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Capt. JG wrote:
I for one have no interest in owning a 26 foot boat that comes with a 70hp engine. This is the antithesis of what sailing is all about. I wouldn't mind having a 70hp engine in our 36 foot boat ![]() JimC wrote: The boat is built to be balanced in the water with crew and with an outboard of 50 - 70 hp. If the moter were removed, the boat would tend to "lean" forwardly, with the stern too high in the water. The weight of the outboard is far less than the weight of a typical diesel in a 27-29 In other words, the boat is ballasted with a lot of mass far forward, as Jeff was contending earlier. Jeff wrote: Not really. A 50 Hp 4-stroke weighs over 200 pounds - Honda claims the lightest at about 210, Suzuki's is about 250. A Yanmar 2YM15 is 249 with transmission, though the shaft and prop is extra. There really isn't a lot of difference in weight. Big difference in efficiency, though. ft boat, although, of course, the weight of the diesel is better positioned. There is a huge difference here. In fact, much of the weight of a diesel could be considered ballast. At the very least, it contributes little to the pitch moment. Between the ballast far forward and the engine wieght far aft, it's hard to imagine a worse set-up for good sailing performance. The chief disadvantage of the larger engine is that it gives Mac-bashers who have never sailed a 26M another opportunity to turn their noses up at Mac owners. Although the Macs don't point as well as conventional boats with weighted keels, Does the weight of the keel affect pointing? Funny, I always thought that had to do with the basic rig design... aspect ratio, sheeting base, etc etc... keel foil configuration plays into it somewhat I'm sure, but how does the wind know (and why would it care) about the weight of the keel? Are you tacitly admitting that Mac-26Ms don't sail to windward very well? We already know that's true of the M26X. ... I doubt seriously that the weight of the motor is a major factor. OTOH those of us who have been rigorously schooled to sail *well* have been taught to keep weight out of the ends of the boat. Any one design racer will have seen (if he's paid the slightest attention) a boat with crew sitting spread fore & aft getting passed by a boat with two guys sitting close together. ... Rather, it's the compromises relating to the internal ballast, trailerable hull, and lack of weighted keel. (The metactric effect.) Please explain. I know about metacentric height, but have never heard of "the metacentric effect." Jeff wrote: Actually, the engine by itself doesn't bother me that much. I think that if you asked detractors if they would accept an engine with 3 time the power if there was no cost in weight, fuel usage, initial or maintenance costs, etc., most would take it. Sure. Why not? I'm not sure there's any way to seperate the added horsepower from the added speed & fuel usage though. ... The problem is that most hulls are designed for sailing, not powering at high speed. The Mac made a number of compromises - a flat "powerboat" hull, no external ballast, that greatly diminish its sailing ability. Ever seen the hull of an 18-footer skiff? They are very wide & flat aft. Of course, they are *also* designed to generate significant amounts of horsepower from their rig, and can plane readily. The Mac26-M is not and can not. My boat actually could accept large engines - the builder put twin 100's into the smaller version of it, and with only minor hull mods, created a best selling powercat. But this formula does not work well for monohulls. I'm not so sure it can't... I am sure that it can't be done both well and for cheap. A smallish motorsailer that had very good sailing performance might be quite a nice boat, but it would look more like a Melges 24 than a Mac26-M. The more important factor, however, is that they are lots of fun to sail. So you say. Why is it that you almost never post a trip report? Maybe he's too busy having fun? Frankly, I have had a good time sailing two shipping pallets skinned with roofing paper & a bedsheet sail. It was like a really cheap little scow. So I can believe that Jim enjoys sailing his Mac26-M. However I am not spending the rest of my life boasting about what super-dooper hot performing sailing machine that 1-hour scavenged scow was. JimC seems to be trying to convince others (maybe himself?) of several claims that contradict the obvious truth. DSK |
#2
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Neither would I. I just don't want one on a 26'er.
-- "j" ganz @@ www.sailnow.com "DSK" wrote in message .. . Capt. JG wrote: I for one have no interest in owning a 26 foot boat that comes with a 70hp engine. This is the antithesis of what sailing is all about. I wouldn't mind having a 70hp engine in our 36 foot boat ![]() JimC wrote: The boat is built to be balanced in the water with crew and with an outboard of 50 - 70 hp. If the moter were removed, the boat would tend to "lean" forwardly, with the stern too high in the water. The weight of the outboard is far less than the weight of a typical diesel in a 27-29 In other words, the boat is ballasted with a lot of mass far forward, as Jeff was contending earlier. Jeff wrote: Not really. A 50 Hp 4-stroke weighs over 200 pounds - Honda claims the lightest at about 210, Suzuki's is about 250. A Yanmar 2YM15 is 249 with transmission, though the shaft and prop is extra. There really isn't a lot of difference in weight. Big difference in efficiency, though. ft boat, although, of course, the weight of the diesel is better positioned. There is a huge difference here. In fact, much of the weight of a diesel could be considered ballast. At the very least, it contributes little to the pitch moment. Between the ballast far forward and the engine wieght far aft, it's hard to imagine a worse set-up for good sailing performance. The chief disadvantage of the larger engine is that it gives Mac-bashers who have never sailed a 26M another opportunity to turn their noses up at Mac owners. Although the Macs don't point as well as conventional boats with weighted keels, Does the weight of the keel affect pointing? Funny, I always thought that had to do with the basic rig design... aspect ratio, sheeting base, etc etc... keel foil configuration plays into it somewhat I'm sure, but how does the wind know (and why would it care) about the weight of the keel? Are you tacitly admitting that Mac-26Ms don't sail to windward very well? We already know that's true of the M26X. ... I doubt seriously that the weight of the motor is a major