you should also see some slight bend if there is any aft sweep to the spreaders just from the tension of the uppers.

A Rod stay tends to run a bit tighter than wire, so keep that in mind.

For racing, ideally once the static tune at the dock (the part we just talked about) is done, go out and sail tune. Do this by going hard on the wind and checking to see if the leeward shrouds are just starting to dance, this is ideal. If they are swaying about they are too loose for the current conditions. If the leeward shrouds are tight, they may be a touch to tight. Tension and loosen as needed; count what you did and to what shroud, then tack and do the same to the other side.

ALWAYS secure the turnbuckles when you are finished adjusting them.

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Wow, I would hate to be charged by her for three trips up the rig and forget the screw driver the rubber plugs that are sacraficial and replaced everytime removed just to clean the stainless 1×19 rigging.

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Standing rigging adjustments and tuning

• Thread starter MccNeo
• Start date Sep 15, 2016
• Macgregor Owner Forums
• Ask A Macgregor Owner

I have noticed several posts that result in various discussions about tension and adjustments of the standing rigging. The information available in the owners manual for the MacGregor 26S that I purchased used was of very little help. MacGregor was not very specific on the subject. If you push your boat hard, race your boat, or sail in winds subject to high velocities or gusts, then getting rig tension correct could prevent loss of the entire rig. Improper tensioning can result in hardware failures, excess stress to chainplates or deck fittings, and poor or sail trim. I have found various sail manufacturers will have rig tuning information on their web sites. These can be very helpful but not necessarily specific to the boat model. Also, since MacGregor didn't provide details, I looked to other boat manufacturers of boats similar in design and performance to the 26S for guidance. One item I believe to be essential to proper turning and adjustments is a Loos Gage. It typically comes with rudimentary instructions for use and basic tuning guidance. They run about $90. Rigging tension will change for a vessel that is adjusted on land and then launched (not be much but will be different). Also, it will change after about two or three weeks from initial tensioning. Rig tension should be checked every 6 to 10 months. I have provided one sail manufacturers suggestion for rig running below. Harry, please forgive me for not asking before posting: Tuning a Rig with Swept Aft Spreaders In my article on Controlling Headstay Sag I focused mainly on conventional rigs with in-line spreaders. On those rigs your adjustments are done mostly with the backstay, runners, and checkstays. Tuning a rig with swept aft spreaders and shrouds is quite different because in these rigs a large component of both headstay sag and mast bend are controlled through shroud tension. These rigs are most often found on boats with jibs that don't overlap the rig. To start you need to understand what the individual shrouds do, and what effect changing their tension will have. Your rig will have an upper shroud, also called the V1 or cap shroud, which runs from chainplate at the deck up to the hounds or point where the headstay attaches to the mast. It will have a lower shroud, called the D1, which goes from the chainplate to the base of the first spreader. If you have multiple spreaders you will also have diagonal shrouds that runs from the tip of the spreader below to the base of the spreader above. With a two spreader rig this would be called a D2, with a three spreader rig you will also have a D3 and so on. These diagonals may pass over the end of the lower spreader and continue to the deck where they are adjustable or you may have "discontinuous" rigging where each of the diagonals terminates at the end of a spreader where it will be adjustable. The V1 shrouds center the top of the mast in the boat but since they also pull aft they tighten the headstay and induce pre-bend in the mast from the compression load. The D1 shrouds support the sidewise load in the middle of the mast and since they are pulling aft on the middle they will also control how much pre-bend you have. If you have have a two or more spreader rig the upper diagonals, D2's, D3's, etc. will control the sidewise bend in each section where they are attached. Tuning one of these rigs takes some time because your ultimate goal is to reach a point where you have the correct amount of pre-bend, at the same time that the mast stays straight sideways, at the same time you have the correct amount of headstay sag. Start by setting the mast with the desired amount mast rake. This is set only by the length of the headstay; make it longer and you have more rake, shorten it and you will have less. The boat designer, if available, will have an amount he designed for the rig when he developed the rig and hull package. If you are sailing in a one-design class there will probably be tuning guides developed by the top sailors in the class that will give you a rake measurement. In the absence of either one of those try starting out with about 1 degree of rake. That is an amount that is often used by designers and should certainly be close enough for a good starting point. 