In Boom Furling experiences?

[Dockhead]

Originally Posted by beiland

. . . And I might suggest you do a bit more reading on those roachy flat-top mainsails,...they just are not proving to be that much of an advantage (if any in a number of cases), especially considering their extra handling difficulties. . . .

I don't need to read up on it because I have a fair number of actual miles with roachy mains (not flat top ones). They add a very large amount of drive. Because the sail area on the aft part of the mainsail does most of the work.

[accomplice]

Originally Posted by Dockhead

[...] roachy mains (not flat top ones). They add a very large amount of drive. Because the sail area on the aft part of the mainsail does most of the work.

Do you notice any change in the balance of the boat with a roachy main?

[Polux]

Originally Posted by Uncle Bob

And there are several saying how good leisure furl is.
Terms like brilliant and I would never go back.
If your going to quote a source at least acknowledge the comments either way.

I said to look there, not even quoted anything but the guy that said that it was crap was talking about sailing with 30k of wind. Many sailors will never sail with that wind.

He looked experienced and convincing...and it was not the only one to say that system (Leisure furl) had problems.

I don't care either way but if I was buying one I surely would want more information after several negative comments, even with positive comments.

[a64pilot]

Originally Posted by accomplice

Do you notice any change in the balance of the boat with a roachy main?

I'm not who you asked, but I did, I actually have too much main in many cases and to balance the boat I need to reef about a foot of it, or slacken the sheet a little bit. I thought going from a 110 Genoa to a 135 would fix that, but surprisingly it didn't change at all.
I guess though that perfect balance with everything out is sort of un-achievable and I'd rather have a little too much main as that's easier to deal with?

Realize I am a novice

[Dockhead]

Originally Posted by accomplice

Do you notice any change in the balance of the boat with a roachy main?

It wasn't on my boat, so I can't say - no comparison to less roachy main on the same boat.

But those boats (one of them was a chartered racer-cruiser, a Salona 45) were very well balanced.

I actually don't think that fore-aft balance of the sail plan makes much difference on modern boats with high aspect rigs and modern underbodies.

On my boat, weather helm is practically a linear function of heel angle. I sail with mainsail alone or jib alone -- i.e. no sail plan balance at all -- without problems, without lee helm or excessive weather helm, as long as the heel angle is right.

As an example -- I'm sailing hard-pressed and I've got too much helm. I drop the jib and sail on main alone. The traditional sailor in me says "WHAT? You're killing the sail balance -- you'll make the weather helm worse!"

But it doesn't. Heel angle goes down and weather helm moderates.

It took me a long time to figure this out, since it is opposite what I was taught back in the day. The light bulb finally went off in my head when I felt a lot of helm once when sailing on jib alone.

[Dockhead]

Originally Posted by a64pilot

I'm not who you asked, but I did, I actually have too much main in many cases and to balance the boat I need to reef about a foot of it, or slacken the sheet a little bit. I thought going from a 110 Genoa to a 135 would fix that, but surprisingly it didn't change at all.
I guess though that perfect balance with everything out is sort of un-achievable and I'd rather have a little too much main as that's easier to deal with?

Realize I am a novice

Try furling the headsail altogether, next time you feel too much helm. That will tell you how sail balance affects helm balance on your boat. It may be different from what you think.

[beiland]

Originally Posted by a64pilot

I don't understand, Please explain.
My boom is heavy and you have to respect it when the sail is furled, just as I assume any boom is, but with the sail up, I doubt it weighs much more than a regular boom, and its weight is negligible, way overridden by aerodynamics of the sail.
It is big though as it holds the entire sail inside of it, has to be.
But what is wrong with a full battened mainsail for cruising?

Perhaps you could have a look thru this rather extensive subject thread where in a LOT of cruising folks question the use of their mainsails,...for a variety of reasons.
http://www.cruisersforum.com/forums/...in-115978.html

[beiland]

Originally Posted by Dockhead

I don't need to read up on it because I have a fair number of actual miles with roachy mains (not flat top ones). They add a very large amount of drive. Because the sail area on the aft part of the mainsail does most of the work.