factor. OTOH those of us who have been rigorously schooled to sail *well* have been taught to keep weight out of the ends of the boat. Any one design racer will have seen (if he's paid the slightest attention) a boat with crew sitting spread fore & aft getting passed by a boat with two guys sitting close together. ... Rather, it's the compromises relating to the internal ballast, trailerable hull, and lack of weighted keel. (The metactric effect.) Please explain. I know about metacentric height, but have never heard of "the metacentric effect." Jeff wrote: Actually, the engine by itself doesn't bother me that much. I think that if you asked detractors if they would accept an engine with 3 time the power if there was no cost in weight, fuel usage, initial or maintenance costs, etc., most would take it. Sure. Why not? I'm not sure there's any way to seperate the added horsepower from the added speed & fuel usage though. ... The problem is that most hulls are designed for sailing, not powering at high speed. The Mac made a number of compromises - a flat "powerboat" hull, no external ballast, that greatly diminish its sailing ability. Ever seen the hull of an 18-footer skiff? They are very wide & flat aft. Of course, they are *also* designed to generate significant amounts of horsepower from their rig, and can plane readily. The Mac26-M is not and can not. My boat actually could accept large engines - the builder put twin 100's into the smaller version of it, and with only minor hull mods, created a best selling powercat. But this formula does not work well for monohulls. I'm not so sure it can't... I am sure that it can't be done both well and for cheap. A smallish motorsailer that had very good sailing performance might be quite a nice boat, but it would look more like a Melges 24 than a Mac26-M. The more important factor, however, is that they are lots of fun to sail. So you say. Why is it that you almost never post a trip report? Maybe he's too busy having fun? Frankly, I have had a good time sailing two shipping pallets skinned with roofing paper & a bedsheet sail. It was like a really cheap little scow. So I can believe that Jim enjoys sailing his Mac26-M. However I am not spending the rest of my life boasting about what super-dooper hot performing sailing machine that 1-hour scavenged scow was. JimC seems to be trying to convince others (maybe himself?) of several claims that contradict the obvious truth. DSK |
#3
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![]() DSK wrote: Capt. JG wrote: I for one have no interest in owning a 26 foot boat that comes with a 70hp engine. This is the antithesis of what sailing is all about. I wouldn't mind having a 70hp engine in our 36 foot boat ![]() JimC wrote: The boat is built to be balanced in the water with crew and with an outboard of 50 - 70 hp. If the moter were removed, the boat would tend to "lean" forwardly, with the stern too high in the water. The weight of the outboard is far less than the weight of a typical diesel in a 27-29 In other words, the boat is ballasted with a lot of mass far forward, as Jeff was contending earlier. I never stated that the ballast mass is "far forward", DSK, and I don't think Jeff did either. As to the moment of inertia during pitching, the motor, after all, is about the same weight as a crew member, and though its slightly aft of the cockpit, its weight (mass) is not a great factor, as some of your buddies claim. (As previously stated: "I doubt seriously that the weight of the motor is a major factor.") Jeff wrote: Not really. A 50 Hp 4-stroke weighs over 200 pounds - Honda claims the lightest at about 210, Suzuki's is about 250. A Yanmar 2YM15 is 249 with transmission, though the shaft and prop is extra. There really isn't a lot of difference in weight. Big difference in efficiency, though. ft boat, although, of course, the weight of the diesel is better positioned. There is a huge difference here. In fact, much of the weight of a diesel could be considered ballast. At the very least, it contributes little to the pitch moment. Between the ballast far forward and the engine wieght far aft, it's hard to imagine a worse set-up for good sailing performance. Actually, of course, the ballast is centered only slightly forward of amidships, as we have already discussed. The motor, weighing only 200 - 250 lb., is of little consequence. The chief disadvantage of the larger engine is that it gives Mac-bashers who have never sailed a 26M another opportunity to turn their noses up at Mac owners. Although the Macs don't point as well as conventional boats with weighted keels, Does the weight of the keel affect pointing? Funny, I always thought that had to do with the basic rig design... aspect ratio, sheeting base, etc etc... keel foil configuration plays into it somewhat I'm sure, but how does the wind know (and why would it care) about the weight of the keel? As you probably know, a weighted keel positioned five or six feet below the hull entails more leverage and provides a more efficient righting moment than the same weight of ballast,particularly water ballast, positioned within the hull. For its size, it a deep, weighted keel is more efficient in keeping the boat in a nearly upright position as winds increase, permitting more efficient translation of the force of the wind into forwardly directioned forces. The aspect ration of the keel is, of course, also a factor in preventing lateral "sliding" of the boat, and the Mac 26M has a retractable dagger board that is quite narrow. To compensate for the relative inefficiency of the water ballast as compared with a heavy,weighted keel, the Mac has a total ballast sufficiently large to keep the boat upright. After years of mods and improvements, the current model, with appropriate reefing, sails ratehr well in pretty heavy weather. (For example, mine was heeling at only 20 degrees Saturday in 15 knot winds, with the first reef taken in.) Are you tacitly admitting that Mac-26Ms don't sail to windward very well? We already know that's true of the M26X. No I'm not tacitly admitting anything. I'm openly stating (once again) that they don't sail to windward as well as conventional sailboats with weighted keels. It's one of the compromises of the particular design. ... I doubt seriously that the weight of the motor is a major factor. OTOH those of us who have been rigorously schooled to sail *well* have been taught to keep weight out of the ends of the boat. Any one design racer will have seen (if he's paid the slightest attention) a boat with crew sitting spread fore & aft getting passed by a boat with