Full Length Battens-4: The Hardware.

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I hope the earlier essays have covered the issues surrounding the full batten question from the sail performance, efficiency & speed perspective.

The ease, or lack of it, with which a FB mainsail can be operated during the various maneuvers a crew must make while at sea full battens offer these advantages:

On boats with aft sweep to the spreaders, it is important to have the area where the batten pocket bears on the rigging to be reinforced with sacrificial chafe protection.

On boats with aft sweep to the spreaders, it is important to have the area where the batten pocket bears on the rigging to be reinforced with sacrificial chafe protection. This image shows just such protection on the pocket of a Deerfoot 60 mainsail Hood built. While chafe protection is a good detail to have on your sail when going of into the open ocean, it is more important on FLB sails due to the grinding effect the batten imparts on the stays, or anything else the batten and sail are bearing on.

 

  • The mainsail is much quieter when flogging the battens reduce the frequency at which the sail flaps-This is because the stiffness and mass of the batten resists the wind force more than a mere “cloth.”
  • The effect of the batten separating-pushing the luff from the leech makes it easier to get a hand full of sail and to some degree put it where you want it, particularly if there is some kind of boom bag for the sail to settle in.
  • Full battens are more effective at keeping the sail constrained between lazy jacks, even more so if the lazy jacks are located with respect to where the reef points and the batten’s leech ends are.

The real trick that makes ALL of this work as an integrated system is to mate the hardware to the boat, the sail and the intended use of the boat. This requires a combination of learning about the pluses and minuses of each version plus some other contemplation: Much of this information can be supplied by the sail makers and or rigger, but as with any business, they most likely have their own favorite hardware, mainly because they are used to in.

In no particular order some of the details to decide or to think about before even picking up the phone are:

  • Track or no track and
  • Ball bearings or no ball bearings.
  • Number of battens
  • Will the battens be installed from the Leech OR the luff
  • How the batten pockets will made to will resist chafe
  • How the sail is to be captured when it falls down
  • What you are realistically going to do with the boat/sails/battens–The further offshore you go, the higher value the most friction free gear you can get will be.
  • Stack height
  • Reefing details
Making sure the reefing system is coordinated with, in particular, the placement of the battens and cars is one of the important details to get right.

Making sure the reefing system is coordinated with, in particular, the placement of the battens and cars is one of the important details to get right.

This installment will begin to cover the available hardware for making the most of the benefits of the full batten sail which are to my mind “ease of handling”. It should be noted that the bulk of the following information pertains to the hardware I have seen and or had experience with in the US.  Regardless of hardware the principles are the same.

First off a definition is in order for the idea of “ease of handling”

For this discussion ease of handling includes:

  • Any hardware-Tracks cars batten boxes etc.
  • Or sub-system-Lazy jacks boom bags etc.
  • Or technique, practice skill in handling the boat during sail handling activities

OR

  • That which makes the manhandling of the mainsail on the boom easier and/or less stressful, and/or safer, whether hoisting, lowering, reefing or unreefing.

Reefing in a seaway is potentially one of the most hazardous parts of sailing a boat. The crew is, often out of the cockpit, it is blowing, often quite hard, there is a sea running perhaps quite large and there is the personal  stress factor, both on the part of the crew member doing the work and the master worrying about his crew….

wx map 13 April 13

When your weather map looks like this you better be sure that all the gear, especially the sail handling gear, on your boat works 100%, is easy to work, fast,simple and tested.

Traditionally one of the hardest parts of dealing with a mainsail is the friction generated mainly by the slides operating in the track. This is closely followed with what to do with the bunt of the sail after the reef is secured. On modest sized boats this is not so much a problem. If the “Depth” of the reef is say 4,5,6,7 feet- and boat that has three reefs at 7 feet apart might have a rig close to 45-50+ high feet, so perhaps a 40 footer. Depending on all manner of variables it may be sufficient to let the bunt flap to leeward, although personally I would roll it up and tie it off. Boats with a larger gap between reefs of course get progressively larger; the size of everything goes up as do the loads and the weight of everything. The requirements, desirability and the cost (all equaling value) of using low(er) friction luff sliders increases with the size of the boat, the sail and owner’s horizons.

As if this writing, I identify the following categories of luff slide hardware-And yes all of it can be used with a conventional sail with just leech battens too. These categories are:

CARS/SLIDES: With ball bearings and without.

This is a Harken ball bearing car for the batten box to attach to. Originally the red dummy track was used to keep the balls in the car. This has been improved on now so that the balls are held captive in the cars, minimizing one of the great arguments against ball bearing cars.

This is a Harken ball bearing car for the batten box to attach to. Originally the red dummy track was used to keep the balls in the car. This has been improved on now so that the balls are held captive in the cars, minimizing one of the great arguments against ball bearing cars.

Antal track slider & Toggle with Antal leech loading batten box.

This is Antal track slider & Toggle with Antal leech loading batten box.

TRACK: Those that employ a dedicated track that needs to be installed into the existing mast groove with track. AND NO (dedicated) TRACK-Those systems whose sliders operate in the mast’s groove.

Dedicated track requiring attachment to the spar is a hallmark of a high end ball bearing system

Dedicated track requiring attachment to the spar is a hallmark of a high end ball bearing system

BATTEN BOXES: Those that are adjustable, to tension the batten in the sail and those that merely accept the batten and the batten tension is applied elsewhere, usually from a lashing or Velcro arrangement on the leech.

Batten boxes come in almost as many flavors as the systems themselves. Top two items, L-R: Antal slider with leech load box, Tides Marine slider with their leech loading box. Bottom three, L-R Sailman box and slider from Bainbridge, Rutgertson box and slider and a Battslide brand box with toggle.

Batten boxes come in almost as many flavors as the systems themselves.
Top two items, L-R: Antal slider with leech load box, Tides Marine slider with their leech loading box.
Bottom three, L-R
Sailman box and slider from Bainbridge. A Rutgertson box and slider
and a Battslide brand box with toggle. This toggle would fit into the Harken batten car, shown above, in the red dummy track and all of the others reference here except Dutchman.  Not shown is another box called PNP, roughly similar to the bottom three.