1 degree equates to about 4" of rake for every 20 feet of mast. Next you will need to know how much pre-bend you should have in the rig. The spar makers should be able to give you a measurement for the amount of pre-bend they designed the mast to have, or again if you are sailing in a good one-design class there will be tuning guides with the amount of pre-bend that has been proven to work in the class. With this information at hand start with a basic "dock tune". With all the diagonal shrouds slightly loose start tightening the V1's, measuring as you go to keep the top of the mast centered in the boat. Tighten them to the point that you have about 25% more pre-bend in the mast than your designed spec. Next tighten the D1's enough to pull the pre-bend back to the desired amount while sighting up the mast to see that it is straight side to side. If you have other diagonals go ahead and tighten them just enough to take the slack out, again sighting the mast as you go to keep it straight side to side. The final tune has to be done while sailing. You should do the initial tuning in light to medium air with just the main up and then as you dial that in work up to more wind. Start by sailing hard on the wind and sighting up the mast, it helps to make notes as you go. First look at the leeward V1, if it is very loose you will need to tighten both V1's equally to keep the top of the mast centered. Take up turns on the leeward V1 enough to take about 1/2 of the slack out of it. Now tack over and tighten the other V1 the same amount. Now look at your pre-bend, since you have tightened the V1's the mast will have a little more pre-bend so tighten the D1's enough to pull the bend back to the desired amount. do this by tightening up the leeward D1 a turn or two at a time, tacking over and adjusting the D1 on the other side. You have to keep sighting up the mast on each tack to be sure your are keeping the middle of the mast centered. Once the D1's are set move up to any other diagonals you have, adjusting the leeward side a turn at a time, tacking over and adjusting the other side as you go. If you have discontinuous rigging this has to be done by a crew member that is aloft so he can adjust the turnbuckles that are at the ends of each spreader. Once your are satisfied that the mast has about the right amount of pre-bend and that it is staying straight side to side, you can start on you final tuning that involves fitting the rig to you sails. Your mainsail should have been built to match the amount of pre-bend the rig builder specified but you can change the amount of pre-bend slightly to make it fit better if needed. Do not reduce the amount of pre-bend to less than the specified amount! Next hoist the jib and sail up wind with it, tacking back and forth a few times while checking the mast to see that it is still straight. At the same time look at the headstay sag and how full the jib is. If you have too much headstay sag when you have enough backstay tension on to make the main look good you will need to tighten up the rig. Tighten up the leeward V1 by two or three turns and tighten up the leeward D1 by half that amount. tack over and do the same on the other side while looking the mast to see if the ratio you used between the V1's and D1's was about right to keep the mast straight side to side. You may have to adjust the D1's a little more or a little less and then re-adjust any other upper diagonals you have. This is a slow process and needs to be done in different wind conditions to really get it right. You will find that to really do it right you will need to adjust the shroud tensions differently for different wind conditions. This need to be done by tuning in the different conditions while sailing with the jib you will use in those conditions. Each jib is cut for different amounts of headstay sag so the overall rig tension has to be changed to match that sag. On boats with multiple jibs you shouldn't have to adjust the rig very much because the jibs should have been designed to work in a narrower range and cut to match the headstay sag you get. On boats that sail with only one or two jibs you will need to adjust the rig a lot more to make the jib work over a wider range. Make sure you record the exact settings you start with and how much you change it for different conditions. This is often done by having a "base" setting and then keeping track of how many turns on or off you put on each turnbuckle as conditions change. This works but it is very easy to lose count of exactly what you have done. A much better way is to get a dial caliper that costs around $25.00 and measure the distance between the studs inside the turnbuckle. Record these numbers in your rig notebook for the different settings. That way you always have a number you can come back to no matter what happens, if you get confused about how many turn you went in which direction, or even if you pull the rig out. Getting back to your desired setting is just a matter of tightening each turnbuckle to the desired measurement. This whole process is slow and usually an ongoing process. Each time you race you should record the conditions, the rig settings, and your results. If the results weren't what they should have been make small changes in the rig to match the mast bend and headstay sag to what you needed to do better. Write it down each time and you will develop your own set of settings that work for you boat and your sails. Harry Pattison President Elliott/Pattison Sailmakers  

Great information Thanks for sharing  

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J/105 TUNING GUIDE

Download the North Sails J/105 Tuning Chart

Part 1: Rigging Preparation

The following recommendations are small changes that should be made to the stock J/105 to allow you to get the most from your North Sails and make the boat easier to sail and set up.

