Boom Furling Pros and Cons, Please

[unlvrebel]

Originally Posted by Paul Elliott

Agreed, 20% sounds unlikely. On the other hand, 0.05% isn't half of one percent, it's five percent. I've seen references to keeping the extra roach area below 10 or 12%, otherwise it starts interfering with the backstay, so 5% sounds like it could be pretty typical. Definitely not 20%.

[edit:] Actually, the loss of area could be more than 5-10%, since with the early hollow-roach mast-furling mains we are losing a few percent compared with a flat-roach sail. Still probably not 20%

Actually, 0.05% isn't one half of one percent or five percent. 0.05% is equal to five one hundreths of one percent.

0.5% = one half of one percent and 5% = five percent. HUGE differences.

[Mexdon]

Originally Posted by unlvrebel

Actually, 0.05% isn't one half of one percent or five percent. 0.05% is equal to five one hundreths of one percent.

0.5% = one half of one percent and 5% = five percent. HUGE differences.

Great first post....welcome to CF.

[minaret]

Originally Posted by bstreep

Pros: Fully battened main, easy furling, easy reefing, unlike in-mast, if it jams for some reason (never has happened to us), you can dump it on the deck.

I hear all the time that if an in-mast furler jams it's impossible to dump it on deck until the jam is cleared. This is untrue. My stock in-mast furler from 1983 came with the manual which provides concise directions on how to use the built in quick release on the bottom of the stay inside the mast to dump the main. You just pull the quick release and then pull the furled sail off the furler by pulling down on the whole roll, like taking a off a sock (exactly the term used in the manual). I tried it for practice, although I've never had a jam, and it's easy. Just so ya know...

[s/v Jedi]

Did I see cost as only negative? Here's some more:

- angle between mast and boom must be fixed at 90 degrees. This limits good part of sail trim.

- can't reef while running, have to turn into the wind.

- I've seen lots of technical problems with it, reps visiting boats to fix it etc. After warranty runs out, this costs money.

Still, I would seriously consider in-boom furling while I stay well clear of in-mast, quick release or not!

cheers,
Nick.

[minaret]

Originally Posted by s/v Jedi

Did I see cost as only negative? Here's some more:

- angle between mast and boom must be fixed at 90 degrees. This limits good part of sail trim.

This is only true while actually operating the furler, so it really doesn't have anything to do with trim. Adjust your angle however you like, just like on a normal rig, and readjust for furling if necessary. This is why a hydraulic boom vang is a must for a furling system.

- can't reef while running, have to turn into the wind.

Only true for some units, many can furl on any point of sail.

- I've seen lots of technical problems with it, reps visiting boats to fix it etc. After warranty runs out, this costs money.


Still, I would seriously consider in-boom furling while I stay well clear of in-mast, quick release or not!

cheers,
Nick.

Here we go again! I'll just throw in this link to the long argument we had on this topic, wherein the general consensus was you are just wrong on this subject. I don't know why you have such a prejudice against any sort of furling main, but you should stop spreading misinformation about them.

http://www.cruisersforum.com/forums/...t-63150-7.html

[boatman61]

Originally Posted by Bash

That's bunk. Anyone who claims to lose that much power because of a furling configuration is either a liar or a lousy sailor.

Harsh man... Harsh...who pissed on your parade....
Could just be the old style boom furl and a totally baggy sail.... actually they don't need to be that bagged... those furlers were crap...
Not everyone can afford the 'Bells'.... do we even know what type of furler he's got/seen...