two guys sitting close together. I'll remember that the next time I'm racing, DSK. But actually, I didn't buy the Mac with that in mind. I bought it to enjoy the overall sailing experience. ... Rather, it's the compromises relating to the internal ballast, trailerable hull, and lack of weighted keel. (The metactric effect.) Please explain. I know about metacentric height, but have never heard of "the metacentric effect." The metacentric height is considered the distance between the center of gravity and the metacenter. By "metacentric effect", I was referring to the fact that the righting force is proportional to the metacentric height times the sine of the angle of heel. Thus, a conventional boat, with weighted keel low in the water, would have a lower center of gravity than the Mac and would therefor tend to be less tender. Again, the Mac 26M does entail compromises, but after a number of years of development and modifications, it does the job. (If it didn't, I would have capsized Saturday in the 15-knot winds instead of sailing along with a 20 degree heel.- Right? Jeff wrote: Actually, the engine by itself doesn't bother me that much. I think that if you asked detractors if they would accept an engine with 3 time the power if there was no cost in weight, fuel usage, initial or maintenance costs, etc., most would take it. Sure. Why not? I'm not sure there's any way to seperate the added horsepower from the added speed & fuel usage though. ... The problem is that most hulls are designed for sailing, not powering at high speed. The Mac made a number of compromises - a flat "powerboat" hull, no external ballast, that greatly diminish its sailing ability. Ever seen the hull of an 18-footer skiff? They are very wide & flat aft. Of course, they are *also* designed to generate significant amounts of horsepower from their rig, and can plane readily. The Mac26-M is not and can not. No, the 2M isn't flat aft. Instead, as can be readily seen from looking at the stern, it has a pronounced V-shape, which extends from the stern to amidships. In contrast with your statement, it does plane easily and smoothly. And it's also a lot of fun to sail. My boat actually could accept large engines - the builder put twin 100's into the smaller version of it, and with only minor hull mods, created a best selling powercat. But this formula does not work well for monohulls. I'm not so sure it can't... I am sure that it can't be done both well and for cheap. A smallish motorsailer that had very good sailing performance might be quite a nice boat, but it would look more like a Melges 24 than a Mac26-M. The more important factor, however, is that they are lots of fun to sail. So you say. Why is it that you almost never post a trip report? Maybe he's too busy having fun? Frankly, I have had a good time sailing two shipping pallets skinned with roofing paper & a bedsheet sail. It was like a really cheap little scow. So I can believe that Jim enjoys sailing his Mac26-M. However I am not spending the rest of my life boasting about what super-dooper hot performing sailing machine that 1-hour scavenged scow was. And just where did I say that the Mac 26M is a "sooper-dooper hot performing sailing machine", or anything of the kind? I've said that the Mac 26M is fun to sail, but I have consistently stated that it doesn't sail or point as well as a large displacement boat. Instead of saying the Mac is a great sailing machine, I've said that it has limitations and disadvantages when compared with conventional vessels. Do you consider lying about what I said, as you just did, a necessary evil acceptable when convenient, DSK? Do you consider it appropriate to ignore any principles of ethics because, after all, you are merely involved in some more Mac-Bashing, apparently for the amusement and "atta-boys" of your buddies? Do you have no self-respect whatsoever, DSK? Jim |
#4
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In other words, the boat is ballasted with a lot of mass far forward,
as Jeff was contending earlier. JimC wrote: I never stated that the ballast mass is "far forward", DSK, and I don't think Jeff did either. If Jeff didn't, then why were you arguing with him over that exact point? ... As to the moment of inertia during pitching, the motor, after all, is about the same weight as a crew member A very very large & well-fed crew member. ... and though its slightly aft of the cockpit In other words, it is as far aft as it can be, and still be part of the boat. .... its weight (mass) is not a great factor, as some of your buddies claim. (As previously stated: "I doubt seriously that the weight of the motor is a major factor.") Whoever stated that is an idiot. It's 200+ pounds at the farthest aft extremity of the boat. You want to claim this doesn't affect pitching moment "very much" whereas knowledgable sailors know that weight in the far ends of the boat is bad for steering & worse for pitching. Not a "major factor?" Between the ballast far forward and the engine wieght far aft, it's hard to imagine a worse set-up for good sailing performance. Actually, of course, the ballast is centered only slightly forward of amidships, as we have already discussed. The motor, weighing only 200 - 250 lb., is of little consequence. Yeah, I bet you can carry it with one hand. "Of little consequence" except for the boat's poor steering & worse pitching. Does the weight of the keel affect pointing? Funny, I always thought that had to do with the basic rig design... aspect ratio, sheeting base, etc etc... keel foil configuration plays into it somewhat I'm sure, but how does the wind know (and why would it care) about the weight of the keel? As you probably know, a weighted keel positioned five or six feet below the hull entails more leverage Which does *what* exactly, for POINTING? Please explain. .... provides a more efficient righting moment than the same weight of ballast,particularly water ballast, positioned within the hull. Why "particularly" water ballast? Does gravity care if a ton of ballast is water or lead or feathers? .... For its size, it a deep, weighted keel is more efficient in keeping the boat in a nearly upright position as winds increase, permitting more efficient translation of the force of the wind into forwardly directioned forces. That may help it's speed, but how will it affect the boat's pointing? ... The aspect ration of the keel is, of course, also a factor in preventing lateral "sliding" of the boat, No it isn't. The aspect ratio is a factor in the expected lift/drag ratio of the foil. The total amount of lift generated by the foil determines