 

This detail shows a leech loading batten pocket tensioning mechanism. BUT not only should the leech tensioning method tension the batten, it needs to be engineered in a way that makes it really hard to loose the batten out the end, as when flogging the sail in hard wind while reefing or attending to some drama aboard. This is a good reason for the luff loading battens with adjustable boxes. Adjusting the tension on the batten is a lot easier too-You do not need to be scrambling around up on the boom to get to the leech of the sail, rather you can stand at the mast and use typically a hex socket or sometimes a screwdriver.

This detail shows a leech loading batten pocket tensioning mechanism. Not only should the leech tensioning method tension the batten, it needs to be engineered in a way that makes it really hard to loose the batten out the end, as when flogging the sail in hard wind while reefing or attending to some drama aboard. This is a good reason for the luff loading battens with adjustable boxes. Adjusting the tension on the batten is a lot easier too-You do not need to be scrambling around up on the boom to get to the leech of the sail, rather you can stand at the mast and use typically a hex socket or sometimes a screwdriver. In this image you can see a length of light spectra lashing , far right, secured through the batten end and around the webbing strap. The batten is tensioned by a lashing (not installed yet) passing through the webbing and the grommet on the flap, to the left.

TOGGLES: These are usually metal devices that connect the batten box to the luff car. They are superior to merely webbing the batten pocket to the car because they maintain a separate specified rigid distance between the sails edge and the car. For the batten box to slider connection a more or less standard M10 and M12 threads on the studs entering into a matching female on the box. The boxes in the image above the one of the leech loading pocket detail, are all connected to their respective slides by the toggle.

Virtually all toggles are a variation of this version on a Rutgereson roller slide.

Virtually all toggles are a variation of this version on a Rutgereson roller slide. Most batten boxes have a matching M10 or M12 female into which the stud threads. This slider BTW is one of the crossovers in that the ball bearings are in the wheels, which bear on the outside of the mast tunnel-No dedicated track required.

CROSS OVERS: There are at least a couple of products that offer in-mast sliders that require no dedicated track and have ball bearings or some kind of roller on the slider.

This is one of the most elegant cross-overs-The Ronstan Ballslide. They come in two sizes a 6 and an 8

This is one of the most elegant cross-overs-The Ronstan Ballslide. They come in two sizes a 6 and an 8. You can see the “feet” held in place by the screw, on the left of the image and the balls in their cavity. If memory serves the numbers refer to the diameter of the balls.

 

 

Ronstan ball slides on a Sabre 30. Perhaps a tad over kill for some, but the owner wanted to be able to reef the main from the cockpit. He reports being able to exactly that. In order to achieve this for him I had to rework a chunk of the reefing system on the boat. All done remotely-He In Michigan & me in Newport.

Ronstan ball slides on a Sabre 30. Perhaps a tad over kill for some, but the owner wanted to be able to reef the main from the cockpit. In order to do that, incorporating all the inherent friction from such a reefing arrangement he needed a low friction solution at the luff. In order to achieve this for him I had to rework a chunk of the reefing system on the boat. All done remotely-He In Michigan & me in Newport. A particular advantage of the Ballslide system is the ability to simply remove the sail from the mast with out worrying about the carriage carriers. In fairness most of the Ball bearing systems with track now do this too but not having to install a track is something many find attractive.

 

 

This image does not do justice to the Selden system. On the other hand since you need a new spar tube, it is not the most marketable system. The cars operate INSIDE the spar in a cavity extruded into the spar and are introduced through the black fitting seen here.

This image does not do justice to the Selden system. On the other hand since you need a new spar tube, it is not the most marketable system. The cars operate INSIDE the spar in a cavity extruded into the spar and are introduced through the black fitting seen here.

CARS/SLIDES: WITH ball bearings:

HARKEN: It will be no surprise that most people’s first thoughts turn to Harken, at least in the US, when the phrases “boat gear” and “ball bearings” are used in the same sentence. The brothers Harken have cars and sliders, ball bearing and not, plus the required track for every size of boat from small, like a J-32 to 90 feet and/or 140 sq. meters, about 1500 sq. feet.

A very typical combination of Harken ball bearing car with a Battslide box.

A very typical combination of Harken ball bearing car with a Battslide box. The Battslide box shown here has been superseded by a later generation with improvements on how to get the batten in and tensioning details. Battslide boxes are manufactured by Schaefer.

RONSTAN: In some quarters, perhaps expats, like me, familiar with Australian sailing equipment, recognize the Ronstan name too. Like Harken, Ronstan has track and car systems for boats as as small as 40 FEET up to 45 METERS.To be fair to Harken, they too offer custom solutions for boats over 90 feet

This is a one combination of the Ronstan equipment

This is a one combination of the Ronstan equipment. The sticker says Frederickson because that was the name of the company before Ronstan purchased them a few years ago.

FACNOR: Followers of French boats would recognize the Facnor name in reference to headsail roller furling and not associate them with roller bearing mainsail luff track hardware. The Facnor equipment is nicely made and revolves around one track size, with the cars getting progressively bigger for larger sail/boat applications. They offer systems suitable for sails up to 130 square meters.or roughly 1,400 square feet.

Facnor track car toggle/Stud with a Sailman box.

Facnor track car toggle/Stud with a Sailman box. The track size stays the same but the cars get progressively bigger for bigger loads.

 

SELDEN: offers a hybrid in their MDS system. This however requires a new spar tube since the Selden cars run inside a special cavity extruded into the tube, so rather impractical unless you are getting a new mast or boat as in fact this owner was doing-A Saga 43 in this case. Selden also has a track and ball bearing system called RCB in two sizes. Selden calibrates the correct equipment based on the boat’s displacement. This system is interesting because it has a novel way of easily disconnecting the sail from the cars, the latter thus stay on the spar.