Perhaps I should not have mixed the words 'roachy' with 'flat-top', and just chosen the flat-top designation.

Several observations on these flat-tops:

Originally Posted by yeloya

I've sailed extensively with both sails on catamarans. Actually I even sailed the same cat with this two different type of sails in all kind of weather in every angle to the wind. There absolutely is NO difference ...
I am not interested in what the theory suggests but this is my conclusion after 20.000 nm of sailing on cat, both coastal and offshore.

There are a lot of difference beetween a good sail and not so good sail but a main sail is not necessarily better because the cut of its head is this or the other way..

The square head is more difficult to hoist. One needs to go to the head of the mast to hold and pull the head of the sail to attach it to the head of the sail. In most of the cases you need two people to do that in big main sails.

Durability is about the same (app. 6-7 years in charter, 20-25 weeks of charter per year)
Cheers
Yeloya

Originally Posted by davecalvert

We have been experimenting with square top mains sense the early 90s.These are now standard on any race boat that allows them. Main advantages besides the obvious extra sail area is, improved flow at the top, better twist in the upper leech, moving the power lower in the puffs, as the top twists off, and increased performance on all points of sail in the light to moderate winds.Even with the increase in sail area, these mains can often be used in as much, or more, winds before reefing than the pin head mains.I do not think these are good on cruising boats though. We design "elliptical" head mains with the same sail area but, without the diagonal, "gaff" batten. This allows the sail to be raised and lowered without the need to remove the head of the sail from the head slide assembly.The performance is about the same, at least for cruising boats.Using cross cut dacron for large square top or wide top mains is not a very good way to go. Best to use more performance materials in a triradial cut or load path constructions, for multihulls in the 40 ft and larger range.There is now a warp dacron in styles up to 12 oz. This cloth, in a triradial cut, makes a great performance cruising sail with the durability of dacron.

Originally Posted by Southern Star

I suggest that care must be taken in assessing some of the potential advantages to a flat-top main as they are not necessarily complimentary:

1. While Bash is correct that a flat-top can be used to lower the Ce of the sailplan (and lower is better for transverse stability on a cat), that is only the case if the sail area is not increased over the original big roached main - i.e., if the flat-top has the same length of luff, the Ce of the new sail will actually be higher, thereby reducing transverse stability.

2. Only if the sail area is increased as a result of the flat-top design (and the SA is correspondingly increased), will there be any real improvement in peformance off the wind.

3. Against this backdrop one must also consider the following:
- a replacement flat-top main is apt to be more expensive
- a flat-top main will be more difficult to stow and will likely require a new (and larger) boom bag
- reefing a flat-top main tends to keep the Ce of the sailplan higher unless the reef points are also adjusted downwards. While the sailmaker should take this into account in the design of the sail, it will also require a change in the attachment points on the boom for the reefed clew.

Even bearing in mind that the potential performance gains will be largely upwind, one must understand that to optimize these gains one will also be moving the Ce of the sailplan higher than the original designer intended. At the very least, this will require additional vigilence with respect to reefing.

Brad

...more here:
http://www.cruisersforum.com/forums/f48/square-top-main-vs-roachy-main-92862.html

and here:
Square top mains? - Boat Design Forums

[a64pilot]

Originally Posted by beiland

Perhaps you could have a look thru this rather extensive subject thread where in a LOT of cruising folks question the use of their mainsails,...for a variety of reasons.
http://www.cruisersforum.com/forums/...in-115978.html

The whole purpose as I understand it for a furling main sail whether in boom or in mast is to make it easier to handle.
Mine is, as long as you accept that you need to be into the wind, a small child can raise, lower or reef my main with the assistance of my Milwaukee drill.
I don't know why I have not seen them on Cats, furling booms that is, they seem to be made for one from what little I know about Cats.
I don't understand why having full battens and some significant roach would make the sail any harder to handle?

