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#201
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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 |
#202
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Once again... Doug not I....
-- "j" ganz @@ www.sailnow.com "JimC" wrote in message ... DSK wrote: JimC wrote: Jeff, I don't have time to defend lawyers on this ng. Nobody has *that* much time JimC wrote: .... The boat is built to be balanced, under sail or power, with the motor and a typical crew in the cockpit. By "balance" I meant that the hull, motor, ballast, and sails work togther to cause the boat to to sail and motor as efficiently as possible under a variety of applications. In general, it sails and powers well, it doesn't "pitch" excessively, and it is fun to sail. But not as much fun as a boat that sails better. And you have sailed the 26M how many times, Ganz? What is pitching "excessively"? Enough to notice? Enough to cause ridicule by other sailors? Actually, I have sailed a number of different boats. I am familiar with the sailing characteristics of the Beneteaux 39, the O'Day 39, the Valiant 40, the Cal 32, and a number of others. I can assure you Ganz that "pitching" is not a problem on the Mac 26M. If the boat's moment of inertia is too high, then the boat sails slowly and pitches more than it would if the weights were closer to the hull's center of volume. In other words, the hull, motor, and ballast, are inherently flawed in design to enable the big heavy motor. Yes, but they aren't flawed. And, once more, how many times have you sailed the 26M? JimC wrote: The 26M is the result of years of development, feedback, and mods. It does a lot of things most sailboats can't do. It also doesn't do a few basic things that most sailboats do; and of things that most sailboats do well, it does poorly. And how many times have you sailed the 26M? How many hours? .... If serves the needs of most sailors, under the conditions experienced 90% of the time. Actually, it doesn't. If it did, it would probably be more popular. If popularity is a factor, then you lose. The Mac is one of the most popular boats ever built. .... It's relatively inexpensive, if you are willing to compare the costs of new boats to new boats, or used boats to used boats, and not compare the costs of 15 year old boats with that of a new Mac 26M similarly equipped. It's cheap compared to motorboats of similar cabin size. *That* is the key selling point, plus the bonus that trailerable motorboats of similar cabin room require a much heavier & more expensive towing vehicle. In this case, I tow and launch the boat with a conventional Mercury sedan. - No pickup needed. But I don't think that is the "key selling point." The key selling points include the fact that it's fun to sail, it's versatile, it's safe (including sufficient flotation to keep it afloat even if the hull is compromised, it can be used as a coastal sailor or power boat, it has five berths, it can float in one foot of water, it can motor out to a desired sailing area quickly, and motor back quickly, to permit more sailing time, it's dagger board, motor, and rudders can be adjusted as desired for particular sailing conditions, the ballast can be removed to reduce the weight of the boat for tailoring, it can be launched in very little water (in contrast to many "trailerable" boats), it rides low on the trailer, providing safer trailering, it includes a rotatable mast, permanent ballast plus removable water ballast, roomy cabin with standing headroom, etc., etc. Also, it's fun to sail. Jim And, (I almost forgot) it's a lot of fun to sail. If you're not picky. DSK |
#203
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![]() Jeff wrote: JimC wrote: And let me point out again, its not the weight, its the location. A 250 pound engine hanging off the stern contribute far more to the pitch moment than an inboard close to the center of the boat. Well, that's clear enough, and I agree. But once more, the boat is built to be balanced fore and aft with a motor and a crew in the cockpit. And it is. Totally irrelevant. Nope. It's actually quite relevant. The boat is built to be balanced, under sail or power, with the motor and a typical crew in the cockpit. By "balance" I meant that the hull, motor, ballast, and sails work togther to cause the boat to to sail and motor as efficiently as possible under a variety of applications. In general, it sails and powers well, it doesn't "pitch" excessively, and it is fun to sail. Nice backpedal. It clearly isn't what you meant the first few times around, but if you think it saves some face for you, so be it. Jeff, I have not wanted to get into the issue of weight distribution in detail, since you pretty well had your assed kicked all over the ng on that one. - Don't forget that you initially claimed that the ballast extends the full length of the boat, and that was a bad distribution of mass (and would tend to increase pitching movement). After carefully explaining to you what the Mac drawings were showing, and responding to numerous notes, you were finally forced to back off your original claims, and admit that, well, there wasn't a lot of ballast in the aft portions of the boat. You then claimed that the ballast extended all the way to the bow, so that was a problem also. - I then patiently explained that the ballast tank was pointed toward the bow and tapered BOTH VERTICALLY AND HORIZONTALLY as it approached the bow (as shown in the side sectional view and the cross-sections in the drawings you posted). Not making much headway on either of these points, you then started to become hyper and jump up and down about the fact that the ballast tank was near the forward end of the bow, and the motor was at the stern. - I then explained that the center of mass of the ballast tank (tapered forwardly and rearwardly) was actually just slightly forward of amidships, and the motor, while positioned at the stern, actually comprises only a relatively small portion of the weight near the stern. - The greatest weight factor being the skipper and crew and/or guests in the cockpit. Thus, although the motor is in the aft end of the boat, the crew/guests/skipper comprise a much greater mass factor at the aft end of the boat. Jeff, I've gone over this with you and patiently explained it to you a number of times, yet you refuse to acknowledge that you just didn't get it. I'm concluding that you thought you had a good "gotcha" to throw at me, but it turned out you didn't, and you just can't admit it to yourself or the ng. or you just showing what type of lawyer you really are. Obviously the boat was designed to float on its lines with full ballast and an engine. The issue is whether a different distribution of mass would lead to a boat that sails better. Yet you HAVE NO SUGGESTIONS WHATSOEVER as to how to improve the distribution of mass. - If a bad distribution of mass is a key problem (actually, it isn't, since the boat sails and motors steadily and exhibits no excessive pitching movement) then, at a minimum, you should be able to tell us where you would move the outboard and/or the ballast. - But you don't want to get into that one, do you Jeff? And just how would you redistribute the mass, Jeff? - Where would you move the outboard, and where would you move the ballast? I would not have designed this boat at all, so don't asked me have I might change it. All I wanted to do when I started this topic of discussion was to rationally consider how the different weight distribution affects stability and balance. But you wanted to turn this into something quite different. Nope. I responded to each of your points about weight distribution (see the above note), and then went on to further, related issues. The bottom line is that, if your theories were correct, the boat would pitch uncontrollably and bounce around in heavy weather. - But it doesn't. The 26M is the result of years of development, feedback, and mods. It does a lot of things most sailboats can't do. If serves the needs of most sailors, under the conditions experienced 90% of the time. That's nonsense!!! Really? And you have sailed the 26m how many times?????? It's relatively inexpensive, debatable if you are willing to compare the costs of new boats to new boats, or used boats to used boats, and not compare the costs of 15 year old boats with that of a new Mac 26M similarly equipped. So why do they