These four all use a dedicated track.

TRACK ATTACHMENT: There are four ways to attach the track to the spar. Either fasten the track to the spar with the appropriate sized metal thread fasteners. Use the connection slugs offered by the equipment maker, slide the tack into the mast groove-Tides and Dutchman or glue it on, for Carbon  spar applications

RONSTAN: has a cross over product called a Ballslide that has recirculating ball bearings in the car and a variety of screw-in shapes they call “feet” that will, at least in my experience, fit any mast groove one is likely to find. This is one of the hybrid products.

RUTGERSON: Another hybrid slider with ball bearings, albeit really small ones, is from a long established Swedish sailing hardware firm called Rutgerson. Their products are distributed in the US by Challenge Sail cloth, another supplier of sail making bits and pieces to the trade. The Rutgerson cars/sliders look like a beach or moon buggy and the bearings are in the wheels of the buggy.

DUTCHMAN SYSTEMS: From the folks who brought you The Dutchman flaking system, is their entry in the luff track stakes. The Dutchman has two versions. A dedicated track option and a track-less roller bearing cars option. The later has a similar “Beach Buggy” looking batten slider, see below.

CARS/SLIDES WITHOUT ball bearings:

BAINBRIDGE- ALLSLIP: At the simple end of the spectrum there are “regular” luff slides that can operate in the masts own luff groove and do not need a dedicated track. The most common slides one step up from merely using the slide the sailmaker would use regardless of whether the sail had FLB or not, are called Allslip Slides. They are marketed in the US through Bainbridge, one of the main suppliers to sailmakers of the nuts and bolts of every-day sail making as well sailcloth. Allslip slides are made from a low friction plastic, not nylon as the bulk of the rest of the luff slides are.

A Bainbridge Allslip slide with a stud to a PNP batten box.

A Bainbridge Allslip slide with a stud to a PNP batten box. When using Allslips, there needs a toggle with a slightly different front end, where it connects to the handle on the slider.Regardless of the connection to the slider the box connection will use an M10 or M12 thread.

Bainbridge also offers their own integrated FB line they call Sailman. Sailman consists of a range of slides, toggles and boxes for three varying sizes of boat or sail area.  The toggles they use in the Sailman can also be used with the Allslip slides. This feature works particularly well with Selden spars whose luff groove profiles are unique to their mast sections.

TIDES TRACK: A company based in Florida called Tides Marine, that is in the slippery plastic business, offers a high value product.  This is an extruded low friction plastic that comes rolled up in a spool, like a garden hose thus minimizing shipping costs. The requisite number and type of slides go to the sail maker. The track mates to your existing mast track, particulars of which are determined by a set of templates they send you or their dealers have. Propriety stainless steel slides that work only in their track (and others slides do not…) are available in three sizes of height: Intermediate, batten or reef slides and head slides. They are roughly 1”, 2” and 3” tall respectively.  Tides offer their own batten “boxes” aka receptacles but these are leech loading only.

DUTCHMAN SYSTEMS: The ever enterprising Martin Van Breems is also in this arena with two products. One is similar to the Ronstan Ball slide and the other is a track system product similar to Tides System using a low friction plastic proprietary extruded track and dedicated sliders. The Ball slide version incorporates small SS balls in wheels that run on the outside of the spar’s groove to accept the compression from the FLB and look largely like the Rutgerson moon buggy design.

The main difference between the Dutchman dedicated track version and Tides product is the Tides slides run INSIDE their track and the Dutchman system runs on the OUTSIDE of their track. The second important difference is the Dutchman track system hardware is unique to Dutchman.Thus no other cars or sliders will fit on the track and they do not have the ability to use third party toggles or batten boxes.

ANTAL: is a prominent Italian manufacturer of all sorts of sailboat hardware hardware. They have a dedicated track with slider system. These sliders have a low friction fiber composite insert. Antal also has roller bearing cars at the upper end of their range. They too come in a variety of sizes suitable for smaller boats up to 100 feet. They offer their own propriety batten boxes. Their batten sliders come with the virtual industry standard 10 mm and 12 mm threaded studs.

SCHAEFER MARINE: also has an offering in this non-ball bearing field. They have a selection of “normal” sliders, toggle connectors and the very widely used original Battslide batten boxes. They also have a dedicated track one can install but I have never seen the advantage of this unless the spars extruded track is damaged in some way. They offer a wide cross section of sliders to fit probably all mast sections built in the US in the past 50 years, With and with out “rigid” toggles, but attached by shackles to the slider. Thus their products is frequently seen on smaller boats where the proportional cost of Full Length battens and related hardware is a bigger percentage than on a larger boat.

 

Next up: The Battens followed by “all the things you didn”t know, you didn’t know…

 

 

 

 

Full Length Battens-3: Square Head mainsails

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The Square Head Mainsail–on to advantage side of the equation:

The Square Head mainsail is the default style for the Class 40 short handed offshore race boats.

The Square Head mainsail is the default style for the Class 40 short handed offshore race boats. Don Miller Photography image

The previous few essays have focused on the limiting issues surrounding full length battens including, for the vast majority of the normal boats that most of us sail, the backstay.

Briefly I have proposed that:

  • There is not really solid empirical evidence that one sail with FLB is faster than the SAME sail with leech battens on the same class of boat and assuming that both boats are prepared to be as identical as possible.
  • The Cost of FLB may outweigh the Value a lot of the time
  • I will get to the “sail handling” aspect of FLB further along in the series. This area is in fact one of the areas that does offer increased value for the owner via ease of handling the sail: Hoisting lowering reefing.

For now I am going to concentrate on the most obvious advantage and a much lesser known aspect of full battens in general and the Square Top mainsail in particular.

In my experience virtually all discussions with sailors regarding sail shape is one sided, in that it revolves around the sail’s shape and so the implied concept is aerodynamic lift. I cannot immediately recall any discussion where the other side of the lift equation is even mentioned let alone discussed: DRAG.

