Sail Planning

Choosing the sails and sail handling setup on Puffin was a fun part of the process, but also a bit nerve-wracking as there are so many factors to consider and trade-offs to make. It’s difficult and expensive to fix mistakes after the boat is built, so every detail has to be thought through.  It took a lot of discussions and research and I really want to thank Benjamin and Matthieu at Outremer for their detailed advice and patience with all my questions!

I feel like sails and sail handling systems are possibly the most critical areas of the selection process when purchasing a new catamaran. I’ve had poor setups in the past and they make it a frustrating experience to handle and trim the sails and can be downright dangerous in certain conditions. A good setup gives you the confidence to handle any conditions you encounter, and can make your boat a pleasure to sail, so it’s well worth the effort to get it right.

The basic setup on the 4X is good, but after previous lessons learned and my goal of configuring Puffin for easy single-handed sailing, I needed to go over every detail to make sure we would end up with a solution that meets all our needs. In this post I will go over what we are trying to accomplish with our sail plan and the solution we have chosen for Puffin. I’m going to cover the important things I wished I had known when I bought my other boats, and what I have learned from my earlier mistakes. This post gets a bit technical, so for those that want to skip the science lesson, here are the top three things I wished I knew when I was buying my first boat:

  1. It’s a sailboat. Sails matter, a lot! Don’t skimp. Good sails and sail balance can make you love sailing your boat. Poor sail balance can make you hate it, and can put your boat and lives at risk
  2. Most manufacturers put cheap sails and grossly inadequate sail handling systems on their boats. They do this to keep the price low, and because virtually nobody attending a boat show wants to talk about sailplan design. Beware of this, you’re buying a sailboat not a motor boat, see point 1!
  3. Work with a manufacturer you trust, and talk to them about your sails and sail handling. Good manufacturers like Outremer are happy to do this. When they give you advice, listen to them! They have seen just about every scenario you can imagine and they know what works and what doesn’t out on the water.

Our design goals

Let’s get started with Puffin’s sailplan. In order to determine the best solution, I had to first define our goals. Here’s what is important to me on our boat:

  1. Excellent light wind performance – I talked about our goals for light wind sailing in the Chasing Performance post. A lightweight, well designed boat is fundamental to this, but we also need sails that can provide maximum power with minimum weight.
  2. Easy reefing – We want the minimum amount of sail up at any time to maintain our desired boat speed. This means that we will spend a lot of time sailing with one or more reefs in the mainsail. We need to be able to easily take and remove reefs, and we need to make sure there is minimal wear and chafe when sailing long distances with a reefed sail.
  3. Balanced rig – As we reef the mainsail we also need to reduce the headsail area to keep the boat balanced and minimize the load on the  autopilot. The headsail area has to be easily adjustable and the location of the center of effort must move back towards the mast as the headsail area is reduced.
  4. Controls at the helm – We want to minimize the need for going forward to make changes to the sails, so most of the operations need to be done from the helm station.
  5. Single-handed operation – All sailing maneuvers on the boat need to be as easy as possible when performed by a single person
  6. Storm mode – We need to have a storm configuration that’s simple and safe to configure and can handle winds in the 40-50 knot range

Prioritizing Tradeoffs

There’s no one or perfect answer in any of this, so every decision becomes a compromise. I had to determine my priorities for choosing among different alternatives. I decided that I would start with high performance sails, but after that I would put ease of single-handing above performance when making tradeoffs.

Our Sails

We chose North 3Di Endurance for our 68 square meter mainsail. The sail is fully battened with three reef points. We added three colored lateral bands to assist with trimming. Although the sail in the image has numbers on it, we deleted the sail numbers from our sail. They’re ugly and unnecessary for cruising.

North mainsails are almost half the weight of the equivalent hydranet sail and they are able to keep a good airfoil shape in light winds. The downside is they are not as tough as hydranet and they will chafe if not handled carefully.

For our 55 square meter Genoa we chose North 3Di Endurance.

We get the same benefits with the 3Di Genoa as the main. Significantly lighter and holds an excellent airfoil in light winds, so more power. There are two donwsides to 3Di genoas. They have less resistance to chafe, and they don’t roller reef very cleanly. Our Genoa is on a roller furler and because of the molded airfoil shape of the 3Di sail they work  best when fully unfurled. When furling partially to reef, they develop creases along the luff and lose performance. This sail uses a new system by North to reduce the creasing along the luff when reefing. I’ve not seen or used this, so will have to report back later on whether it works or not.

We are adding a staysail to Puffin, which is not standard on the 4X, but is offered by Outremer as an option. In my experience, catamarans over 40-45 feet should have a staysail (I explain why below). We added this on Wildling, and it completely changed our sailing experience. We were able to point higher and drive the boat easily upwind in strong conditions, and we maintained helm balance as the sails were reefed.

