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In article , DSK
wrote: But it does add weight down low, and it's relatively cheap... if it gives the boat enough life span to last out your likely tenure of ownership, why not? Peter Wiley wrote: Yeah, if you want to look at it like that, fair enough. It makes me uncomfortable tho. It would me, too. But as a practical matter of boat-keeping, you cannot make everything perfect. Doug, there's nothing wrong with the junk rig on that hull and I don't understand why you think there is. It was designed for the rig. I just don't like junks. They have a lot of windage, True. proportionately more weight aloft, But why is this bad? Taken to a logical conclusion, you're saying the less weight aloft the better. From a standpoint of stability & speed, that's true. But I agree with you that there are other factors. Yeah. Like, taken to its ultimate, you have no rig at all and end up with..... a tug boat! ... In practice this has been shown to be a bad assumption. Weight aloft damps out roll, extends roll period and provides more inertia to resist rolling over. I agree that too much weight aloft isn't going to be good either, but the implication that more is bad doesn't hold up. Depends on what you want the boat to do. Roll damping is good, but weight aloft also hurts LPOS. Don't I recall some data from the Fastnet fiasco of some years ago WRT lack of weight aloft as a contrib factor to rolling over? I don't really have any feelings pro/con about the looks. They're different is all. As to pointing, true but so what? It's not designed as any sort of racing vessel. That hull form won't point as high as a fin keeled sloop no matter what rig it has. It's not designed for it. Dunno about pointing, it's true that it's not going to climb to windward like a 12-Meter no matter what rig you put on that hull. But I'm uncomfortable with a boat, no matter how "cruisy," that does not go to windward pretty well, So - what do you mean by 'pretty well'? You're an engineer - give some figures. or (as many cruising boats) will only make ground to weather at all in ideal conditions. Too easy to get trapped, and too dependent on the engine (odd as it may sound for a tug boat owner to say that). Yeah. But what makes you think this criticism applies ot all or even most junk rigs? I think you've taken assumptions and treated them as facts. There are at least 2 examples - the Colvin Gazelle design and the Benford dory - that can & do go to windward in somewhat less than ideal conditions. The first Gazelle was built and sailed for some years sans engine. The Hill's dory ditto. What's worse, many boats that have difficulty getting to windward are ulso unhandy on the helm & reluctant in stays. It's a vicious circle. OK, true. But do you think either of these things are peculiar to or universal amongst junk rigs? If so, why? At least 2 people with junk rigs disagree with you. Where is the basis for your implication that junk rig vessels are a) difficult or impossible to sail to windward b) unhandy on the helm and c) reluctant in stays. It might be a vicious circle, but you haven't demonstrated that it is a universal characteristic of junk rigs, and people with in excess of 100,000 miles sailing them disagree with you. I'm open to argument, but all you're doing is making assertions, and those without reference to any recognised authority. But it's dependent on the cutting edge of 17th century technology. With just a teensy bit more budget, Like somewhere in the vicinity of 10X, I'd venture to say...... Not at all. Part of what I'm trying to say is that all the stuff to build a rig like that can be picked up 2nd hand or free, if you don't mind spending the time hunting around. Around any recreational sailing area, it's easier to find parts for than a junk rig. Doug, almost *any* rig can be picked up 2nd hand or free, if you don't mind spending time hunting around. I really can't see this is relevant. I think the people who extol the junk rig are very full of descriptives like "no rig easier to control" when that's not really quantifiable... and the rig they are extolling is also "easier to control" because there's less of it. So? Still a valid point, if you agree that the objective of a rig is to get you from A to B in a reasonable time. 