Drag is everywhere on a sail boat:

Someone with more time on their hands than me could calculate the amount of drag on this boat

Someone with more time on their hands than me could calculate the amount of drag on this boat

The actual hull topsides

Cabin profile

Rigging

The sail’s surface

The width of the roller furler or furled headsail when sailing with a staysail

The furling drum

The anchor

Rails, life lines stanchions

The dinghy stowed on the bow or in Davits

Cruising boats carry lots of kit and it is all drag.

Cruising boats carry lots of kit and it is all drag.

Halyards

Dodger

Life raft on the cabin top

Bimini

People standing up- This is why most good race boats have the guys all sitting together in breeze or laying low in light air.

Radar either tower astern or on mast

Radar reflectors…..You get the picture.

What is missing from this list?

It is one of the reasons why the square head sail has emerged over the past few years.

We have discussed the usual limiting factor for the size of the roach on most boats is the backstay, closely followed by adherence to a handicap racing rule.

Enter the “open” class boats, in particular the solo offshore race boats. This cohort encompasses the Mini 650 class, the older open 40’s and the much more successful, as a class, Class 40’s, the open 50 and 60 foot mono-hulls and their multi-hulled cousins and in some parts of the world open class skiffs like the Aussie 18 footers.

None of these classes (I am not 100% certain about the 18’s) have any restrictions of sail size or shape, only number and type depending on the individual class and the race.

If Bigger (more area) is Better, so the square top sail is born.

The one element missing in this discussion so far is the mast.

The mast, the square top sail and full length battens are all interconnected.

 The Twitter version:

The mast is drag

The square top sail minimizes that drag

The ST cannot work without full length battens

ESPECIALLY in this case, the FLB need a low friction track because of the great compression generated by the ST sail.

The NPR version:

Because it is sticking up in the air, the mast is 100% drag, at least for the purposes of this essay-Ignore the wing masts and wing sails please.

Over the span (the fore and aft width of the sail-the girth.) the drag from the mast is reduced because the air is smoothed out by flowing across the sail.

As the sail ascends into the air on 99% of boats it gets narrower, again almost universally due to tradition as manifest in the backstay.

This image gives a good visual of the issue at hand-Namely the top 3-4 feet of mainisail-on a 40 footer-is not contributing to reducing the drag from the mast.

This image gives a good visual of the issue at hand-Namely the top 3-4 feet of mainsail-on a 40 footer-is not contributing to reducing the drag from the mast.

At a point that varies for all sorts of reasons this reduction in drag is reduced. The drag from the mast starts to increase.

The point is that usually within a few feet of the top of the spar and for a rule of thumb it can be where the girth of the sail is less than about 4 or 5 times the local for and aft length of the mast, the amount of drag over comes the amount of lift generated by the sail.

For instance, let’s say the mast is 6 inches fore and aft. 4 or 5 times 6 inches is 24-30 inches. So in this example the drag starts to increase, dramatically, at that point on the sail where the girth is less than 24-30 inches wide fore and aft because there is not enough girth in the sail to smooth out the turbulence created by the wind hitting the mast.

This image shows the ration of the mast for and aft length to the width (girth) of the sail as the sail approaches the mast head. 4 or 5 to 1 puts the equal girth n this main at a little lower than half the distance between the mail head and the top batten. I enlarged the image and used a metric rule against the screen to determine this.

This beam on image shows the ratio of the mast’s fore and aft length to the width (girth) of the sail. This is obviously a conventional mainsail and was built to comply with local racing handicaps. As on almost all conventional yachts, as the sail approaches the mast head the position of the girth on the sail diminishes. On this Sabre’s main the girth equal to 4-5 times the masts span is a little lower than half the distance between the mainsail head and the top batten. Functionally then the (mast) drag starts to increase dramatically somewhere above the top batten is. I enlarged the image and used a metric rule against the screen to determine this.

Enter the Square Head sail. This sail profile minimizes the drag from the spar as well as being much more sail area.

I do not have many images close up of the relationship between the mast width and the sail girth as for the one of the Sabre above, but I think you get the idea.

I do not have many close up images of the relationship between the mast width and the sail girth as for the one of the Sabre above this image, but I think you get the idea. This image courtesy of Don Miller.

BUT

It is functionally impractical for any boat with a backstay. Unless of course you want to lower the mainsail every time you tack which may sound like a pain but again find out what the customer is trying to do with his boat sail goals plans etc. I did do two offshore cruising boat sails that were exactly that big roach that would not clear the standing backstay. In one case, the image below, it was a bit difficult to get through in light air although he reefed in about 14 knots of wind, so the roach was easier to deal with the first reef in. I did another offshore cruising mainsail where the owner specified that he would sail with the first reef in if lots of tacking was going to be involved. The roach in this sail was even more aggressive than the first one.

This is the roach profile of the first boat I mentioned in the paragraph aobove.

This is the roach profile of the first boat I mentioned in the paragraph above. Many thanks to the owner for providing the image. www.mccubbin.ca/boat

 

This particular boat was built with two configurations-One with this large roach and NO backstay at all for coastal cruising in and around New England. The spar was of course so designed. And a smaller main WITH backstay for going in the ocean. This is one way to do it...

This particular boat that I did the working sails for was built with two configurations-One with this large roach and NO backstay at all for coastal cruising in and around New England. The two light lines you see on the sail are more conventional runners for headstay tension, but are not really required to keep the rig in the boat. The spar was of course so designed. And a smaller main WITH backstay for going in the ocean. This is one way to do it. Boat was a custom Bruce King design.

For boats with such sails, very large roach OR square head, enter the twin topmast running backstays, generally referred to as “the runners”.

As the name implies, they are running backstays that attach to the masthead and are adjusted by a two or three part purchase led to a winch.

