400: Square top mainsail

[arsenelupiga]

My L 400 logged 18K NM and started thinking about new mainsail.

I currently have normal sail - not top square, and quite like it.

What are people's experiences with square tops ?

From my experience, one loses ability to 'tack' boom lift line which is extremely handy in sub 10 kn winds. This may cancel benefit of extra 5m2 sail area ?

Also top batten - does it damage sail track, can imagine forces are significant, especially when 'automatic' reefing happens, reefed or not.

I asked sailmaker and he said top square is really appropriate for costal sailing only, not open ocean. Presume top square more prone to locking sail up there and cant be taken down ?



thanks in advance for your answers.

[Stumble]

I am a big proponent of square top sails. It isn't just that they are bigger which helps light air sailing, they also are more efficient, which further helps light air sailing. Basically you increase the available power at the same time you decrease drag, so it's a really positive thing from a sailing standpoint.

But there are tradeoffs.

1) you will need to get rid of the topping lift on the boom and move to a rigid vang. But I would do this anyway, topping lifts are a royal pain in my book, and shorten sail life. Their minimal benefit in some conditions just isn't worth it to me.

2) baton preassure can make them a little sticky coming down. It's resolvable with better slides. It's really the same issue as a fully battened sail just with one additional full length baton.

3) it can be a bit of a pain to put away the top baton. There is hardware to make this easier, but it to is expensive.

4) because the top baton will open in gusts, they basically have an automatic reef built in. The sail actively trims itself to spill power in gusts then returns to shape for steady preassure. This makes them easier to trim, and helps keep the boat from being overpowered.


Basically if you are fine with your boats performance I would just keep what you have, but if you want to increase performance, particularly light air performance it is a very good upgrade.

As for your sail maker... I think you need a new one. Anyone who suggests they shouldn't be used offshore is just wrong. There is a reason every single offshore race boat built in 20 years has used them.

[tuskie]

We have a L400 with a factory original square top main. Probably most examples of this model have this sail. I haven't sailed on a L400 with a non- squaretop sail, so it's difficult to compare.

I agree with most of Greg's points, especially about eating animals.

I've never seen a Lagoon 400 fitted with a squaretop and a vang. It may be an improvement over the topping lift but I doubt that the factory rig would easily be modified to take a vang. A topping lift can be a pain with any roachy main; catching the leech end of the battens when raising this sail. Once the main is up, it's not such a problem and can be used to assist in shaping the sail.

Another benefit of having a topping lift is that it can double as an emergency main halyard. We shattered the attachment block on our 2 to 1 main halyard and were glad to have the topping lift as a replacement option to going up the mast in rather large seas.

In short, we have no adverse experience with the square top main and would view it as an improvement over a standard main sail.

[meirriba]

Originally Posted by Stumble

I am a big proponent of square top sails. It isn't just that they are bigger which helps light air sailing, they also are more efficient, which further helps light air sailing. Basically you increase the available power at the same time you decrease drag, so it's a really positive thing from a sailing standpoint.

But there are tradeoffs.

1) you will need to get rid of the topping lift on the boom and move to a rigid vang. But I would do this anyway, topping lifts are a royal pain in my book, and shorten sail life. Their minimal benefit in some conditions just isn't worth it to me.
.

Two questions:
1. Why the need to get rid of the topping lift? We are sailing for 6 years now, around 12,000 miles with a square top AND topping lift line. No problems incurred.
2. Vang on L400 - did you see one installed? I would be happy to add a rigid vang. When the boat was new I have tried to investigate such amendment but the mast manufacturer threatened me with end of warranty if a vang will be installed.

[meirriba]

One comment on square tops: the top batten tends to catch on lazy pack lines during the process of sail raising. Needs careful course keeping into the wind and/or someone on cabin top to free the lazypack lines.

[UNCIVILIZED]

I'm with Stumble on this. Especially the bit where every racing boat without a fixed backstay has such a main, probably for a reason. And there are plenty of cruising boats where they're standard equipment.

As to vangs, on some boats you have to go with one that's "inverted". But such designs are long since proven. And I far prefer a vang to a topping lift. You can still have a spare main halyard, but whatever you choose to call it, it's not a substitute for a good vang.

