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johnenvanessa
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Hello - thanks for starting the discussions on the preventers. Does anyone have experience with the Walder Boom Break (preventer) system? I would like to learn if it is any good or just expensive? Our boat is a Dufour GL 380. Thanks!
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Dick
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+x+x+x+x+xI watch from the sidelines, a faint but sympathetic smile playing about my lips, as you guys bat these ideas back and forth concerning ways to prevent your preventers from causing your rigs to self destruct. In the junk rig world, we reckon the long, 180˚ gybe to be safest in heavy weather. Given sufficient searoom, we sail 90˚ by the lee so that sail is taken aback, then it comes across quickly, but harmlessly, and ends up empty of wind with a slack sheet, having nothing like shrouds to stop it short. Because we have to get so far by the lee to cause an intentional gybe, there is much less chance of an unintentional gybe. There is no boom to cause an elfin safety issue, as the "boom" is in fact just another batten. Applying a strong preventer to it would simply cause it to break. The only need I have felt to rig a preventer is in light going with a leftover sea, when the after sail of a ketch or schooner won't lie quietly, and then it's no more than a 6mm nylon line that will stretch if the sail is seriously backwinded, allowing the sail to come across. The fore sail of a ketch or schooner, or a single sail, is so far forward that it is not possible to rig a preventer - no matter, it wouldn't do any good anyway. Of course, we do have our own problems to find answers to: The sheet, as it comes across, must be prevented from snagging anything on the boat, or the crew, and the best way to do that is to rig a semicircular hoop over the cockpit. This comes in handy for rigging shade, as well, so is a good thing to add on a voyaging boat [note to self: must add one to Weaverbird this winter]. When gybing deeply reefed, we have to avoid a "fan-up", as the after ends of the yard and upper battens rise, and may get caught the wrong side of the topping lifts in high-peaked junk rigs. Again, there's an answer, which unsurprisingly is called a fan-up preventer. So yes, we do sometimes rig a preventer, but it's to prevent inconvenience, not to ca Hi David, It is always good to read about alternatives. At some point, if it interests you, I would be interested in your observations of the aero rig (I do not have the name right, I suspect) and how it relates to junk rigs. Casual observation indicates they share some similar design ideas. my best, Dick Dick, the Aero Rig is generally understood to be a commercial version of the Balestron rig, built by Carbospars in Hamble. The Balestron has been used on model yachts for many years, and the Aero Rig has been applied to yachts from a 22ft Hirondelle catamaran up to the 70ft 'Fly' and the 60ft ' Novara' - but I guess that you aren't referring to that rig, but to the soft wing sail that I and others sail under. Am I correct? If so, I'll start a new topic. Hi David, I was just interested in rigs in general and I have seen these aero rigs which, on casual observation, seem to check a lot of boxes. Dick I see. Well, since I've only sailed with one for an afternoon, and since I deplore the "armchair experts" who speak without benefit of first hand knowledge, I'm not really the right person to ask. All I can see is that there is nothing that the Balestron/Aerorig has in common with the rigs under which I sail. Within the OCC, you could contact Steve Brown, for some first hand info. And have a look at this, from Richard Woods, the catamaran designer. But to keep to the topic under discussion here, I can certainly say that they clearly don't need a preventer!