Head swivel shackle

The North Sails jibs come with a webbing loop at the head. It is critical to have a 90-degree “twist” shackle to attach the sail to the swivel. A standard shackle will cause a hard spot at the top of the jib as the sail is torqued.

Remove backstay toggle

Many J/105s come with a toggle that rotates the hydraulic cylinder 90-degrees so that the handle faces forward. While it is nice to have the handle forward, this toggle reduces the throw of the backstay adjuster too much so that you are not able to get enough tension in heavy air. Some of the older boats actually need to have the backstay rod shortened to get enough backstay throw.

Change to 4:1 or 6:1 Cunningham

The standard Cunningham is 2:1 and led aft to a cabin house halyard stopper. This system should be replaced with the lower purchase with integral cleating shackled to the ring on the top of the Quik Vang. This allows for easier and more precise Cunningham control by a forward crewmember. Many boats then rig the asymmetrical tack line through the free stopper.

Mark the tack line at the cleat

Put marks on the tack line at the proper range of settings. As you approach the windward mark you can then pre-set the tack line so that when you extend the pole and set the spinnaker the tack will be set properly. The tack line is much easier to work with in this placement than on the side of the cabin house.

Move mainsheet swivel base forward of the traveler

This allows for easier trim of the gross tune by the main trimmer, especially when tacking.

Tapered Spectra spinnaker sheets

These sheets have a light uncovered portion that attaches to the sail, with a covered portion that goes on the winch. The sheets should be 3/8” Spectra cored line with the cover removed at the sail end of the sheet. These lightweight sheets are used in all conditions and help downwind performance in light air. Heavy sheets pull down on the leech of the spinnaker in light air, closing the leech too much.

Bypass the jib sheet turning block

The standard set-up for the jib sheet is to run the sheet from the clew of the jib, through the lead block, through the turning block near the rail, and then to the winch. This set-up makes the lead block lean over to leeward, increasing sheeting angle. In light and moderate air, the jib will sheet tighter to the centerline if you lead the sheet straight to the winch from the jib lead block. In heavy air, it can be faster to use the turning block to sheet the jib outboard slightly.

Part 2: Rig Set-Up and Preparation

Tools and items required: Loos RT 10M Rod Tension Gauge, 2 crescent wrenches, spray lubricant, bosun’s chair and 50’ metric tape measure.

Part of the success of growth of the J/105 Class is the tight class rules and limited sail inventory. With the J/105s limited sail inventory of only one headsail, aggressive rig tuning is essential for performance throughout the full range of wind conditions. By definition, the North Sails “AP” inventory is optimized for 9 to 12 knots. This is actually the easiest condition to sail in, so the racing tends to be at its tightest. Having really fast sails in this condition is key to gain a slight speed edge and the AP inventory is designed to give you just that. The heavy air “HA” inventory is optimized for 13-20 knots. In the extreme conditions of light and heavy air the rig must be manipulated to enhance the sail shapes for those conditions. The result of proper rig tuning is the correct relationship between mast bend and headstay tension to get fast shapes. The North inventory has been designed to make these transitions easily with the correct tuning to be fast in all conditions.

Step One: Check Mast Butt Position

The measurement from the front of the forward bulkhead to the aft face of the mast should be 24.46cm (9 5/8”). This is very close to the center of the step. For the HA sails, the mast butt should be 26.00cm (10 1/4”) from the bulkhead.

