In-Mast Furling on Cats - Pros & Cons . . .

[colemj]

I think a workable sail can be made for a boom furler - it's the mast furler sail requirements that cause the problem on a cat.

Someone mentioned the howling noise from wind blowing over the slot of a mast furler mast. I forgot about that point. This isn't really a problem at anchor because the boat will point into the wind and be quiet. But we spent a night anchored just off a dock once that had a boat with mast furling tied up to it. The wind was at an angle to the boat and the mast slot made such a cacophony that we prayed that a boat with an Air-X windgen would anchor next to us to drown it out!

Mark

[simonmd]

I've noticed that many designs of cats don't have their boom at 90deg to the mast, this would make both kind of furling difficult to set up properly.

[muskoka]

In-mast furling is a system bought by people fairly new to sailing. Experienced sailors aren't neutral on in-mast furling: They hate it.

It kills performance, adds weight and cost. All for a very marginal level of convenience which can be otherwise achieved without the bad side effects.

For this reason it'll also have a negative impact on the resale value of the boat.

[SailFastTri]

In addition to all the other arguments, this is a safety issue.

The critical scenario is explained in detail in my first post in this forum on the topic of "The proverbial "Line of Death"
http://www.cruisersforum.com/forums/...tml#post138314 (More than 470 posts later, here we are again...)

If a large (e.g. cruising) multihull is not equipped with low-friction track and full-batten main with battcars it cannot reef downwind -- nor recover from being overpowered in a downwind situation, when wind force is building.

In-mast furling mains can't be furled while powered-up downwind. Therefore they are unsuitable and potentially dangerous equipment for a multihull.

[Factor]

I dont get roller furling on mains. I have roller bearing batt cars and full battens and a bag and lazy jacks. It goes up very easy and comes down easier, On any sort of distance we stow the bag and the lazy jacks. Its cheap and simple. I can reef off the wind.

So I just dont get them, but too each his/her own I suppose.

[goboatingnow]

I'd like to add my tuppence . Good well maintained in masts system like all gear rarely give any trouble. The vast majority of jams are caused by too little clew tension on furling and this generally results in not being able to get the sail out rather then in the other thing that few sailers understand is the processes involved to unjam an in mast. ( probably because they rarely jam) .

Yes everyone accepts that battened sails are more efficient, but in most cases properly designed in mast sails are more then adequate . If this was an efficiency argument we'd all be using rigids

In my opinion having owned both battened single line reefing system and in mast, there's a lot to be said for in mast. Ive have lots of problems with battens and if was to buy another conventional sail, I'd avoid full battens . I've yet to be on a conventional production boat where single line reefing doesn't require a trip to the mast to ensure the sail is ok and this means that one man watches are problematic especially art night. Where's on in masts it rarely requires it.

It's entirely possible to reef in masts downwind. Went across the Atlantic on and in mast and we had no problem reefing at 150 degrees. ( reckmann in mast)

Modern materials have also removed the sail weight issue and there are also a number of systems for supporting a small roach as well ( I like the air battens idea)

To say that experienced sailers avoid them is quite wrong. amels, ovnis oysters , HRs etc are all bought by experienced sailers and lots are sold with in mast.

The other thing is far less string in the cockpit. Especially as in my view modern main driven boats ( and this applies to cats) need three reefs in the main to control the speed ( this is particulary true of modern French production boats). And this results in more string. The best reefing is double line reefing but now there's six pieces of string not to mention all the clutches. In fact a fully car based three reef main system is probably more expensive then in mast.

I really think dogmatic opinions are best ignored. Each system has pros and cons. Go with whatever suits you

Dave

[Cotemar]

goboatingnow,

Very well said. I am with you on Furling Mains. I believe they will be coming online in the next few years, because cruisers really want them. Most cat owners have come from monohull sailing and furling mains. They want the same convenience on there cruising cat.

Mark

[SailFastTri]

Originally Posted by goboatingnow

It's entirely possible to reef in masts downwind. Went across the Atlantic on and in mast and we had no problem reefing at 150 degrees. ( reckmann in mast)


Dave

Is this true even when the boat is being overpowered? I'm very skeptical, as the loads would be huge and the friction of the mast being pushed (and bent) around the slot edge would be quite significant. Please describe how this is achieved.

BTW -- I have no doubt you could furl it under light load. There can be a big difference between reefing and furling circumstance.