the leeway or lateral sliding of the boat. .... and the Mac 26M has a retractable dagger board that is quite narrow. Meaning what? You started out to explain pointing, and so far you've fumbled around in the dark in left field. You *almost* mentioned something that might be related to pointing, but you got it worng anyway. ... To compensate for the relative inefficiency of the water ballast as compared with a heavy,weighted keel, the Mac has a total ballast sufficiently large to keep the boat upright. After years of mods and improvements, the current model, with appropriate reefing, sails ratehr well in pretty heavy weather. (For example, mine was heeling at only 20 degrees Saturday in 15 knot winds, with the first reef taken in.) And what was your VMG to windward? Best speed on a reach? If the wind is strong enough to reef, then you should be able to plane. You say the boat sails rather well, my observation (many times over) is that they sail poorly. Almost any decent sailboat will beat them downwind and a potting shed will beat them upwind. Are you tacitly admitting that Mac-26Ms don't sail to windward very well? We already know that's true of the M26X. No I'm not tacitly admitting anything. I'm openly stating (once again) that they don't sail to windward as well as conventional sailboats with weighted keels. It's one of the compromises of the particular design. So... we can agree it sucks at sailing to windward. Do you think perhaps the weight of the motor... and the huge flat aft sections necessary to float it... have anything to do with that? I'll remember that the next time I'm racing, DSK. But actually, I didn't buy the Mac with that in mind. I bought it to enjoy the overall sailing experience. Actually, if you're reefing & heeling & all that stuff, it must be almost the same as sailing.You mean, the experience of sitting on a boat with sails up? Pity you need that huge motor to actually go anywhere. BTW many sailboats will go faster than 13 knots. ... Rather, it's the compromises relating to the internal ballast, trailerable hull, and lack of weighted keel. (The metactric effect.) Please explain. I know about metacentric height, but have never heard of "the metacentric effect." The metacentric height is considered the distance between the center of gravity and the metacenter. By "metacentric effect", I was referring to the fact that the righting force is proportional to the metacentric height times the sine of the angle of heel. Thus, a conventional boat, with weighted keel low in the water, would have a lower center of gravity than the Mac and would therefor tend to be less tender. Good, but not quite right. The metacenter is figured as height above the waterline. A lower center of gravity doesn't affect the metacenter at all, it is strictly a function of hull shape. Shall I explain curves of righting moment? It's a key to understanding how different boats sail differently... nah, maybe some other time. For now, let's just say that there are effectively 2 forces producing righting moment, one is the hull shape which produces initial stability... how tender the boat feels when you step onto the gun'l from the dock, for example... and the other is reserve stability, which is affected by how low & heavy the ballast is, and produces righting moment at high angles of heel. ... Again, the Mac 26M does entail compromises, but after a number of years of development and modifications, it does the job. (If it didn't, I would have capsized Saturday in the 15-knot winds instead of sailing along with a 20 degree heel.- Right? The fact that the boat doesn't fall over helplessly in 15 knot winds is good, agreed. No, the 2M isn't flat aft. I guess it depends on what you call "flat." http://www.improb.com/airchives/pape...i3/kansas.html ... In contrast with your statement, it does plane easily and smoothly. Then why won't it plane under sail? Lots and lots and lots of boats plane under sail. It has been known how to design sailboat hulls & rigs to plane since 1928. How the heck modern can the Mac 26 M be if it doesn't incorporate this concept? And just where did I say that the Mac 26M is a "sooper-dooper hot performing sailing machine", or anything of the kind? Well, lately, you've been admitting that it's slow. But hey, that's of no consequence, just like the increased hobby-horsing due to the weight of the engine on the transom. ... I've said that the Mac 26M is fun to sail, but I have consistently stated that it doesn't sail or point as well as a large displacement boat. Or a small one. ... Instead of saying the Mac is a great sailing machine, I've said that it has limitations and disadvantages when compared with conventional vessels. It's all about compromises. Do you consider lying about what I said, as you just did, a necessary evil acceptable when convenient, DSK? I haven't lied at all. You however have not only lied but also contradicted yourself a number of times. Why is that necessary to defend your boat? ... Do you have no self-respect whatsoever, DSK? Of course. I also have a lot of fun sailing, only not on a Mac 26 M or X. I am glad you enjoy sailing your boat. That's what it should be all about. DSK |
#5
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![]() DSK wrote: In other words, the boat is ballasted with a lot of mass far forward, as Jeff was contending earlier. JimC wrote: I never stated that the ballast mass is "far forward", DSK, and I don't think Jeff did either. If Jeff didn't, then why were you arguing with him over that exact point? Jeff had said that the ballast extended the entire length of the boat. It doesn't, and the ballast tank itself extends about the same distance forwardly and rearwardly from amidships. You need to remember that the ballast tank is tapered (both vertically and laterally) as it approaches the bow. Thus, the largest volume (and greatest mass) of ballast is concentrated amidships, slightly behind the mast. ... As to the moment of inertia during pitching, the motor, after all, is about the same weight as a crew member A very very large & well-fed crew member. ... and though its slightly aft of the cockpit In other words, it is as far aft as it can be, and still be part of the boat. .... its weight (mass) is not a great factor, as some of your buddies claim. (As previously stated: "I doubt seriously that the weight of the motor is a major factor.") Whoever stated that is an idiot. It's 200+ pounds at the farthest aft extremity of the boat. You want to claim this doesn't affect pitching moment "very much" whereas knowledgable sailors know that weight in the far ends of the