seem to depreciate twice as fast as other boats? Where are your stats on that one, Jeff???? And, (I almost forgot) it's a lot of fun to sail. only for those with low standards. And you have sailed the 26M how many times???? Maybe it would. But it's still a lot of fun to sail as it is. (I'm repeating myself, but isn't that the point, after all? Is it? Little children think picking their nose is fun, is that your standard? You fight every detail tooth and nail, As one of the few on this ng willing to defend the Macs, I'll continue to do my part to ensure that Mac discussions have at least a semblance of balance and accuracy. If I'm right, I'll try provide a good, but balanced and fair defense of the Mac. even when you know you're wrong, and then you say "it doesn't matter that I'm lying because I'm having fun." You may disagree with my conclusions, Jeff, but tell me where I have lied to you or anyone else? (Paying attention to what I actually said in several notes, for a change, and ignoring for a moment WHAT YOU INTERPRETED as the meaning of portions of some of my comments.) Jeff, which are the top ten most egregious lies I have posted on the ng? Or, failing that, the top five? --- Two, maybe? Jeff, we may have differing opinions, and you seem to have confused your own opinions as facts, but would you please name the more egregious instances of my lying? Perhaps you could list the top ten instances? Being a clever lawyer, you word things so that they will be taken one way, but you can claim you said something different. Your comment above about balance was one such example. See comments above. The bottom line is that you simply misunderstood the Mac drawings. The "double liner" discussion is another. See prior comments. - I NEVER said that the ballast tank protected the entire boat. - That was another of your own, rather convenient "gotcha" interpretations. Your claim that the outboard is much lighter than a diesel is another. I'm claiming that the outboard is lighter than a diesel with sufficient power for the Mac when all the associated components, including the drive shaft and supporting structures are included. Also, I seriously doubt that a small (e.g., 10-15 hp motor would be sufficient to drive the Mac through heavy chop and adverse winds. Your claim that the ballast is very close to the center is yet another. It is. - Your problem is that you didn't understand the drawings. They question is, Jim, when have you been completely truthful? Although I don't claim omniscience, I have certainly endeavored to be truthful and to present a balanced response and evaluation of the Mac. For example, I have noted a number of limitations inherent with the boat. - I have acknowledged that it normally doesn't sail as fast or point as high as most conventional boats with weighted keels. I have acknowledged that it isn't suitable for extended blue water crossings, etc. I have acknowledged that it is lightly built. - - - Why haven't you complemented me for being upfront concerning THESE issues, Jeff? The boat is fast enough to be fun to sail, Jeff. It's not as fast as some other boats, but it's still fun to sail. - Isn't that the important factor.? (Actually, I wasn't having too much problem keeping up with some, though not all, of the larger boats on my last cruise.) All boats are fun to sail. That's not the point. It is to me. You make lots of claims, and then try to write them off by saying, "but its fun to sail." What's your point? Because that's the key factor, from my perspective. However, I don't think I agree that a typical diesel, with generator, fuel pump, filters, prop shaft, etc., would weigh about the same as a modern outboard. - Any stats on that one? I thought I just gave one. The weight of a 15 Hp Yanmar, including everything (alternator, pumps, filter) except the shaft and prop is 249 lbs. Clearly one might add another fuel filter or water filter, and the muffler weighs a few pounds (mine are plastic) but all of this is only a few pounds, and then your outboard also has a few extra bits and pieces not included in its base weight. Also, since the diesel generates almost twice the power from a pound of fuel, one can claim a huge weight advantage on that front. You're omitting some items, such as the drive shaft, shaft bushing assembly, supporting framework in the boat, etc. You're also comparing a 15 hp motor with a 50 hp motor, and you're not addressing the fact that the Mac requires lots of power to keep in on course in heavy weather, chop, winds, etc. That's more than my 50 hp weighs. Also, add the weight of the drive shaft, the drive shaft bushings, the mounting hardware, the reinforcements to the hull supporting the motor, etc. Yes, we know that the mac has no reinforcements to the hull supporting its motor. You really are intent on showing how lawyers lie, aren't you? It has enough. You made the claim that a diesel is much heavier than an outboard, and that simply isn't true. Further, the issue has nothing to do with the possible difference of 20 pounds, it has to do with the distribution. Re weight distribution, see my comments above. - I can understand why you would be embarrassed about that one and prefer that we not discuss it again. As to the relative weight, it seems that you want us to accept your personal opinions about how much the typical diesel engine for a small sailboat weighs from your I was quoting from the Yanmar specs, using the most frequently spec'd diesel for small sailboats. Originally I mentioned to two cylinder version, because you had asked what someone had in their boat. But for one as light as the Mac, a one cylinder could do. Having powered the Mac 26M in somewhat heavy weather, I don't think a small engine will do the job Jeff. It's a large, light weight boat with high freeboard and no weighted keel, and it needs lots of power to keep it one course. Of course, most Mac skippers appreciate the fact that a 50+ hp motor provides a lot of conveniences and enhances the versatility of the boat. (Incidentally, most Mac buyers seem initially to think that they don't want a larger engine, but they eventually come to appreciate the advantages available with the larger engine.) single example, which omitted the necessary weight of the drive shaft, the mounting, etc.. I mentioned to driver shaft. However, the weight on that could vary a lot, and its so low it could be considered ballast. From your note, it seems that you are saying that I should just shut up and accept your propaganda based on that (one) example. - Perhaps it would clarify things if you provided some stats about the weight of several typical diesel installations on smaller boats. (Including ALL associated components, including drive shaft, cooling system, through-hull components, fuel and water filters, pumps, mounting structures, controls, fuel tanks, etc.) More lies! I mentioned that the weight for a diesel doesn't include several items, including the drive shaft. It does include most of the others you've mentioned - fuel filter, cooling system, pumps, alternators etc. Some of what you claim are needed for your installation. Are you trying to claim there is no mounting hardware or reinforcement, no controls, no fuel tanks? How about the fact that the gas engine needs twice the fuel? First, although the transom is sufficiently strong to support the motor, I don't see any additional support structures for the motor. The "mounting hardware" consists of some bolts, washers, and the like. Secondly, there are controls, consisting largely of a tubular connecting bar and cables extending to the steering mechanism. - Again, nothing that would add any substantial mass, unless you consider the small steering wheel to be "massive." The fuel tank is a 10-gal. plastic tank. - Again, only a few pounds of "mass." Next, regarding the cost of all that fuel, we get around 3 - 5 miles per gallon at plaining speeds, and I have probably spent about $25 on gas during the past six months. Of course, as an attorney, I have lots of money to spend on all that gas, so it really isn't a major factor. (That's a joke, Jeff. Of course.) Actually, I spend most of the time sailing, not motoring. Also, because of work assignments last Summer and Fall I was limited in how much I was able to take the boat out. Still, gas costs haven't been a major factor. And of course, the primary issue here is that the weight of the diesel is well forward, while the outboard is