[simonmd]

Originally Posted by goboatingnow

It's entirely possible to reef in masts downwind. Went across the Atlantic on and in mast and we had no problem reefing at 150 degrees. ( reckmann in mast)

Yes, I thought so as well. Part of my sailing tuition was on a Bavaria 37 with IMF and we had to put some reef in as the wind started getting up while we were practicing jibing, ie, deffinately downwind.

We just pulled the boom to near center, slackened off the halyard, winched in the sail, slackened it a bit more, winched in a bit more, etc. until we were happy with it. No hassle and not once did either of us have to get on the roof to attend to the sail first hand.

Having said that, as a future single handed sailor, I think i'd be more comfortable with a standard set up as there's less to go wrong.

[stacy]

Jennius, thanks for the info. We have manual winches on the mast and I was thinking of tying a line to the luff cringle O ring at each reef and pull it down if necessary. I hadn't thought of using one line to the top bat car. I will try that

[mdsilvers]

I agree Jennius that is sounds like a good idea for a downhaul. I will look into the top bat car. Thanks for the tip!

[tsmwebb]

Originally Posted by goboatingnow

I'd like to add my tuppence . Good well maintained in masts system like all gear rarely give any trouble. The vast majority of jams are caused by too little clew tension on furling and this generally results in not being able to get the sail out rather then in the other thing that few sailers understand is the processes involved to unjam an in mast. ( probably because they rarely jam) .

Nice post Dave. I like your philosophy. However, I'm not sure I totally grok two points you're making. It seems to me that too little clew tension when furling will result in a loose roll that can fill the mast and jam before the sail is completely furled. I have seen this happen. I expect this happens most often when the crew is in a rush and that seems like the worst possible time. I've also seen problems with mis-cut and imperfectly installed sails jamming. I've also seen a bushing on a top swivel disintegrate and result in a bad jam. And, as mentioned before, I've got some friends who managed to get a their top shackle jammed in the slot. I'm not a rigger or anything, these are just problems I've come across in passing. Your point that folks don't understand how to unjam the sails when they do jam doesn't comfort me somehow. Now, it seems to me that virtually all of these problems are caused by having the roller system inside the mast. So, please help me out, what are the benefits of in-the-mast-roller-furling versus behind the mast? I've tried and I can't think of any serious benefits of in the mast furling over behind the mast. I suspect that people chose in the mast because it looks nicer. But the cost in potentially serious problems seems like a high price to pay for style. I'm sure I'm missing some important benefits. What are they?

Tom.

[Factor]

Originally Posted by goboatingnow

.... I've yet to be on a conventional production boat where single line reefing doesn't require a trip to the mast to ensure the sail is ok ...Dave

Dave - I reef without leaving the cockpit. Its a production boat.

[Mark Johnson]

I would seriously consider a roller furling boom instead. I have Australian friends with a 32' cat, who went around the world with theirs, and it made the trip a safe experience. (doable for folks over 60)

It was factory set-up, and that was the ONLY way they sold it. (Factory installed)... It had to be an excellent installation to be problem free, but theirs worked perfectly for their 10 year trip.

They have many advantages:

like, lowering the weight of the sail as you reef, when you REALLY need less weight aloft.

They are MUCH easier and less expensive to retrofit, later in the boat's life.

They don't whistle in the wind.

They allow for a full batten, large roach mainsail.

They are infinitely reefable.

They keep a good shape as you reef.

And every adjustment, including closing the sun cover, is just a matter of pulling some lines, or cranking a winch. There is a minimum of effort and deck work.

If I could only afford it...

Mark

[muskoka]

I've sailed on a boat with in-mast furling for a few seasons. I don't find the issues related to jamming to be much of a concern as you can quickly figure out the techniques to get the sail furled with a bit of experience. Though you couldn't reef downwind in a serious blow.

Ask any sailmaker for their opinion. The key failing lies in the poor cut of the sail: There is no roach, no battens, the fabric needs to be lighter which leads to a shorter lifespan, the draft is usually not optimal and you really can't fine tune the sail. A mainsail provides the majority of the power in a cat.

Stating that in-mast furling has an inferior sail isn't a dogmatic opinion: It's a fact based upon the physics governing sail performance. You need to weigh that against the marginal convenience gained when furling the sail.