Step Two: Check J Measurement

The J measurement is the distance from the headstay intersection to the deck to the forward face of the mast. This should be a minimum of 4.11m (13’6”). Use mast chocks or SparTite to achieve this position.lean over to leeward, increasing sheeting angle. In light and moderate air, the jib will sheet tighter to the centerline if you lead the sheet straight to the winch from the jib lead block. In heavy air, it can be faster to use the turning block to sheet the jib outboard slightly.

Step Three: Set Mast Rake

Rake is controlled by headstay length. The headstay should be set at the class legal maximum rake, 13.035m (42’ 9.125”). Hoist a crewmember up the mast and have them hold the butt of the tape measure at the center of the pin that secures the forestay to the mast. Measure to the to of the furler drum (measurement A), then measure from the top of the furler drum to the bottom of the furler drum (measurement B), then from the underside of the furler drum to the intersection of the stem and sheer line of the boat (measurement C). The overall headstay measurement is then the sum of A+B+C.

Step Four: Centering the Spar

Put a mark on the rail of the boat on one side even with the chainplates. Measure this distance from the headstay attachment on the bow. Put a corresponding mark on the other side, the same distance from the headstay. At this point the Upper Shrouds (Caps) should be hand tight and the Intermediates (D2s) and the Lowers (D1s) should be loose. Hoist the tape measure to the top on the centerline jib halyard. Measure to the marks on either side and adjust the Caps until they are equal.

Step Five: Tensioning the Shrouds

Tighten the D2s and D1s to hand tight. Add 8 full turns to the Caps. Then tighten the D2s 6 turns. This should be done incrementally (2-3 turns at a time per side) sighting the mast to be sure that the mast is in column. Add turns to one side and remove turns from the other to bring the mast in column. This added tension that you have applied has probably made the D1s slack, so double check to make sure that they are hand tight.

Step Six: Check Shroud Tensions with Loos Gauge

Put marks on the shrouds 2m (6’ 6 3/4”) up from the deck. Put the top post of the gauge on this mark when measuring tension. Be sure to have the backstay released when measuring tension with the Loos Gauge. For the base setting for 10-14 knots TWS the shrouds should read the following:

All Purpose Sails  Caps: 35 D2s: 10 D1s: 0 (10 cm play)

Heavy Air Sails Caps: 55 D2s: 25 D1s:10 (hand tight)

You should double check to be sure that the mast is still in column at the dock when the rig is at full tension. At the base setting, the mast should sit with virtually no pre-bend up to the hounds.

You are now at the “base” setting and ready to go racing. From here follow the Quick Tuning Guide to optimize your J/105’s performance for various wind conditions.

Advanced Tuning – Beyond the Numbers

The North Sails J/105 Tuning Guide is very refined, and has been used to the letter to win many events. However, understanding the fundamental concepts of how tuning affects the rig and sails is important to be able to check that the settings are right for your boat, as well as customizing your own tuning numbers for your sailing style. Keeping good records is the key. Keep a Wet Notes pad on your boat and record your rig settings, wind speed, sea state, and your speed and pointing relative to other boats. This will help you to see what is working best for you and fine tune your own numbers.

Changes to shroud tension affect the rig in two ways: 1) headstay tension & 2) mast bend. Tighter Cap shrouds generate more headstay tension by pulling back against the headstay. A good guide for Cap (upper) shroud tension is that the leeward Cap shroud should just go slack in all but the heaviest of wind conditions. Tighter D1 (lower) and D2 (intermediate) shrouds generate more headstay tension by reducing mast bend and compression. The important factor of the D1 anD2 adjustment is the relationship to the amount of backstay used in each wind condition, which affects mainsail shape. Tight D1s and D2s will make the mast too straight (main too full and draft forward) when no backstay is used, and conversely loose D1s and D2s will allow the mast to bend too much (main too flat or even inverted) when a lot of backstay is used. The final D1 and D2 rig tension will be dictated by mainsail shape.

The light air performance of the J/105 can be dramatically improved with leeward mast sag in under 12 knots. This is side-to-side sag from the partners to the hounds. This can only be seen under sail and will not happen at the dock. The settings from the Quick Tuning Guide should generate this sag, but all masts are a little different, so you may need to adjust your intermediates and lowers to achieve it. Loosen the intermediates and lowers so that there is 2.5cm (1”) of leeward sag halfway to the hounds in under 9 knots and Zero in 9-12 knots. In general the intermediates will need to be eased twice as many turns as the lowers to achieve even sag.