[s/v Jedi]

Originally Posted by minaret

Here we go again! I'll just throw in this link to the long argument we had on this topic, wherein the general consensus was you are just wrong on this subject. I don't know why you have such a prejudice against any sort of furling main, but you should stop spreading misinformation about them.

http://www.cruisersforum.com/forums/...t-63150-7.html

Minaret,

That I give up trying to explain something, doesn't mean that what I state is wrong... it's just that you do not understand what I mean. Any, and I mean each and every one, sailmaker can tell you that I am right, as I told you before in that thread you linked. Did you ask one?

hmpfff. I'll give it another try: On monohulls you can heel and roll. Downwind when the boom is sticking outside the hull, it's possible that the boom will hit the water. The higher the waves are, the more likely this is. The higher the waves are, the more likely it is that the wind is higher too. When wind is higher, it is likely that one reefs the mainsail. When one has a good mainsail with slab reefing, the reef points will be made so that for each extra reef, the boom will be lifted up more (staggered reef points in the leech of the sail). Because the sail is cut that way, it'll be flat as a blade while the boom is lifted up. It is, in fact, lifted up by the leech of the sail. Now, if you have in-mast or in-boom furling, your main sail can NOT be cut that way. Sure you are right and you can lift the boom. But that will make your sail baggy because it is not cut like for what I describe.

Go ahead, kill me for knowing this and telling you that you do not know what I am talking about or that I am wrong. I can take it.

ciao!
Nick.

[Paul Elliott]

Originally Posted by unlvrebel

Actually, 0.05% isn't one half of one percent or five percent. 0.05% is equal to five one hundreths of one percent.

0.5% = one half of one percent and 5% = five percent. HUGE differences.

Ouch! You are of course correct. I saw 0.05% and thought 0.05 -- my mistake.

I just typed in an analysis of the PHRF mast-furling ratings hit vs various boats and their base ratings, then decided the argument/discussion would interest no one -- not even myself. So I deleted it.

[minaret]

Originally Posted by s/v Jedi

Minaret,

That I give up trying to explain something, doesn't mean that what I state is wrong... it's just that you do not understand what I mean. Any, and I mean each and every one, sailmaker can tell you that I am right, as I told you before in that thread you linked. Did you ask one?

hmpfff. I'll give it another try: On monohulls you can heel and roll. Downwind when the boom is sticking outside the hull, it's possible that the boom will hit the water. The higher the waves are, the more likely this is. The higher the waves are, the more likely it is that the wind is higher too. When wind is higher, it is likely that one reefs the mainsail. When one has a good mainsail with slab reefing, the reef points will be made so that for each extra reef, the boom will be lifted up more (staggered reef points in the leech of the sail). Because the sail is cut that way, it'll be flat as a blade while the boom is lifted up. It is, in fact, lifted up by the leech of the sail. Now, if you have in-mast or in-boom furling, your main sail can NOT be cut that way. Sure you are right and you can lift the boom. But that will make your sail baggy because it is not cut like for what I describe.

Go ahead, kill me for knowing this and telling you that you do not know what I am talking about or that I am wrong. I can take it.

ciao!
Nick.

It's you that doesn't understand. Exactly as I said when you raised this point in the other thread, it's just not true that your sail cannot be cut that way. In fact it MUST be cut with a raised foot to prevent the foot bolt rope from creating a bulge on the furler, and for the reason you mention. I just got a full new suit, and the sailmakers were impressed with the setup and thought you were nuts. Of course you can raise the boom when sailing downwind and still adjust sail trim-though I can't imagine why you'd want your main "flat as a board" as you suggest when sailing downwind.
More to the point, how does rehashing that argument address the misinformation you gave out in the post above? What you said just ain't true and you should admit it. You've said it many times before, and every time a bunch of people tell you it's not true, but you keep saying it. The boom angle does not need to be permanently fixed at 90 degrees as you say, at least not on any rig I have ever seen. And most allow furling on any point of sail. Mine does. State facts, not opinion....

[s/v Jedi]

Originally Posted by minaret

It's you that doesn't understand. Exactly as I said when you raised this point in the other thread, it's just not true that your sail cannot be cut that way. In fact it MUST be cut with a raised foot to prevent the foot bolt rope from creating a bulge on the furler, and for the reason you mention. I just got a full new suit, and the sailmakers were impressed with the setup and thought you were nuts. Of course you can raise the boom when sailing downwind and still adjust sail trim-though I can't imagine why you'd want your main "flat as a board" as you suggest when sailing downwind.
More to the point, how does rehashing that argument address the misinformation you gave out in the post above? What you said just ain't true and you should admit it. You've said it many times before, and every time a bunch of people tell you it's not true, but you keep saying it. The boom angle does not need to be permanently fixed at 90 degrees as you say, at least not on any rig I have ever seen. And most allow furling on any point of sail. Mine does. State facts, not opinion....

