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Last update February 13, 2004

 

Regatta Sailing Basics, February 2004

 

Fleet Racing a Fleet Race, July 2002

 

Considerations and the Rules, June 2002

 

Dummy Reflections, January 2001

 

Dummy Reflections

 

The Skipper

 

        The Boat                     Tuning                     Boat Handling

 

       Race Plan                     Tactics                     Fleet Etiquette

 

        Hangar Flying            Final Thoughts About The Summer

 

Page One of Three

Page 2     Page 3

 

Reflections by a Dummy... by Rick West, January 2001

 

This section is pointed at the new sailors or those who would like to go out where the big boys play. The above subjects will be linked as soon as they are completed.

 

The subject matter is from those thoughts regarding the summer of 2000 and my introduction to racing the EC12 in large fleets. While one may be the top dog in their small pond, here you gather with the top dogs from a lot of ponds. However, this does not make up the entire fleet as at each event there are those that have never been to a major regatta or sailed outside their club environs.

 

Large fleet regattas have heat racing. As opposed to full-scale sailboat racing, we have the opportunity to observe the action while alternately being involved. You can watch the tactics and conduct of one individual or the interaction of several with each other over the course of a heat. It is a wonderful time to meet others and talk about their approach to areas were you have questions. Those involved will share and if you are into racing and the finer points of sailing this is the candy store.

 

On the EC12 homepage, you will find a schedule of two-day events, mostly on the East Coast. During the Lake Norman regatta in North Carolina, the three East Coast regional representatives work out the schedule for the following year to avoid major conflicts. There is an event monthly somewhere in these regions that sailors travel great distances to enter. Entries generally are in the twenties but some, like Elon College, into the thirties. In 2001, they are expecting forty boats at Charleston! I went to four of these, and the nationals, and had a wonderful time. The racing was invigorating while the friendships were warm and the camaraderie comforting.

 

What are my qualifications for this series? None! I do it because I can and have bought the space. Like the theme throughout this website, it is to share what we have learned when the nearest EC12 to Delta MYC is 800 miles away. We started out on a different and lonely planet. Now, we are part of a bustling star system.

Enjoy. I hope it is helpful.

 

The Skipper

 

We all want to have a fast boat. That is natural and it certainly doesn't hurt. But the fact is that what is considered to be a fast boat, and one thought to be a slow boat, when tuned and captained by one competent sailor, the difference can be very little.

 

Recently (2000), Kelly Martin, the dominate competitive EC12 sailor in the last dozen years, commented in the Seattle Waterlines that performance was 80% skipper and 20% boat and luck. Here is an actual example to support that statement. It does not speak to the percentages but certainly weights the skipper.

 

The competitive sailing order at our club has been the same in the final results at the end of the season. One Saturday in 1999, five of us gathered but only four boats were available. In order for everyone to get in some sailing, we tried this:

 

The winner of each race would sit out the next race. The last place skipper would take the helm of the first place boat. The skipper that had sat out the race would enter at the helm of the last place boat. The guys in second and third would swap boats.

We followed this rotation for about four hours. The final point count was the same sailing order generally posted. While we had not done this as a deliberate test, the result was illuminating. We now call this individual point racing. It is likened to that in Bridge and Doubles tennis where individual scores are tallied though rotating partners.

Another example was my first visit east at Columbia, Maryland. By prior arrangements, I would sail Mark Rinehart's 1260 while he assisted the RD with the regatta. Mark is certainly one of the top five sailors in the country if not higher. I finished at the bottom of the fleet. I can assure you it was not the boat.

 

You can easily go through the boat in short order. Dealing with yourself takes considerably longer. Enough said?

 

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The Boat

 

Two of us spent several months in 1999 going over the Optimizing Manual. It is hard to read for the layman in the scientific and engineering process. Most of us do not have the education and math to reach these levels. But what we can do is study the material and in time you begin to make some sense as to the goal of the effort. By repeated reading of the various subjects, even dummies like me start to see the light. You do not need to know how to set up and conduct a Lamboley test to know what considerations you will have in planning a new boat.

 

The Manual goes beyond this test and into some things that are more easily understood. A lot of it is interesting with good common sense value. What I hope to do here is get some of this meat off the bone so that it is more easily digested; to show you why a path was taken during construction.