Now I freely admit that I am no racer, nor am I a seasoned and experienced sailor either, but its my understanding that a full battened main sail with significant roach is desirable, and the the biggest downside to in mast furling is you can't have it, so you get an easy to handle, but less performing sail with in mast furling, but lose significant performance?
With in boom, you get to have an easy to handle sail, and get the full battens and the roach getting some performance back, but not as much as a traditional main sail I'm sure, there are always penalties with everything.

My IP is not the Pig she is supposed to be, and her better than average performance for an IP is not due to me, I assure you, I contribute it to it having that larger sail area main with full battens as that is the only difference I can see.

[beiland]

Originally Posted by Dockhead

.....

I actually don't think that fore-aft balance of the sail plan makes much difference on modern boats with high aspect rigs and modern underbodies.

On my boat, weather helm is practically a linear function of heel angle. I sail with mainsail alone or jib alone -- i.e. no sail plan balance at all -- without problems, without lee helm or excessive weather helm, as long as the heel angle is right.

As an example -- I'm sailing hard-pressed and I've got too much helm. I drop the jib and sail on main alone. The traditional sailor in me says "WHAT? You're killing the sail balance -- you'll make the weather helm worse!"

But it doesn't. Heel angle goes down and weather helm moderates.

It took me a long time to figure this out, since it is opposite what I was taught back in the day. The light bulb finally went off in my head when I felt a lot of helm once when sailing on jib alone.

I'm having trouble understanding this as well.... it just defies force analysis
Is this a fair representation of the underwater shape of your vessel?


It appears as thought there is a significant semi-balance built into your rudder? This can add some 'powersteering effect' to your steering,...and furthermore might account for your ability to offset the sail unbalance via a set rudder unbalance that does not manifest itself in helm unbalance.

[accomplice]

Originally Posted by Dockhead

It wasn't on my boat, so I can't say - no comparison to less roachy main on the same boat.

But those boats (one of them was a chartered racer-cruiser, a Salona 45) were very well balanced.

I actually don't think that fore-aft balance of the sail plan makes much difference on modern boats with high aspect rigs and modern underbodies.

On my boat, weather helm is practically a linear function of heel angle. I sail with mainsail alone or jib alone -- i.e. no sail plan balance at all -- without problems, without lee helm or excessive weather helm, as long as the heel angle is right.

As an example -- I'm sailing hard-pressed and I've got too much helm. I drop the jib and sail on main alone. The traditional sailor in me says "WHAT? You're killing the sail balance -- you'll make the weather helm worse!"

But it doesn't. Heel angle goes down and weather helm moderates.

It took me a long time to figure this out, since it is opposite what I was taught back in the day. The light bulb finally went off in my head when I felt a lot of helm once when sailing on jib alone.

My experience is different on our boat. While obtaining lee-helm through improper trim is nearly impossible on most points of sail on her, the same cannot be said of weather helm. Although heel angle does influence the amount of weather helm, I have found balance to be largely governed by sail trim, usually such that head sail trim can reduce weather helm to a few degrees. When imbalanced, she will round up a few degrees in gusts as she heels further; when balanced the autopilot is largely unperturbed.

Since moving to a higher clew genoa, which must've moved CE aft, the bias towards weather helm is even more noticeable. My fear if I went to a roachier main is that this tendency would be exacerbated and that I would be forced to depower the main to achieve a good balance.

Sent from my SM-G930V using Cruisers Sailing Forum mobile app

[Dockhead]

Originally Posted by accomplice

My experience is different on our boat. While obtaining lee-helm through improper trim is nearly impossible on most points of sail on her, the same cannot be said of weather helm. . . .

I agree and I observe that very much on my boat as well. I should have mentioned that.

My previous comment assumed that sail trim is right, and sails are in decent shape.

Of course you can create huge weather helm by, for example, over-sheeting the mainsail on a reach.

[Dockhead]

Originally Posted by beiland

I'm having trouble understanding this as well.... it just defies force analysis
Is this a fair representation of the underwater shape of your vessel?
Attachment 136284

It appears as thought there is a significant semi-balance built into your rudder? This can add some 'powersteering effect' to your steering,...and furthermore might account for your ability to offset the sail unbalance via a set rudder unbalance that does not manifest itself in helm unbalance.