This image gives a bit of an idea on the twin running backstays idea. Yes, this is a race boat, a single handed forty footer from the 2009 O.S.T.A.R

This image gives a bit of an idea on the twin running backstays idea. Yes, this is a race boat, a single handed forty footer from the 2009 O.S.T.A.R. The two padeyes with blocks on the transom are part of the three part purchase this boat has. The blue cordage crossing forward of the starboard stern rail is the last fall prior going to the winch through a clutch at the very edge of the image. The pair of blocks adjacent to the base of radar plinth are for the mainsheet.

Upon contemplation it will be seen that this is not something to be undertaken lightly. Many things need to be contemplated, not the least of which, in no particular order are:

Boat & Deck hardware lay out

Mast strength

Standing rigging configuration

The degree of sweep of the spreaders

The skill of the operators and

Their willingness to put up with this added task when tacking

All these factors contribute to the reason why most “cruising” boats do not have square head sails.

Next up running backstays, batten compression and hardware for the battens.

Our first sail late in the afternoon. Scott Bradford assisting and checking the spar.

This is my mini-650 on her first sail late in the afternoon in August 1995. Scott Bradford assisting and checking the spar. This was the first 5 minutes of sailing after her launch. At the time this roach profile was considered to be huge. If you look at the luff you will see the luff sliders I used-NOT ball-bearing at all, but the best available option on the day. I was more interested in keeping the sail on the boat during handling.

 

Full Length Battens-2c: To FB, or not to FB

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With apologies to you know who.

I have received another question and a related comment  from some readers on the LinkedIn forum “Sailing Network”. This  forum requires authorization but the  access is free once registered.

The question comes from Pippa who appears to be either the principal or a partner and is a RYA Yachtmaster Instructor (Sail) with Miramar Sailing School, Antigua

“I’ve been reading your comments and blog about Fully Battened Mainsails – I have a Jeanneau Sun Odyssey 40 which has sails that are probably the originals from 1996. The main is starting to look ‘tired’ and we have been considering getting a new sail with only leech battens – do you think this would be a retrograde step, or not make a significant difference to her performance? Obviously the current main being a bit out of shape won’t help, but will we regret not getting a replacement that is fully battened? Interested in your opinions!”

This is the comment from the same forum from a reader in San Francisco, DG Tilton-

“Get the full battens. I got about half a knot better in low winds. Most importantly, for students, better control in a jibe. The extra expense of new batten cars/slides for the mast was well worth the investment. The command of out haul for shape also improved performance as well. The difference between old and new is always an increase in speed. But the performance of my sail in 12 years is like new. I teach heavy weather sailing in SF Bay. Our typical winds of 25 kts to 35kt present dynamic conditions due to micro cells of wind vortex. Your lighter winds in Antigua make sail shape even more important. The difference is like releasing more energy for speed instead of drag.”

This is interesting because both correspondents seem to be in the sailing instruction business and both seem to sail in conditions of more than enough wind, most of the time.

I will point out here I am not writing to advocate for or against full battens. Each boat, owner, situation, skill and experience level, sailing plans and a sea-bag full of other factors influence any decision on a boat and the decision on FLB’s is no different.

These essays are to share what I have learned over a more than 15 years as a sailmaker sales rep. that is incorporated into over 50 years of sailing including roughly 40 in the marine trade.

As I read through the question and comment i received, I have the following questions for Pippa centered on her basic question to me:

Would getting a sail with FLB be a retrograde step OR make a significant difference to her performance?

Then the first thing is to go back to the first essay and review the discussion there in particular the part about performance increases after either:

Adding FLB to an old sail. Second is getting a NEW sail with FLB.

My question at the beginning of the first essay is:

Can the “increased performance” be attributed to the Full Battens, on the new sail

OR

Does the “increased performance” stem from the fact that the sail is new and so has all the advantages of a new sail?

These include of course a new(er) shape, perhaps “better” (more stretch resistant-even Dacron) materials than the old one, perhaps larger area via more roach, I note that OEM sails are notoriously “small” with regard to roach and the materials used in such sails are not so great, a superior shape design if from a different sailmakeing firm and or designer or simply what has been learned over the intervening years since that sail was designed.

I am not aware of truly empirical evidence that full length battens on THE SAME SAIL, ON THE SAME (class of) BOAT improve the PERFORMANCE of the boat. And how are we defining performance? Faster, higher or both?

Issues to consider when trying to answer that question include:

  • Does a FLB mainsail make the boat so equipped sail faster and or higher-compared to the “old” sail with out FLB?.
  • In what wind speed?
  • In what sea conditions,
  • Steered by whom?
  • With or without a prepared and smooth bottom?
  • With the same amount of stuff, in the same place in the interior?
  • With the same headsail, in the same “shape” condition as when the old main was being used?
  • Same rig setting?, rake, backstay, mast prebend cap shroud tension?
  • Same weight on the rail?
  • Same helmsman?

These all play a part in a boat’s “performance” and are some of the particulars that sailmakers want to have in place before even consenting to go on a sail speed trial. Organizing and executing such testing with two boats is a right royal tedious business too,even at the top end of the sport and is full lots of small details that are very hard to uncover. For instance I once did a sail for a fellow with a free standing cat rig spar. After delivery he called to complain that he could not keep up with some of the boats at the rally/rendezvous he was attending. After about 6 hours of sailing, questioning, measuring, reviewing details of the design, I discovered that this fellow had a mast step that was in totally different place than other boats I had measured on the dock adjacent to him and that his spar was, for reasons unknown it was larger in diameter…..He did not even know it was larger.

I can attest from my own experiences that determining if one sail is faster (and or higher) than another is a very long drawn out process. This experience comes from two America’s Cup campaigns and lots of hours sailing along in a straight line with lots of smart and experienced sailors and sailmakers trying to make the boat go as fast as it can, then changing nothing else except the sail in question and repeating.

Thus even with an identical Sun Odyssey prepared as closely as possible to Pippa’s boat in order to be as equal when sailing along side each other; there are still many variables to be incorporated before the “increased performance” of the sail can be attributed to the sail having Full Length Battens.

Read again my remarks in an earlier post as to why,” if FLB are faster”, why then does the J105 class not all have FLB mainsails for instance? The 105’s have no rules regarding batten length. The paragraph is about half way down the post.