Our staysail on Puffin is on a movable inner stay which is tensioned in place when needed. I expect to be using the staysail a lot when sailing upwind, so we are rigging it to use the self tacking track. This is the same track the Outremer 45 uses for its self tacking jib, which we don’t have on our 4X. Because it’s on a movable stay, we are not using a roller furler, instead the sail will be hanked on, with a single slab reefing point.

North Staysail 3Di Nordac. Full sail is 26 m2 with a single slab reef at the foot reducing to 18 m2. Self tacking on a moveable inner stay. Because of the small size, the sail is easy to deploy from a deck bag. When not in use, the sail is stowed and the stay relocated to the mast foot so it doesn’t interfere with tacking the Genoa.

We had to make a tradeoff here. The optimum staysail size recommended by North is 32 square meters, but that would require the sail to be rigged slightly overlapping the mast and not self-tacking, making it more work to route the sheets when deploying and more work to tack. From past experience I know we will spend a lot of our time upwind under staysail, so because my tradeoff criteria favors easy single-handed sailing over performance, I went with the smaller, self-tacking staysail.

Storm Jib – North high strength Dacron. 12 m2. Hanked on to inner stay. Used with triple reefed mainsail

The storm jib takes care of winds in the 40-50+ knot range. It hopefully won’t see much use. I needed ours on Wildling when we sailed 12 hours in 45-50 knots and was damn glad to have it, so there’s no question for me about getting one on Puffin.

The Balance Problem

One of the lessons I learned the hard way is the importance of rig balance when sailing upwind in developed conditions. This is so important, and so seldom mentioned by boat manufacturers, that I’m going to go into the science behind it a bit to explain what it is, and why I care. Let’s start by looking at a boat with full main and jib in balance to understand the forces involved.

Full mainsail and jib on a balanced rig. Locations and distances on this diagram are my own estimates, taken from a scaled drawing. This data is not provided by, or endorsed by Outremer, I’m just trying illustrate the point.

Imagine that our boat is sailing upwind with the wind at around 45 degrees to the bow. There are three important locations where a force is being exerted on the boat:

CE-main: This is the center of effort of the force pushing the mainsail sideways

CE-jib: The center of effort of the force pushing the jib sideways

CLR: The center of lateral resistance. This is like the post of a weather vane and opposes the sideways movement of the boat.

You can imagine if the boat is in balance and the force acting at CE-main is increased, the stern of the boat will tend to get pushed away from the wind. Also, if the force at CE-jib is increased the bow will get pushed downwind. If they are equal the boat will not rotate and will be balanced. You will feel this on the helm. The boat will sail on course with no helm pressure. When the forces are out of balance, the only way to stay on course is to compensate with the rudder. A small amount of rudder is fine, a large amount will overcome the auto-pilot, and if the force imbalance gets too large, the rudder can no longer compensate and the boat can no longer be held on its current course.

The relationship of forces can be represented by a simple lever diagram. In our high school physics class we learned the mass (or force at the CE for us) x distance on one side of the center of resistance is equal to the mass times the distance on the other side when the system is in balance.

Moving M2 further away requires a reduction in the force to maintain balance.

Just for fun, let’s do the math on our theoretical 4X diagram above. I’ll just pick a number for the force acting at CE-main because it doesn’t matter what the actual force is, what we want to understand is the balance relationship between the main and jib as a percentage of the mainsail force. So I’ll just use 100 for the force at CE-main and then solve for the force at CE-jib. This gives the following:

forceCEjib = (forceCEmain x D1) / D2

forceCEjib = (100 x 2383) / 3365

forceCEjib = 71

Balance ratio = 1 This rig is perfectly balanced

Everything is good here. Both sails are balanced around the CLR. The boat will maintain course, driving well with no helm pressure. (In reality the forceCEjib would be a bit less than this, and there would be a small amount of pressure imbalance turning the bow towards the wind (weather helm). This would be overcome with a degree or two of rudder, but that’s not important for this discussion).

Now, let’s see what happens when the wind builds and we reef the sails. We’re going to take two reefs in the main which will reduce it from 68 m2 to 41 m2 (about 40%) and we’re going to furl up our jib 40% as well. This is shown in the next diagram.

With two reefs in the main and a 40% reefed jib, the distances have created a large imbalance

This configuration shifts both the CE locations forward, but it’s not until we do the math that we realize the magnitude of what’s really happened.