 

Before construction started in 1999, it was known that the guy at the helm was the key. But if you could make the boat the best it could be, maybe there would be a slight edge to offset our personal performance. I am sure, in my travels, that others are impressed with 1494 and wonder if I will ever measure up to the boat. Starting to get the picture?

 

Weight

Aerodynamics                    Trim                    Hull Fairness

 

Weight

The total weight of the boat and where it is located should be one of the major considerations in the construction plan. We cut through all the worry and bought the commercially available keel ballast for the 95 standard hull. Yes, we knew of long and short pours and that some hull manufacturers poured their own lead. There was no way in Hell we were going to do that. At the time it seemed to make since buying one that was designed by those who did the testing for the Manual.

 

Multiple ballasting made a lot of since too. It only stands to reason that a lighter boat will accelerate faster than a heavier one. We all have the same size sails. Likewise, a heavier boat will stand taller in a breeze than a lighter one. Multiple ballasting gives you a little of both. 

 

Listening to Bob Sterne's tuning tape, I learned that an EC12 sails best with 30 to 35 degrees of heel. So, based on the wind conditions, I will choose one of four total boat weights that will give me that heel. (You can see those weights on the Final Weigh-In page.) You can learn this by testing and making notes in a tuning booklet. If you are not familiar with the concept, it goes like this:

 

The relationship to heel is wind strength versus total boat weight and where it is located. There are other factors but this is the heart of it. The more total boat weight (down low) that you have the more stiff the boat will be. It will tend to sail more upright in a given wind than one with less weight. The one with less weight is said to be tender and will heel more than the other. So, as the wind increases, you add weight seeking that optimum heel angle.

 

That is the concept. Example: The wind is light and variable. You have ballasted for your lightest weight. Your competition is heavier. You will heel more in what wind you do find and you will sail faster than the heavier boat. You will accelerate faster out of a tack, on a wind puff or a shift than the heavier boat. The differences will be small but if you do everything right, in theory, you will beat the heavier boat.

The catch to all this is that you must make a decision on weight at the beginning of an event. The rules require that you maintain that weight throughout the same event.

 

So, what is your building challenge? With 19 pounds of lead sitting on the table, you need to build a boat (complete with everything...ready for the water) at around 5.5 pounds. Why? Because your competition is going to be at around 24.5 pounds...you can bet your bippy on it.

 

How did that weight come about? Because, the class requires that we have a waterline between 42 and 43 inches. Therefore, a boat built to the beam specifications (at the correct stations) will be flirting with the maximum waterline at that weight. Trust me, it will!

 

Likewise, if you build heavily with 19 pounds of lead in the boat you will exceed the waterline restriction. Now weight needs to come out of the boat and what does that do? It makes you more tender while the other guy is stiff. Now, "You know what I mean, Vern?"

 

I have to tell you that I have discovered in my travels that few multiple ballast. I also learned that few know the weight of their boat. "Hey Vern, come here..."

 

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Aerodynamics

 

Aerodynamic drag is a consideration in full scale competition sail boats and they have a way of measuring it. If they deal with it so should we. If I am standing on the prow with my arms spread out screaming, "I'm king of the world," I am slowing down the Titanic. Albeit, very small but I am part of the equation.

 

The first of the EC12 manuals treats with it more so than the second. Here you will see examples of a more clean way to rig. The effort is to eliminate, or at least greatly reduce, large items on the mast, booms and in the rigging. Move all the controls to the booms, use smaller spreaders and thinner jumper struts. Use an internal shroud wire termination rather than a tang screwed to the mast. Use an internal mount for the forestay and the jumper wires. Second best is a very small eye screw glued into the mast not a tang that is flat to the apparent wind. Use the Sullivan or DuBro clevis connectors with a rigging coupler rather than the larger turnbuckles. ( I take issue with the Manuals on this.)

 

Move the antenna inside the hull and away from the battery and electrical wires. Eliminate a deck power switch and go back to the radio board. Make sure the shroud racks are parallel to the centerline of the boat and reasonably away from water over the gunwales. Look at any fitting and connector and say to yourself, "Can I make this smaller, flatter, lighter."

