Chapter 1
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Forward
Introduction
How to Buy a Sail
Rig Dimensions
Chapter 2
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Sail Cloth
Sail Cloth Fiber Comparison
Chapter 3
Sail Construction Methods
Chapter 4
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Mainsails
Genoas and Other Jibs
Spinnakers
Asymetrical Spinnakers
Cruising Spinnaker (The UK Flasher)
Dousing Sock (The UK Stasher)
Staysails
Drifter
Blast Reacher
Storm Sails
Chapter 5
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Main Sail Trim
Genoa Trim
Sailing to Telltails
Chapter 6
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Spinnaker Trim
Spinnaker Jibes
Spinnaker Douses
Chapter 7
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Cruising Spinnaker Handling
Cruising Spinnaker Trim
Cruising Spinnaker Jibes
Chapter 8
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Tuning Your Rig
Chapter 9
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Sail Care
Applying Spreader Patches
Chapter 10
Glossary
Forward
Established in 1946, UK Sailmakers is one of the oldest lofts in North America. Over 50 years
later, the UK group has 25 lofts and service centers around the world. UK has been on the leading
edge of sail development ever since the late ’40s when Ulmer Sails dominated the Star class and
other one-designs like 5.5 Meters, Snipes, Lightnings and Comets
In the early ’70s, UK became known as the only place to buy spinnakers, since we were the first
loft to perfect the radial-head construction tech-nique. Not being able to produce spinnakers fast
enough, UK branched out with independently-owned franchises. The computer programs we
developed for sail design and construction ensured that sailors across the country could buy the
same fast sails from any UK loft.
In the early 1990s, UK Sailmakers hired Jack Kleene, UK's Technical Director, to write and
constantly update the most sophisticated computer design program in the industry. Jack headed the
flow code sail shape research project for America 3 when she successfully defended the America’s
Cup in 1992, and he continued to work with A 3 on their successive campaigns. His knowledge of
sail shapes and computer programing is vast.
Owen Torrey, our designer emeritus, affectionately called “The Prof,” created all our early
computer programs. Owen invented the Flasher — an asymmetrical pole-less cruising spinnaker
that permits short-handed sailors to enjoy the benefits of a spinnaker while flying a sail that handles
as easily as a genoa.
Over the past decade, UK continues to develop our leading-edge load-path technology TapeDrive® sail construction system. Tape-Drive is a patented construction method that enables UK to
build sails that last longer, hold their shape better and weigh less. Tape-Drive® is a reinforcing
system of high-strength, low-stretch tapes that are glued to a sail. The tapes are laid along the
computer predicted load paths that run between the corners of the sail. With the tapes carrying the
major loads, sailcloth and shaping seams don’t distort. Tape-Drive® gives the strength of a two-ply
sail at a fraction of the weight.
In the mid 1990s, the UK Sailmakers group continued to grow and expanded into Europe, doubling
the size of the group. For the nearest UK Sailmakers loft, see our lofts list.
Introduction
UK Sailmakers is happy to make this booklet on sailmaking available to our customers. The first
half should be used as a reference tool or as a way to gain enough information about sails that you
can work with your sailmaker to ensure that you get the sails that best suit your needs. The second
half of the book gives hints and tips on sail trim, sail handling, rig tuning and sail maintenance.
Sailing, like everything else, has its own jargon. For those on the inside, the nomenclature can
facilitate communication. But for the uninitiated, it has just the opposite effect — the specialized
vocabulary creates a fog. One of the important purposes of this booklet is to clear away that fog by
giving meaning to the jargon as clearly as we can. If the booklet does its job, when we talk about
things like “J” and “Tape-Drive® ,” you won’t have to wonder what we’re saying. As an example,
we have found that some of the terms on a price list are unfamiliar to many of our customers.
Some sails go by different names at different lofts. Also we find that some people don’t know
the purpose or use of some of our more specialized sails. For these reasons, we’ve prepared this
explanation of the terms used on our price list. There are some things you should understand about
sailmakers’ price lists in general, and about ours in particular. There are literally hundreds of
different types, classes and sizes of boats for which sailmakers must provide price quotes. For each
boat, many different sizes and types of sails can be supplied in a variety of fabrics and weights.
Obviously, the task of preparing and keeping all these price lists current would be impossible
without some standardized approach. These lists are designed to price sails for an average sailor’s
use. If the sail that you are interested in is not shown, or is shown in a different size or fabric
weight than what you want, don’t think that we don’t make it. Every sail we make is custom made,
enabling UK to make sails to meet your specific requirements. We’ll work with you to design and
produce the optimum sails for your boat based on how you use your boat and your budget. To
begin with, we’ll talk about how to buy a sail, sailcloth, different construction processes, followed
by the different sails we make and their purposes.
By: Adam Loory and Owen C. Torrey, Jr.
How To Buy A Sail
Buying a new sail should be a pleasure, not a terrifying, difficult or mysterious experience. If
you're a bit concerned about this, we'd like to explain the process.
Sails are made to fit your boat, for the kind of sailing you want to do, and the winds and waters
you sail in. The more information we have about you and your boat, the more accurate our quote
can be and the more tailored-for-you we can make your new sails.
Our staff is very experienced and can usually make suggestions to help you, starting with these
eight questions:
1. What kind of boat do you have? We need the make and model. If you say a 40-foot
Beneteau, we can't tell whether that's an Oceanis 400, a 40CC or a 40.7 — all different. So,
be explicit.
2. In what year was your boat built? Builders often make changes year by year.
3. What rig does this have? Many builders offer standard and tall rigs. For example, the
Catalina 30 comes either way and there is a very large difference between the two masts.
4. Has the rig been modified? Owners occasionally lengthen their boom or add a short
bowsprit to increase sail area on under-canvassed boats. Has a furler been added?
5. Where do you sail? Sails cut for long ocean swells should have a different shape from those
used in choppy waters. Some places have strong winds, others zephyrs.
6. Do you race, cruise or do both? The choice of materials and features you should have will
vary to suit your usage.
7. What's the reason for buying a new sail? Are you replacing an old one, moving to different
waters , heading off on a worldwide voyage, looking for more speed and/or durability?
8. What key factors will influence your purchase? Can you rank factors such as price,
performance, multi-purpose use, and durability
To generate a quotation, we'll need answers to those eight questions, especially the ones which
have to do with dimensions and tell us how you plan to use your sails. Our computerized database
has rig measurements for thousands of boats, so the chances are high that we'll have yours in our
system. We do have one reservation in this quotation: it is subject to verification that we've
actually identified your boat correctly - insuring that the final measurements turn out to be
reasonably close to what were used in making our quotation.
If our price quotation is acceptable to you, we'll send you a confirmation form to sign. It
includes all sales terms. A deposit of 50% will get your sail started in production; the balance is
due when your sail is delivered. Normally, this takes only 2-4 weeks, but orders placed when lofts
are busiest (early spring, especially) will take longer.
Before we actually start building, we'll need some very specific measurements. If your boat is
near one of our lofts, we'll come over and measure; if not, we'll mail you a measurement form.
When you see this form, you will quickly appreciate how "customized" every one of our sails is.
The following rig dimensions designated by "I", "J" "P", and "E"
are needed to produce a price quote. They are convenient names to use
because they are short and are understood throughout sailmaking..
 "P" is the luff length of the main-sail, measured along the aft
face of the mast from the top of the boom to the highest point
that the mainsail can be hoisted.
 "E" is the foot length of the main-sail, measured along the
boom from the after face of the mast to the outermost point on
the boom to which the main can be pulled.
 "I" is measured along the front of mast from the highest
halyard to the main deck. The main deck is where the deck
would be if there were no deckhouse.
 "J" is the base of the foretriangle measured along the deck
from the headstay to the mast.
 "JC" is the greater of the following three dimensions: "J", the
length of the spinnaker pole, or the maxi-mum width of the
spinnaker divided by 1.8. Under most measurement rules, "JC"
is used, along with "I", to determine the size of a spinnaker.
 "PY" and "EY" are, respectively the luff length and foot length
of the mizzen of a yawl or ketch mea-sured in the same manner
as for the mainsail.
 "IY" is the "I" measurement for the staysail halyard.
 "JY" is the base of the staysail foretriangle measured along the
deck from the staysail stay to the mast.
Finally, here are two helpful comments. First, measuring your old sails is of little use: think of
that approach as asking a tailor to make you a new suit just from looking at an old suit. And a
picture is, as they say, worth a thousand words: snapshots of your gooseneck, genoa track location,
headsail tack fitting, furling gear, etc. can be of great value to us; these don't need to be fancy, just
clear.
There's always the phone. Don't be reluctant to ask questions. We welcome hearing from you
and making this process as fun, easy and exciting as it should be.
Sailcloth Information
The last few years have seen a virtual explosion in the development of new woven and
laminated sailcloths. Until the 1980s, woven polyester (better know as Dacron — Dupont's
tradename for their polyester yarn) was the only sailcloth in use. Today's cloths include not only
the familiar woven dacrons and woven nylons in various weights and finishes, but laminates using
Kevlar, Technora, PBO Zylon, Pentex and Spectra yarns.
Woven Polyester or Dacron®
Woven polyester sailcloth is extremely durable and relatively inexpensive. Sailmakers know its
performance characteristics well since they have been using it since the mid 1950s. When
durability is the primary concern, Dacron is the cloth of choice.
Specific styles of woven polyester are commonly named by weight, such as "6.1 oz. Dacron" or
"8.3 oz. Dacron". It should be understood that these designations are names and not necessarily
actual weights. There is a considerable variation, both up and down, between the actual weight and
the named weight assigned to a particular fabric by the manufacturer. This variation is inherent in
the manufacturing process, and is not an attempt at deception. Nevertheless, with these fabrics, the
actual weight is a reasonably reliable guide as to both its strength and its cost.
The unit of weight in the United States is ounces per "sailmaker's yard," which is 36" by 28.5".
The British use ounces per square yard, and Continental Europe uses grams per square meter. Thus
1 oz. American equals 1.26 oz. British and 42.8 grams per square meter.
Woven polyester can vary from a balanced weave where the yarns have
equal strength in both warp and fill directions to an unbal-anced weave
whose strength is concentrated in either the warp or fill direction. An
unbalanced weave that has more strength in the warp direction is called
"Warp-Oriented" and a weave with more strength in the fill direction is
called "Fill-Oriented." Extra strength is created by having stronger or more
yarns in the warp or fill direction. Simple cross-cut sails use fill-oriented dacrons because the
panels are perpendicular to the leech of the sail.
Laminates
More and more sailors are turning to laminated sailcloth because laminates are lighter for their
strength than Dacron. Laminates also have superior shape holding ability. As the name implies,
laminates all have some cloth or yarns glued to one or more layers of Mylar film. Laminates can be
made with any of the yarns listed on the chart on the following page.
The advantage laminates have over woven cloth is that the Mylar film reinforces in all
directions. Mylar has strength in all directions. The strength of woven cloth lies in the direction of
the yarns only. The Mylar film can vary in thickness from fractions of one mil to three or even four
mils. UK Sailmakers works closely with the cloth manufacturers to produce custom laminates that
are matched to the patented Tape-Drive® construction system. Your UK Sailmaker will be happy
to discuss sailcloth for your boat in detail.