Part 3: Mainsail Trim

The J/105 relies on much of it’s power from the mainsail with the class inventory. The mainsail is very easily adjusted because there are many shape controls including mainsheet, traveler, backstay, cunningham, vang and outhaul. Proper mainsail trim is achieved by balancing the speed and pointing with its twist, angle of attack and overall power. Proper communication with the helmsman for the feel of the boat and performance vs. the boats around you are the key to establishing the correct balance of those three elements.

Mainsail Angle of Attack — The Traveler

The traveler controls the boom angle to the centerline of the boat, which is described as angle of attack to the wind. Much like the sheet, a narrow angle of attack (traveler high) is used for pointing and powering up the boat and a wide angle of attack (low traveler) is used for acceleration and depowering the boat. Carry the traveler as high as possible without making the boat heel too much.

In light to moderate conditions the boom should be on centerline or slightly above. In very light air, when the main is twisted, setting the boom actually above centerline will put the lower third of the main parallel to the centerline of the boat. A good gauge for this is to look where the bottom batten is pointing. The bottom batten should point at the backstay in very light air. If it is pointing to windward of the backstay, the traveler is too high.

As the breeze builds, the traveler should be played aggressively to control heel and keep the boat on its feet. If the boat heels too much, the boat will get too much helm and the helmsman will have to use much rudder angle to keep the boat going straight. The optimum rudder angle to create the most lift is around 4 degrees. There are times when more angle than that is unavoidable, but 5 degrees of rudder angle should be the most that you try to use. Rudder angle can be monitored by putting a tape mark on the top of the wheel when it is perfectly straight. The main trimmer can notice when the helmsman is using too much helm (or not enough) and adjust the traveler appropriately.

Mainsheet vs. Traveler for Various Sea States

One of the more difficult things to determine is how to depower the main in moderate to heavy conditions. As we have learned, you can depower the main by either twisting the main by easing the sheet or letting the traveler down. The technique used should be determined by sea state, which will affect how the helmsman has to steer the boat. In flat water, the helmsman should be able to use very subtle steering changes. Hours of on-the-water testing has shown us that depowering by lowering the traveler and keeping a tight, untwisted leech produces the best VMG. You can point reasonably high in flat water without slowing down and the tight leech will help with pointing. We have found that twisting the main in flat water in moderate air only makes you lose height. With this style the traveler is played to maintain the proper angle of heel. However in waves and chop, the opposite has proven to be faster. In waves and chop the helmsman has to be more aggressive with the helm. With the wider range of steering keeping the traveler higher (with the car near centerline) with a more twisted main allows the helmsman to steer through wider angles and accelerate as needed in the waves. With this style the mainsheet fine tune is played to maintain the correct trim and angle of heel as the helmsman steers through the waves.

Overall Power – The Backstay

The backstay is the most important sail control for setting the overall power of the sail plan. The backstay is the universal control to modify the shape of the main primarily, but also the jib. The North Class Inventory has been carefully designed so that backstay adjustment changes the shape of the main and jib in unison. As backstay is applied the mast bends, flattening the main. It also pulls aft against the headstay, reducing headstay sag, which flattens the jib. By flattening the sails the boat’s power is reduced as the boat becomes overpowered and heels too much. Flatter sails can be trimmed harder than full sails so when it is windy it is better to set the sails up flatter and sail with less twist. This will allow you to point higher.

As stated in the tuning section of this guide, having the rig set up properly for the wind conditions will allow you to get the most benefit of adjusting the main and jib together with the backstay, but it is also the control that allows you to set up the sails as best you can when the wind changes and you are no longer tuned correctly.

With a loose rig the main will flatten out faster than the jib. This is because the loose D1s and D2s will allow the mast to bend, which will flatten the main. However, since the mast is bending, the main will get to a point where it over bends before you can bottom out the backstay. By not being able to bottom out the backstay, the jib will still be a bit fuller than is ideal at this point since 1) you can’t pull on the full range of backstay and 2) the mast will compress more so the backstay tension will not transfer as well to the headstay.