boat is bad for steering & worse for pitching. Not a "major factor?" Sure thing DSK. - Whatever you say. The motor is about a foot behind the skipper's seat, so I'm sure that must create lots and lots of problems. The Mac is built with a wide hull, extending from amidships to the stern. - It's not a canoe hull, and it doesn't taper toward the stern as much as most boats do. Pitching isn't a problem, Ganz. Between the ballast far forward and the engine wieght far aft, it's hard to imagine a worse set-up for good sailing performance. Actually, of course, the ballast is centered slightly behind amidships, as already discussed. Additionally, there is several hundred pounds of fixed ballast amidships. In a boat such as the 26M with wide hull, 250 lb., is of little consequence. Yeah, I bet you can carry it with one hand. "Of little consequence" except for the boat's poor steering & worse pitching. Really? And what's your experience sailing the 26M? How many hours? It's always interesting to me that those who are the most adamant in their condemnation of the boat are the very ones who have never sailed one. Does the weight of the keel affect pointing? Funny, I always thought that had to do with the basic rig design... aspect ratio, sheeting base, etc etc... keel foil configuration plays into it somewhat I'm sure, but how does the wind know (and why would it care) about the weight of the keel? A conventional boat with deep, heavily weighted keel can stand up to more wind than the Mac before reefing, permitting a greater forward force on the boat than mine. Thus, the conventional boat can generally carry more sail, proportionally, and sail faster. As you probably know, a weighted keel positioned five or six feet below the hull entails more leverage Which does *what* exactly, for POINTING? Please explain. A boat with heavy weighted keel remains relatively upright even with lots of sail out, it can therefore be sailed faster upwind, and can point higher. Without the weighted keel,the boat tends to heel to a greater extent, requiring reefing in earlier, and to a greater extent, thus lessening it's forward speed while pointing. I'm not saying that the Mac doesn't sail well upwind, but it doesn't sail as well upwind as larger, heavier boats. In a boat without sufficient ballast, the boat develops weather helm, and it can't sail very well if pointing directly into the wind. .... provides a more efficient righting moment than the same weight of ballast,particularly water ballast, positioned within the hull. Why "particularly" water ballast? Does gravity care if a ton of ballast is water or lead or feathers? Yes, actually it cares a lot, DSK. - Because if the ballast is a ton of lead, which of course is substantially denser than water, the ballast will be substantially smaller than water ballast of the same mass. Therefore, its center of mass can be positioned lower in the hull. .... For its size, it a deep, weighted keel is more efficient in keeping the boat in a nearly upright position as winds increase, permitting more efficient translation of the force of the wind into forwardly directioned forces. That may help it's speed, but how will it affect the boat's pointing? As previously discussed, if the boat heels excessively because of insufficient ballast, it would tend to round up into the wind and loose speed. Boats with deep, heavy keels are less susceptible to the problem. (Incidentally, DSK, it seems to me that, instead of making me prove in infinite detail why the Macs don't point as well, you ought to jump on this as a negative factor in the Mac. - Whose side are you on anyway?) ... The aspect ration of the keel is, of course, also a factor in preventing lateral "sliding" of the boat, No it isn't. The aspect ratio is a factor in the expected lift/drag ratio of the foil. The total amount of lift generated by the foil determines the leeway or lateral sliding of the boat. I'll agree with you on that one. .... and the Mac 26M has a retractable dagger board that is quite narrow. Meaning what? It helps the boat point higher. You started out to explain pointing, and so far you've fumbled around in the dark in left field. You *almost* mentioned something that might be related to pointing, but you got it worng anyway. Sorry DSK. But it's still lots of fun to sail. ... To compensate for the relative inefficiency of the water ballast as compared with a heavy,weighted keel, the Mac has a total ballast sufficiently large to keep the boat upright. After years of mods and improvements, the current model, with appropriate reefing, sails ratehr well in pretty heavy weather. (For example, mine was heeling at only 20 degrees Saturday in 15 knot winds, with the first reef taken in.) And what was your VMG to windward? Are you talking about velocity over ground? - Around 6 knots or so with the main and jib reefed. - I was sailing solo, and didn't want to let it heel more than around 25 degrees. Best speed on a reach? If the wind is strong enough to reef, then you should be able to plane. You say the boat sails rather well, my observation (many times over) is that they sail poorly. Almost any decent sailboat will beat them downwind and a potting shed will beat them upwind. Once again, DSK, I didn't buy the Mac because I wanted to race it. - I bought it to enjoy sailing, cruising, etc. How many times do I have to repeat it? If all you are interested in is "beating" other boats, you have a ****-poor understanding of the joys of sailing IMHO. Are you tacitly admitting that Mac-26Ms don't sail to windward very well? We already know that's true of the M26X. No I'm not tacitly admitting anything. I'm openly stating (once again) that they don't sail to windward as well as conventional sailboats with weighted keels. It's one of the compromises of the particular design. So... we can agree it sucks at sailing to windward. Nope. It doesn't suck sailing to windward. But it doesn't do as well as some others. Do you think perhaps the weight of the motor... and the huge flat aft sections necessary to float it... have anything to do with that? I've had mine two years, DSK, and so far haven't seen any "huge, flat aft section," DSK. Where exactly is it? I'll remember that the next time I'm racing, DSK. But actually, I didn't buy the Mac with that in mind. I bought it to enjoy the overall sailing experience. Actually, if you're reefing & heeling & all that stuff, it must be almost the same as sailing.You mean, the experience of sitting on a boat with sails up? Pity you need that huge motor to actually go anywhere. BTW many sailboats will go faster than 13 knots. I'm aware