as far aft as possible. And BTW, the diesel appropriate for a boat as light as yours would be a single cylinder, which would weigh just about the same as your outboard. Care to provide specs on a few examples, Jeff, along with their gross weight? The Yanmar 1GM is 179 pounds with transmission. And, as mentioned above, remember that the Mac, with its high freeboard and light weight, needs substantial power to get through chop and adverse wind conditions, to stay on course in extreme weather, and to dock efficiently. - A small diesel isn't going to cut it. Also, a small diesel isn't going to get the boat on a plane either. - No more quick runs back to the marina, no quick passages to desired skiing areas, no water tubing for the kids, etc.) Hey, you're the one who brought this up. You claimed your engine was much lighter than the diesel on most similarly sized sailboats. I pointed out you're wrong. Jeff, in reviewing my note and your responses, I now think I was wrong in saying the weight of my 50 hp outboard was "much lighter" than a typical diesel on most sailboats in the 27 - 29 ft range. I think it is somewhat lighter when all factors are considered, and it's more powerful, but my statement as written was apparently incorrect. - I had come to a (mistaken) judgment from working with larger diesels on larger boats. Still, my statement about the safety factors entailed in having a fairly powerful motor on the Mac is accurate, IMO. - For example, when I had the boat out last, as mentioned earlier, we had a rather substantial incoming tide and headwind, the waves were breaking against us all the way out to the sailing area, and there was a lot of traffic, with wakes. The Mac is lightweight and has a fairly large sideboard area. - If I had had a 10 - 15 hp motor as is often the case for boats of this size, I don't think I could have kept it on track within the channel all the way out. Also, I would not have been able to keep up with the other traffic going out, which causes further problems. The reserve power is also a safety factor in the event of inclement weather, tides, etc., out in the Bay or beyond. Obviously, a 40 - 50 hp diesel would weigh substantially more. And I also agree that your boat is more efficient using the smaller diesel, and that the positioning of the diesel is better for achieving a low cog. - It does take up more interior space than my outboard. Once again, Jeff, as to the weights of the 50 hp outboard and your 15 hp diesel, you're right, and I was wrong. My purpose in these Mac discussions is not to distort the facts or win arguments, but rather to do my part from time to time in contributing to a more balanced discussion. Jim |
#204
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![]() Jeff wrote: JimC wrote: Jeff, this note included your misleading comments on a number of subjects, and I have tried to address most of them. Because of your lengthy comments, the response is also lengthy. - Perhaps it would be more helpful if you would limit each response (if you choose to respond) to one or two subjects per note. Jim, not a single one of my claims is misleading. Yours, on the other hand, speak volumes about your ethics. Jeff wrote: Jeff wrote: It really amazes me how you can shift positions to suit your need. Is that what you learn in lawyer school? Sure thing Jeff. - Of course, it's clear that you cherry-picked and I love that expression "cherry-picked"! I think that would be a good defense - "Your Honor, the prosecution is just cherry-picking. What about the 6 billion people that my client didn't kill that night?" By "cherry-picking", I refer to the fact that you keep repeating the statement quoted below, but you totally ignore the other statements I made during that discussion in which I said that the warnings, Looks like you erased all my additional remarks POSTED IN THAT DISCUSSION stating that the warnings should NOT be ignored. ... Why would you do a pitiful, sneaky thing like that Jeff?? You talk about layers' ethics. - What about your own??? Sorry, I really don't understand your point. You claimed that some of the warnings made can be ignored, by saying there were analogous to warnings to wear the seatbelt on an exercise machine. particularly those relating to sailing the boat without ballast, should be observed. - You also ignore the instructions IN THE MAC OWNERS' MANUAL about motoring without the ballast. - Cherry-picking at it's best, Jeff. I'm not cherry picking, you're the one who says that some warnings can be ignored. You are certainly cherry picking. - You quote my initial statement about lawyers being involved, but you erase and ignore my subsequent statements explaing in detail what I thought about the Mac warnings. (And as far as my own practices, I have never sailed or motored without the ballast.) You are apparently doing your best to look for comments of mine you can isolate and use for "gotchas", and you apparently have no ethical qualms whatsoever about deliberately cutting out my subsequent statements posted during that discussion. Shame, Shame, Shame. - Pitiful! - Here's my further discussion (which you conveniently ignore) of the Mac warnings, provided to you over a year ago: What was next, Jeff? - - -Is this another "clip" of material you don't want included in the current note, Jeff? Shame, shame shame. "When, exactly, did I state that "the warnings can be ignored?" (Helpful hint. - I didn't.) Gee, how many times do I have to repost your comments? I post them, you delete them. Over and over. - What I said was that it should be understood that the were written partially for legal purposes, for protecting MacGregor from legal action. THAT DOES NOT MEAN that the warnings should simply be ignored out of hand. You said: "Jeff, have you had many dealings with corporate attorneys? Or tort lawyers? If you had, you would recognize that these warnings, if taken literally, are something like the warnings posted in our health center warning us to be sure to wear our seat belt when using the Nautilus weight training equipment. Or, like the long list of warnings you get when you purchase any electrical appliance, audio equipment, etc. " Everyone, except perhaps a lying lawyer, would understand that to mean that the warnings can be ignored. Are you telling me that you assume everyone wears a seatbelt on the exercise machine? Are you saying that everyone who reads that should be thinking "Yes, I always wear the seatbelt on the exercise machine so these must be real serious warnings"??? Do you really expect anyone to buy that Jim? snip lawyer talk that everyone knows can be ignored Interesting "snip" Jeff. You obviously don't want to remind anyone that I posted several notes during that discussion explaining in detail my interpretation of the MacGregor manual (which included BOTH the warning against powering or sailing without ballast, AND ALSO an explanation of how to motor without ballast). So you censor those statements. Shame, shame shame! Sad, Jeff. Pitiful. Jeff,- How many more times are you going to regurgitate the same illogical argument? blah blah blah. You're arguing this as a lawyer. This is why lawyers are considered by many to be the Scum of the Earth. Is that what you are, Jim? Everyone reading this knows you're digging this hole deeper and deeper with everything you say. And yet you continue. Did they teach you that if you lie often enough someone will believe you? I made the point that the Mac comes with a long list of warnings not found on other boats, and possibly not well understood by novice boaters. You've been going around in circles now for years claiming that first that these warnings can be ignored because they're just lawyer talk, then saying they can't be ignored, then saying that they're only there to protect from law suits. Nope, I never said they could be ignored merely because they included legal cya aspects. - See my own further comments about the subject posted a year ago in the same discussion, partially repeated in my note above (which you so conveniently continue to ignore.) The bottom line is that what I said in the beginning still holds. substantially misrepresented what I said. I never said that the warnings that come with a Mac can be ignored, and you know it. Your comment was: "Jeff, have you had many dealings with corporate attorneys? Or tort lawyers? If you had, you would recognize that these warnings, if taken literally, are something