 

Consider taking the time to craft your own fittings for your sail controls. Those described in the first manual are of nickel-silver wire and a pain in the Bippy to fashion. But once learned, all controls will fit on the booms, can be adjusted with one hand and are clean to the apparent wind. Use the Bowline knot where you can. It is smaller, stronger and does not slip. On the topping lift tension safety use small elastic thread, found in fabric stores, and aluminum crimping sleeves for the loops. Mount this along side the jib boom for a clean profile.

 

Stand back and look at the deck and rig. Think about it. Do what you can and you will come to admire a clean rig. You will come to feel pride in your efforts. It will make you feel more confident on the water...it will!

 

What will this gain for you on the water? Generally, not a lot. But you will know you made an effort and hence, better prepared yourself for being on the water. That is a biggy. My personal observations have been that when the wind blows the fleet gets closer together. But in light air they spread out and seamanship starts to show. I have also noticed that the guys up front generally have the cleaner boats. In light air, little things mean a lot. A boat length over your competitor is huge.

 

Do I see aerodynamic drag considerations in my travels? Very little. Mostly, they go for convenience and accessibility.

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Hull Fairness

 

The hull has drag but not like that of the rigging. It comes from a hull that is not smooth, eddies caused by the rudder, rudder alignment, paint lines, decals and pond scum. Thinking about it will produce more. They add up and you can deal with it.

 Rod Carr developed a visual aid to check the fairness of hulls. There is a description and discussion in the Optimizing Manual page 70. The device shows uneven sections of the hull. In time, this will surface for a number of reasons. I have not heard mention of the device in my travels but sanding is talked about. Most run their fingers over the hull to feel areas that need sanding. However it is done, it is a conscious consideration in preparations for major events. When one mentions 1500 grit to me I know they are serious in their effort.

 With age, a certain lack of fairness will occur from the cradle, handling in and out of the water or just temperature cycles. Such an optical device has not been tested here, as our 95 standards are not a year old yet. We have excellent boats for testing with the Dumas EC12s though. They never had a keel supported cradle till now. I am sure they are a disaster.

You may have read, during the previous building period, that we attach no wood to the hull forward of the rudder. This restriction is to prevent any internal pressures on the hull developing over time. Such pressure will effect the outer hull surface. That is why, in the current construction of the swing arm boats, the radio platform mounts are glued to the ballast.

 A rudder fairing is a must. Our fairings are sanded to accept 37 to 40 degrees of deflection. We consider this deflection all that is needed downwind. Beyond this the leading edge of the rudder enters the slipstream creating additional drag to the deflection itself. The bottom of the rudder should be set in the sleeve so as to be a continuation of the keel line.

 We use the Rinehart Rudder which, is growing in popularity back east and is now made for other hull manufacturers than Brawner. I understand that there are some differences in the rudder fairing treatment among the 95 standard manufacturers. The top leading edge of the rudder needed to be rounded to fit the Ribeiro hull. Mark knows all the hulls and can advise you if some sanding is needed. This rudder is thinner than some I have seen hence, we have not sanded down the center of the barndoor. Whereas, this technique has been used to draw the water down to the rudder surface, the Rinehart rudder lies nicely within the fairing plane. Short of a wind tunnel test I would say there are little or no eddies.

 The rudder on my boat has a null area created by looseness in the ball linkage. This type linkage was needed to meet the angles from the low servo to the high tiller. I do not know the negative effects that any chatter might create. I have not discussed it with others as an oversight. I just don’t like it. I am considering a push/pull stranded wire connection to four clevis connectors. Are there any comments on this?

 

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Trim

 

The blueprint I have of a structured and balsa covered deck boat came from the East Coast and indicates a setup for one-degree bow up. Indeed, most of the boats I have seen there certainly have the profile for this trim angle. In the Northwest the general profile is a lower bow. Opinions on the subject were all over the auditorium among those that would comment at all. This was disappointing. I was hoping for something to backup or shoot down my conclusions. I didn’t even learn anything new. Well, not so! I experienced and observed. While I am challenged in the scientific process, I doubt to stimulate thought. So, this is what you get…me. There are some opinions out there but I don’t think anyone really knows. 

Just in fantasy I have put together some scenarios of different groupings of sailors with various profile trim angles. I won’t bore you with them but I can predict with a reasonable degree of accuracy who will come out on top in the end. It was a wonderful mental exercise that proved nothing. Anytime I plugged Kelly Martin into the exercise he won. It is fun to speculate and banter conclusions based on this but if you thought he won because he sails with a low trim angle, I will try to sell you some acreage in Honduras. 