Yes, that's my boat -- the rudder is huge, and has significant balance, and that makes it easier to deal with helm -- it requires less rudder angle to produce a given amount of force, and rudder angle is generated with less steering force.

But otherwise, no -- there is still little effect on helm balance just from moving CE of the sail plan around. How and why I couldn't say, but there it is. I can sail on full mainsail alone and without any headsail at all, and there is very little difference in helm balance.

There are effects of underbody and keel shape at play which are beyond my technical knowledge. Also I believe that the high aspect ratio of the sailplan compared to the boats I grew up with reduces the effect of movement of the CE.

[Polux]

Furling booms have been replacing in mas furlers on big yachts, specially when money is not a problem. They offer the advantage of a better sail shape, the possibility of lowering the main on the case of a jam and don't worsen the boat stability when it is more needed, in bad weather with the sail heavily reefed.

That tendency is arriving to smaller yachts and there are some that are already proposing a furling boom as an option, not to a furling mast but to a three line system (in the boom) to reef traditional way.

I think it is interesting that this year Sail magazine Yacht of the year (over 50ft) is just a 50ft boat that offers that option and the boat tested had it:

Funny also that what some call (in my opinion wrongly) a med boat had won the trophy in America after having won the European boat of the year on its class, last year in Europe.

They say about the boat:
"The sleek, low-profile deck dressed in acres of unblemished teak set behind a no-nonsense plumb bow is reminiscent of a luxurious Wally Yacht mixed with perhaps a touch of Nautor’s Swan. What’s more, our judges found the Solaris offers substance as well as style.

For example, while the Solaris is a close-winded performance boat with a powerful rig, the easy-to-handle controls, thoughtfully laid out, allow a couple or an adept solo sailor to manage the boat with a minimum of drama. Similarly, although it makes a minimalist fashion statement, it has some nice cruising features, including a hidden liferaft locker, a hide-away bimini frame that can support a fully enclosed deck shelter when deployed, and a very usable dinghy garage hidden behind a fold-down transom; all of which makes it user-friendly and quite livable. In spite of the space given up to the dinghy garage and a large sail locker forward ...Finally, our judges were impressed with the boat’s finish quality, especially given its aggressive price point, which in turn allows the boat to embody what the builder describes as a kind of “accessible luxury” at its best. "

A favorite of mine too, impressive by the price, finish, sail ability, seaworthiness, storage..and for a dinghy garage, quite rare on that size. The design of the hull makes it also a surprisingly dry boat even with strong wind. Take a look after the middle of the movie and look also how good look that boom furler:

https://www.youtube.com/watch?v=rD44kb8fLGo

[SSgtPitt]

I have the Leisurefurl Offshore setup on my CD36. It's a tank. I like being able to furl from the cockpit and the powered winch makes a HUGE difference. The sail is extremely difficult to raise by hand. I've adjusted and lubed everything but it hasn't gotten any easier.
The downhaul is how you adjust tension in the sail, not with the halyard.
The statement about it being a "telephone pole" is accurate. These things are stout pieces of equipment and while any boom will knock you senseless, this one is bigger and heavier. I gybed accidently and destroyed my car and traveler. It was also 34 years old, so needed an upgrade. Some type of limiter should be a mandatory consideration.
If the boom is not set at the right angle, the sail will ride forward when furling and bind against the mast.
Too little tension on the opposing line when raising or lowering can cause the furling line to bind around the drum. I've only had this boat a year so I'm not an expert yet, but the powered winch will snap the furling line quite easily if you're not focused on what you're doing.
I can reef at any point and at any wind angle, but it's MUCH easier to point up a little. I haven't done it at 30+kts but I did do it at 25kts.
Like anything else, the more bells and whistles you have the more things you'll need to maintain and the more complicated it becomes.
Read the attached file for info on how to setup, maintain and operate the Leisurefurl system