like the warnings posted in our health center warning us to be sure to wear our seat belt when using the Nautilus weight training equipment. Or, like the long list of warnings you get when you purchase any electrical appliance, audio equipment, etc. " You've tried to "un-ring this bell" many times, but I think everyone here understands what you meant. ... In other words, I didn't say what you said I did. And I didn't make the statement you wish I had said. And you know it. Once more, Jeff, where did I say that those warnings could be ignored? Once more, Jim, no one is buying it. (In other words, I didn't say they could be innored, and you can't find any such statement.) You said: "Jeff, have you had many dealings with corporate attorneys? Or tort lawyers? If you had, you would recognize that these warnings, if taken literally, are something like the warnings posted in our health center warning us to be sure to wear our seat belt when using the Nautilus weight training equipment. Or, like the long list of warnings you get when you purchase any electrical appliance, audio equipment, etc. " Gee, this is easy. You're really a masochist. Or do you think ... well, I don't know what you think. Any reasonable person would say, "Ooops, I made a mistake, better not go there any more." Anyone who reads this knows what you said, why one Earth would you deny it??? In other words, I didn't make the statement you wish I had said. Is that about the size of it Jeff? ... Jeff, I asked you whether you thought MacGregors' attorneys were not involved with the inclusion of those warnings. - You never answered me. - Why? What's the point? How is it relevant? Are you claiming that the warnings can be ignored because a lawyer wrote them? Are you claiming lawyers are liars? Jeff, here's some of the statements you so carefully omitted from your quotes of my previous comments: "At page 1 of the owners manual for the 26M it states IN BOLD, UNDERLINED PRINT, that THE BALLAST TANK SHOULD BE FULL WHEN EITHER POWERING OR SAILING. This warning clearly states that the tank should be full under all circumstances." "But on the same page, the manual also states that: "THERE MAY BE TIMES WHEN YOU WISH TO OPERATE THE BOAT WITH AN EMPTY BALLAST TANK For example, when puling a water skier, when trying to conserve fuel, when a faster ride is desired, ..." Obviously, when read in context, the first statement is meant as a general warning, with apparent legal overtones, which is expected to be read in light of the second section dealing with operation of the boat WITHOUT the water ballast, under certain conditions. - Once again, Jeff, the fact that the initial warning may have been inserted at least in part with legal considerations in mind, and the fact that I suspect it was, DOES NOT mean that it should not be taken seriously. Nevertheless, it's clear from the SECOND statement that, in fact, it is recognized [by MacGregor] that the boat can be operated without the ballast under certain conditions." Jeff,- How many more times are you going to regurgitate the same illogical argument? Once more, the above statement was posted a year ago. - Why are you still ignoring it, other than the fact that you are desperately looking for a "gotcha". You obviously aren't willing to consider all my comments on the subject in context. Shame, Shame Shame!! And it does, though the mass aft largely comes from the 250 pound engine hanging off the transom. Not really. The mass aft largely comes from the crew/guests/skipper, not the motor (unless the boat is being sailed solo). The motor is slightly farther aft, but not much. (The captains seat is about a foot forward of the motor.) What a crock of ****. Do you actually read the stuff you write? Since the moment of inertia is proportional to the square of the distance from the center of mass, the mass of the engine is actually equivalent to a mass 4 time larger but half the distance to the center of mass. And you did take math, and geometry in high school? Consider a typical crew of two people (assume total weight of 350 lbs) and a skipper of 230 lbs. (about my weight). Assuming that the skipper is sitting on the captain's chair, about 1.5 ft forward of the center of the motor, and about 16 feet aft of the center of mass. Assuming that the two crew members are sitting two and three feet forward of the captain, respectively, their total mass will be the equivalent of 350 pounds positioned about 14.5 feet from the center of mass about which the boat has a tendency to pitch. The motor, at about 220 pounds is about 17.5 feet from the center of mass. Squaring the distances, the relative values of the rotational momentum of the skipper and crew are more than twice that of the motor, despite the fact that they are closer to the center of mass. Once again, Jeff, your theories are simply wrong. (If you wish, I'll provide the calculations and "foot pounds" or whatever, in greater detail.) In other words, the engine on the stern contributes roughly the same to the moment as crew that would equal the safe limit of the boat. Nope. Not if you do the math. You can't take a very light boat, and then claim that the heaviest feasible motor hung as far aft as possible only has negligible affect. Unless of course, you don't care if everyone thinks you're an idiot! Of course, I didn't say the motor has a negligible affect [sic]. As should now be understood, the volume and mass of the ballast is in an area slightly forward of amidships, rather near the mast. No - here you're wrong. The diagram clearly shows the largest cross-section by far at the first station, which is halfway between the mast and the bow. Nope. You're ignoring the permanent ballast and also the fact that the large section extends rearwardly aft of the mast. The first and second "station" are substantially the same. You're ****ting me, right? I mean you have looked at the diagram? http://www.macgregor26.com/drawings/drawings.htm Actually, the first, second, and third station are essentially the same. - The black area in the third section represents the permanent ballast, which is heavier than water. Or are you just assuming that someone out there hasn't looked and might believe you? The diagram pretty clearly shows a much larger cross section at the first station, perhaps almost double that of the second. Additionally, the (heavier) permanent ballast is positioned near the mast. We're not talking about the 300 pounds of permanent ballast. We're talking about the amount that is forward. You've got 1150 pounds to distribute. The diagram clearly shows the largest cross section of the tank at the first station, halfway to the bow. You're claiming there's very little aft. That would seem to imply 300 or so pounds in the far forward area. You can babble all you want, but it doesn't change that fact. http://www.macgregor26.com/drawings/drawings.htm Once again, Jeff, the ballast in the first, second, and third sectional views are essentially the same. With the exception that the permanent ballast has a higher density, and higher mass per unit of volume. Additionally, the ballast tank extends somewhat aft of the third section. The first section is actually somewhat smaller than the second, although through something of an optical illusion it appears as large. Moreover, the ballast tank is tapered at its forward and rear end portions, further reducing the mass of ballast spaced furthest from the central or largest portion, thereby lessening the moment of inertia of the ballast when the boat pitches upon a wave, etc. Nice words, but wrong. Anyone can clearly see that you're wrong, so why do you can insisting otherwise? Much of the mass of the tank is in the forward 20% of the boat. Because the tank is on the centerline, there is little tapering forward until you get very close to the bow. Wrong again, Jeff. You are apparently considering only the taper occurring across the width of the tank. - There is also a substantial taper in the vertical direction, when the tank is viewed from the side. As previously discussed, the ballast tank is (already) tapering upwardly at Section No. 1, and it continues to taper up sharply from that point forwardly, as can be seen most clearly in the longitudinal sectional view. I know it's a little hard for you to understand, Jeff, but give it another try. Look again, Jeff. The tank is tapered in both the vertical and horizontal directions or axes. The bottom of the tank