Sailcloth Yarns
Grand Prix racers turn to PBO Zylon — PBO for short. The modulus of PBO is so great that it
makes any aramid yarns like Kevlar look stretchy. The material is extremely expensive and it
breaks down faster than Kevlar® when exposed to light. To shield it from harmful light, cloth
manufacturers are protecting the yarns with dyed mylar. Dimension/Polyant for example uses a
product called Magna Shield which is copper colored. Instead of using laminated with PBO, UK
Sailmakers uses this yarn more efficiently as Tape-Drive® tape only. That way its super strength is
used to carry the sail's primary loads.
Kevlar, Technora and Twaron are trademarks for aramid yarns which are the most common
high-tech yarn used in performance sailmaking. Dupont's trademarked aramids are called Kevlar®
and Kevlar® Edge™. Aramids have a distinctive brownish yellow color. Aramids have a couple of
drawbacks; they lose strength from flogging as well as from exposure to the sun's ultraviolet rays.
Technora Black, an aramid made by Teijin in Japan, is a material we have been making sails
with for the last five years, with outstanding results. Customers love its durability. Recently
Dupont introduced Kevlar® Edge™ yarn that has slightly better modulus to Kevlar® 49 and 25%
more tenacity than Kevlar® 49. That means this yarn will have the durability of Technora and the
same shape holding ability as Kevlar® 49. See the chart below..
Spectra yarns are lighter and more flexible than Kevlar® and Technora. Spectra doesn't break
down from folding, is impervious to UV radiation, and gets softer with use. Unfortunately, Spectra
is more expensive than Kevlar® . Other sailmakers have problems working with Spectra because it
elongates after staying under high loads. Used as a skin fabric in UK's Tape-Drive® construction
system, the Spectra fabric never becomes loaded enough to elongate.
Another new yarn is made of PEN fibers (Polyethylene Napthalate). It is most commonly sold
under Challenge Sailcloth's tradename Pentex. Stan-dard Polyester (Dacron) is short for
polyethylene terepthalate or PET. PEN fibers have the identical initial breaking strength as PET
yarns, but PEN fibers have 2.5 times less stretch than polyester yarns. Tape-Drive® tapes and
laminates made with PEN fibers greatly improve the performance of our budget-priced TapeDrive® sails.
Construction Methods
Almost every sailmaker designs sails on a computer, but the trick is building a sail that will
keep its intended shape. UK Sailmakers can offer the option of building sails with the patented
Tape-Drive® con-struction system as well as with the standard radial and crosscut layouts. This
flexibility ensures that you get a durable sail that is custom-designed and built.
You have probably noticed that there is considerable variation in how panels are arranged in
modern sails. These variations result from the fact that sailcloth is most resistant to stretch when
the yarns are in line with the loads in the sail. Because the loads change direction from place to
place within a sail, sailmakers arrange the panels to keep the stronger threadline aligned with the
loads, particularly in the leech area where the greatest loading occurs. With smaller, less heavily
loaded sails, fabrics can be selected which are adequately strong in all directions, tending to
eliminate the need for the more complex and costly panel layouts.
Tape-Drive®
UK Sailmakers uses a patented method of construction called
"Tape-Drive® " for high tech sails that hold their shape longer than
any others on the market.
Tape-Drive® is a patented two-part construction process in
which the structural strength of the sail and the skin that defines a
sail's three-dimen-sional shape are separate elements. In this unique
process, Tape-Drive® marries a grid of high strength, low stretch
tapes (the structural strength) to a three-dimension-ally shaped
membrane (the fabric or skin). The grid carries the primary
structural loads of the sail, while the membrane produces
aerodynamic lift. The tapes, with breaking strengths up to 1900
pounds, radiate across the sail with a heavier concentration at the
predicted high load areas, the corners and along the leech.
TapeDrive® is the only high-tech construction method in which the
materials can be varied to suit the specific use of the sail.
Depending on the size of your boat and its sail requirements, we
select the appropri-ate membrane material from a wide variety of
custom designed laminates using scrims of Kevlar® Edge™,
Technora, PBO Zylon, Pentex or polyester yarns.
Tape-Drive® offers many advantages to cruising and racing
sailors:
Tape-Drive® sails are up to 40 percent lighter than other high-tech
sails designed for similar wind ranges. Lighter sails mean less
pitching, less heeling, less weight in the boat, faster sail hoists, and
faster tacking. Tape-Drive® sails can be made lighter since the skin
material does not have to be load bearing.
Tape-Drive®
sails are also lighter because they do not require large, multi-layered
corner patches. With so many tapes coming together at the corners,
very little additional reinforcing is necessary.
Tape-Drive® sails are easier to fold, handle, and flake. They fold into small bundles, which means
that they take up less storage space.
Tape-Drive® sails set better in light air than conven-tional sails, due to the lighter weight material
and smaller corner patches.
Tape-Drive® sails have lightly stressed seams because the tapes span the panel edges; therefore,
the danger of seam failure is eliminated.
Tape-Drive® sails are easily repairable since the tapes prevent tears from running across the sail.
Holes and tears can simply be covered with sticky-back dacron.
Other Construction Methods
Crosscut Panel Layout:
A sail with all panels parallel to each other and perpendicular to
the leech. The cross cut layout is used for traditional mains and
genoas because it is simple, does not waste cloth, and it gives
sailmakers the most control over sail shape since all the seams are
shaped.
Cross-cut sails use fabrics with their greatest strength in the fill
direction to withstand the antici-pated loading along the leech of the
sail since the greatest loads in any sail are up and down the leech.
Fill-oriented fabrics are used in cross-cut sails because the stronger
fill yarns are parallel to the leech in a cross-cut layout.
Radial Panel Layout:
Radial cut sails are made with long narrow triangular panels
called gores which attempt to align the warp thread of the laminate
with the primary load paths of a sail. The laminated fabrics used in
radial sails have much more strength in the warp direction (that is
more yarns or stronger yarns running the full length of the roll of
cloth). In order to more precisely match the warp-oriented cloth
with the loads in the sail, the gores need to be very narrow. Wide
gores are used in low load areas, allowing sailmakers to use cloth
more economically.
Radial sails with their many panels allow sailmakers to use more
than one laminated fabric in a sail. Stronger laminates can be used
in high load areas like the leech and tack, while lighter cloth can be
used in the less loaded luff of the sail. A third fabric, one that is
heavy-duty and chafe-resistant, can be used in the foot panels to
stand up to the abuses of tacking and chafing on the life lines. By
mixing cloth types, sailmakers can make a lighter sail that has
strength where it is needed.
The gores radiate from the corners of the sail, because all loads
start from a corner and then run in arcs through the sail and end at
the other two corners.
The Sails -- Mainsails
There is occasionally some confusion with respect to mainsail area. Most sailmakers, including
us, compute mainsail area as if the sail were a right triangle with three straight edges. With this
method, area equals the luff times the foot divided by two. Most mainsails are, in fact, somewhat
larger than that by reason of the extra area at the leech, called roach, which falls outside the
straight line triangle. The promotional material distributed by boat builders and dealers sometimes
includes this extra area as part of mainsail area. If they’re using the same luff and foot dimensions,
they’re talking about the same sail in spite of the different figure for area. When we make
mainsails, we’ll include as much roach, not only on the leech, but also on the luff and foot, as is
practical and proper for the particular sail.
Shelf Foot and Loose Foot
The Shelf-Foot and Loose-Foot constructions are options that allow us to add a substantial
degree of extra fullness in the lower portion of the mainsail in order to improve racing
performance on reaches and runs. In very light air, the improved performance is achieved even to
windward. The extra fullness is removed by tightening the outhaul. When the outhaul is eased, the
sail maintains an airfoil shape down to the boom. With the Shelf-Foot option, a light piece of
material connects the sail to the boom. With the outhaul eased, the connecting material unfolds
and forms a shelf between the bottom of the main and the boom. When the outhaul is pulled tight,
the shelf closes up and lays against the side of the boom.
Loose-Foot construction does away with the shelf material. The sail is only attached to the
boom at the tack and clew. This attachment method is equally as strong as that of the foot attached
to the boom. Many boats are switching to Loose-Footed mains because they make it easier to bend
on your mainsail and to remove the sail from the boom — and it's less expensive.
Reefs
Mainsail reefs are used to depower a boat in strong winds. Reefing
makes the mainsail smaller. Each row of reefs consists of a heavily
reinforced patch with a grommet at the luff for the tack horn and a
grommet at the leech for the reefing outhaul. Between the reefed tack
and clew may be a row of evenly spaced smaller grommets (called
reef diamonds) to provide a means of gathering up and tying off the
excess sail. This row of holes is omitted in the case of a flattening
reef because there is not enough excess material to worry about. The
number of area-reducing reefs varies with the size and anticipated use
of the sail.
The Batmain
We use the term Batmain to describe a mainsail with full-length
battens, meaning the battens extend all the way across the sail from
leech to luff. Full-length battens have many virtues for cruising
sailors including better shape holding ability, longer life and easier
handling. The sails last longer because the full-length battens prevent
flogging — the violent snapping back and forth that happens when
you're tacking, reefing, hoisting or lowering your sail. As
conventional sails flog, the sailcloth breaks down, especially at the
front end of the battens where the leech of the sail “hinges” back and
forth. Flogging is the prime culprit in sail wear-and-tear. The fulllength battens induce a smooth airfoil shape to the sail, which
improves performance in all conditions. In light air the Batmain holds
a smooth airfoil shape instead of sagging like a wrinkled bed sheet.
Also, the Batmain won’t slat as the boat rolls in the waves. In
heavy air the Batmain doesn’t flog when the sheet is eased out to
reduce heeling. The Batmain does not flail and snap when
depowered, the silence is a pleasant surprise. Full-length battens also
restrict the draft of the sail from moving aft in heavy air when sailing
upwind. Downwind, the full-length battens hold out the leech of the
main giving you more pro-jected sail area.
All major rating rules, IMS, MORC, and PHRF permit sails with
full-length battens with no rating change at all. If your current main is
in good condition, its life can be extended by adding full-length
battens.
The Powerhead Main
The Powerhead main is our long-life racing design. Whether you are
buying a Tape-Drive, Tri-Radial or Cross-Cut main, the Powerhead’s fulllength top batten gives you many of the durability benefits of a full-batten
main (UK’s Batmain), while offering performance benefits. The
Powerhead gives you more control over the shape of your main, especially
the draft's depth and fore-and-aft positioning because the full length battens
prevent the sail from changing shape much. The Powerhead is easier to
trim than a full-batten main since the leading edge of the sail is free to luff.
And the Powerhead is a lighter sail than a Batmain since it uses shorter
battens and no special luff hardware.
The long top batten stabilizes the highly loaded head area, and stabilizes the leech allowing UK
to build a maximum-roach sail that gives you more sail area. The full-length top batten also
increases longevity by dampening the damaging effects of luffing and by preventing the draft of
the sail from moving aft over the years.
Along with the full-length top batten, Powerheads feature the new longer-length battens in the
lower positions. The longer battens support the leech better and eliminate a hard ridge that
sometimes develops at the inboard end of the battens as sails age. Powerheads that are used with
lazy jacks or the Dutchman ® flaking system can have the bottom batten full-length to help catch
the sail better as it comes down.