Hi David, Understood and agreed. Thx, Dick
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David Tyler
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+x+x+x+xI watch from the sidelines, a faint but sympathetic smile playing about my lips, as you guys bat these ideas back and forth concerning ways to prevent your preventers from causing your rigs to self destruct. In the junk rig world, we reckon the long, 180˚ gybe to be safest in heavy weather. Given sufficient searoom, we sail 90˚ by the lee so that sail is taken aback, then it comes across quickly, but harmlessly, and ends up empty of wind with a slack sheet, having nothing like shrouds to stop it short. Because we have to get so far by the lee to cause an intentional gybe, there is much less chance of an unintentional gybe. There is no boom to cause an elfin safety issue, as the "boom" is in fact just another batten. Applying a strong preventer to it would simply cause it to break. The only need I have felt to rig a preventer is in light going with a leftover sea, when the after sail of a ketch or schooner won't lie quietly, and then it's no more than a 6mm nylon line that will stretch if the sail is seriously backwinded, allowing the sail to come across. The fore sail of a ketch or schooner, or a single sail, is so far forward that it is not possible to rig a preventer - no matter, it wouldn't do any good anyway. Of course, we do have our own problems to find answers to: The sheet, as it comes across, must be prevented from snagging anything on the boat, or the crew, and the best way to do that is to rig a semicircular hoop over the cockpit. This comes in handy for rigging shade, as well, so is a good thing to add on a voyaging boat [note to self: must add one to Weaverbird this winter]. When gybing deeply reefed, we have to avoid a "fan-up", as the after ends of the yard and upper battens rise, and may get caught the wrong side of the topping lifts in high-peaked junk rigs. Again, there's an answer, which unsurprisingly is called a fan-up preventer. So yes, we do sometimes rig a preventer, but it's to prevent inconvenience, not to ca Hi David, It is always good to read about alternatives. At some point, if it interests you, I would be interested in your observations of the aero rig (I do not have the name right, I suspect) and how it relates to junk rigs. Casual observation indicates they share some similar design ideas. my best, Dick Dick, the Aero Rig is generally understood to be a commercial version of the Balestron rig, built by Carbospars in Hamble. The Balestron has been used on model yachts for many years, and the Aero Rig has been applied to yachts from a 22ft Hirondelle catamaran up to the 70ft 'Fly' and the 60ft ' Novara' - but I guess that you aren't referring to that rig, but to the soft wing sail that I and others sail under. Am I correct? If so, I'll start a new topic. Hi David, I was just interested in rigs in general and I have seen these aero rigs which, on casual observation, seem to check a lot of boxes. Dick I see. Well, since I've only sailed with one for an afternoon, and since I deplore the "armchair experts" who speak without benefit of first hand knowledge, I'm not really the right person to ask. All I can see is that there is nothing that the Balestron/Aerorig has in common with the rigs under which I sail. Within the OCC, you could contact Steve Brown, for some first hand info. And have a look at this, from Richard Woods, the catamaran designer. But to keep to the topic under discussion here, I can certainly say that they clearly don't need a preventer!
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Dick
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Group: Forum Members
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+x+x+xI watch from the sidelines, a faint but sympathetic smile playing about my lips, as you guys bat these ideas back and forth concerning ways to prevent your preventers from causing your rigs to self destruct. In the junk rig world, we reckon the long, 180˚ gybe to be safest in heavy weather. Given sufficient searoom, we sail 90˚ by the lee so that sail is taken aback, then it comes across quickly, but harmlessly, and ends up empty of wind with a slack sheet, having nothing like shrouds to stop it short. Because we have to get so far by the lee to cause an intentional gybe, there is much less chance of an unintentional gybe. There is no boom to cause an elfin safety issue, as the "boom" is in fact just another batten. Applying a strong preventer to it would simply cause it to break. The only need I have felt to rig a preventer is in light going with a leftover sea, when the after sail of a ketch or schooner won't lie quietly, and then it's no more than a 6mm nylon line that will stretch if the sail is seriously backwinded, allowing the sail to come across. The fore sail of a ketch or schooner, or a single sail, is so far forward that it is not possible to rig a preventer - no matter, it wouldn't do any good anyway. Of course, we do have our own problems to find answers to: The sheet, as it comes across, must be prevented from snagging anything on the boat, or the crew, and the best way to do that is to rig a semicircular hoop over the cockpit. This comes in handy for rigging shade, as well, so is a good thing to add on a voyaging boat [note to self: must add one to Weaverbird this winter]. When gybing deeply reefed, we have to avoid a "fan-up", as the after ends of the yard and upper battens rise, and