Seriously, I have to go along with the reporting in Chapter 2 of Optimizing as a guide to opinion. I also have to add my flying experience as well. My gut feeling is to sail the boat on “its lines.” There has to be naval architectural reasons for the keel line of the EC12. Sail on that line in as many conditions as possible when racing. 

International airline transports have flight management programs for flight management systems that control the aircraft through multiple computers. This process has control over speed, center of gravity and trim and will update the inputs constantly as the aircraft becomes lighter and from sensors on the environment; to simplify the process. The most efficient angle of attack of the aircraft has already been determined through design and is part of the programming. The best analogy I can present as to this process is that the system is trying to balance the aircraft on a pencil. That will produce the most efficient platform for the aircraft within the requirements requested. When you read about full-scale sailing and references to the “bubble,” this is it in transport aircraft. There are a lot of considerations regarding angle of attack in aircraft but as it relates to our EC12, it is trim angle. So, what begs the questions is what angle of attack is the most efficient for the EC12. Until proven differently I will go with the keel line. 

If you were to sail an EC12 at a higher angle of attack than the keel line is at rest, you will be presenting a profile where the oncoming water is more in contact with the hull more than it would be at rest. This is fact! If the need to sail fast is a higher trim angle, then the rudder will be smaller because the rear of the keel area would be closer to the gunwale. Think about it. That would be a different line. Conclusion: when there is a higher profile presented before the movement through an environment, there is more drag to that movement. Makes sense to me. 

Most of you that sail EC12s have been through this drill. You have also probably noticed the bow angle lowers as the wind comes up. For those of you that are new to this…trust me. This is what sailors do and this is what you will see. 

You understand that it is the driving force of the sails that moves the boat forward? The sails actually pull the boat forward and they are above the waterline. Right? Ok, now don’t touch anything. As the wind velocity increases the pulling force increases and because it is above the waterline it forces the bow down. As the bow lowers the mast tilts more forward and therefore, the entire sail plan moves forward. At the same time the sails are trying to plane into the wind, decreasing the angle of attack. The force is now forward and trying to move toward the eye of the wind. 

I don’t mean to offend your intelligence. This is the process I use toward a mental conclusion. Keeping it simple helps me stay focused. 

Within the sail plan is a center point for this force. It is called Center of Effort or CE. So, we can simplify the understanding by saying that as the wind increases the CE moves forward and the boat heads up into the wind. As a skipper, on the water, you start hauling in on the rudder. This is called weather helm. To help, you will also let out the booms (sheeting out) to reduce the angle of attack. Both actions slow you down but you have better control. 

The boat is said to be out of balance. There is an area on the deck of your boat where the mast will sit and the boat will be in balance. It is different with each boat, but close, and depends on what rig you have up and the wind velocity. Oh yes, there are more factors that will be addressed later but I am trying to get to TRIM in a simple way. I have spent the whole summer looking for mine. I am closing in on it. At the nationals one evening I moved the mast step a half inch forward. This is not a good place to make such a change but it had to be done. The boat was out of balance. The next day I placed fourth in points for that day. I finished 12th overall but learned a huge lesson in balance and Center of Effort. 

Getting back to the scenario above. As the conditions drive the CE forward, you move the rig forward. You move it till you are in balance; till the weather helm is nil to light and the sheets are close hauled. You will point higher with less rudder drag. You will go faster. You won’t have to fight for control of the boat. If the wind slackens, you will go the other way, right? 

Okay, good! But what have you done about the trim? Somewhere in the wind conditions and various CE positions (mast step holes) the boat will be in balance and in trim. If you have no means of adjusting the trim angle, or the weight, there will be only one place for each hole on a certain day. On that day you will be fast and wonder about the other days. What if you had four or five places for each hole? 

Multiple ballasting not only gives you the ability to change the boat’s total weight, inertia through the water and the righting moment, it allows you to change the trim angle. So, where is the baseline? 

I started at the lightest allowed weight to be at, or as close as possible, the 42 inch waterline. I would use this weight for light and drifting conditions on the water. My mast will be aft to get the CE aft to allow the boat to come up and point into whatever air it can find. In the tank I am looking for zero to .1 degree positive. If you do not have a tank take a good look in the water. Is it on its lines? In these conditions there should not be enough wind to push that bow down noticeably. 