The next part of a decision to incorporate FLB into a new sail has to do with, as I wrote in the first essay,  value and encompasses things like:

  • Extra cost for the (addition of the) battens on the sail.
  • Issues of moving FLB around by carrier if necessary. Long, and skinny is expensive to ship even if it light in weight. I am thinking, Spares.
  • What are you going to use for luff hardware, at what cost and thus value? In my going for the cheaper option is not sound. This is especially so on a 40 footer, used (I am assuming) as an instruction boat with the attendant minimal seamanship (as distinct from hours or miles of sailing) experience of the students, one assumes, in an area with more than enough wind most of the time.
  • Considerations of maintenance, specifically chafe: The Sun Odyssey 40 has spreaders with some amount of sweep to them. When running down wind the battens, especially the top couple will bear on the standing rigging and chafe due to the hard spot where battens in the sail cross the standing rigging. The chafe will be harder than a sail with conventional battens.
  • The mechanism for securing the sails into the pockets-Perhaps not a great issue on a boat that may not stray far from home. Regardless reefing any sailing 25-30 knots of wind always flogs the sail and invites battens to spear out the leech end.
  • Stowing the sail on the boom. Here is one area that the FLB are or can be superior and perhaps add the value but only if combined with a slippery track arrangement and some kind of sail containment. The SO 40’s I looked at on the web all have some kind of boom bag and lazy jacks for the sail to be captured by and stowed in. Again more money.
  • The battens and pockets, cars and batten boxes all add weight. I have memories of a mainsail for a 40 footer weighting 50-60 lbs. Add another 15 pounds for all “the stuff” if the sail has a really low friction track and car system.
  • The added weight of the track and the now heavier sail all sticking up in the air will have an effect of some magnitude on the boats stability. Whether or not it is visible to the human eye depends on other variables.

I am not going to recommend or not FLB. As I say above my goal is to lay out what I see as the issues that by experience many folks do not consider in their interest in and experience with FLB.

In sum the question for Pippa to contemplate is:

“Is all this worth the extra capital cost and the maintenance cost compared to the Value you get from them?”

Value being subjective but of course including performance (it will be a new sail after all), possible increase in ease of handling the sail-if appropriate sail capture kit is incorporated into the boat, additional weight to hoist, a less “aggressive” flogging” of the sail when it is not trimmed. This is because the battens slow up the frequency of the individual flaps, to and fro that are the components parts of flogging.

Pippa, you asked for my opinion, well here it is (grins) Mr. Tilton says that  the “extra cost” is worth it but that is a decision you will have to make for yourself and your own circumstances.

Were I consulting with Pippa on this sail in my previous life, these would be the questions I would be putting to her.

 

Full Length Battens: 2b. In mast furling

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A reader on LinkedIn posted a response-comment-observation regarding FLB and conventional battens  with respect to in-mast furling so I will add this essay as a small side bar. My apologies I do not have many pictures for this subject, so you will have to read it, not look at it…

The question posed by this fellow is this:

And then there is the roller furling main! New experience for me as I have always sailed a traditional main (with battens). Very difficult to get used to looking at my main with the foot not fixed to the boom. My sail does have battens but the one nearest the head had to be removed to allow for the sail to be completely furled within the mast. I have been told that battens are not really needed in the furling main but started showing up because there was a “demand” for them. i like to convenience, especially when single handling, but………..would appreciate comments.

First a bit of background/History:

Most of us know that the original in-mast furling was invented and brought to market by Ted Hood, sometime in maybe the early 1970’s. They were unique at the time, had the Hood Cache and were almost the default spar on a long list of various sized Little Harbor yachts and then later other yachts particularly bigger ones, up to 80 footers which were big then.

Compared to the current crop of in mast furling spars, the Hood spars were really easy to work with from a sailmaker’s perspective. Not the least because they were designed by a sailmaker rather than a mast maker. There are two primary reasons related to this ease: The cavity into which the sail rolled was large.  Second, the slot through which the sail passed was wide, perhaps an inch or more. Boat for boat both these items were larger than the same parts on spars today.

Between the time of the Hood Spars introduction and the early/mid 1980’s Hood was the 800 Lb Gorilla: There was Hood Sailmakers and Hood Yacht Systems with the latter incorporating the Sto-Away masts and later on an in-boom furling arrangement  for a time plus the Hood Sea Furl furler, another virtual monopoly-No Harken, Profurl, Schaefer, Facnor, Furlex. There were a couple of older makes of furling (not reefing) head stays, one by Hyde and another by Stearns but they were not designed for using the headsail reefed. There was a particular part of the Hood Sea Furl Systems that made this viable. Regardless, if you wanted an in mast furling spar you went to Ted.

But things change. Hood sailmakers was sold in 1986, which is when I went to work for the new owner but Ted kept Hood Yacht Systems and brought it with him from Marblehead/Little harbor to Melville in Portsmouth RI.

Over time other mast makers began copying the Hood Spar, but of course they needed to be among other things, cheaper than the original (Hood Spar) in order to get a foot in the door. Anyway we now fast forward to the 21’st. C. Hood Yacht Spars was sold to the UK distributor of Hood Spars who sold it to another UK spar company who eventually went broke. Hood Yacht SYSTEMS, largely the furler’s, remains in business based in Florida and is a division of POMPANETTE. Roughly parallel with this progression many spar makers who used to do production aluminum spars have switched over to carbon and so today there are three remaining heavy weights in the production aluminum spar (In–mast furling) business:

Z spars, Charleston Spars/SparCraft both French and Selden, Swedish.

And on the edges of the In-mast terrain there are, or used to be, a couple of products you can bolt on to the back of the existing spar and some folks have taken a normal headsail furler and attached that to their spar with custom parts.