Conversely, with a tight rig, the main will stay fuller when the backstay is eased, while the overall rig tension will keep the headstay tighter and thus keep the jib a bit flatter. It is important to understand this relationship between how the backstay and rig tuning affects sail shape when you may not be tuned correctly. If your rig is too loose, use more backstay to set the main up flatter, knowing that your jib will be fuller than ideal. If your rig is too tight, use less backstay to set the main up fuller, knowing that your jib will be flatter than ideal. In general, it is better to be set up with a flat main and a full jib so it is better to err on the loose side of the rig tuning matrix if you expect the wind to change. It’s much easier to depower the J/105 than it is to power it up so always tune for the lulls!

As the mast bends it has an immediate effect on the luff and leech tension, so other controls must be adjusted in conjunction with the backstay. When you pull the backstay on, the mainsail will twist more so more sheet will have to pulled on to reset the twist. More backstay will also loosen the luff, so more cunningham will be needed. Don’t forget to ease the sheet and the cunningham after you ease the backstay.

Other Mainsail Controls

Cunningham he cunningham controls the luff tension of the mainsail. Luff tension controls the draft position of the mainsail. As backstay tension is applied, the mast compresses and the main appears to fall down a little and the draft will move aft. Pull on the cunningham to move the draft forward to the desired position. As well as moving the draft, luff tension will also make the main somewhat flatter. In light air, you should see slight wrinkles coming from the sail slides. In moderate air the luff should be smooth. In heavy air, the luff should be tensioned past being smooth to set the draft position and flatten the sail.

Vang With the non-overlapping jib, in order for the mainsail to generate enough power in light air, a certain amount of depth has been designed into the lower portion. In over 12 knots begin to pull on the vang to induce low mast bend to flatten the lower third of the main. When it is really windy pull on the vang quite hard to help bend the mast. be sure to ease the vang at the weather mark! Before you ease the main, ease the vang to allow the main to twist as you bear off. If the vang stays on too hard, you may not be able to bear away, or worse you could break the boom.

Outhaul The outhaul also controls the sail shape in the lower third of the mainsail. Easing the outhall makes the lower third of the mainsail fuller and tightening flattens the lower third. In light air the outhaul should be slightly eased and pull it progressively harder as the wind increases, to the point where you should pull it as hard as you can in over 15 knots.

Part 4: Jib Trim

The J/105 Class Jib has a very tough job. It has to be fast in all wind conditions, where other 35’ offshore one-designs allow three headsails! The single jib inventory presents a tough challenge for sail designers to create a sail that is versatile enough to cover the entire wind range, while being constructed so that it can be light enough to perform well in light air, yet being strong enough to handle heavy air. The 3DL jib is the ultimate solution to handle this daunting task. The latest design has been refined to be responsive to the few controls that can change the shape. The 3DL process is the only way to create a sail that is minimum weight, yet is strong enough for heavy air.

While the North 3DL jib is refined to a level that makes it very easy to enhance the light shape in light air and a heavy shape in heavy air, it is important for the trimmer to be able to manipulate the sail appropriately. The primary controls that we have to affect the sail shape are the halyard, sheet, jib lead placement and headstay tension.

Jib Halyard

The halyard is the most important sail control for shaping the jib and it has a much greater affect on sail shape than the cunningham on the main. However, just like the cunningham on the mainsail, the halyard controls the entry angle, draft position, and overall depth in the sail. A tighter halyard will produce a more draft forward, rounded entry shape, with less overall depth. A loose halyard will produce a more draft aft, finer entry shape with more overall depth. As a general rule, the halyard should be tensioned to just barely remove the wrinkles in the luff. In lighter air wrinkles can just be visible, in moderate air the luff should be smooth, and in heavy air the halyard should be pulled 2.54-7.62cm (1-3”) past removing the wrinkles.