Then at the heaviest weight, close to the 43-inch waterline, I am looking for about a one-degree positive trim. This will be used on the A rig at the upper limit, probably around 7 or 8 knots. I should see the boat sailing on its lines not one-degree up. Wow!

In between these points are where combinations of Big and Little Foot come in that you have seen here on the website. Optimizing did the scientific approach and the numbers have been observed before I came along. I didn’t invent them. I have just tried to break in down where I thought it understandable. 

One more thing to clutter this mess. Having thought this though and thinking it to be a good thing, I went further during construction. I took a section off the bow of the keel ballast and called it Baby Foot. This small section will always be in the boat but I could use it to increase the already documented trim angle when needed. The condition would be in light or moderate wind and the water is lumpy or rough. Sailors have stated that in such waters you want the bow higher to move through the impact of this water better. It makes sense to me. When it gets rough in airplanes, we slow down increasing the angle of attack. 

I know it was long but that is my story and still not understanding what I do know. It just makes sense to me. I hope it does for you. Do you keep a little notebook?

 

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Tuning

 

Let's get something straight on the outset. I am not a master tuner and like most things in RC sailing, I do not know what I know. Just trying to write this section is probably an absurdity. But I will try to relate what I have picked up along the way through osmosis and observations and talking to others. I have been to New England, New Jersey, the Southeast, the Northwest and the Heartland of this country in the last six months. I won't say, "I have seen the light," but there is a common thread of understanding.

 

It was very interesting to observe the differences between our little planet and the solar system back east. We seemed to have looser sails and more main boom offset to the centerline of the boat. Our main and jib had more camber with the draft further back and we do not run the main boom in tight at closed hauled. It is hard to know where you are when sailing with five guys that all do the same thing. I mean, we are a real family. Then I go into Liberty Bell and got luffed on the first beat. It was so bad I had to tack. Then I was distracted the rest of the race having discovered I was not even close to being able to point with these guys. I corrected that in a hurry.

 

So, through the course of the summer the main came into the realm of sheet vanging and steadily became more flat. The jib was adjusted out more with just a little more camber than the main. In the conditions I found the mast started moving forward on the deck until at Stowe the mast step had to be reset so I could get another 3/8” more forward. Finally, on the last day, the boat was in balance. The boat had been in the water for three months. I am a bit slow on some things but in this case I was stubborn.

 

It should be noted that everywhere I went the wind was light and sometimes nil. Everyone complained about how unusual it was. Other than the action with our small group here, I have not experienced large fleet racing in a breeze. It was interesting to note the different tuning concerns among those with sails from different sail makers. Each had their own characteristics which lend to a tuning process. All were different to the CarrSails we use here. But in listening and asking questions I began to fill in some of the gaps in my understanding from many areas of reading. This will be the basics for high twist sails.

 

My reading, so far, has been anything I can find on the Net from club sites and to include Stewart Walker’s book, Speed and Smarts by Dellenbough and the North Sails Fast Course. These were to learn the dynamics of a sail and the shape effect of control inputs. These basics were then overlaid with light, medium and heavy air. Blending this together will bring some understanding why you want to make changes for the existing sail environment. If you are excited about sailboats this reading is recommended. Walker’s book is hard. It is like a junior year lecture and it is time to be assimilated. But remember, you do not have to understand all that you read to make some sense of a little of it on the water. That little bit will fuel your curiosity so you may return to the book. The books were important here because we couldn’t go across town to Vern’s for his answers. I suggest you read, then ask, then go to the water and then ask again. A lot was learned this summer from many willing to take the time to share their thoughts. And, as always, there is time in between to reflect. During this time watch Bob Sterne’s video. I will again this winter.

 

If you do not know where to start, lets try this. First put the sails into an environment where they can work.

 

Straighten the mast athwartships.

This will get easier in time. Make sure the mast is dead center in relation to the beam of the boat; that it does not lean to one side or the other. You can make a device that rests on the shroud racks that will act like large drafting divider looking for the apex to center on the mast. This is close enough to start. Another means is to remove the boat from the cradle onto a level surface and measure the tip of the mast to that surface. Roll it over and measure for the other side. If you are using lower-lower shroud lines, disconnect them. Make adjustments to the upper shrouds until the measurements are the same on both sides. This process will only put the top of the mast in the center of the boat.