With respect to the sentence in the fellows remarks above, on “demand”, sailmakers (and cloth guys too) are forever trying to do something that will set them apart from other sailmakers. Battens, full and leech, for in-mast furling sails is a classic example of this. I am pretty sure that a Hood Franchise in Sweden invented both the batten idea and the necessary mechanics and sail designs to make it all work. Hood in the US marketed them as Vertech Mainsails and promoted, as does every one, the idea of more roach as opposed to the standard battenless sto-main with leech hollow, like a headsail.

Very broadly speaking, as viewed from my perch at Hood Sails for 15 years, there has been since the 1980’s an increase in people coming to sailing who did not grow up with it and so have a different seamanship background than say my generation who was sailing from age naught. Thus people buying boats (as well as a lot of others) were attracted to the idea of doing everything from the cockpit, so the in-mast furler’s, are now more common again than for a while. Without doubt the ability to “get the sail out and be sailing in one minute” or variations on same are pitch’s that do not quite fill the air at boat shows but is close.

Remember though there are two primary differences between the present in-mast spars and the original Hood Spars and they are the internal diameter of the cavity-Where the sail rolls up and the width of the slot through which the sail enters and leaves this cavity.

For all sorts of reasons the newer masts are smaller on the inside and the slot is much narrower than a Hood spar. Since the customer has a specific boat with a specific mast sailmakers are obliged to come up with ways of making their sails fit what the owner has, at a price they can sell them for while making money and having them work with sufficient success that the owner can use it, maybe enjoy it and so may return for other sails.

So, to the sails:

There are three flavors of in-mast furling mainsails: No battens, partial battens and full length battens. The latter are inserted vertically into the sail from the foot. These battens are usually in sections so they can be connected in some way. The ones we used at Hood, screwed together with custom fabricated terminals. The length of the sections, at least in the US, is determined by the maximum length UPS will carry so they can be shipped economically compared to shipping”regular” of FLB by truck.

With regard to sails, we know that the corners of a sail are reinforced with layers of fabric, the so called corner patches. The bigger the sail the larger, in area, are the patches. They are also thicker-more layers of material laid into the corner. This latter issue has a direct impact on the process of getting the sail in and out of the spar. The short answer is that for the current range of production spars the patches need to be thinner than they should be. This has a direct impact on the life, the shape retention life, of a sail because the corners distribute the loads into the body of the sail, less distribution surface, more load.

This thickness issues plays out with battens too. Let me first mention a couple of points about battens. As a general rule a batten’s length ought to be long enough so that 1/3 is “outside” the straight line between head and clew and 2/3 are inside. So the “inner” 2/3 is holding the outer third in place. This gets to be more critical the larger the roach-Hence full length battens in the first place.

This batten length calculus is relatively easy to meet in a conventional mainsail. It becomes a bit trickier with an in-mast sail. This is because when the batten is vertical, the batten needs to be a lot longer overall, in order to meet the desired ratio of batten inside versus outside the straight line. When the batten is longer it needs to be stiffer to achieve the desired effect. Given a same material, say polyester fiberglass, a pretty common material for battens, then a stiffer batten is thicker than a batten doing the same job on a conventional sail which will be shorter.

Still with me?

Then there is the batten pocket: It adds thickness to the sail. Typically the batten pocket is a couple of layers of material of the same weight as the sail’s cloth.  The pocket has a pleat in it so the there is volume inside the pocket to accept the batten and there is some kind of mechanism to keep the batten in the sail. Velcro is a favorite these days as are folded over flaps with lashings as well. This construction is often as thick, or thicker, than the corners AND it is on the leech so all the battens, all four or five of them must be able to roll inside the mast….

All of the above is of course at reasonable hazard of chafe. The pockets where they go in and out of the slot. The sail skin itself is liable to chafe when being rolled in or out in any condition apart from head to wind. The chafe issue applies to all flavors of in-mast furling sails: plain or with battens. On the full battens, where the connections are, they are a tad wider than the neighboring batten material so when the sail is passing the edges of the slot, there is chafe at each of the perhaps dozen or so connections.

Re-read the remark in the original question above where the owner had to have the top batten removed so the sail would get into the spar. This means I hope that the attending sailmaker had to re-fair the leech too otherwise the “local roach” at that batten would either wave around in the wind or be pulled into a curl by the leech line. Any way I digress…

Now connect the particulars of a sail so designed and built with the newer masts with smaller cavities and narrow slots. The end result is that sailmakers need to make the sails “thinner” in order to fit into the spar. Plus the batten’s are thicker and there is added thickness for the batten pocket assembly.On more than one occasion a prospect was unable to purchase a battened in-mast sail for his boat, at least from us, because when I looked into the particulars of the mast he had and the boat (so I could spec. the sail appropriately) comparing the width of the slot to the thickness of the battens and related structure, there was barely enough wiggle room and this was without the sail skin or the pockets.  I can recall one spar I was looking at, from one of three makers cited above and the slot was quoted as being only 16 mm wide, perhaps 9/16″. The battens, the pocket and sail was close to 12 or 13 mm.

The same problems or issues occur too with full length vertical battens only there is the additional complication of having to install the battens in the sail with the sail fully unrolled. Think about this for a minute…Would you willingly unroll (or hoist) your mainsail at the dock in the marina and let it flap around for the time it took to get the battens in? Perhaps not. This drill is required though with the full length battens in order to get the batten (s) into the sail. For instance on a Little Harbor 46 footer with in fact a Hood Spar, so it was actually pretty easy to operate the sail once the battens were in the sail, it would take me 45 minutes to an hour to assemble the battens get the sail into the spar and the battens into the sail. And it could only be done either on a calm morning or with only a light air wafting across the boat from the direction in which the bow was pointed.

All of this would make one think that the in mast furling system is not possible to manufacture and sell which is patented not the case. Rather I am presenting some of the issues that go on behind the curtain. For the sail these are:

Thinner or lighter base material, smaller patching both in area and in total weight in the patch and thinner battens and/ or pockets.

So, I hope this has offered some food for thought as well as a bit of a glance around “behind the curtain” into what goes on in the minds of, and discussions of, sail makers, their reps and designers.