Genoas and Other Jibs
You'll notice that some of the jibs on certain price lists include a percentage
figure in their name and some do not. Examples are "150% No. 1 Genoa" and
"Working Jib." The percentage figure is a measure of overlap, sometimes called
an LP percentage. "LP" is another term from the rating rules, like "I" and "J." It is
the acronym of Luff Perpendicular and designates the shortest, or perpendicular,
distance from the clew to the LP or Luff Perpendicular Shortest distance between
clew and luff. luff of the sail.
If the luff of the sail is considered to be the base of a triangle, then LP is the
height, and the area is the base times the height divided by two, or one half of LP
times the luff length. LP is often expressed as a per-centage of the base of the
foretriangle (the J measure-ment) and that is the percentage figure which appears
in a price list. For example, if J is 10 feet, a 150% genoa will have an LP equal to
150% of 10, or 15 feet. Its area in square feet will equal 15 times its luff length divided by two.
The luff length is not specifically shown on price lists although we do show the area of every
sail. To calculate these areas, the computer uses a "maxi-mum available luff length" equivalent to
the hypot-enuse of the foretriangle (the length of the headstay) less an allowance for the space
devoted to the shackles, splices and other hardware needed to secure the head and tack of the sail.
In the case of jibs with less than full-length luffs, time tested rules of thumb are used to
compute the areas shown. Where appropriate, these areas are chosen to comply with the
regulations of the Offshore Racing Council. The working jib, for example, is comfortably below
the maximum specified for a "Heavy Weather Jib". The storm jib also falls below the maximum
area specified for that sail. These regulations were promulgated for a racing environment, but they
nevertheless define a good, conservative standard for anyone on the water in a sailboat. As we
mentioned at the outset, none of these areas are carved in stone; changes can always be made in
any case to fit particular situations.
Occasionally a price list may show a choice of areas for the No. 1 genoa, a circumstance which
possibly can cause confusion. It should be understood that the term "No. 1 genoa" is nonspecific as
to size. It denotes the largest genoa on the boat, whatever size that may be. (The next step down in
size becomes the No. 2 and so forth.) The size of the No. 1 is based on factors such as the weather
conditions in which the boat is to be sailed, the size of her rig, the applicable rating rule, if any, the
owner's requirements, etc. Obviously, the size of the No. 1 is one of the factors involved in picking
the size of the No. 2. For instance, if the chosen No. 1 has an LP of 150%, an appropriate No. 2
might well be 135%. On the other hand, some older boats are short rigged by today's standards and
would do better with a 170% No. 1. In that case a more appropriate size for the No. 2 would be
about 150%.
At the level of the No. 3 genoa, the variations in size tend to become minimal. In almost all
cases, a good No. 3 is a full length luff sail with an LP in the 100% range. This sail is a real work
horse in the inventory and is usually added before a No. 2.
The Passagemakers
The Passagemaker Genoas are cruising genoas with
all the options for roller reefing. UK Sailmakers offers
this popular sail in three different constructions. All
three are designed to retain their aerodynamic shape
when reefed by using a foam luff pad. The most
common size Passagemaker has an LP of 135%, but
they can be made to any size. All three Passagemakers
come with reefing reinforcements so that they can be
partially furled without unduly stressing or distorting
the fabric. In short, they are reasonably priced, durable,
easily handled, multipur-pose cruising genoas.
The Passagemaker I is a Dacron sail and the
Passagemaker II is lighter-weight alternative. The
Passagemaker II is made with UK's Tape-Drive®
construction system.
The Passagemaker II is the ultimate sail for the
cruising sailor who wants a sail designed to reef and keep its shape over a great range of wind
conditions and sail configurations. Its lighter-weight construction makes a sail that is light enough
to set well in light air, while strong enough to hold together in heavy air.
Spinnakers
The curved sides of a spinnaker make the computation of area a
complicated process. It is therefore an almost universal practice in the
sail-making industry to compute the area as if the sail were a rectangle.
We follow that practice, and the area shown on a price list is the product
of the luff length times the maximum width. The actual area will vary
from about 70% to 85% of the rectangular area, de-pending on the type
of spinnaker.
The length of the luffs and the maximum width are computed from
the I and JC dimensions in accordance with a formula which is common
to almost all of the rating rules for handicap racing. This formula yields
dimensions which have worked well in practice for many years. For that
reason, we use those dimensions in building spinnakers, even if the
particular customer has no intention of racing his or her boat. For those
interested, the maximum width equals 1.8 times JC, and the maxi-mum luff length equals 95% of the
square root of the sum of I squared and JC squared.
Three basic spinnaker types are available: Tri– radials,
Fatcats and Matrix Cuts. All three have radial heads and radial
clews. The Tri–radial and the Fatcat both have horizontal
panels in the center section, separating the head from the radial
clews. These horizontal panels are cut with curved edges to
permit proper control of the draft of the spinnaker. The
Fatcat differs from the Matrix and Tri-Radial in that it is
designed to be very flat for close reaching. The break point
between the bottom of the head panels and the top horizontal panel occurs much lower in the sail,
and the total surface area of the sail is less, especially in the head. As a consequence, a Fatcat
usually has fewer horizontal panels than a standard tri-radial for the same boat. It is normally made
of stronger, heavier material, and it doubles nicely as a "chicken chute" for heavy weather running.
The Matrix Cut is a variation of the tri-radial. It omits the horizontal panels altogether; the
radial clews are extended up to the middle of the sail, where they meet the head. The full radial
panel layout allows for precise articulation of cloth threadline to match primary sail loadings. Each
panel is shaped individu-ally by our computer cutting machines to distribute shaping smoothly and
evenly, with a minimum number of horizontal seams. Fewer seams make a smoother surface for
the wind to flow over. The Matrix creates the lightest, strongest spinnaker for a given cloth weight.
The rocked vertical panels ensure a distortion-free sail, even when close reaching.
Asymmetrical Spinnakers
For most sailors asymmetric spinnakers are specialty sails that fill in the
performance gap between genoas and spinnakers. On the growing new
breed of light-weight sport boats that carry retractable bowsprits,
asymmetrics are the only chutes carried.
As the graph below shows, there is a gap between the apparent wind
angle when a genoa is at the peak of its power and where a spinnaker is at
the peak of its power. Asymmetrical spinnakers fill this gap much better
than a genoa designed for reaching or a flat symmetrical spinnaker.
Asymmetrical spinnakers have been in use since the 1970s when UK
Sailmakers's Owen Torrey invented the Flasher — the asymmetrical poleless cruising spinnaker. For over a decade they've been used on lightweight
dinghies like Australia 18-foot skiffs and racing multi-hulls. But it has only
been recently that asymmetrical spinna-kers have been legalized for racing
on more mainstream boats.
The graph shows that the flatter asymmetrics, which fly closer to the boat, are best at tight
angles, while fuller sails that lift and fly out away from the boat are better at the wider angles. The
graph shows some other interesting points:
There is a trade-off between pointing and power. Flatter sails can be carried at narrower angles,
but ultimately they don't develop as much driving power as the deeper sails. Any sail produces
greater power when eased slightly from its closest possible angle of trim. At wider angles the
performance falls off gradually. At narrower angles the performance falls off quickly, particularly
in the flatter sails.
Generally, most sailors will benefit from our All Purpose shape, which is a compromise
between the flattest and fullest shapes.
Cruising Spinnakers (The UK Flasher)
The UK Flasher ® is an asymmetrical pole-less spinnaker that
combines the ease of handling of a jib or genoa with the pulling
power of a spinnaker. Because the generic name is so long, and
because it improves a boat's light-air downwind speed so much,
we named the sail "The Flasher ® . "
The Flasher ® is offered in two different construction styles.
The original design has long radial head panels surmounting a few
horizontal bottom panels, and it is an inexpensive sail to produce.
The tri-radial version is designed for the loads created by bigger
boats. It's tri-radial construction aligns the strongest threads of the
nylon material with the loads coming off the corners of the sail.
Both style Flashers ® look and perform like a spinnaker, but they
require none of the expensive extra gear needed for a spinnaker —
no pole, no track on the mast, no pole lift, no foreguy and no
afterguys. In short, with the addition of a spinnaker halyard, a
Flasher ® can be set and used on any boat equipped to set a jib.
The Flasher ® is made with lightweight nylon spinnaker cloth
that comes in many different colors which you can use to create
your own color scheme. system, any sailor wanting to sail upwind
needs to have an inboard fore-and-aft track for the jib sheet leads.
Also, racing sailors and cruising sailors both benefit from having
an adjustable lead car system that can move the lead while under
load. Cruisers with roller/furling systems need to move the lead
forward as the genoa is reefed; likewise, the lead has to be moved
aft when the sail is unreefed.
Dousing Sock (The UK Stasher)
The simplicity of the UK Flasher ® is further enhanced by
the addition of the UK Stasher. The UK Stasher is a sleeve that
gives you complete control over the Flasher ® when setting or
dousing the sail. The unique design of UK's Stasher offers
advantages over all other manufactured dousing socks (see
drawing for construction details). Pulling on the control line
raises the sleeve to the top of the sail, allowing it to fill and set.
A pull in the other direction encases the Flasher ® in the sleeve,
which permits trouble-free lowering of the sail. Singlehanded
ocean racers could not fly a spinnaker without a dousing sock
like the Stasher.
Staysails
The term "staysail" denotes any one of a large variety of what might be
called auxiliary or supple-mentary sails. Cruising sailors are most apt to carry
a forestaysail, which is a smaller jib hanked onto an intermediate forestay. Its
tack is set on the center line of the foredeck about a quarter of the way back
from the headstay to the mast, and it's best set from an intermediate halyard
about three-quarters of the way up the foretriangle. The advantages of a
double-head rig are great. When close reaching, you can get extra speed, and
in heavy air you can reduce sail area while keeping the helm balanced by
flying a smaller headsail off an intermediate stay close to the mast with a
reefed main. Another advantage of flying sails off an intermediate forestay is
that in heavy weather crew members don't have to venture all the way out to
the end of the bow, where the deck is narrowest and the waves come
aboard. The forestaysail can also be used under a genoa or reacher as part of a double-head rig.
The sail is most effective when the apparent wind angle is from about 45 or 50 degrees to 75 or 80
degrees off the bow.
The most common racing staysail is the "Dazy Staysail", which is a tall, narrow, very light sail
used under a spinnaker when the apparent wind direction is within a range from 5 or 10 degrees
forward of the beam to 20 or 25 degrees behind the beam. The sail is intended to have its tack set on
the center-line of the foredeck about one quarter to one third of the way back from the headstay to
the mast. Its luff length is as great as will fit between that tack position and top of the foretriangle.
Its width, or LP, is about 80% or 85% of J. A wider sail would have greater area, but would not be as
effective over as great a wind speed range or within as large a range of apparent wind angles.
The Dazy is effective not only because of the area it adds to the sail plan,
but also because it increases the air flow along the leeward side of the main,
thus improving the efficiency of that sail as well.
Both of these staysails are set flying, meaning they are not attached to or
supported by any stay. Consequently, their luff ropes must be made of a non–
stretching wire or, in some cases, Kevlar.
A bit of trivia: The Dazy staysail is named after the boat that popularized it.
On her way to winning the 1975 Canada's Cup, Golden Dazy used a tall
narrow staysail.
A Drifter is a full-draft, lightweight nylon No. 1 genoa that does
away with the frustration and aggravation of sailing in light air.