 

Now, sight down the mast from the top and consider the bends. If you use the divider mentioned above, the mid section can be centered faster. You can also measure from the surface to the spreaders like above. However you do it, if the mid section and the top is centered, the mast will be straight to that point.  

 

If you are having trouble because the head of the mast is continually bent, hold the mast firmly at the spreaders and wiggle the top of the mast. If both of your jumper wires terminate at the spreader area and thread through a hole at the crane above, you will be able to place the top in a straight position and it will stay there. I learned this at the last race of the season. The jumper wire loops through a hole on the leading edge of the crane and can slip. The handling of the rig has caused the top to slip sideways on the jumper wire. Consider this if you are having trouble.

 

When you have a straight mast, top to bottom, locknut your adjusters. Now reattach the lower-lowers and snug them up. I place mine only tight enough to prevent the mast from bulging forward with any pressure from the vang. If you have not seen what the vang can do to the mast, loosen things and then extend the vang (lengthen it) and you will see the mast concave with the trailing edge aft. So, firm them up and after checking the mast again, locknut those adjusters.

 

Straighten the mast to the desired rake. 

With some sort of right triangle, straighten the mast fore and aft. It is handy to cut notches in the triangle for fittings on the deck and the leading edge of the mast. The slope of the fore deck is about 2-1/2 degrees. I have never done the Trigonometry to determine how far aft this places the mast head from the waterline but it seems to be the acceptable position, though most in the fleet do not check it. For now, you should do it with the triangle until like me, you find a better way or reason to place it somewhere else.

 

Movement of the mast rake is generally controlled by a bowsie adjuster on the string portion of the jib fore stay. On this site, you will see that the fore stay is a static length between the 59" position on the mast and the jib boom. In this case the mast rake is controlled by an adjuster on the jib boom by changing the length of jib swivel connector to the jib rack. This method of adjustment moves the entire rig in one piece as one unit.  That is our preference. The other method, mentioned above, will also work and will move only the mast and mainsail to the rake desired.

 

The jib swivel was described in the Optimizing manual and made sense to me. The entire rig works as one unit, so move it together; I can't tell you for sure that one is better than the other. The bowsie method is much easier to install. The static jib stay length method is precise and very critical during the initial erection of rig during construction.

 

Backstay Tension (BST)

Jib sag is important to the performance of a jib. Wind pressure on the jib causes the forestay to sag which is the same as bend in the mast. You can control the amount of sag by placing tension on the forestay. This is done with the backstay wire. The sail maker cuts the leading edge of the jib for a specific sag measured in 1/32" increments. When you hear someone refer to a #4 jib, it means the jib has been cut for 4/32" sag on the forestay. Four, six and now I have heard of a 6+ seem to be the most popular. The higher the number is said to be better for a more broad range of wind. However, this tends to be less precise to the more discriminating sailor. Broad is good for me. I have not seen a steady wind at any regatta yet. The sag determines the entry angle of the jib luff. This is the leading edge of a wing and that angle is important to everything that happens behind it.

 

As the wind pressure increases the jib sag increases. To keep the jib in its design limits, BST is changed according to the wind speed. In turn, this tension is transmitted to the forestay through its mount on the mast. The sail maker will suggest certain tensions for wind ranges. I have a chart taped to my box of stuff that reminds me of these numbers. They are just a guide but I live be those numbers. It will take some experience to venture outside of what has been passed down.

 

Set the BST to the cut of your jib and the wind on the course. Oops, no tension or wind meter? Ask what others are doing till you find a need for these things. Many do this by feel and instinct. I can't. I need the numbers.

 

Mast Bend

Now look down the mast again. If the BST is high there will be a bend in the mast. It is easy to understand because the BST is pulling the top of the mast aft and the force on the forestay is 13" below. This bend may be okay if it is not too much.

 

Most mainsails are cut with what is called a luff round. This means that the leading edge of the sail is convex with the mid section more forward than the head and the tack. Our mainsails here are cut to a 1/4" luff round. Now if you bend the mast to match this round (curve) then the mainsails will fit smoothly along the mast with no bubbles on the luff. This is a nominal setting that will be recommended by the sail maker. You will notice when this is not right. What you are looking for is a nice smooth leading edge curving away from the mast into the camber of the sail from head to tack. If it is not smooth you will see a break in the camber curve within an inch off the mast connection on the luff. That means the mast is not in harmony with the mainsail.