'Reasonable' is subject to definition but I really don't think 140 mile days for a cruising boat is bad. I also wonder how many of them have much experience with modern rigs... the same crowd seems very down on roller furling & self tailing winches. Another point is that "easy to control" and "inexpensive" are the junk rigs *only* two virtues. How about long lived, difficult to damage and easy to repair? On what point(s) of sailing? Upwind, maybe - if you care. IIRC Colvin said the rig points as high as a Marconi rig but made more leeway. That may have been true, given less effective underwater foils, back in the 1960s. I think we're back to the draft factor again. You're cherry picking. If you put a highly efficient to windward rig on a shoal draft cruising vessel, it ain't going to work too well. Keep the engineering params in mind - it's a cruising vessel with shoal draft for gunkholing. Demonstrate, within these constraints, your assertion that the Marconi rig will outpoint the junk rig. I'm happy to be convinced as I don't know from personal experience myself. ... OTOH it tended to run away downwind as the sails could be set wing & wing easily, without the main blanketing the fore. Sorry, I don't think that a heavy junk-rigged schooner What do you define as 'heavy'? What displacement? is going to "run away" from any but the pokiest marconi rigged boat, and that without any flying sails set. ... You could also sail by the lee without any dramas A matter of skill on the part of the helmsman ... and a gybe was also pretty drama free as the balanced lug damped out the motion when the sails swung across. Now that much is true. Add that to the list of virtues... "easy to control", cheap, and easy to gybe. ... Short tacking up a channel was effortless. So is a gaff cat, or cat ketch, or sloop with no jib or self-tacking jib... and a sloop with a small jib is not difficult. True. Now, how do those rigs compare to the junk rig in terms of sail area set? I simply do not believe that you can build a fully battened Marconi rig for anything like the price of a junk rig. Why not? Go scrounge around a boat yard nowadays, you'll find lots of 2nd hand parts & components for such a rig... and darn few junk rig parts. Ummmmm, that might be because there are damn few - I hesitate to say none - specific junk rig parts. Feel free to correct me by listing some. Therefore, it's a wash at best. I just did a Google search for used sail batten cars. Guess how many sites selling them popped up? Nice round number........ Of course, if you're shopping at the farm & truck supply place, then maybe you can cobble together something, and it won't cost much... but then neither will the boatyard cast-offs. ... Nothing I've ever read indicates that you can even get close. Are you going to have the same height mast(s)? If so, where's the gain in sail area? In staysails & flying sails, Wellllllll, the Gazelle has a jib and a fisherman as well as its 2 junk sails. So no gain at all, then. and the Marconi sails are more efficient. Doug, Marconi sails are more efficient *to windward*, and only then if in very good condition. As soon as they get saggy & baggy, the efficiency goes to hell. On reaching & running the tall Marconi rig is inefficient compared to almost anything else. I can't find any authority that says different. Quote me one. Quoting from: http://www.kastenmarine.com/gaff_rig.htm It is well known that higher aspect sails produce greater lift when close hauled.* It not so widely known however that high aspect sails stall much more readily as the angle of attack widens. As A/R gets higher, sails get less and less efficient at pulling when anywhere but close hauled. For racing, where windward performance is of prime importance, it has been shown that an aspect ratio greater than 6 is of little use on monohull racing craft.* An appropriate range will be an A/R of from 4 to 6. A polar diagram showing lift vs. drag plotted for sails having the same area but differing aspect ratios very graphically shows that the favored lift / drag position is quickly handed off to shorter and shorter rigs as a sail is eased. If you would like see this data graphically presented, please have a look at the Aero-hydrodynamics of Sailing by Marchaj, p. 444, Fig. 2.138. A study of this data shows that the most favorable aspect ratios for ocean cruising, where all-around performance is the goal, an aspect ratio from 2.5 to 3.5 is very appropriate, with an approximate upper limit of around A/R 4.* Naturally, these are not "hard" boundaries, only guidelines.* In most cases, a compromise is struck in consideration of the times inevitably spent sailing to windward. In the data presented by Marchaj, angle of incidence of the sail is plotted against lift vs drag.* A sail having an A/R of 6 performs exceedingly well at an angle of attack to the apparent wind of 10 degrees, where lift divided by drag (L/D) yields a ratio of around 8.5.