In flat water, a looser halyard can improve pointing with a finer entry angle. In waves and chop, a tighter halyard will produce a more rounded entry and more open leech, which will have a wider steering groove and be better for acceleration. If you try the loose halyard and your helmsman seems to be struggling to find the groove, try a slightly tighter halyard.

As sails age, the entry tends to get finer and the draft starts to move aft. An older sail will require more halyard tension to achieve the same shape as a brand new sail with a looser halyard.

The sheet is the most important control for adjusting the jib once the draft is set. The general rule is to trim the jib as hard as possible without slowing the boat down too much. The jib needs to be played in conjunction with the main and the helmsman’s steering. The sheet tension will change with each change in the wind speed. When a puff hits, the leech will become more open. Be careful not to trim the jib too soon. Allow the leech to stay open to take advantage of the puff to accelerate the boat and them trim in once you have accelerated to increase pointing.

The Class mainsails are fitted with a spreader window so that you can see the jib leech on the lower spreader. Put tape marks on the spreader at 7.62cm (3”), 15.24cm (6”) and 22.860cm (9”) in from the spreader tip. In general you should trim the jib so that it is at the spreader tip in very light air, 7.62cm (3”) inside the tip in light air, 15.24cm (6”) to 22.860cm (9”) inside the tip in moderate air, then back out to 7.62cm (3”) in heavy air. These guidelines are subject to change based on sea state. The jib can be sheeted harder in flat water than in waves and chop. Be careful to only make small sheet adjustments. Due to the high aspect nature of the jib, small changes make a big difference.

The jib lead should be used to control the top and bottom shape of the jib. The middle of the jib is not as affected by lead position as much as it is with sheet. Once the sail is trimmed to the appropriate spot on the lower spreader, adjust the lead to make the top and bottom look right. Moving the lead forward will make the upper leech more closed and the foot rounder. Moving the lead aft will make the upper leech more open and the foot flatter.

The median jib lead position is slightly aft of the middle of the jib track, which is about 9” aft of the chainplate. This position is also just forward of the window on the side of the cabin house.

Headstay Tension

Headstay tension has the most dramatic affect on the overall camber of the jib. Headstay tension affects headstay sag. This is a difficult thing to visualize, but it works much the same as mast bend affects mainsail shape. As the headstay sags, it pushes the luff towards the leech, which increases camber. Conversely as the headstay gets tight, it pulls the luff away from the leech, decreasing camber.

Clearly this is very important, but has been listed last here because it is very dependent upon rig tuning. Headstay tension is achieved by a combination of a tighter rig and a tight backstay. As we have learned in the rig tuning and main trim sections, rig tuning and backstay tension has a great affect on mainsail camber as well. The Class main and jib designs and the tuning guide shroud tensions have been carefully developed to have the backstay control main and jib camber in unison. If you are tuned properly, when the main sets up correctly, the headstay tension will be correct as well. Your headstay tension should be almost self-tending.

During a race, the only way to adjust your headstay tension is with the backstay. Because of this it is important to know how you are tuned and whether you are actually sailing in the right wind speed for your tuning. The backstay will be the key to get the most of the set up that you have when you are not tuned perfectly. Simply, if there is less wind than you are tuned for, use less backstay tension to power up the sails as best you can. If there is more wind than you are tuned for, use more backstay tension.

A good technique is to tape a batten with marks every 2.54cm (1”) on it to the backstay cylinder. This will help you to be able to record your settings and duplicate them later.

Part 5: Crew Weight Placement

With the new “float line” rule, this discussion has become much easier now that we know that all boats should float the same. The goals of weight placement are to 1) control helm and 2) reduce wetted surface in light air.

In light air the crew should be well forward and to leeward both upwind and down. Two crewmembers should be forward of the shrouds to leeward. Remaining crew should be up near the shrouds. There should only be one person in the cockpit other than the helmsman. In really light air the main is not trimmed that often and the helmsman can make small adjustments. Being to leeward helps heel the boat increasing helm giving a better feel and allows for the best pointing and rudder lift. Being forward allows the bow to dig in which also helps pointing as well as reduces wetted surface by getting the transom out of the water.