may get caught the wrong side of the topping lifts in high-peaked junk rigs. Again, there's an answer, which unsurprisingly is called a fan-up preventer. So yes, we do sometimes rig a preventer, but it's to prevent inconvenience, not to ca Hi David, It is always good to read about alternatives. At some point, if it interests you, I would be interested in your observations of the aero rig (I do not have the name right, I suspect) and how it relates to junk rigs. Casual observation indicates they share some similar design ideas. my best, Dick Dick, the Aero Rig is generally understood to be a commercial version of the Balestron rig, built by Carbospars in Hamble. The Balestron has been used on model yachts for many years, and the Aero Rig has been applied to yachts from a 22ft Hirondelle catamaran up to the 70ft 'Fly' and the 60ft ' Novara' - but I guess that you aren't referring to that rig, but to the soft wing sail that I and others sail under. Am I correct? If so, I'll start a new topic. Hi David, I was just interested in rigs in general and I have seen these aero rigs which, on casual observation, seem to check a lot of boxes. Dick
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Simon Currin
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Dick I am sorry I don’t know what sort of preventer the McClaren’s use. But his broken boom was at Ardfern for sometime. Simon +x+xI watch from the sidelines, a faint but sympathetic smile playing about my lips, as you guys bat these ideas back and forth concerning ways to prevent your preventers from causing your rigs to self destruct. In the junk rig world, we reckon the long, 180˚ gybe to be safest in heavy weather. Given sufficient searoom, we sail 90˚ by the lee so that sail is taken aback, then it comes across quickly, but harmlessly, and ends up empty of wind with a slack sheet, having nothing like shrouds to stop it short. Because we have to get so far by the lee to cause an intentional gybe, there is much less chance of an unintentional gybe. There is no boom to cause an elfin safety issue, as the "boom" is in fact just another batten. Applying a strong preventer to it would simply cause it to break. The only need I have felt to rig a preventer is in light going with a leftover sea, when the after sail of a ketch or schooner won't lie quietly, and then it's no more than a 6mm nylon line that will stretch if the sail is seriously backwinded, allowing the sail to come across. The fore sail of a ketch or schooner, or a single sail, is so far forward that it is not possible to rig a preventer - no matter, it wouldn't do any good anyway. Of course, we do have our own problems to find answers to: The sheet, as it comes across, must be prevented from snagging anything on the boat, or the crew, and the best way to do that is to rig a semicircular hoop over the cockpit. This comes in handy for rigging shade, as well, so is a good thing to add on a voyaging boat [note to self: must add one to Weaverbird this winter]. When gybing deeply reefed, we have to avoid a "fan-up", as the after ends of the yard and upper battens rise, and may get caught the wrong side of the topping lifts in high-peaked junk rigs. Again, there's an answer, which unsurprisingly is called a fan-up preventer. So yes, we do sometimes rig a preventer, but it's to prevent inconvenience, not to cause it. Hi David, It is always good to read about alternatives. At some point, if it interests you, I would be interested in your observations of the aero rig (I do not have the name right, I suspect) and how it relates to junk rigs. Casual observation indicates they share some similar design ideas. my best, Dick
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Philip Heaton
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+x+x+xWhen I recently overcame barriers to access the Forum, with Bill's assistance, he invited me to start making "controversial posts". So, I'll start here! I am in fundamental disagreement that the best preventer arrangement is a line from boom end to the bow. I know it is a very popular system but I suggest below what I believe is a far superior system. Looking at fundamentals, the primary purpose of a preventer is, when running downwind, to prevent an uncontrolled gybe. I would suggest that an equally important use is to restrain a heavy boom from slopping about in a seaway when winds are light. In fact, aboard Al Shaheen, we used our preventer more often for this than running downwind. A sub-set of the first function is to use a preventer system to actually control a gybe. Any preventer system needs to be effective, and easy and safe to set up in rough weather, preferably without having to go to the bow, and can be controlled from both sides of the boat without having to re-rig after a gybe. The disadvantage of the "boom end to the bow" arrangement is easily seen from the geometry; the angle between the line and the boom is necessarily acute so the line is not very effective in restraining movement of the boom. Consequently, it is not an effective system for restraining movement of a boom in a seaway. I suggest a more effective arrangement is as follows if I can explain it adequately without a diagram. A two-part purchase, on both sides of the boat, positioned just aft of the aft lower shrouds with a line running from a pad-eye on deck through a block with swivel and Wichard hook then back to another block attached to a pad-eye on deck then aft to a rope clutch accessible from the