of some that will, but most don't do it very often. Or were you talking about going down hill off a wave? ... Rather, it's the compromises relating to the internal ballast, trailerable hull, and lack of weighted keel. (The metactric effect.) Please explain. I know about metacentric height, but have never heard of "the metacentric effect." The metacentric height is considered the distance between the center of gravity and the metacenter. By "metacentric effect", I was referring to the fact that the righting force is proportional to the metacentric height times the sine of the angle of heel. Thus, a conventional boat, with weighted keel low in the water, would have a lower center of gravity than the Mac and would therefor tend to be less tender. Good, but not quite right. The metacenter is figured as height above the waterline. A lower center of gravity doesn't affect the metacenter at all, it is strictly a function of hull shape. Actually, I think you may be wrong there. I'll try to get the article I was quoting. Shall I explain curves of righting moment? It's a key to understanding how different boats sail differently... nah, maybe some other time. For now, let's just say that there are effectively 2 forces producing righting moment, one is the hull shape which produces initial stability... how tender the boat feels when you step onto the gun'l from the dock, for example... and the other is reserve stability, which is affected by how low & heavy the ballast is, and produces righting moment at high angles of heel. ... Again, the Mac 26M does entail compromises, but after a number of years of development and modifications, it does the job. (If it didn't, I would have capsized Saturday in the 15-knot winds instead of sailing along with a 20 degree heel.- Right? The fact that the boat doesn't fall over helplessly in 15 knot winds is good, agreed. No, the 2M isn't flat aft. I guess it depends on what you call "flat." http://www.improb.com/airchives/pape...i3/kansas.html The hull of the 26M has a sharp V contour extending forwardly from the stern, substantially greater than that of the 26X. Perhaps you were confusing it with the older model. ... In contrast with your statement, it does plane easily and smoothly. Then why won't it plane under sail? Lots and lots and lots of boats plane under sail. It has been known how to design sailboat hulls & rigs to plane since 1928. How the heck modern can the Mac 26 M be if it doesn't incorporate this concept? Lots of boats plane under sail? - Does that include lots of family cruisers with standing headroom, queen-sized berth, high freeboard, etc.? And just where did I say that the Mac 26M is a "sooper-dooper hot performing sailing machine", or anything of the kind? Well, lately, you've been admitting that it's slow. But hey, that's of no consequence, just like the increased hobby-horsing due to the weight of the engine on the transom. And you have sailed the 26M how many times? ... I've said that the Mac 26M is fun to sail, but I have consistently stated that it doesn't sail or point as well as a large displacement boat. Or a small one. ... Instead of saying the Mac is a great sailing machine, I've said that it has limitations and disadvantages when compared with conventional vessels. It's all about compromises. Do you consider lying about what I said, as you just did, a necessary evil acceptable when convenient, DSK? I haven't lied at all. You however have not only lied but also contradicted yourself a number of times. You didn't lie, DSK. That in itself is another lie. - I have never said that the 26M was a "sooper-dooper sailing machine." I have consistently admitted that it entails compromises. Why is that necessary to defend your boat? Because the discussions have become too one-sided and need a little balance. Also, quite frankly, I get a lot of enjoyment seeing some of the Mac-Bashers becoming increasingly frustrated and embarrassed at not being able to put me down. Those condemning the Macs on this ng in the past have been ridiculously ill-informed. (And, once more, it's nearly always those who have never sailed a 26M who are the most critical and the most dogmatic in their opinions.) So I intend to continue providing some balance to the discussions from time to time, as my schedule permits. ... Do you have no self-respect whatsoever, DSK? Of course. I also have a lot of fun sailing, only not on a Mac 26 M or X. I am glad you enjoy sailing your boat. That's what it should be all about. I also enjoy sailing other boats, DSK. Jim |
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![]() DSK wrote: In other words, the boat is ballasted with a lot of mass far forward, as Jeff was contending earlier. JimC wrote: I never stated that the ballast mass is "far forward", DSK, and I don't think Jeff did either. If Jeff didn't, then why were you arguing with him over that exact point? Jeff had said that the ballast extended the entire length of the boat. It doesn't, and the ballast tank itself extends about the same distance forwardly and rearwardly from slightly forward of amidships. You need to remember that the ballast tank is tapered (both vertically and laterally) as it approaches the bow. Thus, their is very little mass near the bow, and the largest volume (and greatest mass) of ballast is concentrated forward of amidships. ... As to the moment of inertia during pitching, the motor, after all, is about the same weight as a crew member A very very large & well-fed crew member. By way of perspective, there may be several crew members and/or guests in the cockpit, weighing far more than the motor. Though the motor is slightly to the rear of the cockpit, the weight of the crew/skipper/guests (when guests/crew are onboard) is by far the greatest weight factor. And the boat is designed to be balanced and sail well with such a load. ... and though its slightly aft of the cockpit In other words, it is as far aft as it can be, and still be part of the boat. .... its weight (mass) is not a great factor, as some of your buddies claim. (As previously stated: "I doubt seriously that the weight of the motor is a major factor.") Whoever stated that is an idiot. It's 200+ pounds at the farthest aft extremity of the boat. You want to claim this doesn't affect pitching moment "very much" whereas knowledgable sailors know that weight in the far ends of the boat is bad for steering & worse for pitching. Not a "major factor?" Sure thing DSK. - Whatever you say. The motor is about a foot behind the skipper's seat, so I'm sure that must create lots and lots of problems. In fact, the Mac is built with a