 

Now here is where this dummy differs with most of the fleet. It has been my thought that you change tension and/or move the lower shroud mounts only as needed to obtain this curve. In my different view, I see the lower shrouds connected at the spreaders which are about halfway up the mast. If I can pull that portion of the mast fore or aft with those shroud wires I can control the bend of the mast without disturbing the BST. It has been my experience that somewhere around three knots of wind, the BST creates a bend in the mast close to the designed luff round. I always attach the upper shroud mounts in line with the mast when rigging. If a higher BST is needed I will have the lower shroud mounts aft of the uppers and tensioned to pull the center of the mast aft to match the bend I want. Remember, the greater the BST needed the more bend you will have in the mast. Conversely, in light air conditions where the BST is light, I will move the lower mounts forward of the uppers on the shroud rack and tension to pull the mast forward in the bend I want.

 

I arrived at this process because of my concern for the BST and its relation to jib sag. This seems to be the priority. I mentioned somewhere in this rambling that through the summer I tended to flatten the mainsail more in the light air conditions. I attempted to loosen the lowers (they were mounted aft of the uppers then) to allow the center of the main to flatten. I did not like that because the rig became loose to my liking. So, it was at Stowe that I moved the mounts forward to pull on the mast and and flatten the main while never changing the BST.

 

Now, with the mast straight, the BST set to the wind and recommended jib sag allowance and with a slight bend in the mast for the main luff allowance, study the rig. Learn what this looks like. Think about it. Be sure to lean the boat over and study the view down the mast also. Be conscious of any irregular sail shape, particularly in the mid section luff of the main.

 

Camber Of The Sails

Start out simple. You have heard this before but three fingers on the main and two on the jib is a good start and it will work in most cases. The idea of this writing is to get you in the water with some understanding what is happening and with enough boat speed to control the boat. This will put you there.

 

With the boat lying on the deck, in no wind, the sails will drape. The curve of the sails, away from the booms, is the camber and it can be measured but we will not do that here. Also, that camber will be greater at one point along the foot of the sail. That point is the draft and it too can be measured but we will not do that either. If you study this view you will see an exaggerated profile of the cord of a wing. If it is smooth and appeals to you then your work above has been beneficial.

 

You control the depth of the camber with the clew adjuster and the position draft with the downhaul. I tension the downhaul just enough to barely see a hint of wrinkle in the sail. More in light air and none in moderate air. I have been advised by my sail maker that four ounces of tension is the maximum for his design. I live be that. He is the professional.

 

This is a good beginning. I found through the summer that I tended to loosen the jib a bit and tighten the main a bit. So, that it is a loose two fingers and a tight three. Just a thought if you are fooling around. I am also moving toward recorded settings to markings on the boom. This is a slow process as experience confirms the settings.

 

Sheet Lines

Run the winch all the way in and set the jib trim control to center. Adjust the sheet line so the main boom will be in tight and very close to the centerline of the boat. Now adjust the jib sheet line till the boom is pointing at the leading edge of the shroud rack if you have jib trim and in about ½” from there if you do not. If you have the main tight and you move the winch in and out just a little, you will notice that at close haul the rig will tighten up just a bit. This is caused by a downward pull on the main sheet line as the boom travels closed to the centerline of the boat. This phenomenon tensions the leech of the main, reduces twist in the top third and flattens the center section just a bit by bending the mast aft. If you are new to this and do not notice these changes, just push down and the end of the boom and watch for the changes till you see the pattern. It is not important that you understand this at the moment but it was a point in this writing to say that this action, at full close hauled, is called sheet vanging.

 

Sheet vanging is not part of the tuning process at the beginning level. However, if you follow the process above it will be available to you on the water when you progress to understanding what it can do for you. For now it is suffice to say that it is a means of changing the tuning of the rig on the water, legally, without any additional servos. It will allow you, in certain circumstances, to cover in an overlap and point to hold that cover. It will do other things for other situations but this is the biggy. So, if you have been wondering about the term, this is it.