cockpit and positioned so that it can be led to a winch.The block with a Wichard hook is then attached to a boom fitting just aft of the vang. When running downwind with the boom say 70 degrees from the boat's centreline, the attachment point on the boom is nearly vertically above the deck attachment so the boom is restrained very effectively. This system can be set up hard, especially if led to a winch and it may be attached to the boom (both sides) and left in place even when not sailing downwind, or attached in anticipation of a downwind leg. Previous posts have commented on shock loads and the strength toe-rails and deck fittings. In this arrangement, when set up properly and properly used, shock loads do not occur. That's not to say that the system should not be designed for shock loads; it should. In my case I had alloy decks of 6mm plate with 10mm inserts welded in high load areas. I take no credit for this design; it came from the late Mike Pocock, past OCC Commodore formidable designer of ocean cruising boats and was developed from his own experience of a lifetime of ocean cruising.and featured in all his recent ocean cruising boat designs. Hi John, If I understand you correctly, your preventer is attached to the boom just aft of the vang (perhaps a third of the way aft of the gooseneck) and goes to the side deck just aft of the shrouds and then back to the cockpit for adjustment with a b&t arrangement between boom and side deck to a winch for increased purchase. It sounds like there is only one attachment point to the boom. Your use of this arrangement is to control the heavy boom from slopping around in light air and leftover swell. I believe this is a good idea, works well, and we do the same on Alchemy. But that use, to my mind, is more accurately described as a side deck boom vang than as a preventer. Although it can function as both, its main purpose is to keep the boom down and immovable. It can stop unintentional gybes, but with the lever arm so close to the gooseneck, a violent un-controlled gybe might damage the boom. And, yes, a preventer is to prevent uncontrolled gybes, but it is also in place to prevent damage to the boat/boom if the boom tip gets dipped into the sea: perhaps when the roll of the boat coincides with a wave top. This is an admittedly rare, but with enough ocean time, also a predictable event. This is a potent way shock loads might occur. The boom end would immediately be dragged aft and, in the arrangement you describe, the load would go directly to the point-loaded part of the boom just aft of the vang attachment. This, as you mentioned, is set up hard and is almost vertical for very little give. I suspect, the boom would likely just fold up like cardboard (or the attachment to the boom would give way). It is this scenario that a preventer to the boom end is designed to prevent in addition to an uncontrolled gybe. I believe this why preventers are almost always recommended to boom end. Yes, it causes some extra work when gybing the boat, but in ocean passages, this will not often occur and going to the bow when in downwind conditions is not so fearsome. My best, Dick Stevenson, s/v Alchemy Dick You have correctly interpreted my description of the "Pocock" design of preventer system as fitted to many of his ocean cruising boat designs notably Blackjack (the late Mike Pocock), Troubadour (the late Stuart Ingram) , Sadco (the late Noel Marshall), as well as Al Shaheen. In the case of Taonui (Tony Gooch) now renamed Moli (Randall Reeves) Mike Pocock redesigned the rig after Tony's dismasting in the south Atlantic. All these OCC members have put in collectively hundreds of thousands of ocean miles in rugged ocean passages without, to my knowledge experiencing problems arising from "boom in the water". I am a conservative ocean sailor and in circumstances where boom-in-the-water was likely I would reduce sail, itself quite easy downwind with the Pocock reefing system. You commented " It can stop unintentional gybes, but with the lever arm so close to the gooseneck, a violent un-controlled gybe might damage the boom". Not can, it does stop unintentional gybes! With the boom held almost immobile there is very little energy in the gybe so boom damage is very unlikely. In my 60 year sailing career I have experienced many boats with "boom end to bow " preventer systems and can confidently say that I am a complete convert to the system I described which I believe to be infinitely superior. Were I to be commissioning a new boat I would undoubtedly specify it again. It seems that you are describing what Wichard have developed into the Gyb'easy which is attached to the underside of the boom just aft of the vang with lines taken to the side deck aft of the shrouds and then back to clutches at the cockpit (location depends on the boat). The device allows for three levels of friction and is supplied with climbing rope so that it will "slide" through the device. We have one and use it for sloppy seas and when gybing - how good is it for the latter? 6/7 out of 10. It is sold as enabling a controlled i.e. slow gybe from one downwind setting to the other but we do not operate like that, and always winch in the main so that the distance the boom travels is not too great. At the same time we have a standard boom end to bow preventer which we have used for thousands of miles - we trust the preventer and swapping from one side to the other is hassle free as the lines are in two parts and connect with Wichard clips.