* At 10 degrees, a sail with A/R 3 has an L/D ratio of 6.5.* At 15 degrees, the A/R 6 sail has an L/D ratio of 4.47, and the A/R 3 sail has an L/D ratio of 4.5.* At 20 degrees, the A/R 6 sail has an L/D ratio of 2.7, while the A/R 3 sail has an L/D ratio of 3.3, and so forth.* By the time an angle of attack of 30 degrees is reached, the favored position is handed off to a sail with an A/R of 1...! The salient point is that extremely high aspect sails are not "bad" sails, they are just not a requirement for general ocean cruising, where it is rare to be sailing dead to windward.* When required to do so, sails with an A/R of from 3 to 4 will perform quite well when just eased off a few degrees. ====================================== Do you disagree with this? Look, we're referring to cruising boats here, as that's what the Gazelle is. That means few people doing boat handling for up to 30 days at sea. Every extra sail you take means that much less space for other gear & supplies. Seems to me that you're fixated on windward sailing ability to the detriment of other factors. But with less weight and less windage aloft, there's no reason to not go higher. In fact a higher rig of the same weight provides more damping.... so there you go! ... If not, how much higher are you going to go and how do you propose to brace the mast(s)? Adding spreaders and more rigging wire costs money, increases the rig loadings and requires either higher tensile strength materials or thicker materials to gain the needed strength. True enough, and those materials are very common & easy to find. ............. at a price. I'm in the marine engineering business, I know what stuff costs. As I said, if one is determined to use 17th century technology, then the junk rig makes a great choice. And if you're determined to use 21C technology, that's a great choice. For your chandler. If you have deep pockets. For cruising vessels, there's a point somewhere in between that's appropriate. If you're cruising from marina to marina and have spare everything a phone call away, one level of equipment might be appropriate. If you're operating in distant waters, another might be better. Would you put rod rigging on a cruising boat under all circumstances? If not, why not? It's more efficient in terms of reduced stretch. ....The batten cars cost a hell of a lot more than the junk sail lacing. The sailcloth for a battened Marconi sail needs to be of a lot higher standard than for a junk sail. Etc. In other words, you want to stitch burlap bags together and hang it on a rig assembled from odds & ends out of a discount plumber's supply? Be my guest... I won't even fuss when you brag about how easy it is to control! Come off it. Do you need mylar sails for cruising on a Marconi rigged boat? They've got better material specs than Dacron. If you're not using mylar, does that mean you're using the equiv of burlap? How about rod rigging instead of 1x19 s/steel? Or galv wire instead of s/steel wire? That bit of argument is reminiscent of Bobsprit. When you can't refute the point, go for the exaggeration and hope nobody notices. ... I point out that if you increase the rig height then you're most likely going to have to start reefing in lighter air due to the extra leverage aloft, unless you also increase ballast/draft as well. There goes the shoal draft gunkholing ability..... If the boat *sails* well in relatively light air, thent what's the issue of having to reef? As long as the boat sails well when reefed, and the reef can be taken in or shaken out without too much labor ...and with the solid vang & lazy jacks, it's a matter of easing one line and pulling another, while the sailing characterisitics remain pretty much the same... Yeah, ok, point - there's no real difference. This particular vessel (Migrant) has been recorded as doing consistent 140+ mile days cruising over many passages & many years. That's pretty good. OTOH it's also a big boat. 140 mile days on a 40' + LWL is comparable to 90 mile days with a 32' LWL. Except it's 35' LWL, 42' LOD IIRC. I'd need to check the exact figures but that's close. How many production boats have got to that number of hulls in the water? Only the ones that have been very successfully marketed... as have the junk rigs! Ah. Damn few to none, then, that you can find. Weekend is here and I'm going sailing as I only have 4 weeks left in this year. This can wait till next week or forever, depending........ PDW |
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