curves upwardly sharply as it approaches the bow. The largest cross section is already way forward. Nope. You're clearly wrong. QED. End of story. The best that you can claim is that there isn't much in the last few inches. Last five or six feet. This is hundreds of pounds of ballast where a normally ballasted boat has no extra mass. Neither does the Mac. Actually, the tapering has little affect until the last few feet. In the Mac, the "last few feet" comprise a substantialy proportion of the distance from the mast to the bow. yada yada yada. We're talking distance from center of mass which is the center of flotation. If there is nothing submerged, that implies that the center of mass is further aft. You loose. Nope. The issue is whether the water AND permanent ballast extends substantially along the length of the boat (as you first thought) such that it contributes substantially to the momentum of the boat during pitching movement. - It doesn't, and the boat doesn't pitch excessively. Jeff, you again misquote what I said to make your point. - I never said that the "entire boat" was protected by a doubled hull. Only that adjacent the ballast tank. - Do you have any ethics at all? Once again, we have a case of you making a claim of and inner and outer hull and than after you were called on that you started backpedaling and trying to explain that its only the vulnerable part that is "protected." Once again, you come to your own interpretation of what I said, and you try to claim that that's what I must have meant. It isn't You quote from an ongoing discussion on this ng as if every time I post, they each of my notes should be scrutinized and foot-noted, as if I were drafting a legal brief to be sent to the Supreme Court. In the discussion to which you refer, I made the point that the Mac has what is in essence a double hull. - WHICH IS TRUE. Then, during the ongoing discussion, I explained that the ballast tank served to provide the same function as a double hull, in that if the outer hull below the tank was compromised, water would not be let into the hull. Jeff, don't you think that you ought to refer to my comments during the entire discussion, conducted months ago, rather than leap gleefully on one introductory comment of mine? From an ethical standpoint, wouldn't that be the thing to do? why? It doesn't change anything. You tried to claim: "the Macs have a number of advantages over most boats mentioned on this ng. They include a double liner in the hull such that if the lower hull is penetrated, water from the resulting opening normally does not enter the cabin, due to the fact that it is maintained within the ballast tank by the upper wall of the ballast tank." You were quite happy to leave the reader with the impression that this is a double hull, which has a very specific meaning in marine terminology. This is 6 months after I, and others, had already called you on this, so if this does not make you a blatant liar, I don't know what does. Actually, my statement was quite accurate. The ballast does provide protection if the lower hull is penetrated. It doesn't provide protection if the sides or chines of the boat are penetrated, and I never said that it did. In fact, now you're claiming that its only a small portion that is protected. Nope. It's rather a large portion. - (In fact, you claimed the ballast extended along the entire length of the boat.) Yes I did, and you corrected me on that. Your welcome. BTW, what the area is, it doesn't include the majority of the outside waterline, since the ballast runs down the center. Every case I've ever seen of a major hull breech has been on the side where there is no protection. In that case, you still wouldn't be out of luck on the Mac as you would be in your own boat, Jeff, since the flotation provided in the Mac would keep you afloat. In contrast, if you were on your own boat, the keel would quickly pull the boat to the bottom. There are two basic facts he First, the water ballast does not extend the full width, it is concentrated in the middle, so that any blow off the centerline is not protected. And while the bow area is protected, at high speed that is lifted out of the water and thus needs no protection. Actually, no. Although the bow will rise out of the water, most of the mid portions of the boat remain at or below the surface. If the bow is lifted out of the water, the Mac "double hull" can provide protection if the boat runs into or over a floating object. - My experience is that some of them are hard to see, even at slow speeds. If this is such a strong feature, why is it never mentioned in the Mac literature. Could it be that its a bogus safety feature? Actually, I didn't say it was "such a strong feature." I merely said that it was another advantageous feature on the Mac. Obviously, it isn't as effective as a conventional double hull, but again, most boats with double hulls don't include flotation. And now you're claiming there is little protection aft. Most impact would occur forward of amidships, Jeff. - Unless you were sailing backwards. This is clearly not true for a boat that is planing. Maybe, maybe not. - The Macs don't plane high out of the water like a high-speed power boat. - They are, after all, a sailboat. And the second point is that MacGregor itself never touts this as a feature - it one that you made made up! I didn't personally make it up. And I never said that the entire boat has a double hull. You were quite happy to word it in such a way as to leave that impression, while still maintaining denyability. Nope. That, again, was your own invention. And once more, you conveniently ignore my previous remarks discussing the limitations of the "double-hull" effect. Shame, shame shame, Jeff. You censor out anything you think might introduce a better understanding of my original discussion, and quote an excerpt from my original note ONLY, ignoring my subsequent discussion of the entire matter. Jeff, you apparently have no scruples whatsoever if you think you can pretend to have found a "gotcha." You tried to sell this one and got caught, so don't complain to me about "ethics." The ethics problems are your own, Jeff, not mine. - See below. Yes, we know you have no problem with ethics. You also again cherry picked the statement you relied on, since in later portions of that discussion some months ago I made it quite clear that the boat didn't have a doubled hull protecting the entire boat. - But you knew that when you decided to misrepresent and cherry pick my statement, didn't you Jeff? You shamelessly misquote and cherry-pick when you think you can get by with it. - Do you have no self-respect whatsoever, Jeff? Sorry Jim, this is another bell that you can't un-ring! When you made the comment originally you were quite happy to make it sound as if the boat had all the protection of a double hull. Nope. you're the one with a rung bell. See earlier discussion. You cherry-picked one introductory statement and ignored a numberof later ones. So? I ignored your comments after it was pointed out that you initial comments were bogus. Your backpedaling is not a fun target. However, 6 months later you came back again with our "double liner" comment. Because there is a double hull, over the lowermost, central portions of the hull. It was only after it was clear that the "protection" was very limited that you admitted that it doesn't have what is commonly referred to as a double hull. Here's the original note: ... As to safety (unless you plan on lending your boat to a drunk skipper who is going to carry 10 or more passengers, severely overloading the boat), the Macs have a number of advantages over most boats mentioned on this ng. They include a double liner in the hull such that if the lower hull is penetrated, water from the resulting opening normally does not enter the cabin, due to the fact that it is maintained within the ballast tank by the upper wall of the ballast tank. ... Jeff, that's hardly a statement that the entire boat is protected by a double hull. And you know it. First of all, that was 6 months after we had a lengthy discussion on the topic, so you're lying when you say that was the original note. Secondly, you obviously have no trouble wording that so that one might assume the "double liner" actually covers the hull, not a small portion of it. You could have easily said that there is "partial protection" but you preferred to use terminology easily