See, I knew you were gonna tell me that. But if you would read carefully, you would detect that some people actually understood me in that thread. If you, who don't understand it, try to explain it to a sailmaker, how can he understand it what you mean?

Now think logically... with in-mast furling, if you furl say 20% of the sail, it is part of the luff that rolls up into the mast, do you agree? Please answer so we can find out where we miscommunicate. If you agree, then explain my how that process can force the change of angle of the boom?!

But this is a thread about in-boom furling. So, if you furl partly (reef) with in-boom... you actually state that the leech gets furled more than the luff? Please, elaborate. Because that is exactly what happens with good slab reefing, the leech gets reefed further than the luff.

Flattening the sail... you don't know why? Flattening means de-powering. When you are reefing, you want to de-power.

Next your stubborn repeating that you can change the angle of your boom... Yes, I know you can, you are right, I've told you before. But when you lift the back of the boom, your sail becomes fuller. I know you do not agree with that but it really is the most basic part of sail trim. If you do agree with that, then you also understand that this is very different from putting a reef in a slab reefed main which lifts the book but maintains flat sail shape (because the leech gets reefed further than the luff). If you do not understand this, then it is my lack of English that is the problem and I just have to give up trying to explain this... but that does not make you right and me wrong.

And let me make it clear (again) that I have nothing against in-boom furling. I just point at some negatives that were left out in the discussion. I can (and did) point out negatives for slab reefing too, and many more for in-mast reefing. Every system has it's negatives and I don't understand why we just can't accept that.

As for the specifics of the different brands for in-boom furling... sure, I can understand that some are better or even fix a problem that you can have with other brands... but why does that invalidate the points I make? There are thousands who experience the problems I brought forward so the points are valid. It's very good that your system does not have those problems so why don't you explain how they solved it, which brand it is etc. That would really add to the discussion, instead of just saying no to anything I write.

ciao!
Nick.

[minaret]

Perhap's you aren't used to sailing with a free footed main, especially in a mast furler arraingment. I'll try to explain and throw in a quick sketch, with what limited ability I have.

Originally Posted by s/v Jedi

See, I knew you were gonna tell me that. But if you would read carefully, you would detect that some people actually understood me in that thread. If you, who don't understand it, try to explain it to a sailmaker, how can he understand it what you mean?

Now think logically... with in-mast furling, if you furl say 20% of the sail, it is part of the luff that rolls up into the mast, do you agree? Please answer so we can find out where we miscommunicate. If you agree, then explain my how that process can force the change of angle of the boom?!

Of course it is the luff which rolls up. But since it is a free footed main, the only point of attachment to the boom is the outhaul. So the foot of the sail is not cut parallel to the boom, but with a rise in it so the clew is higher than the tack, just like a jib. You could cut it as high as you want , just like a jib. It does not "force the change of angle of the boom" at any point, you can adjust the boom angle wherever you want, high or low, at any time, limited by the height at which you have had the clew cut and the amount of sail you have furled. The more sail you furl up, the more you could possibly raise the boom. By the time the sail is hlf furled you could raise the boom higher than you could possibly ever want to without affecting trim. Raising and lowering the boom only helps to adjust the angle at which the outhaul is pulling on the sail, although the outhaul can also be pinned on the track at any point just like a sheet track.


But this is a thread about in-boom furling. So, if you furl partly (reef) with in-boom... you actually state that the leech gets furled more than the luff? Please, elaborate. Because that is exactly what happens with good slab reefing, the leech gets reefed further than the luff.

Quote-
" Now, if you have in-mast or in-boom furling, your main sail can NOT be cut that way. Sure you are right and you can lift the boom. But that will make your sail baggy because it is not cut like for what I describe."

You weren't talking about just boom furlers, you clearly said in mast or boom furlers.