I’ll get back to “regular” full length battens-soon.

Full length Battens-2a: Girths

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Here is a bit more detail concerning the girths mentioned in Full Length Battens:-1.

As noted in Full Battens:-1, the Girth is the distance across a sail from the “same” points the luff and leech.

A quick glossary:

Girths: the distance across a sail from a POINT on the luff to the corresponding POINT the leech.

Point: the spot on the luff and leech of a sail corresponding to one of the following: 25, 50, 75 or 875. percent up from the foot. You need two  points to get a girth

Girths are universally described as: (Reading up from the foot of the sail)

MGL–Mainsail Girth Lower: The girth at the bottom 25% POINTS

MGM–Mainsail Girth Middle–the width at the 50% POINTS

MGU–Mid Girth Upper–the girth at the 75% POINTS

MGT–Mainsail Girth Top–the girth at 87.5% POINTS

The most common way to start measuring  the girths on your mainsail is to lay it out flat on the ground.

Lay the sail out flat on the ground.

Lay the sail out flat on the ground.

This exercise works better with two or three people, in fact for race boat programs, modest ones where not every one knows everything….. it is a nice little team building exercise for the winter. You can measure all of the sails so every one on board has an idea of what sizes the sails are. In this case though I used a screw driver pushed through the cunningham eye into the grass.

Secure the tack with, in this case, a screwdriver pressed into the soil.

Secure the tack with, in this case, a screwdriver pressed into the soil.

Take the head of the sail and fold it down to the tack. Jiggle the luff so that the top and bottom of the sail are straight like folding a sheet or towel and make a mark where the fold is. This is the MGM luff POINT

Fold the sail so the head comes down to where the tack is.

Fold the sail so the head comes down to where the tack is.

Make sure the two corners, the head and tack and then the head and clew are even.

The corners of the head and the tack need to be overlapped on top of each other.

The corners of the head and the tack need to be overlapped on top of each other.

Mark the fold in the sail with a pencil, a regular #2 is fine.

Make a pencil mark on the sail under the fold.

Make a pencil mark on the sail under the fold.

If you merely want the MGM, fold the head over to the clew, straighten out the leech and mark where the fold is on the leech.

Next take the head over to the clew and lign the corners up as for the tack.

Next take the head over to the clew and line up the corners as for the tack.

At this point, you can if you wish unfold the sail and lay a tape across the sail between the luff point and the leech point. You now have the Mainsail Mid Girth, MGM or 50% girth usually spoken as  “the mid girth.” As a practical matter when measuring sails it is better to mark all the points along one edge first then do all the corresponding points on the other edge.

The MGM is measured from the mid point luff to mid point leech.

The MGM is measured from the mid point luff to mid point leech.

To get the 3/4 and .875 girths, fold the head back to the MGM point as shown below.The picture below shows the 75% girth position on the leech. When you measure the 75% girth point(s) on the luff and leech you can measure across the sail and you now have your 75% girth or MGU, Mainsail Upper Girth.

With the sail folded in its original half, fold the head back so that the head meets the MGM fold. This determines the 3/4 girth, MGU

With the sail folded in its original half, fold the head back so that the head meets the MGM fold. This determines the 3/4 girth, MGU

 

By continuing to fold the sail back and forth, you can also get the .875% girth too, as necessary

Fold the sail back one more time to  get the .875% girth too, as necessary

From the 75% fold, fold the head back one more time to get the .875% point, as necessary. If you do the same drill with first the tack and then the clew folded to the half way fold you will get the dimension for the MGL, Mainsail Girth Lower.

It takes all of 15-20 minutes, to do this from pulling the sail out of the bag to getting it back into the bag and recording the dimensions but this does depend on the size of the sail, where you are doing it and how many people are involved.

Remember that to meet MOST racing rating rules the girths must meet the lengths equal to the percentage of the foot as outlined in Full Battens-2 Scroll down about half way.

Sailmakers use all of  this information regardless of what kind of mainsail they are designing. For cruising boats, you and the sailmaker need this information in order to make the sail so it does not overlap the backstay too much UNLESS this is something you have discussed with them.[ See here: Scroll down to the bottom two images]. It is necessary too for in boom mainsails because these booms are very precise on how much roach a sail can have-Too much and it will not roll properly. The roller booms come with a 30 (or so)  page manual for the sailmakers. With the advent of battens for in-mast sails girths come into play too. For race sails, even for Wednesday night racing, of course you want the sail to be legal.

If you are taking the measurements off the boat yourself one thing they may ask for is the distance from the gooseneck, aft and parallel with the boom, to the backstay.  In other words the position on the backstay where the boom would intersect the backstay ( if it was that long) If this distance does not have its own check box in the measuring form, make a note in the “comments” section of the form. These dimensions give the sail designer a triangle that outlines the area in which the sail might fit, unless you have come to terms with them for something else-Like a oversized roach. In other words a triangle with sides: Luff, the distance from head to boom/backstay intersect AND distance boom /backstay intersect. With this information the sail designer can place the backstay on the design software and so know where the girths are going to be relative to the backstay.

One last detail regarding girths….

Girths can obviously have an impact on how much ROACH a sail has, BUT remember that the sail designer needs to take into account mast bend too. Sails have shaping in the luff and on a mainsail it is generally called luff ROUND, or sometimes positive, because it protrudes forward. The opposite is hollow, or negative.

In this picture of the Laser sail, you can see the luff ROUND outside the straight line between the head and tack.

luf curve 1

The relationship between ROACH and LUFF ROUND varies depending on many things but boat type, rig type, fractional Vs. masthead, degree of mast bend on either are some of the main ones. At the end of the day, the girths are one of the variables a sailmaker uses when determining how to design a sail and they have an impact on the sails roach. And the roach has an impact on whether or not the sail needs, or requires full length battens and if so what kind of sliders and related hardware is desirable.

These measuring protocols are the same for head sails and spinnakers. Remember this when we get to Code zeros in a while.