Drifters are a hybrid designed specifically for cruising sailors. Its
wind range is from 1-15 knots when the apparent wind angle is 3090 degrees. It can be used on a run when set wing-and-wing with a
whisker pole.
A Drifter is even easier to use than a cruising spinnaker since
the sail has the same profile as a genoa. UK can custom-make the
luff attachment of a Drifter to fit your furling system, to be used
with hanks or set flying. Like a spinnaker or a cruising spinnaker,
you have a choice of many colors to mix and match.
Blast Reachers
A “Blast Reacher” is a sail which is intended primarily for sailing with the wind forward of the
beam, but not so far forward as to be sailing on the wind. Its draft is therefore noticeably greater
than that of a genoa, or even a drifter, and the draft is positioned further aft in the sail. It has a very
high clew so that it can be set properly with the sheet eased, something a low-clewed genoa can’t
do as well. The high clew also keeps the foot out of the water in big waves. Unlike a drifter, it is not
primarily intended for use in light air. As a matter of fact, because today’s special purpose
spinnakers will outperform a reacher in light air, the reacher comes into its own only when the wind
gets stronger. For that reason, an appropriate fabric weight is about the same as, or slightly heavier
than that of an all purpose No. 1 genoa.
Some sailmakers have in the past offered a sail called a “reacher–drifter,” purporting to combine
the functions of both sails in one. We do not, because the characteristics we have described for each
are mutually exclusive, rather than compatible.
Storm Sails
UK Sailmakers builds storm sails to the requirements of the Offshore Racing Council. The
ORC requires racers to carry three storm sails: a storm trysail, storm jib and heavy weather jib. The
storm trysail and storm jib must be made out of strong dacron.
Storm Trysail: A short triangular sail that is attached to back of the mast and is sheeted to the
deck. The area of the storm trysail cannot be more than 0.175(PxE). The ORC states, “It shall be
sheeted independently of the boom and shall have neither a headboard nor battens and be of
suitable strength for the purpose.” If you ever plan to set a storm trysail, it is best to have a
separate track on the mast for the sail. In a gale, the last thing you want to do is remove the
mainsail from the mast to bend on the storm trysail.
Storm Jib: Its area is limited to five percent of the height of the foretriangle squared. The rule
states that the luff of the storm jib must be shorter than 65 percent of the height of the
foretriangle. Heavy Weather Jib: Its area is limited to 13.5 percent of the height of the
foretriangle squared. The ORC rules state that this sail cannot have reef points. If either the storm
jib or heavy weather jib are made to fit a luff-groove device, the sail must have an alternative
means of being attached to the stay. The most common alternative method is to have grommets
along the luff so that you can tie the sail to the stay.
Mainsail Trim
Mainsails must perform over a wide variety of sailing conditions.
This required versatility is achieved by adjustment and trimming.
The mainsail can be adjusted to vary the amount and location of
draft, and trimmed to control the shape of the leech and its angle to the
wind. While bewildering verbiage is sometimes used to describe this
process, we are doing only three things to the sail:
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1. Adjusting the tension on the three edges.
2. Adjusting the shape of the leading edge if mast bend is
possible.
3. Trimming the boom in and out.
Here’s a brief explanation of terms dealing with mainsails:
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DRAFT: The amount of curvature in the sail. Sometimes called
depth, draft is measured along a straight line running between the leech and the luff.
DRAFT LOCATION: The point where the draft is the greatest, measured along a straight
line running between the leech and the luff.
LEECH SHAPE: The straightness or curve of the leech.
The mechanics of attaining proper mainsail characteristics vary according to class rules, rating
rules, and personal preference. The basics of control are:
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LUFF TENSION: Controlled by the halyard, Cun-ningham, and boom downhaul if the boat
is equipped with one.
FOOT TENSION: Controlled by the outhaul and flattening reef.
LEECH TENSION: Controlled by the mainsheet and traveler upwind, and by the boom
vang off the wind. The leech line is used primarily to remove flutter from the very edge of
the sail.
MAST BEND: Controlled by various combinations of the backstay, babystay and running
backstays. Blocks of wood or hard rubber can also be used to chock the mast where it goes
through the deck to control bend.
TRIM: Controlled by the mainsheet and the traveler. Although closely interrelated, each
control has a distinct effect on the mainsail’s characteristics. It is instructive and fun to
work the controls and observe the effects
LUFF TENSION
Increased luff tension moves the draft forward.
Decreased luff tension moves the draft aft.
TO ADD LUFF TENSION:
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1. Increase halyard tension until the headboard reaches the upper black band.
2. Pull down the main boom downhaul until the lower black band is reached.
3. Put tension on the Cunningham.
FOOT TENSION
Increased foot tension removes draft from the sail.
Decreased foot tension adds draft to the sail.
TO ADD FOOT TENSION
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1. Tighten the outhaul. Note: The effects of foot tension are most pronounced in the lower
third of the sail.
LEECH TENSION
Increased leech tension straightens the leech and cups the sail.
Decreased leech tension eases the leech and twists the sail.
TO TIGHTEN THE LEECH:
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1. Trim mainsheet harder when sailing on the wind.
2. Tension boom vang when sailing off the wind.
3. Tighten leech line to control leech flutter.
TO EASE THE LEECH:
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1. Ease tension on mainsheet and boom vang. When beating in light winds, you’ll need to
pull the traveler above the center line in order to trim the mainsail close enough while
keeping the upper leech open.
2. Ease the leech cord.
3. In very light air, reduce the effect of the weight of the boom by tightening the topping
lift.
MAST BEND
Bending the mast decreases the draft in the sail, it flattens the sail.
Removing mast bend adds draft to the sail.
TO BEND THE MAST:
1. Tighten backstay.
2. Tighten baby or midstay, or forward lowers.
TO STRAIGHTEN MAST:
1. Ease backstay and/or tighten headstay.
2. Ease babystay and/or forward lowers.
3. Tighten running backstays and/or after lowers.
Before working on sail shape and trim, check these points:
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1. Battens should be straight with the flexible end forward and the back end snug against
the pocket. The most flexible batten should be in the top pocket.
2. Telltales should be installed on the leech near the top two battens. Additional telltales
midway between the luff and the leech are also useful.
3. Check mast tune with the main and jib set. Some bend aft is desirable, while there should
be no bend to the side.
Variations in wind velocity, wind direction, and sea state require the mainsail to be very
adjustable. Experimenting will help you get the best results on your own boat, but these general
principles should be kept in mind.
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1. Sailing upwind requires a flatter sail than reaching and running.
2. Rough water requires a fuller setting than smooth water.
3. Light winds require a fuller setting than strong winds
Genoa Trim
The major characteristics of genoa, or jib shape, are the amount and location of draft, and the
angle of entry. The shape of the jib is controlled by the fore and aft location of the jib leads, luff
tension, sheet tension and headstay tension.
LUFF TENSION: Tension on the leading edge of the sail is controlled by jib halyard and by jib
Cunningham. The principal effect of luff tension is to position draft in the sail. Increased luff tension
moves draft forward. Decreased luff tension moves draft aft.
LEAD POSITION: Most boats have provisions for moving the jib sheet lead block fore and aft. The
position of the lead controls the tension on the leech and the foot, as well as the draft location in the
upper and lower portions of the sail:
Jib lead aft moves the draft in the top of the sail forward and moves the draft in the bottom of the
sail aft. With the lead aft, the leech is loose and foot is tight.
Jib lead forward moves the draft in the top of the sail aft and moves the draft in the bottom of the
sail forward. The leech is tight and the foot is loose.
The correct jib lead position distributes draft evenly in the sail and the tension on the leech and
foot are relatively equal.
Jib leads can be located by observing which portion of the sail begins to luff first.
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Luffing in the upper portion means that the lead should be moved forward.
Luffing in the lower portion requires the lead point to be moved aft.
SHEET TENSION: Along with controlling the angle to the wind (trim), the jib sheet controls the
amount of draft and twist in the jib. A tight jib sheet will remove draft from the sail; easing the sheet
will add draft to the sail.
HEADSTAY TENSION: The straightness of the headstay is controlled by tension on the backstay
on a masthead rig or by running backstays on a fractionally rigged boat. The looser the headstay, the
more the middle of the stay sags to leeward and astern. Increased tension reduces the draft of the
genoa and flattens the entry angle. Decreased tension increases the draft and creates a rounder entry.
JIB SHAPE: Variations in wind velocity, wind angle, and sea conditions make adjustments in jib
shape desirable. The following adjustments can be made to adapt to changing conditions.
CHANGING WIND VELOCITY: Decreased velocity requires more draft in the sail. A fuller sail
creates more power. As the wind increases, you flatten the sail. To help understand this, think of an
airplane; to create lift at slow speeds, a pilot lowers the flaps , which creates more draft in the wing.
Once up to speed, the flaps come up and the wing gets flatter. In-creased velocity calls for decreased
draft.
Another adjustment you have to make as the wind increases is increased amounts of halyard
tension. As the wind blows harder, the draft of the sail gets pushed aft. By increasing halyard
tension, you return the draft back toward the middle or forward third of the sail where it belongs.
Some boats can move the draft forward with a jib Cunningham.
CHANGING WIND DIRECTION: When the wind goes forward so that you are sailing on a beat or
a close reach, less draft and a flatter entry angle are required for pointing ability. When the wind
goes aft, additional draft and rounder entry are required for added power.
CHANGING SEA CONDITIONS: Rough sea conditions make a slightly fuller sail with a rounder
entry angle desirable. In smooth seas you trade power for pointing by flattening the entry angle.
Modern, easily driven boats can trade speed for pointing especially if they have a tendency to be
overpowered in heavy air. This means setting the boat up with less draft and a flatter entry angle. A
flat entry angle lets you point higher, but the sail stalls out easier. To power up the sails in light
winds or in choppy seas, tighten the jib halyard to move the draft of the jib forward, which also
increases the entry angle. A rounder entry angle will also make it easier for a less-than- attentive
helmsman to keep the boat going fast since the sail will not stall as easily.
Even on top racing boats, when a new person takes the helm, they usually ask for more halyard
tension, which produces a rounder entry angle, to make it easier to keep the boat sailing in the
groove. After they get the feel of the boat in the current conditions, then they ease the halyard
slightly for higher pointing.
SHEETING THE SAIL
Once the shape is set, the sail can be trimmed to the desired angle to the wind. Two controls are
available: jib sheet lead position and jib sheet tension. Jib sheet tensioning will be covered in the
following section on using telltales.
On many older boats, the only jib or genoa sheeting point available is a lead block on the toe rail.
While some cruising sailors may be content with this As the wind velocity increases when beating
and the boat starts to heel too much, the lead should be moved progressively aft on the inboard track
to reduce heeling. Heeling is reduced by moving the lead aft because the top of the genoa is allowed
to twist off and luff. The top of the sail luffs because the jib sheet is pulling the sail back more than it
is pulling it down. (See diagram below.) Pulling the lead aft also flattens the lower section of the
sail. Flatter sails produce less heeling moment.
As the wind velocity decreases, moving the lead forward adds draft to the sail, which makes it more
powerful.
In wavy conditions on a beat, move the lead outboard to a block on the toe rail to increase drive at
the expense of pointing. The boat needs power to get through the waves.
