How Much Roach?

[A30_John]

I took the fully battened main that came with my boat to the sail loft the other day and mentioned I was thinking about having some of the roach cut off. I had been finding it difficult to balance the helm, and thought the boat was too difficult to handle during the gusts.

A couple of guys at the loft unrolled the sail on the floor, and stood there aghast at what they saw. Without saying a word, one guy ran off and got a tape measure and they measured the roach at 26". Neither of them had ever seen a sail for a monohull with that much roach. They said 10-12" was "normal." They looked in their database and found an A30 main they made a few years ago and that was manufactured with 5" of roach.

I'm going to get a new main and either sell the old one or keep it as a spare. Does anybody have any experience with various mainsails on A30s, Tritons, etc. that can offer insights into the appropriate amount of roach for these boats. I love the old sail in the light winds and I can easily get speeds of 6.5 - 6.8 k in a moderate breeze. I don't want to sacrifice too much of that speed, so still favor a "full roach" sail, but I also want to balance the helm and have a more manageable boat.

All advice is appreciated!

[Tim]

26"!!! Wow. That's a huge amount of roach.

I don't know what the roach is on my full-battened mainsail, but I'd guess it is closer to the 10"-12" size that might be considered normal for a fully-battened sail. The Triton sailplan drawings show that a normal mainsail's roach just about touches the backstay, which is typical on most designs; my roach rubs against the backstay near the top while tacking, so it's clearly larger than normal--but nothing like 26", which just seems absurd.

5" of roach sounds about normal for a traditional main with regular, non-full length battens. All mainsails have some roach, except those that have been cut hollow and without battens.

A 26" roach would explain a lot about your sailing problems in heavier airs, particularly how you've said that even with reefs in the sail you continue to experience serious weather helm and heel angles.

[Figment]

This really begs the question.... How did that seemingly-insane roach not get hung up on your backstay with each tack?

My short boom has me thinking of increased roach. I rarely have any more than a touch of weather helm.

Is it possible that you're a member of the short-boom club, and that a PO overcompensated with the roach?

[A30_John]

My boat has the standard (16' - I think) boom.

The overlap on the backstay is several inches.

Something else the guys at the loft said was the sail shape was wrong and the excess roach was lower on the sail than it would normally be. I'm wondering if that was done intentionally to avoid some of the problems with all that sail overlapping the backstay.

Now the big question is going to be full battens vs. regular, 10" roach or 5" on the new sail. I want good heavy weather options and I want a boat that balances well. On the other hand, the boat was a "mean machine" with that old sail when the conditions were right. It's just a matter of finding the best compromise for a wide range of conditions.

[Mark.Wilme]

If it were me I'd go with full battens every time.

[Tim]

I like full battens for most types of sailing and cruising. There are certainly situations where they are less than ideal, or at least potentially so, but those situations are mostly found in real offshore work.

I wouldn't hesitate to go offshore with a fully battened main, but if that's all I was going to do I might go for regular battens or even a hollow roach with no battens at all.

You don't need a huge roach to justify full battens. You can order a normal-sized roach and still benefit from full battens. Supporting a larger roach is sometimes an advantage, but it's not a requirement--and sometimes not an advantage.

Here are some reasons I like fully battened mains:

• 1. They do a great job maintaining the shape of a sail in light winds, heavy winds, and as the sail cloth gets older. You'll get more usable life out of a fully battened sail because of this, since the shape doesn't change nearly as much as the cloth ages.
  
  2. The mainsail doesn't slat around if you use it for stability under power on calm days, or if you have the sail up while powering into a light headwind. Quiet is good. Slatting is about the most annoying thing in the world. I happen to love this particular feature, since I always raise the main when powering.
  
  3. No hard spots at the forward end of batten pockets. This not only helps sail shape when new, and in light air, but particularly is an advantage as the sail ages. As we discovered in another thread here this fall, the leading edge of batten pockets can destroy the shape of a sail.
  
  4. The lack of those batten pocket hard spots also eliminates a common point of sailcloth chafe and wear. The hardware at the luff side of a full batten takes all the strain from the full batten, not the sailcloth.

You've already sailed with a fully battened main, so you're already familiar with what's good and what's bad about them. You pretty much need to have lazy jacks or Dutchman (which I know you have) to control the sail as it comes down; the long battens are a real pain otherwise.

I think they make the most sense in the long run, for most types of sailing and cruising. If you liked the full battens before, then order them again. If you didn't like something about them, then go with normal battens. Don't worry about what it does to the roach; you won't notice that much difference either way.

[bcooke]

the long battens are a real pain otherwise.

Yeah they are. I won't leave home without something to control those things again...

-Britton

[dasein668]

the long battens are a real pain otherwise.

Yeah they are. I won't leave home without something to control those things again...

-Britton

You'se guys are a bunch o'sissys! hehe

Yeah, they can be a bit of a pain, especially in a blow, but they aren't that bad. I've been living with them and no lazy jacks for 4 seasons and they certainly don't keep me from going out!

That said, lazy jacks or similar certainly are a nice companion to full battens.

[Tim]

I've been living with them and no lazy jacks for 4 seasons and they certainly don't keep me from going out!

That's just because you're too lazy to throw together a set of lazy jacks! :<P

[dasein668]

I've been living with them and no lazy jacks for 4 seasons and they certainly don't keep me from going out!

