In-mast vs in-boom furling

[LoudMusic]

Originally Posted by a64pilot

See, my guess is not ever having sailed a Cat that they get the majority of their propulsion from the main, where my boat is head sail driven.
If that’s correct then a Cat won’t do anything to decrease main sail performance as that would kill sailing performance, so no in mast or in boom.
However, and I’m not beating on Cats, but that may partially explain why they seem to often motor, if they aren’t going far, and raising and putting away the main is a lot of work, then they just won’t do it, it’s not worth it. I wouldn’t either.
In boom and I assume in mast is dead easy. Yes I turn into the wind, but furling is simply holding onto a Milwaukee drill until the sail is completely in the boom. If we are staying overnight, then you disconnect the Halyard of course, if not then don’t quite furl completely and leave some of the sail in the track and raising it is just holding that Milwaukee drill again.
Want to reef? Just a few seconds of the drill to roll up as much sail as you desire, you have an infinite number of reefing points and don’t leave the cockpit.
You only leave the cockpit to connect / disconnect the Halyard and to start the sail in the track.

There are two of us, but in truth I’m single handing. She helps of course, but she isn’t into sailing

I think that catamarans typically do produce a significant portion of their power from their main. But like monohulls it's going to be different on every design.

In the highly unscientific testing I've done on my Orana, in winds where I can make 1.5 to 2 kts with just the jib we'll make 4.5 to 5 kts on just the main, and 6+ with both.

Exactly as you mention, motoring because a default for trips under a couple hours because #^% messing with the main.

However, I don't think the power loss from a boom furler would outweigh the frequency of use due to the ease of a boom furler.

As I mentioned in an earlier reply, I'm very interested in it for my catamaran but holy crap they're expensive.

I just did some googling.

https://www.sailmagazine.com/multihu...on-a-multihull

[saillr]

I am 80 years old and use the in boom furling all the time. A few years ago I sailed from Seattle to Mexico, Hawaii, Alaska and home. About 10,000 miles nearly all solo. The boom furling made life a breeze. So easy to reduce sail no matter if off or on the wind. Leave sail up at night knowing that reduction is just a few moments away and you do not have to go on deck.
The main difference between in mast and boom furling is if you get a jam in heavy conditions, and it is possible with either but more so with in mast, you have no choice but to cut the sail down with in mast. In boom you simply drop the halyard and lash the sail to the boom. The other reason is sail shape. In mast you are without battens. In boom you have full battens and good sail shape. Leach tension is fixed so you must control draft with halyard tension. Surprisingly effective.
The only mast furfling outfit offering full battens to my knowledge is Selden. European and expensive. They offer a vertical batten system that provides roach but I feel is not as effective as in boom horizontal battens. Also I don't like having an opening all the way up the mast. Seems to me it would have to weaken the system.

[wingssail]

Maintaining optimal mainsail shape is essential to my sailing enjoyment. Yes, we can get by with less effective sail shape (inmast furling) but we'd be griping about it all the time. So it is a choice for us. We use a normal slab reefing system.

Most of the enthusiastic sailors (racers) feel the same. Most cruisers don't care. But for us, sailing is a sport, we love to do it well. We are cruisers who are also racers and who cherish our great looking sails. For us, optimized sail shape is a big part of the game.

When I see a boat come into the harbor with windblown sailors, exhilarated by the passage they have just completed and sails all over the deck, who have just dropped their sails at the last minute before coming in so as not to loose a second of the sailing enjoyment, I talk to them they all agree that in mast furlers are not for them. But in mast furlers are ubiquitous now. A couple who are friends of our complained that they had a hard time finding a Jeanneau without inmast, but they found one and are happy. They are racers who are now cruising. Sail shape habits are hard to give up.

As for the difficulty of managing a mainsail with slab reefing or lazy jacks: it is a matter of practice. My 70yr old wife and I manage our high performance 43' sloop with a large mainsail perfectly easily. We can reef in a couple of minutes, unreefing is quicker because it is usually when the wind has dropped. Reefing is a two person job, or it is slower. We have three reef points on our cruising main. Dropping or raising the main is quick, and, we have to fold it, so we're really old fashioned.

I have not used an in-boom system but owners with them claim that they give good sailshape and are fairly easy to use.

For us, sailing is a sport, we love to do it well. For us, optimized sail shape is a big part of the game. We have no furlers.

[a64pilot]

Originally Posted by saillr

Also I don't like having an opening all the way up the mast. Seems to me it would have to weaken the system.

Of course it would, but it’s pretty easy in the design phase to calculate that and build to compensate, so that even if a little heavier, it’s just as strong. You just don’t, or I haven’t heard of mast failures without the rig going first, surely it’s rare?
Now in mast of course means more weight up high, but again as most new boats come this way, surely they are ballasted to take this higher mast CG into account.

In other words surely those things have been accounted for in the design of the mast, and boat it’s going on.

[svspirited]

My $0.02, I have in-mast on mine. When we first purchased the boat it had a very tired old main that was an absolute PITA to furl and unfurl. I also didn't really know how to use it correctly and I cursed it every time I tried to get the sail in or out. Then the main self destructed and I was forced to buy a new one. What I learned from that experience is why many people complain about the performance of them, namely they are not fully aware of how they should be set up for optimal performance.

After having Doyle build a new main for me they added a few bits and gave a bit of advice on how to make it work better.

The first was to add longer straps to the head and clew to hook into the shackles. The claim was that this will help with the initial furling back of the sail. It seems to have worked.

The second was a new clew block that spun more freely.

