Mainsail, full battens vs open leach ?

[Wotname]

I would like to hear from people who have experience with full battened mainsails and/or with open leach (battenless) mainsails.

I am about to get a new mainsail and I THINK I want roachless main; the sailmakers I have spoken to all believe I should get a fully battened main.

My limited experience (only 4000nm of bluewater) has been with short battened mains. I know the pro and cons of short battens. I believe I understand the theoretical pros and cons of full battens and no battens but have zero experience with either.

My concerns with full battens is a perceived problems in depowering the sail, hoisting and lowering the sail, reefing, chafe (batten pockets), cost (as well as not being able to afford batt cars or similar).

The sailmakers contacted so far tell me I will loose to much performace and loose sail shape to quickly with an open leach main.

Main is about 220 sq ft, I will be passage making (cruising not racing, short / single handed) about the bottom of Australia (under down under!) - can get a bit breezy here - on a 31 ft LOA mast head sloop. Existing main has short battens and a small amount of roach.

Please share your thoughts, comments and especially experiences of these sails.

[Charlie]

I think that you need to look at your sale plan as a whole. On my 41' sailboat we have two full battons on the top and regular battons on the top. I like this arrangement b/c it does not neccesitate (sp?) any batton cars. If I had my choice I would have my boat powered similar to a J105 with a 100% jib and a large main. As is I do that on my boat but in light air it would like to have more sail area. When it comes time for a new main I will look at getting an extension on my boom of a foot or two.

I have never sailed on a boat that was a battonless design. but I did forget to bring my battons one say on a little 22' sloop that I owned. The sail did not hold good shape at all.

The only other thing I can think of would be the early roller furling systems for the mast where no battons are avaialble. They were said to suffer from lack of performance.

[svTOTEM]

As a former sailmaker, I agree with what the sailmakers you mention say about performance loss and poor shape. Do a search on mainsail or battens and you should find other posts on this subject.

I propose a slightly different solution. Make the top 2 battens full length and the bottom 2 battens parallel to the foot but only 50% to 70% across the sail. You can even make the bottom 2 battens the same length as the longest full length batten to reduce/simplify the spares issue.

A short list of the benefits is: less cost then using all full battens, dampens flogging, no loss in prformance, top 2 full battens are still short and don't hinder the raising lowering, bottom 2 less then full length battens distribute the load across the sail and do not suffer compression breaking when reefing, your mainsail will last longer.

As for the 2 full batten end fittings, ask your sailmaker if they have any used ones (we always did) that you can buy for cheap. Another way to save a little is ask for a sewn ring at the head, instead of an aluminum headboard. The loss of sail area is insignificant, it weighs less, and is easier on folding.

Hope that helps.

[Sandero]

I am into my 3rd mainsail in 21 years with a fair amount of offshore sailing. First sail was 4 standard battens in the leech and then 4 full length battens for the ext two sails. The 2nd sail was very heavy with the intent to sail offshore. The present sail is lighter Vektron with lighter battens, but improved cars. I have used a Dutchman for all.

I am happy with full battens because of the no slatting and improved sail shape. The sail is large (440 SF) and so raising it IS a bit of a problem, but slab reefing is not, especially with the Dutchman and reefing lines led aft.

I recommend full length battens, but get a decent cars for them.

[GordMay]

Cruising Sails: Mainsails ~ By Carol Hasse
http://www.porttownsendsails.com/pdf/mainsails.pdf

A Battenless Mainsail is sometimes called a Roachless Main. Battenless mains can be particularly efficacious on low-aspect rigs.

An Open Leach is a light wind sail shape; wherein the traveler is trimmed to windward of the centerline, and the mainsheet is eased so that the end of the boom sits to lee of centerline.
The outhaul is eased, and the backstay, and cunningham are completely loose.

An advantage of battenless sails that is not often discussed, probably because relatively few people care about it, is that you can raise the sail with the wind coming from any direction, there is nothing to get caught on shrouds, spreaders or lazyjacks.

This is, of course, most important to those who sail without engines, or those who plan to sail without engines.

Sails with partial battens can be raised while sailing on a close reach under headsail alone.

With full batten sails, in my experience, you really need to be powering into the wind to raise (or drop) the sail.

How important this is to you will depend on your sailing philosophy, engine age and reliability, and planned cruising grounds.

I have sailed boats with full batten sails, partial batten sails, and unbattened sails. I find it difficult to believe that a full batten sail is more cost effective for the long distance cruiser than a unbattened sail. There is, however, no question that it will move the boat better in many, or even most, conditions. How much better depends on the boat. Do you have room for a lot of extra roach? How important is the main in supplying light air drive to the boat? Extra roach can also affect helm balance in some designs, for good or ill. There is never a simple answer.

My own choice for long term self-sufficiency and economy under sail is an unbattened main. I am a bit unusual in modern sailors in that I consider my engine a luxury, not a nessesity. I will rig nothing on my boat that would require a functioning engine for the mobiliy or safety of the boat. For short range coastal cruising my choice would be rather different.

Certainly full battened sails are better for the sailmaker's and rigger's wallet.

[Wotname]

Thanks everyone, have some food for thought. I hadn't considered svTOTEM's idea of full upper and partial lower battens.
GreatKetch's philosophy on engines matchs mine. Although I have a brand new 2GM20 with plenty of power for the boat size, it's purpose is always auxiliary power and I sail on the understanding it might not work at any given time.
I guess I was afraid that going to an roachless main might be a poor choice given one rarely sees them around the clubs and in my experience, the sailmakers talk them down. It is good to hear of some cruising people are using them. Maybe I will remeasure my existing short battened main and see how much area will really be lost if the leech is opened by say 8 per cent.
BTW, light air performace is not high on my list of essentials. I can always crank up the donk if I really DO need to get somewhere. Ease of reefing and general heavy weather handling is more important to me, especially when short (or single) handed on any passage over a couple of days.

[Sandero]

I neglected to note that we have a fractional rig, so the main is doing most of the work. On a masthead rig the main may not be as critical to driving the boat.

[S/V Antares]

I have a full battened main with Lazy Jacks. Other than being a bit sensitive to wind dead on the bow for hoistng I think it is a great system,. I am a cruiser but like good sail shape. Properly tapperd full battens work well for me.

[DockH]

I am not aware of any mainsail longevity studies but my full battened main has provided service far beyond my expectations and I am a bit picky about performance. I haveJ Jiffy Reefing and the battens fall easily into the Lazy Jack to make sail handling to a minimum when dousing the main. Raising the main can be tricky until the shortest battens are raised past the Lazy Jack rigging.
I will get a new main this Spring, full batten for sure. PS: I have a couple of sets of battens each set tapered to fit the expected sailing conditions.

[chris95040]

This thread is ancient, btw.

I was speaking with a fella with a sister ship and he was telling me to consider a fully battened main. I thought that was 'performance gear' and was surprised he found it useful on our old tubs. Furthermore, I wondered how you depower a sail like that when the draft is being enforced by the battens?

He told me that to him it had a very practical benefit as an aging cruiser. By having a more stable sail shape, he could depower simply by trimming to more aggressive angles that would have caused his previous main to luff. Curious if anyone has an opinion on that.

[double u]

...had a batten- & roachless main on our wharram years ago - never looked like it was setting well....never had a battenless main again; for a lot of deepreaching (tradewind rtw) fullbattens don't seem to me to be the thing to have...