confused with "double hull" which you know has a very specific meaning in the nautical world. Actually, I don't. - I don't have a captains license. But, once more, the lower portions of the hull are protected. I swear to you that I DID NOT intend to imply the the entire boat was protected. The context of the statement was that it was a part of a rather quick and dirty listing of some of the Mac features, rapidly written. (This is, after all, a newsgroup on which we can express opinions and views for mutual entertainment, as far as I knew. I didn't consider the fact that people like you would parse and cut apart and interpret the intended, hidden meaning of every statement I made.) But then, I can see how these little problems would not concern you. Since it's proportional to the square of the distance from the axis of pitching rotation, MacGregor's design (positioning most of the mass near amidships rather than evenly distributing it along the entire length of the boat) was proper. Excuse me???? What about that large mass called "the engine" which is about 10% of the dry weight and hanging of the stern??? The engine is closer to 5% of the weight of the boat with water ballast and crew. But that's only an error of about 50%, Jeff. - That's rather typical of your guestimates. Also, check out the math. - The momentum relating to the motor is less than half that of a typical skipper and crew, as explained above. And what about the huge amount of water ballast that get loaded near the bow of the boat??? Read my notes above on that subject, Jeff. Again, reality has no place in your logic, does it? In contrast with your cherry-picking, your censoring out or ignoring my statements dealing with these same issues with greater specificity, your twisting of my original meanings, and your devious "interpretations" of what I "must have intended" (never giving me the benefit of a doubt), you are the one who has a problem, Jeff, not me. After twisting my statements, censoring out anything you don't like, and reaching back to discussions posted more than a year ago, you end up concluding dogmatically that your own particular interpretation of what I actually was trying to say is the only acceptable interpretation. You are clearly the one with ethical problems, Jeff. Sad, difficult to understand or believe, but obviously true. Jim |
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![]() "JimC" wrote in message t... Jeff wrote: JimC wrote: snipped the remainder of an all-too-extensive exercise in self-flagellation I should like to proffer an impartial observation. I've slogged through this thread, examined the evidence and concluded the following: Jeff = Johnny Cochran; JimC = Marsha Clark. Paladin (Have gun - will travel) -- Posted via a free Usenet account from http://www.teranews.com |
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JimC wrote:
Jeff wrote: JimC wrote: Nope. It's actually quite relevant. The boat is built to be balanced, under sail or power, with the motor and a typical crew in the cockpit. By "balance" I meant that the hull, motor, ballast, and sails work togther to cause the boat to to sail and motor as efficiently as possible under a variety of applications. In general, it sails and powers well, it doesn't "pitch" excessively, and it is fun to sail. Nice backpedal. It clearly isn't what you meant the first few times around, but if you think it saves some face for you, so be it. Jeff, I have not wanted to get into the issue of weight distribution in detail, since you pretty well had your assed kicked all over the ng on that one. - How so? Only a total idiot could claim that a 250 pound engine hanging on the stern plus 300+ pounds of water up in the bow could have negligible affect on the pitch moment of a boat that only weighs 3600 pounds! Do you really think there's a single reader here that believes you??? Don't forget that you initially claimed that the ballast extends the full length of the boat, And it does. If you claim otherwise, you're a boldface liar. The most that you can claim is that the tank is rather small aft (its still much bigger than simply a drainage tube) but all this mean is that there's more weight up forward. You loose either way. and that was a bad distribution of mass (and would tend to increase pitching movement). So are you claiming that all naval architects are wrong when they try to minimize weight in the extremities? You can certainly claim the pitching isn't too bad (though few here would believe you) but you certainly can't claim that the mass distribution has no affect. After carefully explaining to you what the Mac drawings were showing, and responding to numerous notes, you were finally forced to back off your original claims, and admit that, well, there wasn't a lot of ballast in the aft portions of the boat. As I said only a liar would claim the tank doesn't extend the entire distance. I only admitted there wasn't much water ballast aft. You then claimed that the ballast extended all the way to the bow, so that was a problem also. - I then patiently though incorrectly explained that the ballast tank was pointed toward the bow and tapered BOTH VERTICALLY AND HORIZONTALLY as it approached the bow The tapering is clearly only in the last few inches. With the majority of the water ballast well forward of the mast, this is the equivalent of having a hundred gallon water tank under the vee of a slightly larger boat. Not a good thing. (as shown in the side sectional view and the cross-sections in the drawings you posted). I POSTED???? Those are on the MacGregor site!!! I posted no drawing, I merely posted a link to the factory site! My God, you really are a boldface liar! Not making much headway on either of these points, Find one reader of this that believes you. you then started to become hyper and jump up and down about the fact that the ballast tank was near the forward end of the bow, and the motor was at the stern. - As clearly shown in the factory diagram. I then explained that the center of mass of the ballast tank (tapered forwardly and rearwardly) was actually just slightly forward of amidships, Are you saying the diagram from the factory lies??? It clearly shows the largest cross-section to be halfway between the mast and the bow. and the motor, while positioned at the stern, actually comprises only a relatively small portion of the weight near the stern. Nonsense. Even a 5th grader can do the math that shows that the contribution to the moment of inertia of the engine is roughly equal to that of the crew. - The greatest weight factor being the skipper and crew But the moment is proportional to the distance SQUARED from the center of mass. So the moment of the engine will clearly be larger than that of the skipper and one or two crew, and possibly be equal to a full crew. Its math Jim, hard to argue with. and/or guests in the cockpit. Thus, although the motor is in the aft end of the boat, the crew/guests/skipper comprise a much greater mass factor at the aft end of the boat. Its the moment, not the mass. Jeff, I've gone over this with you and patiently though stupidly, because you seem to ignore the moment, and focus on the fact that the large mass hanging off the stern is balanced by the large mass towards the bow. explained it to you a number of times, yet you refuse to acknowledge that you just didn't get it. Get what? That you can't do simple sums? That you can read a simple drawing? I'm concluding that you thought you had a good "gotcha" to throw at me, but it turned out you didn't, and you just can't admit it to yourself or the ng. Sure thing. SHow me someone that believes you on that, Jim. or you just showing what type of lawyer you really are. Obviously the boat was designed to float on its lines with full ballast and an engine. The issue is whether a different distribution of mass would lead to a boat that sails better. Yet you HAVE NO SUGGESTIONS WHATSOEVER as to how to improve the distribution of mass. - If a bad distribution of mass is a key problem (actually, it isn't, since the boat sails and motors steadily and exhibits no excessive pitching movement) then, at a minimum, you should be able to tell us where you would move the outboard and/or the ballast. - But you don't want to get into that one, do you Jeff? I don't see your point. If you stay with a variety of the design parameters, such as light weigh on the trailer, a large engine, etc, it becomes