After a while, you will find an average point on the track where you will keep the lead for each
genoa in your inventory. Mark these positions so that you can quickly set the lead. Any adjustments
you make from the average position will then be fine tuning. The most common ways of marking
lead positions are with stick-on numbers or a magic marker. Place the number “1” where the No. 1
genoa sheets to, and a number “2” and number “3” where they sheet to if you have those sails.
Cruising sailors with roller/reefing genoas need two marks on the track; one mark aft for when the
genoa is rolled out all the way, and one mark forward for where the lead should be when the sail is
reefed to the reef point on the foot (which all UK Passagemaker genoas
have).
As the wind angle frees up from a reach to a run, move the lead outboard and forward to a block on
the toe rail, assuming there are attachment points on your rail for this. The lead moves outboard to
open up the slot between the jib and the main, and the lead goes forward to counteract the tendency
of the sail to twist. With the jib shaped to the conditions, and the lead located in the best position, the
sheet is trimmed to control the sail’s angle to the wind. When sailing to windward, the spreaders
provide a good reference point. Experimenting with a sensitive speedometer or with another boat
will show how close the sail can be trimmed in given conditions.
When sailing off the wind, set a course, then ease the jib to the point of luffing, or until the inside
telltales stop streaming aft. Then trim slightly. If the leads have been set for windward sailing, they
will have to be moved forward to counteract the tendency of the sail to twist.
Sailing to the Telltales
No indicator has been developed that approaches the sensitivity and effectiveness of telltales
along the luff of the jib. These yarns or “ticklers” monitor the flow of wind across the sail.
Telltales are used for fine-tuning your genoa sheet trim and to fine-tune the course you are
steering. Telltales are only an aid when the sail has wind flow across both sides, i.e., when sailing
angles between beating and beam reaching. When sailing lower than a beam reach, the sail is
catching wind instead of working like an airfoil.
Telltales come in pairs, one on each side of the jib. The best set up is to have three sets evenly
spaced along the luff so that you can see how the wind is flowing at different heights of the sail.
Telltales should be anywhere from six inches to 18 inches aft of the luff, depending on the size of
the boat — the bigger the sail, the further aft the telltales should be. Also, the farther forward they
are, the more sensitive they are.
All UK Sailmakers sell inexpensive packets of green and red telltales that stick on to your sail.
When applying telltales, always put the starboard one of each pair higher than the port one. This
will help you figure out which is which when reading the telltales from the cockpit. The most basic
way to read telltales is to get the yarns on both sides of the sail streaming straight back. If the
leeward one stops streaming, head up and sail closer to the wind. If the windward one stops
streaming, fall off. When the yarn streams straight back, it tells you that there is attached flow over
the sail at that particular point. If a telltale stops streaming and hangs limp, there is no air flow and
that side of the sail is stalled. If the telltale dances around, flow is turbulent.
By concentrating further on interpreting the telltales, you can get even more information. The
following are four different “settings” for telltales:
1. Bow-down Speed-building Mode: Leeward telltale dances and windward telltale streams straight back. This mode is used for building speed
when coming out of a tack or when going through steep motorboat chop.
2. Max Speed Mode: Both telltales streams straight aft.
3. Pointing Mode: Leeward telltale streams aft, and windward telltale
dances between straight back and 45° above horizontal. This mode is used
when sailing to windward in flat water in winds over 10 knots.
4. Pinching Mode: Leeward telltale streams aft, and windward telltale
stands straight up. To be used when trying to get over another boat or make
it around a channel mark.
TELLTALE PERSPECTIVE
When sailing to windward, the degree of course change between “Bow-down Speed-building
Mode” and the “Pinching Mode” should be about 5 to 7 degrees. If the telltales go from one
extreme to the other after a two-degree course change, put a bit more tension on the luff. The
rounder entry angle will broaden the gap between stalled from sailing too high and stalled from
sailing too low.
Remember not to sail with the telltales in the pointing or pinching mode in light winds or in
wavy conditions. The boat will lose too much speed. In heavy winds when the boat is
overpowered, you can reduce heeling by heading up into the pointing mode.
Use your telltales to fine-tune your lead position. With three sets of telltales along the luff,
you’ll be able to shape the jib like a trimmer on an America’s Cup contender. In general, on a beat
the lead is in the right place when the lower two sets stream straight back and the inside upper
telltale dances about 45 degrees above horizontal.
Spinnaker Setup and Trim
The steps in preparing to set a spinnaker and their most efficient sequence varies depending upon the
boat, the crew and the conditions. The basic steps and their sequence are:
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1. Attach the turtle. On boats under 30 feet, it can be clipped in the bow pulpit. On larger
boats (and small ones when it’s blowing hard) the turtle should be hooked at the rail or to the
middle of the foredeck about halfway between the mast and headstay. Make sure that the
head and both clews are outside of the bag.
2. Position the spinnaker pole so that the out-board end of the pole is over the side of the boat
that will be the windward side when the spinnaker is hoisted.
3. Lead the guy through the outboard end of the pole and then attach it to the spinnaker.
4. Fasten the sheet to the sail. Double-check to be sure that it is not tangled with the life lines.
5. Attach the pole to the mast and raise the inboard end of the pole to the height which seems
appropriate.
6. Attach the topping lift and foreguy and hoist the pole at right angles to the mast.
7. Attach the spinnaker halyard.
When racing and the boat is heeling over, it’s important that the bowman keep his or her weight
to windward while setting up the spinnaker. To do this, the bowman has to break up the jobs listed
above, and do them on two different tacks. For instance, when rounding the windward mark to port,
have the bowman clip the spinnaker bag to the port rail while on your final port tack to the mark.
This way he can hook on the turtle and attach the sheets and guys while on the windward side. When
you tack to starboard, he can get the pole ready while keeping his weight to windward. If he has to
do any of the rigging at the bow, he should plan out his moves ahead of time so that he spends the
least amount of time possible on the bow, i.e., if he has to lead the sheets around the forestay, have
the cockpit crew make sure the lines are untangled so that they’ll run free when he pulls on them.
Weight on the bow, no matter how light, disturbs the helm.
THE SET The sequence of the actual set depends on whether the spinnaker is set flying or
stopped in rubber bands. In either case, do not to trim the chute fully until the halyard is hoisted and
cleated.
TO SET FLYING
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1. Trim the spinnaker guy so that the clew of the spinnaker reaches the jaw of the pole when
the pole is laying against the headstay.
2. Trim the spinnaker sheet until the clew is just past the shrouds.
3. Hoist the spinnaker all the way up, then drop the jib.
4. Trim the spinnaker to the wind.
TO SET STOPPED Having the sail stopped in rubber bands is some-times used when setting a
spinnaker in heavy winds. The rubber bands keep the sail under control and break away when your
crew trims the sheet.
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1. Trim the spinnaker guy so that the clew of the spinnaker reaches the jaw of the pole when
the pole is laying against the headstay.
2. Trim the spinnaker sheet until the clew is just past the shrouds.
3. Hoist the sail until it is all the way up.
4. Over-trim the sheet to break open the stops.
5. Trim the sheet and the guy as required by the wind, starting with the guy first.
6. Drop the jib.
TRIMMING THE SPINNAKER
The tools available for maintaining the proper trim of a spinnaker are limited; they consist of
pole position and sheet position. Pole position is variable both fore and aft and up and down. Sheet
position is varied primarily by pulling it in or letting it out. Normally, the sheet is led to the leeward
rail, at or near the stern, but sheet position can also be varied by the use of a spinnaker twing (a
block and tackle that changes the lead angle of the sheet). A forward lead is only recommended
when running in strong winds to help stabilize the spinnaker.
The spinnaker is a versatile sail which can be used when the wind is blowing anywhere from 60
to 180 degrees off the bow. Optimal sailing angles are determined by wind strength. In stronger
winds, you won’t be able to fly the spinnaker as close to the wind because your boat will be
overpowered by the spinna-ker at the closer angles. If the wind is too light, sailing at the broader
angles will be too slow.
At the forward end of this range, from 60 to 130 degrees, the wind will be flowing across the
spinnaker from the luff to leech. (The principles involved in trimming a genoa are also applicable
here.) At some point behind 130 degrees, or thereabouts, the wind blows directly into the sail and
ceases to move across it. The sail is then said to be “stalled”, and the principles of trim change
accordingly.
REACHING TRIM
When the wind is flowing across the spinnaker from luff to leech, reaching considerations apply.
If the wind is forward of abeam, the pole should be close to the headstay. “Close” means as close as
possible to the headstay without allowing the two to touch. If the pole does rub against the stay,
there’s a risk of damage to the pole, the rig, or both. Fore and aft position is controlled by the
afterguy. The sheet should be trimmed just enough to prevent the sail from collapsing. The trim
should be constantly tested by easing the sheet slightly until the luff commences to curl, then
trimming again when the curl becomes excessive.
Put telltales on the leeches of the spinnaker midway between the head and clews. When reaching,
read the telltales as you would on a jib. Keep both the windward and the leeward telltales streaming
straight back. When both are streaming aft, the leading edge of the chute will curl some — but don’t
worry. A little bit of curl is fast.
Pole height is adjusted by means of the pole lift and foreguy. In any given wind condition, the
clew will find its own height. It is commonly recommended that the pole height be adjusted to match
that found by the clew. In that condition, the draft will be approxi-mately in the center of the sail,
which is the right place for it. If the pole is slightly lower than the clew, the sail will become
asymmetrical, with the draft slightly forward of the center. This asymmetrical trim will be faster on
close reaches. Putting the pole higher than the clew moves the draft behind the middle. But this
always produces slow going: NEVER CARRY THE POLE HIGHER THAN THE CLEW.
At all times, sufficient tension should be maintained on the pole lift, the foreguy and the afterguy
to keep the outboard end of the pole firmly in position. When all other adjustments have been made,
the inboard end of the pole should be moved up or down on its track to keep the pole perpendicular
to the mast. Remember that adjustments to the inboard end are a low priority item. Unless it’s
grossly out of position, meaning feet, not inches, don’t waste time on it until everything else is set
correctly.
As the wind moves aft, ease the sheet, while at the same time bringing the pole aft. If the pole is
correctly placed fore and aft, the depth of the draft in the sail will be uniform from the top to bottom,
and the luff of the sail will extend directly upward from the end of the pole. If the pole is too far
forward, the pocket in the lower part of the sail will be too deep, and the luff will angle out to
windward from the end of the pole. If the pole is too far aft, the foot of the sail will be too flat, and
the luff will angle off to leeward from the pole end.
RUNNING TRIM
When on a run, with the wind blowing directly into the sail, it is
desirable to present as much area as possible, subject to certain
limitations. The pole should be kept as far aft as possible without
making the foot too flat or causing the luff to be other than straight
up from the pole end.
On a run, in a good breeze (you shouldn’t be on a run unless the wind is blowing over 14 knots),
the clew may seek to rise higher than is desirable. If the foot gets too high, you lose projected area.
Therefore, move the spinnaker sheet lead forward to keep the clew down. That way you won’t have
to raise the pole too high.
Even in a “stalled” sail, there is some flow of air along the leeward side of the sail and therefore
some aerodynamic force, which increases the wind’s normal force. This flow occurs at the sides of
the sail, moving from both leeches for a short distance toward the center of the sail. A flatter sail
projects more area, hampering flow on the leeward side of the sail. A fuller sail projects less area,
but generates more flow. A similar flow of air also moves over the top of the sail and down the front
toward the center. This overhead flow travels further and is more powerful than the flow atthe sides.