That's just because you're too lazy to throw together a set of lazy jacks! :<P

I fail to see your point.

;-D

[Allen]

Neither of them had ever seen a sail for a monohull with that much roach.

That's actually kind of a surprising statement. Apparently they never have watched any of the recent America's Cup events using the IACC class yachts.

[jollyboat]

OK- I will bite! I do more sidelining than posting these days but this is a thread that I gotta put my two cents in. Firstly, 26 inches of roach on an A30 does seem a little much but it all depends on how the sail was built and why. If there was 26" of roach up top you would be having a lot more trouble than weather helm and I did not read that the sail catching on the backstay is a problem. On both the Triton and the A30 more roach can be added as you go down the leach toward the clew - much more roach if you want it. Now on the sailmaking end of things - I would bet this extra roach was built into the sail at the previous owners request. Sailmakers don't just go around putting 26 inches of roach in the main because they want to. If the sail was primarily used in very light air this extra roach would be very effective, especially down wind where the A30 and the Triton suffer in performance. I have designed a sail for the Triton with just such a roach for just such reason. You can always decrease sail but it is much harder to add more area to the sail once it is built. Full battens are definitly the way to go for the A-30 - again off the wind and down wind is where they make a huge difference in sail shape. The performance over cost ratio is cheap as well.

[A30_John]

Brian, I appreciate your input, and I think you're right that the sail was intentionally designed and built that way. Moving the roach lower in the sail avoids too much overlap on the backstay, and the light air performance of the sail is very good. I'd say it was probably done this way at the request of the previous owner. The question in my mind is whether it is the best way to go on this boat. When the wind hits about 8-10k with the full main the boat lays right over and the weather helm is unbearable. So I'm off to reef. A little more increase in wind and I'm back up there putting in the second reef. On many days I just start out with one reef because I just want to relax and don't feel like fighting the boat during the gusts. It's possible that the PO only sailed in light air and therefore the custom sail worked well for his program. He did a lot of things right with that boat, and I suspect he had his eyes wide open when he ordered that particular sail.

It's interesting to note Alberg designed the A30 for lead ballast and cast iron was used by the builder instead. This put the center of gravity slightly higher than Alberg designed it and made the boat a bit more tender as a result. This may help explain why the main with all that roach lays the boat over more quickly than it might another boat. The America's cup boats shown above with all that roach were likely designed from the ground up to handle all that sail and then my guess is the builder probably built to the designer's specs.

All in all I've concluded while yes, 26" of roach makes the boat perform better downwind and in light air, the A30 may not be the best candidate for this concept. My struggle now is to figure out what is the best compromise because less sail will settle the helm down (good) it will also mean sailing slower particularly in light air (bad!). My current thinking is a full batten main with 5-10" of roach will probably give me the best result over the range of circumstances I encounter here.

[jollyboat]

A30-John,
You bring up some very interesting and important issues concerning ballast with the A30. But unless the actual weight is off considerably I do not think that the type of ballast material is main cause of the boats weather helm or heeling issues.
I have at least a 1000 pounds out of my Triton at the moment and though light on her lines I still think she would firm up at about a ten degree heel with a breeze. If your sails are full this could contribute significantly to weather helm as could not having enough headstay tension. For designs that are overall very forgiving in how they are used it is interesesting to see how if the rigs are out of tune how much it changes the characteristics of the boat. Even with the extra roach on your main the A30 should feel balanced as there is not enough added square footage in the increased area to have as dramatic an effect as has been discribed in moderte breezes. Another point is if the bottom is fouled - this really hurts performance as it steals so much inertia from the boats forward movment. The lost energy adds to the 'crabbing' effect. Try reducing your headsail area before reducing the main. Check to be sure that mast is in colum and that shrouds, fore and after guys are tensionned correctly.
Use your forward lowers to provide lower forward tention and tention the forstay by increasing the tension of the backstay. I realize that is winter now - but try these suggestions when you commission the boat this spring.

[A30_John]

Thanks for the insights Brian. I'm continuing my research into this. I've been in contact with another a30 owner who recently had a new main made with a full roach at the advice of his sailmaker. He ended up taking it back and having 5" cut off and reports that it settled his boat down and balanced the helm.

The one thing that amazes me with all this is the range of differing viewpoints with no apparent objectively "right" answer. I've had people say the "traditional" design (regular battens w/ about 5" roach as Alberg designed it) is perfect for this boat, and other say a fully battened main with more roach is the better approach in view of modern design improvements and gear, etc. I suspect it comes down to one's expectations regarding light air performance.

[jollyboat]

Well any time you include another person you are going to get another opinion. Opinions in this area are a good thing though - as long as you can muck through the fat and find some info that is useful. On the issue of battens and as a sailmaker - full battens are the way to go if you can do it. The sail design of a traditional leech batten sail and one fitted with full length batten pockets is exactly the same. The full battens allow for better shape control in a variety of situations as earlier discussed. At one time having an external track combined with full battens was bit of an issue but there have been many developments in batten recepticals that have overcome this. Balance is the real issue at hand here but I am confident that you will quickly figure it out. Once set up correctly our boats are so sweet. Not great going to weather - slow down wind - but so very very nice on a reach that it all makes it worth while. If you would like a quote on some very nice sails - please let me know.

[A30_John]

Will do, thanks Brian.