wide (but not "huge", flat bottomed") hull, extending from amidships to the stern. - It's not a canoe hull, and it doesn't taper toward the stern as in the case of some boats. Pitching isn't a problem, Ganz. Between the ballast far forward and the engine wieght far aft, it's hard to imagine a worse set-up for good sailing performance. Actually, of course, the ballast is centered slightly forward of amidships, as already discussed. Additionally, there is several hundred pounds of fixed ballast amidships. In a boat such as the 26M with wide hull, 250 lb., is of little consequence. Yeah, I bet you can carry it with one hand. "Of little consequence" except for the boat's poor steering & worse pitching. Really? And what's your experience sailing the 26M? How many hours? It's always interesting to me that those who are the most adamant in their condemnation of the boat are the very ones who have never sailed one. Does the weight of the keel affect pointing? Funny, I always thought that had to do with the basic rig design... aspect ratio, sheeting base, etc etc... keel foil configuration plays into it somewhat I'm sure, but how does the wind know (and why would it care) about the weight of the keel? A conventional boat with deep, heavily weighted keel can stand up to more wind than the Mac before reefing, and since more sail can be let out proportionally to the size of the boat, the conventional boat has a greater forward force vector than mine. Thus, the conventional boat can generally carry more sail, proportionally, and sail faster upwind. Also, since the conventional boat can stand up (more vertically) to the wind, the keel serves more efficiently to minimize lateral movement of the boat, keeping it on a straight, upwind course. As you probably know, a weighted keel positioned five or six feet below the hull entails more leverage Which does *what* exactly, for POINTING? Please explain. A boat with heavy weighted keel remains relatively upright even with lots of sail out, it can therefore be sailed faster upwind. Without the weighted keel,the boat tends to heel to a greater extent, requiring reefing in earlier and to a greater extent, thus lessening it's forward speed while pointing. I'm not saying that the Mac doesn't sail well upwind, but it doesn't sail as well upwind as larger, heavier boats. In a boat without sufficient ballast, the boat heels and develops weather helm, forcing it into the wind. It can't sail upwind very well if pointing directly into the wind. .... provides a more efficient righting moment than the same weight of ballast,particularly water ballast, positioned within the hull. Why "particularly" water ballast? Does gravity care if a ton of ballast is water or lead or feathers? Yes, actually it cares a lot, DSK. - Because if the ballast is a ton of lead, which of course is substantially denser than water, the necessary ballast will be substantially smaller than water ballast of the same mass. Therefore, it can be positioned lower in the hull, making it more efficient, in that the center of mass is lower (and the "lever arm" is longer). Or, if desired, more lead ballast can be used within a given space, for providing still more stability. .... For its size, it a deep, weighted keel is more efficient in keeping the boat in a nearly upright position as winds increase, permitting more efficient translation of the force of the wind into forwardly directioned forces. That may help it's speed, but how will it affect the boat's pointing? As previously discussed, if the boat heels excessively because of insufficient ballast, it would tend to round up into the wind and loose speed. Boats with deep, heavy keels are less susceptible to the problem. (Incidentally, DSK, it seems to me that, instead of making me prove in infinite detail why the Macs don't point as well, you ought to jump on this as a negative factor in the Mac that I have acknowledged. - Whose side are you on anyway?) ... The aspect ration of the keel is, of course, also a factor in preventing lateral "sliding" of the boat, No it isn't. The aspect ratio is a factor in the expected lift/drag ratio of the foil. The total amount of lift generated by the foil determines the leeway or lateral sliding of the boat. I'll agree with you on that one. The narrow keel provides greater maneuverability, but not more lift. .... and the Mac 26M has a retractable dagger board that is quite narrow. Meaning what? It helps the boat maneuver more efficiently. You started out to explain pointing, and so far you've fumbled around in the dark in left field. You *almost* mentioned something that might be related to pointing, but you got it worng anyway. Sorry to disapoint you DSK. But the boat is still lots of fun to sail. ... To compensate for the relative inefficiency of the water ballast as compared with a heavy,weighted keel, the Mac has a total ballast sufficiently large to keep the boat upright. After years of mods and improvements, the current model, with appropriate reefing, sails well in pretty heavy weather. (For example, mine was heeling at only 20 degrees Saturday in 15 knot winds, with the first reef taken in.) And what was your VMG to windward? I'm assuming you talking about velocity over ground? - Around 6 knots or so with the main and jib reefed. - I was sailing solo, and didn't want to let it heel more than around 25 degrees. Best speed on a reach? If the wind is strong enough to reef, then you should be able to plane. You say the boat sails rather well, my observation (many times over) is that they sail poorly. Almost any decent sailboat will beat them downwind and a potting shed will beat them upwind. Once again, DSK, I didn't buy the Mac because I wanted to race it. - I bought it to enjoy sailing, cruising, etc. How many times do I have to repeat that? If all you are interested in is "beating" other boats, you have a ****-poor understanding of the joys of sailing IMHO. Are you tacitly admitting that Mac-26Ms don't sail to windward very well? We already know that's true of the M26X. No I'm not tacitly admitting anything. I'm stating opently (once again) that they don't sail to windward as well as conventional sailboats with weighted keels. It's one of the compromises of the design. So... we can agree it sucks at sailing to windward. Nope. It doesn't suck sailing to windward. But it doesn't do as well as some others. Do you think perhaps the weight of the motor... and the huge flat aft sections necessary to float it... have anything to do with that? I've had mine two years, DSK, and so far I haven't seen any "huge, flat aft section," Where exactly is it? Actually, if