If the foot of the sail is held too low, this overhead flow will be curtailed; if not low enough, too
much projected area will be lost.
Proper downwind trim involves balancing the extra thrust resulting from the aerodynamic forces
acting around the edges of a deeper setting against the greater projected area obtained with a flatter
setting. Normally, best results are obtained at the flatter end of the range, but remember that it is
quite possible to trim the sail too flat or have the foot too low. Thus, the only way to find the best
shape is to experiment while watching your speedometer.
Spinnaker Jibes
Perhaps no sailing maneuver calls for better crew coordination than the spinnaker jibe. There
are two basic jibing techniques:
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1. Dip-Pole: This system is used on boats over 30 feet. It
utilizes two sheets and two guys attached to each clew of the
spinnaker.
2. End for End: This jibing technique is universally used on
one designs and is workable on boats up to 30 feet.
The Dip-Pole Jibe
With two sheets and two guys, this system converts the spinnaker
jibe from the classification of “To be avoided at all costs” to the point
where a practiced crew can handle a jibe with ease. The beauty of this
method is the strain of the spinnaker is taken with one set of sheets
and guys so that during the jibe the bowman can easily get the
unloaded new guy into the pole. The dip pole method works like this:
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1. When the call for the jibe comes, the mastman raises the inboard end of the spinnaker
pole up the mast so that when the pole swings through the foretriangle it will clear the
forestay.
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2. The spinnaker pole topping lift is lowered so that the outboard end is just above the bow
pulpit when it swings across the boat. (To ensure that the pole swings across the bow in the
same arc, jibe after jibe you need to mark the mast and the topping lift. The mast should be
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marked at the height that the inboard end of the pole reaches when it is raised, while the
topping lift is marked so that the outboard end of the pole may always be lowered to the
same position. )
3. The bowman goes to the pulpit with unloaded spinnaker guy in hand.
4. The helmsman turns the boat dead downwind.
5. As the boat turns, the spinnaker guy is tight-ened until the pole is perpendicular to the
centerline of the boat. Trimming the pole perpendicular like this rotates the spinnaker to
what will be the new leeward side of the boat.
6. When the boat is dead downwind, the skipper yells “Trip” which tells the mastman to
open the outboard jaw of the pole so that the guy flies free of the pole. (Make sure that the
pole is always set with the jaws facing up.) With the guy free, the sail is controlled by the
two spinnaker sheets.
7. The mastman pulls the pole to the bowman in the pulpit using the trip line.
8. As the pole comes over, the mainsail is swung over to the new side.
9. When the bowman gets the new guy in the spinnaker pole jaw, he yells “Made!” which
tells the person trimming the guy that he can now tension it. Once the guy is tensioned, the
old sheet is released.
10. Finally, the spinnaker is trimmed to the wind, the topping lift is raised and the inboard
end of the pole is lowered.
THE END-FOR-END JIBE
The end-for-end method is only viable on boats below 30 feet because the spinnaker pole becomes
free from the mast during the jibe. For the crew to handle the loose pole, the pole must be small
and light enough to be lifted and pushed into position.
During an end-for-end jibe, the pole is disconnected from the mast, and disconnected from the sail.
Free from the sail, the pole hangs from the topping lift. The end that was hooked to the mast is then
connected to the spinnaker sheet and the end that was hooked to the spinnaker guy is hooked to the
mast.
This system requires a bridle for both the topping lift and the foreguy so that neither require
trimming during the jibe. The pole should be attached to the mast with the jaws up.
The steps for an end-to-end jibe are as follows:
1. As the jibe starts, either the downhaul or guy is eased to facilitate removing the pole from the
mast.
2. The sheet is brought in close to the shroud where the foredeck crew can grab it.
3. The boat is turned dead downwind.
4. The pole is disconnected from the mast.
5. The guy is released from the end of the pole.
6. The old sheet is connected to the end of the pole that was on the mast.
7. The pole is pushed out and forward on the new windward side.
8. The pole is attached to the mast and the mastman yells made.
9. The cockpit crew trims the spinnaker to the wind.
Spinnaker Dousing
METHOD 1: LAZY GUY TAKEDOWN
The lazy guy takedown uses the idle guy on the leeward side to insure getting the spinnaker into the
mainsail’s blanket zone. The lazy guy is led forward and under the foot of the genoa. When the sail
is released from the pole, the lazy guy is quickly tightened and the spinnaker is gathered.
METHOD 2: RELEASING THE SHACKLE
The guy is eased until the pole reaches the forestay. Never let the pole smack the headstay, or you
may break the pole, the headstay or both. The pole is lowered until it can be reached easily by the
bowman who opens the snap-shackle that connects the guy to the spinnaker.
In this diagram the genoa is omitted to show the lazy guy brought forward to the fore-deck so that
the crew can gather the spinnaker by the lazy guy under the genoa. Lazy Guy
As the spinnaker is released from the guy, one or more crewmembers sitting to leeward of the main
pulls on the sheet and brings in the spinnaker. The halyard is eased quickly for the first third of the
distance, which collapses the sail. Once the chute starts coming aboard, the rest of the halyard is
eased as fast as the crew can gather without the sail falling in the water. Some racing crews prefer to
take the sail down into the forward hatch to keep the sail from getting tangled with the jib sheet.
METHOD 3: RUNNING GUY
This system is basically the same as Method 1, except that the guy remains attached to the sail. First
the guy is eased until the pole kisses the headstay, and then it is completely released as the crew
gathers the sail. Great care must be taken to make sure that the guy is completely clear, with no
knots, so it can run free. The sail is then gathered in the same location as in Method 1.
METHOD 4: STRETCH AND BLOW
This is a heavy air technique designed to depower the spinnaker. In this method, the foot of the
spinnaker is pulled tight, making it impossible for the corners to fall into the water. To keep the
clews out of the water and make the foot tight, the pole is eased forward to the headstay and the
spinnaker sheet is tightened as much as possible. After the foot is pulled tight, the halyard is cast off
and let run. The wind blows the sail parallel to the water allowing the crew to pull the sail in by its
leeches. If the sail does touch the water, it won’t be able to scoop up a lot of water if the two clews
are kept tight.
Using the Flasher®
The Flasher ® is UK’s trademark for an asym-metrical pole-less cruising spinnaker. The Flasher
® requires little in the way of equipment. Be sure, however, that what you do have is right for the job
and well-organized. The following is a list of the equip-ment you’ll need:
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SPINNAKER HALYARD: This halyard is different than a jib halyard since it either exits the
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mast above the forestay, or it is led to a block outside the forestay.
TACK PENDANT: The tack pendant length can vary. The simplest set up is to tie the
pendant to the stem fitting so that the tack of the Flasher ® is about four feet off the deck. For
those who like to tweak their sail trim, the pendant must be long enough to reach a winch in
the cockpit.
OPTIONAL DACRON COLLAR: The collar helps stabilize the Flasher ® . On boats with
roller/furling genoas, the collar reduces chafe by distributing the leeward tug of the sail.
SHEETS: The sheets should be twice the length of the boat. Any diameter line will be strong
enough, so choose one that is thick enough to be comfortable to handle, yet light enough for
good light air performance. If you are going to be trimming the sail with a self-tailing winch,
make sure that the line is thick enough for the self-tailer.
TWO SHEET BLOCKS: These blocks can be snatch blocks, fiddle blocks, or any other type
of block. Attach them to the aft corners of the boat.
THE STASHER: The optional Stasher (dousing sock) allows you to raise and lower the sail
in complete control. The Stasher is a sleeve that contains the sail as it is hoisted, sets it free
when you’re ready, and encases the chute when it’s time to douse.
FLASHER ® SET UP AND HOIST
First things first. Clip the Flasher ® bag to the deck or lifelines on the side of the boat from
which the sail will be flying. Many sail bags have been lost overboard by not taking this first step!
1. Cleat or tie the tack pendant so that the tack will be about four feet off the deck.
2. Pass the tack collar around your headstay and clip the hook to the O-ring. (Note: Your genoa
must be roller-furled or lowered at this point.) The collar holds the tack of the sail forward
while the pendant will hold the tack down.
3. Run the leeward sheet from the block on the leeward corner of the boat, outside of everything
(the lifelines and shrouds) and attach it to the clew of the sail. Make sure the sheet is never
led under the lifelines. Lead the windward sheet the same way, but be sure to pass it in front
of your headstay and over the bow pulpit before attaching it to the sail.
4. Finally, attach the halyard to the top of the Stasher pendant or directly to the head of the sail
if you are not using a dousing sock (see p.42 for Stasher set up).
To keep your Flasher ® under control when you hoist it, make sure your boat is headed on a very
broad reach with the mainsail eased all the way to the shrouds. This way you will be able to hoist
your Flasher ® in the mainsail’s wind shadow.
The final step before raising the Flasher ® is to trim the sheet so that the clew is one to two feet
forward of the shrouds. The trick in hoisting is to make sure the sail does not fill until the halyard is
up and cleated.
Trimming the Flasher
The Flasher ® can be flown just as you would a spinnaker, with the wind anywhere from about
75 degrees off the bow to dead-downwind.
REACHING:
Tightening the tack pendant moves the draft of the sail forward creating a stable and fast
reaching shape. Conversely, easing the tack pendant and raising the tack creates a better shape for
sailing at broader angles. The tack should always be set somewhat lower than the clew.
The sheet should be eased as much as possible without letting the sail collapse. This will insure
that the sail is at the optimum angle to the wind, and that the sails is as free as possible from the
mainsail’s blanket zone.
Once on course, ease the sheet until a curl appears along the luff of the sail. Then adjust the
tack pendant so that the clew is higher than the tack. As the wind moves aft, the sheet and tack
pendant are eased to keep maximum sail area projected and to keep the sail in the most efficient
shape.
RUNNING:
In winds under 15 knots, sailing dead downwind is slower than sailing at broad reaching angles
— regardless of sailing with a Flasher ® or normal spinnaker. You will sail more comfortably,
have better control, and get to your destination sooner if you jibe downwind.
Setting the Flasher ® with a pole is possible if you want to bother. Either a spinnaker pole or, a
lighter, longer, whisker pole will work. The easiest way to set up your Flasher ® wing-and-wing is
to attach the outboard end of the pole to the clew of the sail while it is still on the same side as the
mainsail, then jibe the main.
Jibing the Flasher
Jibing is easy when you follow a few tips.
Start the process by steering so that the wind is approximately 150 degrees over the windward quarter.Trim the mainsail tight so that the boom is over the boat (Photo 1).
Trimming the main tight is the trick to a smooth jibe, because the next step is to ease the
Flasher ® sheet until the entire sail is streaming out in front of the boat (Photo 2). If the main
is not trimmed tight, it blankets the Flasher ® , preventing it from being blown out in front of
the headstay.
Next turn the stern of the boat through the eye of the wind, jibing the boat. As you turn, the
boom comes across and the clew of the Flasher crosses to the new leeward side.(Photo 3)
Trim the Flasher ® and then ease the mainsheet (Photo 4)
THE FLASHER ® STASHER
The Stasher is a sleeve that contains the Flasher ® , allowing you to easily raise and lower
the sail under complete control. Your Flasher ® needs to be installed in the Stasher only
once. After that they stay together, whether in use or in the bag.