Moderate Air

In moderate air the crew can begin to slide back as they begin to move to weather. Once anyone goes to weather they should be stacked just behind the shrouds. At this point if you have a dedicated main trimmer, he can slide back to his station upwind. Downwind as soon as there is constant adequate pressure on the sheet and you begin to try to sail low the crew should move to weather to help rotate the spinnaker to windward out from behind the main. This happens at about 10 knots. There is plenty more coming on downwind sailing in Part 6, starting on page 21.

In heavy air the crew should continue to move aft, especially in waves. If you notice that your helmsman has to steer a lot to keep the boat going straight (dialing for dollars), move aft and as the bow lifts the boat will track straighter. Since crew weight is limited the guys who are on the rail need to hike hard. Remember, sailing is a sport and it’s a boat not a couch!

Part 6: Downwind Sailing

Sailing the J/105 downwind can be one of the more difficult things to do well. Paying small attention to the minor details can make a huge difference. The key to fast sailing downwind is good communication between the trimmer and the helmsman. The trimmer should constantly be telling the helmsman how much pressure he has in the sheet. This will allow the helmsman to know if he can bear off a little more, but more importantly when he needs to head up a little bit to build pressure.

The J/105 has an asymmetric spinnaker set on a centerline sprit. The goal in downwind sailing is to maximize downwind VMG. This is achieved by sailing a wind angle tight enough to keep speed, but sailing lower towards the mark whenever possible. The North Sails asymmetric has been designed as a running spinnaker for optimum downwind performance at the apparent wind angles that produce the best VMG for the J/105. The sail has been designed to rotate out to windward to project the maximum sail area out from behind the mainsail. Always hoist the sail all the way to the top. Due to the luff length restriction in the rules, the tack of the sail is never set all the way down to the pole. Raising the tack helps the sail to rotate to windward.

Light Air Sailing (0-9 knots TWS)

In light air, you must sail tighter angles for best VMG. The tack is set 0.3m-0.6m (1-2’) off the sprit. The crew should be forward and to leeward. Keep the crew weight as low as possible. Steer down in the puffs until the pressure sheet starts to get light and then head up slightly. Communication between the trimmer and the helmsman is key. Try to find the lowest angle you can sail before the speed drops. Don’t forget about the main! Proper mainsail trim is essential to good speed. The vang should be set so that the top batten is open by 5 degrees. A good trick to help acceleration out of the jibes is for the main trimmer to hold the sail in a bit after coming out of the jibe. When the asymmetric is jibed, it needs to

be overtrimmed to make it “pop” through. When the spinnaker is overtrimmed, it blows air back into the mainsail relieving pressure from it. By keeping the main in, it will keep the main pressurized as well as opening the slot between it and the spinnaker to get the air flowing over it faster. The main trimmer can easily feel if the main is pressurized by the pull on the sheet. Ease the main out slowly as the pressure on the sheet builds as the spinnaker is eased.

Moderate Air Sailing (9-12 knots TWS)

In moderate air, there is a wide range where you can sail. Lower is best as long as you can maintain your speed. The tack line is eased 0.6-0.9 (2-3’) off the sprit. The same principles apply to steering as in light air. Once the boat feels well pressured, the crew should move to the windward side to help rotate the spinnaker. In this range the crew should be very active moving to weather when you head down in the puffs and back to leeward when you head up in the lulls.

Heavy Air Sailing (12+ knots TWS)

In over 12 knots, the boat is well pressured up going downwind. At this point you want to sail as low as possible most of the time. There will almost always be good pressure on the sheet but when you sail too low, the sail will become blanketed behind the main and collapse. The sheet is well eased to get as much of the sail out from behind the main as possible. The crew should be to windward at all times. Heel the boat to windward by as much as 10 degrees. The vang should be set so the top batten is parallel to the boom.

DOWNWIND NOTES Good coordination between the trimmer and helmsman will result in very subtle changes in the sheet. A properly coordinated team will only adjust the sheet by a couple of feet. If you find yourself constantly trimming and easing more than 3 feet of sheet than your coordination should be improved. Be careful not to try to sail too low and collapse the spinnaker. A collapse will result in around a three-boat length loss!

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