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David Tyler
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Group: Forum Members
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+x+xI watch from the sidelines, a faint but sympathetic smile playing about my lips, as you guys bat these ideas back and forth concerning ways to prevent your preventers from causing your rigs to self destruct. In the junk rig world, we reckon the long, 180˚ gybe to be safest in heavy weather. Given sufficient searoom, we sail 90˚ by the lee so that sail is taken aback, then it comes across quickly, but harmlessly, and ends up empty of wind with a slack sheet, having nothing like shrouds to stop it short. Because we have to get so far by the lee to cause an intentional gybe, there is much less chance of an unintentional gybe. There is no boom to cause an elfin safety issue, as the "boom" is in fact just another batten. Applying a strong preventer to it would simply cause it to break. The only need I have felt to rig a preventer is in light going with a leftover sea, when the after sail of a ketch or schooner won't lie quietly, and then it's no more than a 6mm nylon line that will stretch if the sail is seriously backwinded, allowing the sail to come across. The fore sail of a ketch or schooner, or a single sail, is so far forward that it is not possible to rig a preventer - no matter, it wouldn't do any good anyway. Of course, we do have our own problems to find answers to: The sheet, as it comes across, must be prevented from snagging anything on the boat, or the crew, and the best way to do that is to rig a semicircular hoop over the cockpit. This comes in handy for rigging shade, as well, so is a good thing to add on a voyaging boat [note to self: must add one to Weaverbird this winter]. When gybing deeply reefed, we have to avoid a "fan-up", as the after ends of the yard and upper battens rise, and may get caught the wrong side of the topping lifts in high-peaked junk rigs. Again, there's an answer, which unsurprisingly is called a fan-up preventer. So yes, we do sometimes rig a preventer, but it's to prevent inconvenience, not to ca Hi David, It is always good to read about alternatives. At some point, if it interests you, I would be interested in your observations of the aero rig (I do not have the name right, I suspect) and how it relates to junk rigs. Casual observation indicates they share some similar design ideas. my best, Dick Dick, the Aero Rig is generally understood to be a commercial version of the Balestron rig, built by Carbospars in Hamble. The Balestron has been used on model yachts for many years, and the Aero Rig has been applied to yachts from a 22ft Hirondelle catamaran up to the 70ft 'Fly' and the 60ft ' Novara' - but I guess that you aren't referring to that rig, but to the soft wing sail that I and others sail under. Am I correct? If so, I'll start a new topic.