To install a Flasher ® in a Stasher, lay your Flasher ® out in a clean, open space with the
head at one end and the two clews together at the other. Pull the head up through the Stasher
sleeve and connect the Flasher ® to the shackle at the bottom of the wire pendant at the top of
the unit. The pendant allows the Stasher to sit above the head of your Flasher ® when not in
use.
USING YOUR STASHER
Once your Flasher ® is installed in the Stasher, the set-up is exactly the same as setting up
a Flasher ® without a Stasher. The only difference is that your halyard is attached to the top
of the wire pendant instead of directly to the Flasher ® .
To set, hoist your Flasher ® in the Stasher sleeve with the tack and sheet attached in the
normal manner. Be sure to leave some slack in the Flasher ® sheet while hoisting.
Once the Flasher ® is up and the halyard is cleated, stand near the bow, pull on the
Stasher halyard (a continuous line built into the sleeve, not to be confused with the spinnaker
halyard) and raise the sleeve so that it is completely above the Flasher ® .
At this point, trim your sheet as described previously. Once the Stasher is raised to the top
of the sail, secure the end of Stasher halyard to the mast to prevent it from dangling out of
reach.
To douse, turn downwind to blanket the Flasher ® with your main, ease the Flasher ®
sheet, and pull down on the Stasher halyard. Once the Stasher encases the sail, lower Flasher
® and Stasher together and put the combo in its bag. There is no need to repack the Flasher ®
for your next set. Just hook up and set. The Stasher is so easy to use, and offers so much
control over the Flasher ® , that some sailors use it to control the sail while jibing. Before
jibing, lower the Stasher over the sail, pull the sleeved sail around the forestay and then reset
the sail by raising the Stasher.
Tuning Your Rig
The first objective in tuning a rig is to get the mast centered in the boat and standing straight.
Once this is achieved, refinement of the tuning will improve the boat’s performance by changing the
balance of the helm and, more importantly, by controlling sail shape.
Tuning your rig is a two step process. The first part is done at the dock and the second part is
done while sailing. To start, pick a calm day, or find a sheltered spot to tie up. If the rig is already set
up, loosen everything so that you can start from scratch. It is a good idea at this point to lubricate all
the turnbuckles.
The first job is to set the rake of the mast. If you are putting the mast in the boat for the first time,
set the mast so that it leans back a few inches. More rake adds weather helm. Rake is achieved by
moving the butt of the mast forward in the step or the mast aft at the partners. If you’ve been sailing
the boat and the helm feels right, leave the rake alone. Be sure the mast is firmly set in the step and
solidly chocked at the partners. Use either very hard rubber or hardwood chocks. One of the best
ways to secure the mast at the partners and to seal out water is to use a product called SPARTITE™.
This product gets poured into the space between the mast and partners and hardens to form a
reusable hard rubber chock around the mast.
Now, using a halyard or a steel tape measure suspended from the masthead, check to see that it is
centered by measuring to the same spot on either side of the boat. (Be sure that the halyard or tape
measure is led clear.) Next, tension the upper shrouds. They should be as tight as you can make
them with a pair of wrenches. Never use an extended piece of pipe on the handle of a wrench
because you will over tighten the rigging and do damage to the turnbuckle.
Work down the mast (upper intermediates, lowers, etc.), sighting up the mast for straightness.
Relatively speaking, the cap shrouds should be tighter than the intermediates because they are longer
and will stretch more under load.
Now you can tackle fore-and-aft tune. Tighten the backstay to the maximum tension you will use
while racing. At this point you should have the maximum amount of mast bend for your boat. If you
don’t have enough bend you can ease the headstay or move the mast either forward at the partners or
aft at the step. (To check fore-and-aft bend, attach the main halyard to the gooseneck and pull it
tight. Mast bend is the maximum distance between the halyard and the mast. See diagram).
Now it’s time to go sailing. Put the boat hard on the wind in at least 10 knots of wind. It’s a good
idea to have enough crew to handle the boat easily. Use a non-overlapping genoa so that tacking is
quick and easy, you'll be tacking a lot while tuning.
Before you start tightening the shrouds, take a look at your mainsail. If you feel the main is not
flat enough, you might need more mast bend. Even though you made the shrouds tight during your
dock tuning, they may be loose on the leeward side when sailing. Your goal is to get the mast
straight and to have the leeward shrouds straight, not dangling, when the boat is hard on the wind in
15 knots of breeze. If the leeward shrouds are loose when the boat heels, tighten them to remove
about half the slack. Keep track of the number of turns you make. Next, tack and make the same
number of turns on the other side. Do this back and forth tuning until you are happy with the tension
and the leeward side does not move around when the boat heels.
When you are done, sight up the mast to make sure it's still straight. If not, decide what
adjustments are needed; tack the boat and make them. Sight up the mast on the new tack and once
again, decide what adjustments are necessary. Tack again; make the adjustments and check how
well your previous changes worked. Keep repeating this process until the mast is straight on both
tacks. If you have a problem, contact a professional rigger.
BEFORE UNSTEPPING YOUR MAST, MAKE SURE TO PUT TAPE MARKS ON YOUR
TURNBUCKLES SO THAT YOU CAN RETURN TO YOUR CURRENT RIG SETTINGS
WITHOUT HAVING TO GO THROUGH ALL THE TACKING AND TUNING, TACKING AND
TUNING AGAIN.
TUNING FOR PERFORMANCE
Your boat’s performance can be improved with careful tuning. First, think critically about your
helm balance. If you are carrying more helm than you’d like, try sailing with less rake. Conversely,
if you’d like more “bite” in the helm (weather helm) rake the mast back another six inches to a foot.
For the best feel when steering upwind, the boat must want to head up toward the wind. Set the mast
so that the rudder must be turned three to five degrees to keep the boat going straight.
If you want to get optimum performance out of your sails, good tuning is a must. If you have the
controls available for tuning underway, you can adjust to changing conditions. If you don’t, then set
up for average conditions. Jib draft can be controlled with headstay sag; more sag, more draft; less
sag, less draft.
Mainsail draft can be controlled with mast bend; more bend, less draft; less bend, more draft.
On a masthead boat, the permanent backstay directly controls headstay sag and also affects the
amount of mast bend.
On fractional-rigged boats, the permanent backstay controls mast bend only. Unless the
fractional-rigged boat is equipped with running backstays, headstay control is difficult to achieve.
Runners on masthead boats, check stays on fractionally-rigged boats, and babystays all control mast
bend. Mast bend can also be induced (as mentioned earlier) by moving the step aft and/or moving
the mast partners forward.
TUNING NOTES
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If your leeward rigging hangs too loose, it can mean that your starting upper shroud tension
was too low.
Set up your rigging so that you can get a firm headstay when the breeze is on, it will make
your boat go faster.
Check your mast in rough sea conditions. If it is “pumping,” meaning the middle of the mast
is moving fore-and-aft, tighten your running backstay or babystay.
Use brass cotter pins. They are much easier to bend so that you can get them in and out in an
emergency.
Don’t forget to tape over your cotter pins and any other rough spots.
Bend cotter pins over completely. A half-bent pin can poke through tape and murder a sail.
Check your tuning frequently — all rigging has some stretch, which can throw tuning off.
Care and Protection of Sails
As sailmakers, we are acutely aware of the cost of sails as part of the total investment in owning
and operating a sailboat. Experience has also shown us that the treatment of new sails after they are
delivered can greatly extend or shorten their useful life.
Naturally, one of the main determinants of a sail’s life span is the quality of the materials used
and the workmanship of the sailmaker. High-quality custom sails like those produced by UK
Sailmakers will generally last a good deal longer than sails made by production sailmakers —
American or foreign. Regarding proper treatment of sails to promote a long useful life, there are
many steps that can and should be taken. We have divided these into three main areas:
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Preparation of the boat and rig.
Proper treatment of the sails on board.
Care and maintenance.
In each area we have a list of suggestions or recommendations that you may want to use as a check
list.
PREPARATION OF BOAT AND RIG
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Tape all cotter pins, sharp corners and other points that can tear or chafe sails. Give particular
atten-tion to the pulpit area. Make sure you tape off the turnbuckles where the lifelines
attach.
Place boots or tubes over turnbuckles, both to prevent chafe and to keep grease and oil off
sails.
Be sure the lifelines are clean and free of meathooks. Give particular attention to the
stanchion tops. Acetone is a good cleaner for vinyl-coated lifelines.
Install rollers or padded boots on spreader tips.
Be sure wire halyards have no meat hooks or open wire on the shackles which might chafe or
snag the sails.
Position guards to close off any “V’s” in the rigging that may catch the sails when they are
being hoisted or lowered.
Wash the deck before each weekend of sailing, and polish the spars periodically so that sails
don’t pick up any of the aluminum oxidation.
Dry out your sails before leaving them on the boat for any period of time. One way of doing
this is to simply spread the sails around the main cabin and forepeak so that the air can
circulate and dry them between outings.
Avoid the practice of drying sails by hoisting them to flog in the breeze.
Finally, minimize exposure to direct sunlight when drying your sails.
PROPER TREATMENT OF SAILS
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Be sure the hardware on your boat is entirely compat-ible with your sails. For example: The
clew of the mainsail should not ride above the boom so high that an excessive load is put on
the last slide or the bolt rope.
Don't use your sails in excessive wind. Check with your UK Sailmaker for the wind-range
appropriate to your particular sails.
Don't luff or flog your sails unnecessarily, or motor with your sails up.
Shorten sail as soon as conditions demand it. Don't luff your mainsail when a reef is needed.
Don't carry a jib that is overburdening the boat — change down to a smaller jib.
Don't allow running backstays or unused halyards to slap against the sails. Be sure running
backstays have all their cotter pins and sharp edges taped or covered in leather.
Don't over hoist sails. A vertical wrinkle along the luff while sailing is a good indication that
too much tension has been applied. You should normally use just enough luff tension to
eliminate horizontal wrinkles in the sail.
The same thing applies to the main outhaul. Tighten the outhaul only enough to eliminate
vertical wrinkles in the sail.
Don't over-tighten leech cords. Tighten them just enough to remove the leech flutter, and
note that as the sail is trimmed harder, the leech cord should be eased.
It is critical that headsail sheet fairleads be located in the proper fore and aft position in order
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to avoid straining either the leech or the foot of the sail.
With overlapping headsails, it is possible to trim the sails so hard that they come into contact
with the spreader tip. This should be watched carefully, particularly on a puffy day. If you
sheet the sail to one inch off the top spreader in heavy air, and the wind dies, the sail will
push up against the spreader tip. Therefore, have the trimmer play the sheet in puffy
conditions.
When tacking, be sure to cast off the leeward sheet early enough to keep the leech from
hanging up on the spreader during the tack.
Never use laminate sails (Mylar or Mylar/Kevlar) without first applying both spreader and
stanchion patches as supplied by your sailmaker.
Before furling or flaking the main, ease the outhaul so that the foot of the sail is not under
tension — there is no need to stretch it out. If you have a roller furling jib, ease the halyard at
the end of the day to prevent the luff from stretching out of shape.
After sailing, be sure to cover the mainsail if it is left on the boom. Similarly, if you have a
roller furling headsail, make ure is rolled up with the UV cover on the outside of the roll.