 

Sail Twist

Now release the tension on the sheet lines by letting out the winch line just a bit. Not more than a quarter of an inch. Lean the boat over in the cradle so you can sight down the mast and see the drape of the mainsail. The bottom batten should be very close to parallel with the centerline of the boat. Now concentrate on the second batten down from the head. This should be parallel to the boom or even outward to the lee a bit. Adjust the vang till it is. It is this upper third of the main that is twisted to match the natural tendency of the wind.

 

By changing the vang you introduce change to the rest of the rig. As the vang moves the boom vertically at the clew, tensions change along the mainsail leech and the top of the rig. It will also change forces forward of the gooseneck on the mast. So, look the mast over real good. Check your BST. Here is where a tuning cycle starts. Keep going around till you have the mast right, the BST right, the camber right and the twist right. In your travels note that a slight movement in the vang makes a large change in the twist. When you have it right you might consider marking the vang adjuster to simplify this process on another day.

 

If there is wind to fill the sails bring the boat upright to set the twist in the jib. If not, leaned her over in the cradle. Adjust the topping lift till the leech curve of the jib matches that of the main. This is essential to the coordination of the air flow between the two. If I err at all here it will be to much. What the jib does on the water is my best indicator as to the harmony of the sails.

 

Now take some time to get familiar with the look. Until you have confirmed settings that you like, you will have to rely on a good look. This is not bad as it is here that some intuitive insight may appear. Instincts can be relied upon particularly as you gain experience. The process may seem long and complicated at first but it is a drill that once learned will pass in just a few minutes. Once you have set some of the adjustments, they will remain till you return another day. The first day on the water with a new boat is the longest and the hardest because you want to sail. Be patient.

 

Into The Water

Play with it just a bit. Bring her back to you and bear away into a beating tack so you can see the leech curve of the sails. Be sure the winch control lever is out just a bit and the trim control is centered. Don't point up too high so the sails will stay filled. Study the slot. Are the leeches parallel? Are the booms offset, like on the dock, with the jib boom out more? Is the top of the main twisted to leeward? If not, you know what to do.

 

Using the same winch position, place the boat on a beat so you can see the profile of the rig. Is the main filled out smoothly with no major wrinkles? Are there any bubbles along the luff of the main? Is the entry angle of the jib smooth, not heavily curled off the forestay? Are there any wrinkles horizontal along the luff due to a loose downhaul? If not, you know what to do.

 

Point the boat downwind. Is the main out 80 to 85 degrees? Is the main sheet line taunt with the boom? Is the jib out about 90 degrees? Good!

 

Now come around into a beat where you can see good. Slowly bring the boat into the wind and watch for luffing. Whatever luffs first, concentrate on that:

If the jib luffs real good and before the main, bring in the trim a little. Keep coming around and trimming till there is just a hint of luff before the main. What you are looking for is the correct setting for the jib sheet line that will give you a trim center set. In this initial setting above I have never seen the jib off more than a quarter of an inch.

If the greater part of the main luffs before the jib, make sure the winch control is at a loose close hauled position. Let the jib trim out to see if it will stop. Some mainsails like to breathe, as they say in this business, requiring a larger slot. Make sure you have three fingers to a tight three in the main camber. This luffing can occur but rarely, something has to be real wrong for it to happen. Something you will notice quickly.

However, it is not unusual for the top section of the main to luff. If your top tale tail is fluttering off to leeward then there is too much twist. When you come in try a quarter of a turn on the vang...no more... till you get it right. Ideally, you are looking for that tale tail to stream straight back.

If the tale tail is curling to windward then there is not enough twist in the main.

In this process be aware of where you are making changes that will affect other areas. Make adjustments that will get your TX controls back to a nominal position. You are looking for the sails to work in harmony and luff in harmony. If you get lost, start over, get back to the beginning. It is hard work but very rewarding in the end.

 

Though the summer I found that I like to have the jib give me just a hint that it is about to luff. With this and no overlapping boat to interfere, I could run a scalloping tack. You will hear about his later; another Easter egg this dummy found.

 

Synopsis

Straighten the mast athwartships.

Straighten the mast fore and aft with rake.

Set the back stay tension.

Set mast bend.

Set the camber and draft of the sails.

Set the close hauled position of the booms.

Twist the sails.

Water test your work.

Balance the boat. Lessen weather helm.

This is my basics to tuning with some hints of the future. I hope I did not forget something huge. It is raining and blowing and cold outside.

 

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