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Dick
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+xDick Absolutely yes it would. It is infinitely adjustable SI can be a boom brake or a boom lock. We use ours as a brake and only lock it to secure the boom when the sail is not up. Bill McLaren managed to break his boom by forgetting to release a conventional preventer before gybing (planned). That wouldn’t have happened with a Dutchman. Simon +x+xWe have been using a Dutchman for the last 13 years which does all of these things, is permanently rigged, very simple to use and adjustable.It would, however, be nice to have some downwind sailing to use it more! Hi Simon, Would the Dutchman release enough and quickly enough to prevent boom damage were you to dip the boom end into the sea at speed? Thanks, Dick Hi Simon, Interesting. Thanks for the input: it sounds like a worthwhile piece of kit. When you report that Bill's boom busted because he forgot to release his conventional boom prior to a planned gybe: what was the design of the conventional preventer? Where was it attached to the boom? Thanks, Dick
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Dick
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+xI watch from the sidelines, a faint but sympathetic smile playing about my lips, as you guys bat these ideas back and forth concerning ways to prevent your preventers from causing your rigs to self destruct. In the junk rig world, we reckon the long, 180˚ gybe to be safest in heavy weather. Given sufficient searoom, we sail 90˚ by the lee so that sail is taken aback, then it comes across quickly, but harmlessly, and ends up empty of wind with a slack sheet, having nothing like shrouds to stop it short. Because we have to get so far by the lee to cause an intentional gybe, there is much less chance of an unintentional gybe. There is no boom to cause an elfin safety issue, as the "boom" is in fact just another batten. Applying a strong preventer to it would simply cause it to break. The only need I have felt to rig a preventer is in light going with a leftover sea, when the after sail of a ketch or schooner won't lie quietly, and then it's no more than a 6mm nylon line that will stretch if the sail is seriously backwinded, allowing the sail to come across. The fore sail of a ketch or schooner, or a single sail, is so far forward that it is not possible to rig a preventer - no matter, it wouldn't do any good anyway. Of course, we do have our own problems to find answers to: The sheet, as it comes across, must be prevented from snagging anything on the boat, or the crew, and the best way to do that is to rig a semicircular hoop over the cockpit. This comes in handy for rigging shade, as well, so is a good thing to add on a voyaging boat [note to self: must add one to Weaverbird this winter]. When gybing deeply reefed, we have to avoid a "fan-up", as the after ends of the yard and upper battens rise, and may get caught the wrong side of the topping lifts in high-peaked junk rigs. Again, there's an answer, which unsurprisingly is called a fan-up preventer. So yes, we do sometimes rig a preventer, but it's to prevent inconvenience, not to cause it. Hi David, It is always good to read about alternatives. At some point, if it interests you, I would be interested in your observations of the aero rig (I do not have the name right, I suspect) and how it relates to junk rigs. Casual observation indicates they share some similar design ideas. my best, Dick
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David Tyler
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I watch from the sidelines, a faint but sympathetic smile playing about my lips, as you guys bat these ideas back and forth concerning ways to prevent your preventers from causing your rigs to self destruct.
In the junk rig world, we reckon the long, 180˚ gybe to be safest in heavy weather. Given sufficient searoom, we sail 90˚ by the lee so that sail is taken aback, then it comes across quickly, but harmlessly, and ends up empty of wind with a slack sheet, having nothing like shrouds to stop it short. Because we have to get so far by the lee to cause an intentional gybe, there is much less chance of an unintentional gybe. There is no boom to cause an elfin safety issue, as the "boom" is in fact just another batten. Applying a strong preventer to it would simply cause it to break. The only need I have felt to rig a preventer is in light going with a leftover sea, when the after sail of a ketch or schooner won't lie quietly, and then it's no more than a 6mm nylon line that will stretch if the sail is seriously backwinded, allowing the sail to come across. The fore sail of a ketch or schooner, or a single sail, is so far forward that it is not possible to rig a preventer - no matter, it wouldn't do any good anyway.
Of course, we do have our own problems to find answers to:
The sheet, as it comes across, must be prevented from snagging anything on the boat, or the crew, and the best way to do that is to rig a semicircular hoop over the cockpit. This comes in handy for rigging shade, as well, so is a good thing to add on a voyaging boat [note to self: must add one to Weaverbird this winter].
When gybing deeply reefed, we have to avoid a "fan-up", as the after ends of the yard and upper battens rise, and may get caught the wrong side of the topping lifts in high-peaked junk rigs. Again, there's an answer, which unsurprisingly is called a fan-up preventer. So yes, we do sometimes rig a preventer, but it's to prevent inconvenience, not to cause it.
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