SAIL REPAIR
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If you do tear or otherwise damage one of your sails while you are using it, here are a couple
of pointers.
Get the sail down as quickly as you can in order to minimize damage.
If possible, don't use the sail again until you have it repaired by a professional.
Small tears, cuts, pinholes, etc., are generally not anything to worry about and shouldn't
prevent you from using the sail.
The best temporary cure for minor damage is tape. Sticky-back insignia cloth, duct tape, or
even adhesive tape from your first aid kit will work. The stickier the tape, the better! Try to
rinse the area with fresh water and dry it first. Then tape both sides of the sail. Acetone can
be used to help dry the sail if nothing else works. Simply apply the acetone to the spot you
want to fix and wait until it evaporates.
In an emergency, you can sew up your dacron sails with a needle and thread. If reinforcing
material is needed, use one or more of your sail stops. They are very strong yet easy to sew.
On the other hand, we do not recommend trying to hand-sew laminate sails. The stitch holes
made by a sailmaker's needle often does more harm than good.
CARE AND MAINTENANCE
Sails that have been used frequently, or in heavy weather, should be washed at the end of each
season, preferably by your local sailmaker. If that's not possible, soak the sails in a warm soap
solution for a couple of hours, then hose them off thoroughly. Make sure they are completely dry
before folding. If the sails are particularly dirty, add a small amount of bleach to the water before
soaking. Dirty spots can be lightly scrubbed. Laminate sails should be hosed off, dried and folded.
Try not to soak or scrub them.
STAIN REMOVAL
Blood and Mildew: Soak the stained area in a mild bleach solution for two hours; scrub lightly.
Rust: Rust removers are offered under many commercial names and are available at just about any
hardware store. Just make sure you rinse the cleaned area thoroughly.
Oil, Grease, and Tar: Dab the stained area with acetone or lighter fluid and then rub the stain with
clean rags. Once the stain is lightened, scrub the area with a detergent and water solution. Rinse all
the acetone out of the material.
STORAGE
All sails should be folded or rolled in a manner that avoids sharp creases. Sails should be stored
under well-ventilated, clean conditions. Damp-ness, which may encourage mildew, should be
avoided. While mildew growth does not affect the strength of these sails, it can cause unsightly
stains that are not easily removed.
BACK TO THE LOFT
It is very important to the life and strength of your sails that you return them to your sailmaker's
loft once a year for checking, refurbishing, and washing. This practice can add years to the life of
your sails and help you to get the most out of them in terms of speed and appearance. We cannot
emphasize this point too strongly. GOOD LUCK AND GOOD SAILING!
Applying Spreader Patches
Chapter 1
Chapter 2
Chapter 3
Chapter 4
Chapter 5
Chapter 6
Chapter 7
Chapter 8
Chapter 9
Sail Care
Applying Spreader Patches
Chapter 10
All new Mylar-based genoas either come with spreader patches in
place or with spreader patch material to be applied. The patches are
sticky-back Dacron material that protect the sail from wear as the sail
scrapes across the ends of the spreaders during a tack. Never use a
genoa in a race without the patches in place.
To determine the proper location for the patches, put the genoa up in
calm conditions and go up the mast in a bosun’s chair to mark where the
spreader hits the leech when the sail is sheeted in tightly. The patch
should span from eight inches in front of that point all the way back to
the leech.
Since the leech of the sail rises up when the sheet is
eased, place the patch so that three-quarters of the patch is
below the point where the spreader hits the sail when
sheeted in. Don’t forget to put patches on both sides of the
genoa.
Before you lower the sail, don't forget to mark where
the stanchion patches should be. Also mark where the foot
touches the shroud bases so that you can put protective
patches there too.
If you do poke the spreader through the sail, bring the
sail in for repair and ask the loft to patch the tear with two
plys of material under the Dacron sticky-back.
To put the patches on a genoa, make sure that the sail is dry
and salt free. With a large flat surface to work on, crease the
first five inches of leech edge of the patch and peel off the
backing paper. Tack that edge in place so that the patch will be
parallel to the water and that two or three inches of the patch
extend off the leech of the sail. Lay the patch flat against the
sail and have another person slowly peel the paper out from
under the patch as you smooth it to the sail, avoiding air
bubbles or folds in the material.
Hint: The two people doing the job should use their knees to
keep the sail under tension so that the sail stays flat in the area
you are working.
Next, return to the leech and fold over the first few inches of
material that you left loose. After the patch is in place, use a
hard plastic squeegee,wooden wallpaper roller or blunt side of a
pair of scissors to truly press the patch to the sail.
Repeat the same process on the opposite side of the sail.
Glossary
Afterguy: The spinnaker sheet that goes through the jaw of the spinnaker pole. Big boats usually
attach a separate sheet and afterguy to both spinnaker clews. Since the afterguy takes more pressure
than the sheet, the afterguy is a heavier line. Most of the time afterguys are simply called “guys,” not
to be confused with the “foreguy” (see next page).
Aspect Ratio: The height of a foil like a sail, keel, or rudder divided by its width. A high aspect sail
has a long luff and short foot.
Bias Elongation: See Warp.
Bi-Radial: A sail construction technique where radial panels emanate from the head and clew. (See
tri-radial.)
Boomvang: A block-and-tackle or hydraulic ram that controls the angle of the boom. Lowering the
boom tightens the leech of the mainsail.
Clew: The back corner of a sail. On a mainsail the outhaul is attached to the clew; on genoas, the
sheets are attached to the clew.
Crosscut: A sail construction technique where all the panels are parallel to each other and
perpendicular to the sail’s leech.
Cunningham: A control that adjusts the position of the draft in a sail by changing the tension on a
sail's luff. The control is named after its inventor, Briggs Cunningham.
Draft: 1. The deepest part of the curve in a sail. 2. The distance from the water line to the bottom of a
boat’s keel.
E: The designation for the distance from the aft face of the mast to the outermost point on the boom
to which the mainsail is pulled.
Fill Threads: See Warp.
Flattening Reef: A sail control that flattens the bottom part of the mainsail. It’s called a reef because
the control line passes through a grommet on the leech of the sail about a foot above the boom.
When the line is tightened, the grommet is pulled down to the boom and out as far as the sail can
stretch. Also called “flattener”.
Foot: The bottom edge of a sail.
Foreguy: The line that pulls the outboard end of the spinnaker pole down — not to be confused with
the “afterguy.”
Foretriangle: The triangle formed by the forestay, forward edge of mast and foredeck.
Gooseneck: The mechanical joint that connects the boom to the mast
Halyard: A line used to hoist or lower a sail.
Head: The top corner of a sail
Headstay Sag: The deflection of the headstay to leeward and aft caused by the force of wind on the
sail. Because of the physics, no matter how tight your rigging, there will always be some sag in the
headstay. I: The designation for the measurement of the height of foretriangle. Each rating rule has
slightly different places which to measure from. J: The designation for the measurement of the base
of the foretriangle, e.g., the distance between the mast and the forestay
Jib Lead: The block or fairlead, through which the jib sheet passes, between the clew of the jib and
the winch. The position of the lead has a great effect on the shape of the jib
Laminated Sail Cloth: A fabric that has multiple (at least two) layers of fiber and film that have been
permanently bonded by adhesive. The film provides the structure to control bias stretch. The fiber, in
the form of woven material or unwoven yarn, provides stretch resistance in the fabric’s oriented
direction. Also see “Scrim Cloth”.
Lazy Guy/Lazy Sheet: Lines used on big boats for jibing the spinnaker. Each clew of the spinnaker
has a guy and sheet attached, the ones not in use are called the lazy guy and lazy sheet.
Lee Helm or Leeward Helm: The tendency of a boat to bear off when the helm is released. Lee helm
is nor-mally encountered in light air or if your mast is too far forward in the boat. See “Weather
Helm.”
Leech: The back edge of a sail.
LP: The abbreviation for Luff Perpendicular, which designates the shortest distance from the clew to
the luff of a genoa. The size of genoas is expressed in a 54 percentage, which is the LP divided by J.
For example, if a boat’s J measurement is 12 feet, a 150% genoa will have an LP of 18 feet.
Luff: 1. The forward edge of a sail. 2. The flapping of a sail caused by the boat heading too close to
the wind or because the sail is not trimmed tight enough. 3. “Luffing” is altering your course toward
the wind. In racing, luffing is a defense permitting a leeward boat to protect its wind from a boat
passing to windward
Outhaul: The control line that pulls the mainsail clew to the end of the boom, tightening the foot of
the sail.
Overpowered/Underpowered: A boat is overpow-ered when it heels too much from having too much
sail up. Underpowered is when a boat is slowed because it does not have enough sail up. P: The
designation for the measurement from the top of the boom at the gooseneck to the highest point on
the mast that the mainsail will be raised.
Rake: The mast's inclination from vertical. The amount of rake is measured from the back of the
mast at the partners to a plumb line hanging from the main halyard.
Reacher: A high-clewed genoa used when reaching in heavy winds. Also know as a "blast reacher."
Roach: The area of a mainsail that protrudes beyond a straight line from the head to the clew. The
roach is supported by battens.
Scrim Cloth: An extremely loosely woven cloth. Lami-nated to Mylar, scrims make strong,
lightweight sail cloths. Scrims are distinctive since there is empty space between threads.
Shelf Foot: An option for mainsails that gives extra control to shaping the lower third of the
mainsail. The name comes from the flat piece of cloth that connects the bottom of the sail to the
boom.
Shroud: Wires that support the mast athwartships.
Spreader: Strut attached to the side of the mast, which amplifies the shrouds ability to support the
mast.
Squaring the Pole: Tightening the afterguy, which pulls the spinnaker pole back.
Stay: Wires that support the mast fore-and-aft, e.g.,"forestay" and "backstay." Also see “Shroud.”
Tack: 1. The lower forward corner of a sail. 2. Turning the boat so that the bow passes through the
eye of the wind. 3. (Port or Starboard) You are sailing on starboard tack when the boom is on the
port side and vice versa.
Tape-Drive ® : The patented sail construction system used by UK Sailmakers, which uses high
strength Kevlar tapes to lock in a sail’s designed shape. The tapes radiate from the three corners of
the sail along computer-mapped load lines.
Telltales: Streamers attached to the sail to indicate wind flow. Tri-Radial: A sail construction
technique where radial panels emanate from all three corners of the sail. (Also see bi-radial.)
Warp, Fill and Bias: Woven cloth has threads running in two directions. Fill threads run
perpendicular to the longest side of the cloth and warp threads are parallel to the longest edge of the
cloth. The strength of woven cloth lies only in the direction of the threads. Stresses not parallel to the
threads are called bias stresses. The farther off the thread line the stresses are, the greater the
distortion of the cloth. Bias stresses at 45 degrees to the threads distort the sail the most.
Warp-Oriented Cloth: Sail cloth that has more strength in the warp direction than in the fill direction.
Extra strength is created by more or stronger threads run-ning in the warp direction. Some extreme
warp-oriented laminates have no fill yarns. Instead, yarns are just glued to the Mylar film in the warp
direction. These extreme warp-oriented fabrics rely on the Mylar for strength in all other directions.
eather or Windward Helm: The tendency of a boat to head up when the helm is released. Weather
helm is measured in degrees of angle that the rudder must be turned to sail a straight course. See
“Leeward Helm.”