We can find the new balance ratio as a percentage of mainsail power by comparing the magnitude of each side of our balance equation. We will reduce both the main and jib force acting at the CE by 40% (by taking two reefs) and use the new distances measured on the drawing. Here’s what we get.

forceCEmain X 60% x 1768 = 60 x 1768 = 106,080

forceCEjib x 60% x 4960 = 42.6 x 4960 = 211,296

Balance ratio = 1.99 The jib is exerting double the mainsail force sideways

This dramatically changes our ratio of forces, and now the jib is generating twice the force of the main. The bow of this boat is being pushed hard to leeward and the rudders may not have enough surface area to compensate. The only solution is to keep furling the jib until the rudders can exert enough pressure to maintain course. Unfortunately we have to furl a lot because as we furl, the CE-jib keeps moving forward. With the further reduced jib we lose a lot of our power, the boat starts to slow and can no longer drive as well through the waves created in these conditions, this slows the boat down ever further. The dagger-boards lose lift as the speed reduces and the boat gets pushed to leeward making it even harder to maintain course. This leaves the helmsman with two choices. Change course or start the engines. On most catamarans at this point, the sails get stowed and the engines take over.

So What’s the Solution?

This problem is very solvable, but it requires a different upwind headsail setup. What we need to be able to do, is move the headsail CE backwards towards the CLR of the boat as we reef the sails. Our staysail will do this for us because it’s rigged on an inner stay, much closer to the mast than the roller furling jib or Genoa. The following diagrams show our sailplan configuration on Puffin, incorporating a staysail at different reefing points.

North reefing plan using a Staysail configuration on an Outremer 4X. The total area can be reduced in line with conditions while maintaining a balanced rig.

This is why a staysail is such an important safety feature on a catamaran and why we are adding it on Puffin. I mentioned in the performance post that we anticipate sailing a considerable amount of time with reefed sails, so having a staysail is even more important because we will so often be in a sail configuration where the staysail is the ideal headsail for the conditions.

Sail Handling Systems

Now we know what our sail configuration is going to be, the next step is to look at how we will raise, lower, reef and trim the sails to suit the different conditions.

The standard 4X sail handling design is very good, but there were a few changes that I wanted to make to make it a bit easier for single-handed sailing.

Fixed Carbon Mast

The biggest change to the base 4X design was my choice of a fixed, carbon fiber mast instead of the standard rotating mast. We give up some performance, but we gain the following benefits:

  1. Rope clutch for main halyard moves from the side of the mast to the salon roof in front of the helm station. A rotating mast needs to be free to rotate, so the halyard has to be blocked on the side of the mast. This means going forward every time the sail is raised or lowered and adds steps to reefing operations. The fixed mast lets us move the halyard blocker to the helm station.
  2. Rope clutches for reefing lines move from end of boom to the salon roof in front of the helm station. Same as above, the rotating mast requires crew to go to the mast end of the boom to release and secure the reefing line blockers. This is not needed with the fixed mast as these relocate to the helm.
  3. Removed mast angle control lines and blockers – The rigging for controlling the mast angle is not needed. This saves weight and cleans up the salon roof and helm station a bit.
  4. Simplified instruments – The mast angle sensor is not needed, which eliminates a potential point of failure and maintenance. Also, we can locate the radar dome on the mast spreader and not have to worry about the unreliable software compensation for mast angle when displaying radar plots.
  5. Redundant navigation lights – A fixed mast allows us to add a tri-color nav light at the mast head, in addition to the standard set of deck level lights. This is an extra level of safety and protects us if (when) we have a nav light go out.

Mainsail Reef Hook

This hopefully solves a problem I have struggled with on both my previous boats. When reefed, the line that secures the mainsail clew to the boom is under constant tension. It is the source of loud creaking noises, and the contact with the low friction ring at the clew causes a lot of chafe. We sail with reefs in a lot, so I really wanted to solve this issue. I discussed it with Matthieu, and it turns out Outremer are now offering an option on their boats that addresses this problem.

Facnor Reef Lock on 1st reef point

The Facnor Reef Lock captures the clew reef shackle and takes the load off the reefing line. No more chafe, and no more creaking! We are adding this to Puffin on our 1st reef point, which is the one we use the most and also places the most load on the reefing lines.

Remote Control Furling

The final sail handling modification was the addition of electric winches and remote control buttons so that the headsail can be furled on all points of sail single-handed. We converted the port cockpit winch to electric for ease of headsail furling. We made one of the port helm position winches electric to make it easy to raise the mainsail and spinnaker halyards and to lift someone up the mast. And we made the winch on the starboard side salon roof electric to make it easy for Robin to trim the Genoa if (when) I get injured.

The port cockpit winch handles the furling line for the Genoa. I want to be able to furl single-handed on starboard tack so I added an extra high speed winch button behind my feet at the helm station. To furl I put the furling line on the cockpit winch, go to the helm station and put the Genoa sheet on the winch, then ease the sheet as I push the furling winch button with my foot.

We added another remote control button for the port cockpit winch at the starboard side Genoa sheet winch position. This allows me to furl the Genoa single-handed when on port tack. To furl I put the furling line on the cockpit winch, go to the winch at the starboard side of the salon roof and put the Genoa sheet on the winch, then ease the sheet as I push the cockpit winch button with my foot.