hard to distribute the weight otherwise. It may even be that this is a reasonable solution, perhaps even the best, given the constraints. But for most sailers, the constraints that led to this design are not important, and the required compromises are not desirable. You're asking me to make one change that would reduce the pitch moment, and the answer is that's hard given that you want a 250 pound engine hanging off the stern. And just how would you redistribute the mass, Jeff? - Where would you move the outboard, and where would you move the ballast? I would not have designed this boat at all, so don't asked me have I might change it. All I wanted to do when I started this topic of discussion was to rationally consider how the different weight distribution affects stability and balance. But you wanted to turn this into something quite different. Nope. I responded to each of your points about weight distribution (see the above note), No - you denied the obvious truths. and then went on to further, related issues. The bottom line is that, if your theories were correct, the boat would pitch uncontrollably and bounce around in heavy weather. - But it doesn't. Why would you say that? Oh, I forgot, you're a lawyer. I never made any claim that it "pitches uncontrollably" but since you bring it up, maybe it does. The 26M is the result of years of development, feedback, and mods. It does a lot of things most sailboats can't do. If serves the needs of most sailors, under the conditions experienced 90% of the time. That's nonsense!!! Really? And you have sailed the 26m how many times?????? What is the significance of that? It's relatively inexpensive, debatable if you are willing to compare the costs of new boats to new boats, or used boats to used boats, and not compare the costs of 15 year old boats with that of a new Mac 26M similarly equipped. So why do they seem to depreciate twice as fast as other boats? Where are your stats on that one, Jeff???? Just look at the asking prices. We've been through this before. As one of the few on this ng willing to defend the Macs, I'll continue to do my part to ensure that Mac discussions have at least a semblance of balance and accuracy. If I'm right, I'll try provide a good, but balanced and fair defense of the Mac. That's a laugh. even when you know you're wrong, and then you say "it doesn't matter that I'm lying because I'm having fun." You may disagree with my conclusions, Jeff, but tell me where I have lied to you or anyone else? Its hard to find a place where you told the truth. You keep saying "show me where I lied" but you ignore it when I do. (Paying attention to what I actually said in several notes, for a change, and ignoring for a moment WHAT YOU INTERPRETED as the meaning of portions of some of my comments.) Jeff, which are the top ten most egregious lies I have posted on the ng? Or, failing that, the top five? --- Two, maybe? I did that in my last post. So that's one lie right there. Jeff, we may have differing opinions, and you seem to have confused your own opinions as facts, but would you please name the more egregious instances of my lying? Perhaps you could list the top ten instances? Being a clever lawyer, you word things so that they will be taken one way, but you can claim you said something different. Your comment above about balance was one such example. See comments above. The bottom line is that you simply misunderstood the Mac drawings. Are you denying that the largest cross-section of the ballast tank is at station one, well forward of the mast? Are you? The "double liner" discussion is another. See prior comments. - I NEVER said that the ballast tank protected the entire boat. - That was another of your own, rather convenient "gotcha" interpretations. By going into detail on the "double liner" you implied such protection. Especially after you were informed the the term "double hull" specifically implies such complete protection. You're being disingenuous here, Jim. Your claim that the outboard is much lighter than a diesel is another. I'm claiming that the outboard is lighter than a diesel with sufficient power for the Mac when all the associated components, including the drive shaft and supporting structures are included. Also, I seriously doubt that a small (e.g., 10-15 hp motor would be sufficient to drive the Mac through heavy chop and adverse winds. That's not what you claimed originally Jim, and you you know it. That's another lie! You specifically claimed that the diesel in similar sized boats was much heavier than the outboard on a Mac. Now you claiming that because of the poor design of the hull it needs the huge engine that no other 26 footer requires. Your claim that the ballast is very close to the center is yet another. It is. - Your problem is that you didn't understand the drawings. Again - are you claiming that the cross-section of the tank is not substantially large at station one than at any other? Are you trying to say blue is red over and over and hoping someone will buy it? They question is, Jim, when have you been completely truthful? Although I don't claim omniscience, I have certainly endeavored to be truthful and to present a balanced response and evaluation of the Mac. For example, I have noted a number of limitations inherent with the boat. - I have acknowledged that it normally doesn't sail as fast or point as high as most conventional boats with weighted keels. I have acknowledged that it isn't suitable for extended blue water crossings, etc. I have acknowledged that it is lightly built. - - - Why haven't you complemented me for being upfront concerning THESE issues, Jeff? They do seem to be self evident. You make lots of claims, and then try to write them off by saying, "but its fun to sail." What's your point? Because that's the key factor, from my perspective. Then why don't you just leave it at that? Remember, I've said a number of times that it a reasonable boat for certainly situations - I've haven't been claiming its inherently evil. Actually, all I've done is try try to keep you honest on some of the more outlandish claims. However, I don't think I agree that a typical diesel, with generator, fuel pump, filters, prop shaft, etc., would weigh about the same as a modern outboard. - Any stats on that one? I thought I just gave one. The weight of a 15 Hp Yanmar, including everything (alternator, pumps, filter) except the shaft and prop is 249 lbs. Clearly one might add another fuel filter or water filter, and the muffler weighs a few pounds (mine are plastic) but all of this is only a few pounds, and then your outboard also has a few extra bits and pieces not included in its base weight. Also, since the diesel generates almost twice the power from a pound of fuel, one can claim a huge weight advantage on that front. You're omitting some items, such as the drive shaft, shaft bushing assembly, I certainly didn't ignore the shaft, I mentioned right up there. Another lie. supporting framework in the boat, Are you seriously claiming there is no "supporting framework" on the Mac. I already pointed that out to you, so that's yet another lie on your part. How can you really claim you never lie? etc. You're also comparing a 15 hp motor with a 50 hp motor, and you're not addressing the fact that the Mac requires lots of power to keep in on course in heavy weather, chop, winds, etc. Why does the Mac "require" it, when no other 26 foot sailboat does? Wouldn't that seem like a design flaw? That's more than my 50 hp weighs. Also, add the weight of the drive shaft, the drive shaft bushings, the mounting hardware, the reinforcements to the hull supporting the motor, etc. Yes, we know that the mac has no reinforcements to the hull supporting its motor. You really are intent on showing how lawyers lie, aren't you? It has enough. You made the claim that a diesel is much heavier than an outboard, and that simply isn't true. Further, the issue has nothing to do with the possible difference of 20 pounds, it has to do with the distribution. Re weight distribution, see my comments above. - I can understand why you would be embarrassed about that one and prefer that we not discuss it again. So are your really claiming that weight distribution has no affect? As to the relative weight, it seems that you want us to accept your personal opinions about how much the typical diesel engine for a small sailboat weighs from your I was quoting from the Yanmar