Flattening the sail... you don't know why? Flattening means de-powering. When you are reefing, you want to de-power.


A little flattening to depower is one thing, but "board flat" just seemed like an exaggeration of the desired trim.

Next your stubborn repeating that you can change the angle of your boom... Yes, I know you can, you are right, I've told you before. But when you lift the back of the boom, your sail becomes fuller. I know you do not agree with that but it really is the most basic part of sail trim. If you do agree with that, then you also understand that this is very different from putting a reef in a slab reefed main which lifts the book but maintains flat sail shape (because the leech gets reefed further than the luff). If you do not understand this, then it is my lack of English that is the problem and I just have to give up trying to explain this... but that does not make you right and me wrong.

Perhaps this is all a question of langauge barrier. I can only hope the sketch makes it clear.

And let me make it clear (again) that I have nothing against in-boom furling. I just point at some negatives that were left out in the discussion. I can (and did) point out negatives for slab reefing too, and many more for in-mast reefing. Every system has it's negatives and I don't understand why we just can't accept that.

Just don't want anyone misled about what I and many others feel is a perfectly viable system for most, and just perfect for a small group of people.



As for the specifics of the different brands for in-boom furling... sure, I can understand that some are better or even fix a problem that you can have with other brands... but why does that invalidate the points I make? There are thousands who experience the problems I brought forward so the points are valid. It's very good that your system does not have those problems so why don't you explain how they solved it, which brand it is etc. That would really add to the discussion, instead of just saying no to anything I write.

ciao!
Nick.

Mine is a Hood Stoway Electric furler. It can furl on any point of sail, furls easily and strongly in high winds, has a great manual backup system, can be dumped if jammed etc etc. And it's stock from 1983, I can't imagine they've just gone downhill since....

Please excuse the bad sketch-

[minaret]

Originally Posted by s/v Jedi

And let me make it clear (again) that I have nothing against in-boom furling. I just point at some negatives that were left out in the discussion. I can (and did) point out negatives for slab reefing too, and many more for in-mast reefing. Every system has it's negatives and I don't understand why we just can't accept that.

It's just that when you start pointing out negatives that don't actually exist, I question your level of personal experience on this particular subject, and your motives for doing so.

[s/v Jedi]

Originally Posted by minaret

Perhap's you aren't used to sailing with a free footed main, especially in a mast furler arraingment.

Yes, nice stab. Slab reefed proponents must be old salts that don't know about even loose footed sails right? Do you have any clue what kind of boat I sail at the moment?!

Mine is a Hood Stoway Electric furler.

That is in-mast furling... this thread is about in-boom, so your statements to counter my arguments do not make sense here. I still believe you can't reliably furl in-boom while sailing down-wind in anything but benign conditions.

You also ignore my specific questions so that we can't work it out (which would need to be in a thread about in-mast any way) So I will end this discussion with two photo's. The first shows a furled main with the clew atop the boom and the boom horizontal, which is very different from your writings and drawings. The second show slab reefed main where it is clear that the boom is lifted up by the reef point and this sticking up in the air like it's supposed to while the leech is tight like it is supposed to. I only post this so that readers can compare and make their own conclusions. For you, your system is perfect and I'm happy for you; I wish I was that content with all my systems But here are some real CF members that got into some of the trouble I described with their furlers, incl. your Hood system : http://www.cruisersforum.com/forums/...ues-15619.html

Oh, I'm adding another image that should help this thread become easier to understand (3rd image)







cheers,
Nick.

[unlvrebel]

Originally Posted by Mexdon

Great first post....welcome to CF.

Sorry... It's the only thing that I have had of any value to this point in time. I've been lurking in the shadows reading as much as I can...

Guess it was a little cruddy. I'll step back in the shadows again...

[Mexdon]

Originally Posted by unlvrebel

Sorry... It's the only thing that I have had of any value to this point in time. I've been lurking in the shadows reading as much as I can...

Guess it was a little cruddy. I'll step back in the shadows again...

Not at all cruddy IMHO very appropriate as we get a considerable amount of expert disinformation often based on arithmetical errors.