The reason you don't see vangs on some racing multi's is only because they have semi-circular traveler tracks, so that the main sheet can pull directly downwards on the main through most of the boom's arc of rotation. And even then some boats have them, as they're more than a little handy when it comes to trim.

[meirriba]

The vang would be highly beneficial however the OP refers to Lagoon400. The distance between cabintop and boom is very short and seems that fitting a vang is impossible.
I would love to see a proper vang installed on a L400 to copy.

[UNCIVILIZED]

Originally Posted by meirriba

The vang would be highly beneficial however the OP refers to Lagoon400. The distance between cabintop and boom is very short and seems that fitting a vang is impossible.
I would love to see a proper vang installed on a L400 to copy.

Ergo my mention of installing an inverted vang. They're common in several one design fleets, as well as some custom boats. Such as the one on Bruce Schwab's old boat, Ocean Planet, as seen here https://xpda.com/junkmail/junk181/oc...t/P1050332.jpg

[Delancey]

Ocean Planet

[44'cruisingcat]

I have a square top with a topping lift, and no problem. I have the topping lift adjusted a bit loose, so the boom angles down slightly, and under sail it's always loose.

IMO the square top is a worthwhile improvement, extremely easy to trim.

. I can easily reach our headboard, so there's very little hassle in stowing or deployment. I just unpin the headboard from the headboard car.

[UNCIVILIZED]

In one of the Lagoon threads or another, there are discussions on how to make the upper batten on a square top main automatically self-raising, & self-lowering, when hoisting the sail. It involves a precisely measured length of Spectra attached to one of the batten cars acting as part of a lever during the hoist & drop, to properly position the batten which holds the top edge of the main horizontal. That way one needn’t climb up onto the cabin top, or perhaps even the mast, in order to setup the main for a hoist, or when putting it to bed. And included in one of the threads on this is a video as to how it works. However, I don’t recall which specific thread it’s in. Perhaps someone else knows? That or a search may turn it up.

[Stumble]

Originally Posted by meirriba

Two questions:
1. Why the need to get rid of the topping lift? We are sailing for 6 years now, around 12,000 miles with a square top AND topping lift line. No problems incurred. They can work, obviously, but topping lifts on square headed sails have a long and glorious history of causing damage to the baton pockets of the sail. If the topping lift is only used when the sail is down and pulled forward when the sail is raised it isn't an issue. But even on large roach sails topping lifts can be damaging.
2. Vang on L400 - did you see one installed? I would be happy to add a rigid vang. When the boat was new I have tried to investigate such amendment but the mast manufacturer threatened me with end of warranty if a vang will be installed.I haven't, and after looking at pictures of a L400 I doubt you could attach a vang if you wanted to.

What Uncivilized is talking about is called a G-Nav btw. They do the same job as a vang just in reverse. But I would be hesitant about retrofitting one. They can place a lot of load on the lower third of masts and can often require jumper stays to control mast bend right where the gnav attaches. It's one of those mods I would want a manufacturer to give their input on before doing.

[django37]

Have sailed 25000 nm with this main, no problem. Squaretop is 6'

[meirriba]

Originally Posted by UNCIVILIZED

In one of the Lagoon threads or another, there are discussions on how to make the upper batten on a square top main automatically self-raising, & self-lowering, when hoisting the sail. It involves a precisely measured length of Spectra attached to one of the batten cars acting as part of a lever during the hoist & drop, to properly position the batten which holds the top edge of the main horizontal. That way one needn’t climb up onto the cabin top, or perhaps even the mast, in order to setup the main for a hoist, or when putting it to bed. And included in one of the threads on this is a video as to how it works. However, I don’t recall which specific thread it’s in. Perhaps someone else knows? That or a search may turn it up.

The spectra line is part of the original square-top installation by Lagoon. We have it on our boat. However, while giving the top of the sail its proper shape while raised, it does not help much during the sail raising excercise. We usually end with someone of agile legs climbing up to help until the top batten clears the lines.

[arsenelupiga]

thanks for your opinions.

Clearly will consider it. Original lagoon option for square top upgrade was quoted at 250 euros, so I presume that means mast & tracks are already built to handle square top.

Is it realistic to tack on longer sail legs by taking in one reef in main, 'tack' topping line and shake reef ?

This would minimise batten pockets damage and still have wang simulation ability ?