What about downwind?

Downwind sails were pretty easy. I used the heck out of our Code-D Gennaker on Wildling, so I’m going to get another one for Puffin. It’s just so easy to hoist, stow and furl compared to a spinnaker, and what it lacks in performance it more than makes up for in ease of use and low stress sailing. The only modification I made to standard is that I am using a Karver KF8 furler for the Code-D. These things are bullet proof and very low friction, so they make it easy for either Robin or I to furl our Gennaker in windy conditions.

Karver KF8 continuous line furler for the Code-D

I’m also adding a (highly controversial) symmetric spinnaker. Most performance cruisers hate these things, but I like them. Ours is small with a heavyweight fabric (for a spi) and I use it when we’ve got moderate wind but large waves. In these conditions, it can be very uncomfortable sailing on a reach and I find I can keep everyone on board healthier and happier by dropping the main, setting the symmetric and going dead downwind. We’ll never set any speed records with this sail, but in some cases the relief it provides in nasty conditions is worth its weight in gold.

13 Comments on “Sail Planning

  1. Hi Doug, great post and validates a lot of my thinking. We are building a much smaller Richard Woods design and my thinking regarding the rig set up is similar, particularly having everything manageable from the cockpit. Thanks fo the clear explanation on balance, I am having an inner forestay to run a storm sail on and now thinking about also adding a larger staysail in addition to the storm jib. Only major departure for me I’m choosing a reefable hanked on headsail rather than having on a furler. The logic here is sail shape when reefed and I’ve set up so we can both reef & douce from the cockpit. Throughly enjoying the articles. Cheers

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    • Hi Nigel, thanks for the comment. I agree with your thinking on the headsail. It might be worth investigating the staysail option instead of reefing the main headsail, that way you could still go with a furler and just never roller reef. The French multihull racing sailors do this and call it a stockeur. It’s either fully out or fully furled, there’s no in between. We did this on our staysail on Wildling and it worked great. The advantages are that you don’t have to go all the way forward to douse your forward headsail if things get crazy, and you get perfect sail shape on your hanked on staysail when your headsail is too big.
      Cheers

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  2. Hi Doug. I’m glad to see that you’re getting a new boat. After reading your posts on sailwildling and now puffin, I’ve come to a conclusion- I think you have more fun building your boats than you do actually sailing them (especially motoring in light air)..

    Your explanation on reefing was great as far as it went, but you focused on moving ce without addressing clr. Doug, could you play with the daggerboards on Wildling when underway? Reducing the daggerboard area will move Clr. You may be able to postpone reefing by raising the daggerboard by about 20-30 cm.

    Remember-“Fast is Fun” http://merlinyachtracing.com/about/

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  3. This is all good stuff and appreciated. Helps us first-timers cut a lot of corners when considering boat features.

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  4. Doug, curious if you guys are going to put another upsideup system in after your experience with it on Wildling?

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    • Hi Josh,
      The UpsideUp system is very good, and they have continued to advance it since we installed the system in Wildling. I decided to not put it in Puffin because the forces are so much less, I feel more confident that we can keep the boat in a safe configuration. I would definitely recommend it for a larger multihull though.

      Liked by 1 person

  5. Is Puffin the first white 4x? In all the other pics I’ve seen of 4x’s, they have been grey with stripes on the quarter.

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    • The original 4X colors were gray hulls with black mast, black longitudinal beam and bowsprit and black crossbeam. Then they went to white hulls and kept the rest black. I don’t like the black mast and beams so we changed them to white. I believe Puffin is the first all white 4X that they have done.

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  6. Hi Doug, many thanks for sharing your considerations, very valuable, I learn from all of them! I have a couple of questions if I may to see if I can ’steal’ some of your ideas. We have an Outremer 45 (2015) – Vassiliki, so your boat but 1-2 knots slower, without the carbon stuff and the transom extensions:) How is the inner forestay supported and in your mind could this be retrofitted – I like the idea of a smaller head sail closer to the center of the boat in windy upwind conditions?

    And on the Reef hook, I agree the creaking can really get on your nerves! I think, in addition to the reef line you also need an ‘unlocking’ line when you want to shake the reef? Presumably this line is also led back to the steering wheel position, but if so, how is this done?

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    • Hi Adriaan,

      Regarding the inner forestay, The longitudinal beam on the 4X is a composite, carbon-reinforced GRP spar required to take the high loads of the staysail. My assumption is that due to the longitudinal beam construction of a 45, you you can’t fit a staysail, but Outremer will need to answer this question. There may be some modifications they can do?

      On the reef hook. There are two lines led back to the helm station. One line to pull the leech down and engage the hook, the other line to release it.

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