The third was a recommendation to move the boom car back further on the boom and allow more of the outhaul line to come out reducing the angle from the clew of the sail to the boom when furling. Also keep the track and car lubed up with a good dry lube like McLube.

The fourth was a bit of instruction on how to have the boom set before trying to unfurl the sail, namely get the boom as level as you can with the topping lift, remove all tension from the vang, and remove all tension from the furling line. This has helped considerably, before I was made aware of this there was always a bit of angle with the rear of the boom point up a bit, this messed with the angle when unfurling and made it a whole lot more difficult, always requiring the use of the winch to unfurl.

With all of that done and some new knowledge I can say that the sail is now easy to unfurl without any mechanical assistance and furling is almost as easy, though a bit trickier to keep the appropriate tension on the outhaul as you furl the sail back in.

[briblack]

with both in-mst and in-boom systems, it's at best problematic to reduce sail off the wind. you really have to get a luff in the sail to do so, and in strong conditions turning the boat across the wind can be dangerous. with in-mast, you do have to remove the mast to do some of the repair and maintenance issues. I'd go with batt cars, single- or double- line reefing, full battens, a stack-pack, sissy bars, etc.

[BenBowSirocco]

Originally Posted by Dockhead

And then there are Amels -- the only purpose-built cruising boats specifically designed for ocean crossing and long distance passage making.

Not true at all.

[billk53]

I have in-mast for 15 years I have zero problems

[Kingfisher1]

I have a factory installed Hood in-mast furler on a 1982 C&C 48. We had a new main built in about 2001 with furling horizontal battens, I believe made by Harken. The middle batten has been the only issue - the aft end of the batten is what I would term slightly lumpy and in the early days before we figured out the solution would periodically get caught in the mast groove when going from furled to opened. I learned that the sail is best furled in by always pulling on the port side furling line. It never gets caught that way - problem solved. We've had the boat for 26 years and use the main regularly both with the new main and years ago with the old one, far more regularly than if we didn't have furling. It is great! We've heard that a furling main means 15% less power from the sail due to a reduction in size of the roach, but as cruisers this is not an issue for us. It is an excellent, simple, almost zero maintenance sail handling feature on the boat. Perhaps main furling is not good for a boat where multiple people use it, little operational nuances may not be communicated to a new skipper and there could be problems.

[daletournier]

Originally Posted by saillr

I am 80 years old and use the in boom furling all the time. A few years ago I sailed from Seattle to Mexico, Hawaii, Alaska and home. About 10,000 miles nearly all solo. The boom furling made life a breeze. So easy to reduce sail no matter if off or on the wind. Leave sail up at night knowing that reduction is just a few moments away and you do not have to go on deck.
The main difference between in mast and boom furling is if you get a jam in heavy conditions, and it is possible with either but more so with in mast, you have no choice but to cut the sail down with in mast. In boom you simply drop the halyard and lash the sail to the boom. The other reason is sail shape. In mast you are without battens. In boom you have full battens and good sail shape. Leach tension is fixed so you must control draft with halyard tension. Surprisingly effective.
The only mast furfling outfit offering full battens to my knowledge is Selden. European and expensive. They offer a vertical batten system that provides roach but I feel is not as effective as in boom horizontal battens. Also I don't like having an opening all the way up the mast. Seems to me it would have to weaken the system.

An inmast furling mast is stronger,have a good look at one and you'll understand why.

[SBS]

Ive sailed for 20 years with an old LeiFurl in boom furler on my Belliure 41.
It can be a bear to hoist (Ive got a heavy Hood main...) and usually need a winch.
And both in boom and in mast are sensitive to the angle of the boom in order to furl properly.

But if theres a problem with an in boom furler you can always just drop the main like a conventional rig and tie the sail around the boom. Ive done that twice in 20 years and in a pinch its a big, and to my mind, important advantage over in mast. There are other advantages such as in boom carries the furled weight lower than in mast but being able to drop it under all conditions is the biggest one for me.

[a64pilot]

A boom furled sail can have a lot of roach, I don’t believe an in mast can though?

[waterman46]

Originally Posted by Kenomac

Having owned and used all three systems..

1. In mast furling with vertical battens is the easiest, quickest and most trouble free. Especially if hydraulic or electric.

2. In boom is nice and much better than standard stack pack, but you will need to raise the main each time it’s used, so make sure you have an electric winch.

3. Standard stack pack. Really Sucks, unless you’re a racer, masochist, purist or just plain ignorant of the two more superior methods and how to use them.

That post is a bit harsh on the good old reliable way of rigging mainsails. I am no longer a racer, and certainly never been any of those other types of persons you mention. But I found that retrofitting or replacing existing rigs to install inboom or inmast reefing is just not practical, in terms of cost. So I had a Dutchman conversion done to my mainsail. I can say without reservation that it certainly does not "suck", in fact it works great and the sail modification to full battened main is very nice.

[Medved]

Originally Posted by waterman46

That post is a bit harsh on the good old reliable way of rigging mainsails. I am no longer a racer, and certainly never been any of those other types of persons you mention. But I found that retrofitting or replacing existing rigs to install inboom or inmast reefing is just not practical, in terms of cost. So I had a Dutchman conversion done to my mainsail. I can say without reservation that it certainly does not "suck", in fact it works great and the sail modification to full battened main is very nice.

Just to clarify on my original post, I was not considering to retrofit either in-mast or in-boom. It was more about from the factory type deal one vs the other.

[a64pilot]

I’ve not seen any new boats come from the factory with in boom, there has to be a few I guess, but your really reducing which boats to look at if your after a factory in boom boat.
So that leaves in Mast, of which there are many, factory installs