specs, using the most frequently spec'd diesel for small sailboats. Originally I mentioned to two cylinder version, because you had asked what someone had in their boat. But for one as light as the Mac, a one cylinder could do. Having powered the Mac 26M in somewhat heavy weather, I don't think a small engine will do the job Jeff. It's a large, light weight boat with high freeboard and no weighted keel, and it needs lots of power to keep it one course. That would seem to be a flaw. My boat has no weighted keel and high freeboard, and a couple of small engines handle it very nicely. In fact the original design (and most of my sisterships) only have twin 9.9 HP outboards. More lies! I mentioned that the weight for a diesel doesn't include several items, including the drive shaft. It does include most of the others you've mentioned - fuel filter, cooling system, pumps, alternators etc. Some of what you claim are needed for your installation. Are you trying to claim there is no mounting hardware or reinforcement, no controls, no fuel tanks? How about the fact that the gas engine needs twice the fuel? First, although the transom is sufficiently strong to support the motor, Only because its reinforced, you jackass! I don't see any additional support structures for the motor. Yah right. Give me a friggin break, Jimbo. The "mounting hardware" consists of some bolts, washers, and the like. Secondly, there are controls, consisting largely of a tubular connecting bar and cables extending to the steering mechanism. - Again, nothing that would add any substantial mass, unless you consider the small steering wheel to be "massive." The fuel tank is a 10-gal. plastic tank. - Again, only a few pounds of "mass." Next, regarding the cost of all that fuel, we get around 3 - 5 miles per gallon at plaining speeds, and I have probably spent about $25 on gas during the past six months. Of course, as an attorney, I have lots of money to spend on all that gas, so it really isn't a major factor. (That's a joke, Jeff. Of course.) It isn't the cost, you bozo! Its the range! You say you get 30 miles from that tank. A small diesel pushing a normal sailboat your size would be 3-4 time more efficient. If you wanted to go any distance you'd need a second tank while the diesel wouldn't. That's about 70 pounds of fuel. Actually, I spend most of the time sailing, not motoring. Also, because of work assignments last Summer and Fall I was limited in how much I was able to take the boat out. Still, gas costs haven't been a major factor. again, its range, not cost. Hey, you're the one who brought this up. You claimed your engine was much lighter than the diesel on most similarly sized sailboats. I pointed out you're wrong. Jeff, in reviewing my note and your responses, I now think I was wrong in saying the weight of my 50 hp outboard was "much lighter" than a typical diesel on most sailboats in the 27 - 29 ft range. I think it is somewhat lighter when all factors are considered, and it's more powerful, but my statement as written was apparently incorrect. - I had come to a (mistaken) judgment from working with larger diesels on larger boats. Still, my statement about the safety factors entailed in having a fairly powerful motor on the Mac is accurate, IMO. - For example, when I had the boat out last, as mentioned earlier, we had a rather substantial incoming tide and headwind, the waves were breaking against us all the way out to the sailing area, and there was a lot of traffic, with wakes. The Mac is lightweight and has a fairly large sideboard area. - If I had had a 10 - 15 hp motor as is often the case for boats of this size, I don't think I could have kept it on track within the channel all the way out. I don't get it. Why does the Mac "need" an engine 3 times as powerful as all of its competition. And why is that a safety feature? |
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"Jeff" wrote in message
. .. I don't get it. Why does the Mac "need" an engine 3 times as powerful as all of its competition. And why is that a safety feature? Because the "sailor" driving it is either insecure about himself or not experienced enough to deal with the conditions, including "getting to the sailing area" under sail. The engine should be a last resort. -- "j" ganz @@ www.sailnow.com |
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JimC wrote:
And you did take math, and geometry in high school? Consider a typical crew of two people (assume total weight of 350 lbs) and a skipper of 230 lbs. (about my weight). Assuming that the skipper is sitting on the captain's chair, about 1.5 ft forward of the center of the motor, and about 16 feet aft of the center of mass. Assuming that the two crew members are sitting two and three feet forward of the captain, respectively, their total mass will be the equivalent of 350 pounds positioned about 14.5 feet from the center of mass about which the boat has a tendency to pitch. The motor, at about 220 pounds is about 17.5 feet from the center of mass. Squaring the distances, the relative values of the rotational momentum of the skipper and crew are more than twice that of the motor, despite the fact that they are closer to the center of mass. Once again, Jeff, your theories are simply wrong. (If you wish, I'll provide the calculations and "foot pounds" or whatever, in greater detail.) Jim: I thought I'd run your numbers through my calculator, just for fun: (14.5ft)^2*350lbs=7.36E4ft^2-lbs , that's 73,600 for the exponent challenged. (17.5ft)^2*220lbs=6.74E4ft^2-lbs , 67,400 .... Maybe you think that 73,600 is more than TWICE 67,400, but I beg to differ. To a physicist, they're essentially the same thing. Point to Jeff. Cheers Marty ------------ And now a word from our sponsor ------------------ For a quality usenet news server, try DNEWS, easy to install, fast, efficient and reliable. For home servers or carrier class installations with millions of users it will allow you to grow! ---- See http://netwinsite.com/sponsor/sponsor_dnews.htm ---- |
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Paladin wrote:
"JimC" wrote in message t... Jeff wrote: JimC wrote: snipped the remainder of an all-too-extensive exercise in self-flagellation I should like to proffer an impartial observation. I've slogged through this thread, examined the evidence and concluded the following: Jeff = Johnny Cochran; JimC = Marsha Clark. If the glove fits? Or in this case doesn't. Cheers Marty |
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Martin Baxter wrote:
JimC wrote: And you did take math, and geometry in high school? Consider a typical crew of two people (assume total weight of 350 lbs) and a skipper of 230 lbs. (about my weight). Assuming that the skipper is sitting on the captain's chair, about 1.5 ft forward of the center of the motor, and about 16 feet aft of the center of mass. Assuming that the two crew members are sitting two and three feet forward of the captain, respectively, their total mass will be the equivalent of 350 pounds positioned about 14.5 feet from the center of mass about which the boat has a tendency to pitch. The motor, at about 220 pounds is about 17.5 feet from the center of mass. Squaring the distances, the relative values of the rotational momentum of the skipper and crew are more than twice that of the motor, despite the fact that they are closer to the center of mass. Once again, Jeff, your theories are simply wrong. (If you wish, I'll provide the calculations and "foot pounds" or whatever, in greater detail.) Jim: I thought I'd run your numbers through my calculator, just for fun: (14.5ft)^2*350lbs=7.36E4ft^2-lbs , that's 73,600 for the exponent challenged. (17.5ft)^2*220lbs=6.74E4ft^2-lbs , 67,400 .... Maybe you think that 73,600 is more than TWICE 67,400, but I beg to differ. To a physicist, they're essentially the same thing. Point to Jeff. Gawd, I don't believe other people are still reading this! Thanks for doing the math, but the are a few problems here. Jim uses his weight (230 lbs) when clearly this should be done with a "standard" weight (160 lbs). Secondly, Jim invents the figure of 16 feet forward of the helm seat for the center of mass, which puts it only 8.5 feet aft of the bow! Clearly, it has to be more like 11-12 feet forward of the stern. This has a huge affect on the r^2 part of the formula, especially for the crew forward of the helm. |
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