you're reefing & heeling & all that stuff, it must be almost the same as sailing.You mean, the experience of sitting on a boat with sails up? Pity you need that huge motor to actually go anywhere. Cute DSK. But rather childish. - And, you have sailed the 26M how many times? BTW many sailboats will go faster than 13 knots. I'm aware of some that will, but most don't do it very often. Or were you talking about going down off a wave? ... Rather, it's the compromises relating to the internal ballast, trailerable hull, and lack of weighted keel. (The metactric effect.) Please explain. I know about metacentric height, but have never heard of "the metacentric effect." The metacentric height is considered the distance between the center of gravity and the metacenter. By "metacentric effect", I was referring to the fact that the righting force is proportional to the metacentric height times the sine of the angle of heel. Thus, a conventional boat, with weighted keel low in the water, would have a lower center of gravity than the Mac and would therefor tend to be less tender. Good, but not quite right. The metacenter is figured as height above the waterline. A lower center of gravity doesn't affect the metacenter at all, it is strictly a function of hull shape. Actually, I think you may be wrong there. I'll try to get the materials I was quoting. Shall I explain curves of righting moment? It's a key to understanding how different boats sail differently... nah, maybe some other time. For now, let's just say that there are effectively 2 forces producing righting moment, one is the hull shape which produces initial stability... how tender the boat feels when you step onto the gun'l from the dock, for example... and the other is reserve stability, which is affected by how low & heavy the ballast is, and produces righting moment at high angles of heel. ... Again, the Mac 26M does entail compromises, but after a number of years of development and modifications, it does the job. (If it didn't, I would have capsized Saturday in the 15-knot winds instead of sailing along with a 20 degree heel.- Right? The fact that the boat doesn't fall over helplessly in 15 knot winds is good, agreed. No, the 2M isn't flat aft. I guess it depends on what you call "flat." http://www.improb.com/airchives/pape...i3/kansas.html The hull of the 26M has a sharp V contour extending forwardly from the stern, substantially greater than that of the 26X. Perhaps you were confusing it with the older model. ... In contrast with your statement, it does plane easily and smoothly. Then why won't it plane under sail? Lots and lots and lots of boats plane under sail. It has been known how to design sailboat hulls & rigs to plane since 1928. How the heck modern can the Mac 26 M be if it doesn't incorporate this concept? Lots of boats plane under sail? - Does that include lots of family cruisers with standing headroom, queen-sized berth, high freeboard, capable of being stored on a trailer, etc.? - I once had a Lido that would plane. It didn't have a cabin, or a head, or a galley, however. And just where did I say that the Mac 26M is a "sooper-dooper hot performing sailing machine", or anything of the kind? Well, lately, you've been admitting that it's slow. But hey, that's of no consequence, just like the increased hobby-horsing due to the weight of the engine on the transom. And you have sailed the 26M how many times? ... I've said that the Mac 26M is fun to sail, but I have consistently stated that it doesn't sail or point as well as a large displacement boat. Or a small one. ... Instead of saying the Mac is a great sailing machine, I've said that it has limitations and disadvantages when compared with conventional vessels. It's all about compromises. Do you consider lying about what I said, as you just did, a necessary evil acceptable when convenient, DSK? I haven't lied at all. You however have not only lied but also contradicted yourself a number of times. You didn't lie, DSK? That in itself is another lie. - I have never said that the 26M was a "sooper-dooper sailing machine." I have consistently admitted that it entails compromises. - Incidentally, could you please cite ten incidences in which I have lied? Or if you can't find ten, how about five? Two? Why is that necessary to defend your boat? Because discussions of the Macs on this ng have been too one-sided and need a little balance. There is also the matter of the possible damage to the reputation of the MacGregor company, one of the great manufacturers of modern sailing craft caused by comments from people who, for the most part, have never sailed one and don't know what they are talking about. Also, quite frankly, I get a lot of enjoyment seeing some of the Mac-Bashers becoming increasingly frustrated and embarrassed at not being able to put me down. Those condemning the Macs on this ng in the past have been ridiculously ill-informed. (And, once more, it's nearly always those who have never sailed a 26M who are the most critical and the most dogmatic in their opinions.) So I intend to continue providing some balance to the discussions from time to time, as my schedule permits. ... Do you have no self-respect whatsoever, DSK? Of course. I also have a lot of fun sailing, only not on a Mac 26 M or X. I am glad you enjoy sailing your boat. That's what it should be all about. I also enjoy sailing other boats, DSK. Jim |
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JimC wrote:
And you have sailed the 26M how many times? The same number of times you have, judging by how well you've observed the boat's characteristics. However, I have not ridden in one with the big white flappy things up. DSK |
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![]() DSK wrote: JimC wrote: And you have sailed the 26M how many times? The same number of times you have, judging by how well you've observed the boat's characteristics. However, I have not ridden in one with the big white flappy things up. DSK Real cute Ganz. When you have sailed one, let me know. Jim |
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Ummm... I think you're getting befuddled. Doug wrote this... as much as I
would have liked to. :-) -- "j" ganz @@ www.sailnow.com "JimC" wrote in message . .. DSK wrote: JimC wrote: And you have sailed the 26M how many times? The same number of times you have, judging by how well you've observed the boat's characteristics. However, I have not ridden in one with the big white flappy things up. DSK Real cute Ganz. When you have sailed one, let me know. Jim |
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