LeeJerry

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About LeeJerry

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  1. Is that a trick question? He cashes the checks from the advertisers.
  2. Keith Musto was probably the only “legend” I’ve had the privilege to sail with, many moons ago. (He drove in a major Melges 24 event and we were in the Corinthian division – he was a tailor, so Cat 1.) I had the opportunity to chat with and ask Russell Coutts, in town for a symposium, to sail frostbite series with us the following day. He declined, claiming he had to catch a flight. We debated whether, if he had accepted, would I have had to have let him drive? I’ve had the chance to chat with Gary Jobson a couple times, but never sail with him. I’ve also sailed with several pros, but they were at best only legends in their own minds (at least one for sure).
  3. I did, thanks! FB- Doug Not until next Wednesday (6 days), for the first WNR of the year. Of course, although warm, the weather around here will not be very conducive to sailing at least through Saturday according the current conditions and the forecast.
  4. Well, was the diagram I posted not visible to you? I said "Weight on the rail has max righting moment when level, weight in the bulb is does nothing until the boat is heeled (max at 90 which is slow)." The weight (ie the effect of gravity on mass) of a ballast bulb (assumed to be on the centerline, as the vast majority are) DOES NOT generate -any- righting moment when the vessel is level. Is that what got your panties in a wad? If so, then buzz off back to kiddygarten. As I have stated, I agree that the bulb “DOES NOT generate -any- righting moment when the vessel is level,” so no panty issues there. But that is not what you said; maybe it is what you meant or maybe not, I don’t know. What you actually said was that it “does nothing (until the …)”. The first part of your sentence referred to righting moment, but you did not follow it with ‘weight in the bulb does not generate any’ or ‘does nothing for righting moment’ or any similar statement. You said “weight in the bulb is does nothing until…” And this statement is wrong, again as I’ve previously explained (it lowers the CG). However, what happens at zero heel is only of SECONDARY concern. My issue is not the exact angle at which maximum (total) righting moment occurs. It is the contribution of the bulb and your claim that it (the bulb’s contribution) is maximum at (or near) 90 deg and therefore something less at other angles. I didn’t necessarily mean to call you out on it, but had seen similar thoughts enough in these pages and apparently felt it was time to correct it. I have stated and explained why the bulb contributes the same at all angles. You have yet to even acknowledge that you understand that this is my PRIMARY issue, let alone try to address it. Here is another opportunity. If you meant the righting moment of the whole boat was max near 90 deg, then say so (it's not what you wrote). Otherwise, what does the bulb do differently at 90 deg than what it does at 10 deg? The CG of the fixed keel boat does not move within the hull (or ‘relative to’ if you want to consider multihulls), even as the boat is oriented differently ‘in space.’ This is different than the entire hull moving relative to the water. Contrast this to shifting ballast transversally (crew, canting keel), which does move the CG relative to the hull. I’ll recognize this as simply a matter of different nomenclature, which is not really of interest to me, at most a tertiary issue. I was the one to first suggest (twice) looking at metacentric height. I know what it is. GM, the metacentric height, is the distance from the center of gravity (G) to the metacenter (M). For those not familiar with this term, as heel approaches zero the buoyant force will tend to cross the centerline at the same point (i.e. approach one point) and this point is called the metacenter. For an initially stable boat, M will be above G. Thus, moving weight from the hull and putting it in a keel/bulb (say, as shown in the upper left figure of post #40) will lower the CG (say, from point #1 to point #3) and therefore increase the GM. This is NOT “doing nothing.”
  5. Umm, yes but why should I? Everybody who CAN understand it already does without further explanation from me. I was out yesterday... I don’t know about should*, but I would think that you ought to support the statement you made (you haven’t yet), because I don’t think you can. I think that you won’t (under the guise of ‘why should I’), because I don’t think that you can. * But then again, this is the interweb, where you can anonymously say anything you want (done), not back it up (done) and simply call people names (and done). I expect Trump is your hero. All I can do is point out the mistake (done), explain why it is wrong (done) and ignore your insults (and done).
  6. I paused as to whether I wanted to reply. What you say is correct (even if not necessarily the issue), especially the last line. Cheers, Lee
  7. LJ, this should be self-explanatory stability_dgrm_1_7ballast.gif The cylindrical hull section contributes nothing to RM in terms of shifting bouyancy, it's all about the Vertical Center of Gravity. Of course not all hulls are cylindrical, if you examine the -opposite- case (an extreme scow or a catamaran) the shift in CB is much greater than the shift in CG along the horizontal axis; however then you consider that the ballast is a component of displacement then the RM at a given angle of heel would be much less without it because of the reduced displacement. (and this is why such boats generally don't use conventionall placed ballast, it does them little good until they are heeled beyond normal sailing angles) Here's another little cartoon I had laying around, explains Vertical Center of Gravity a little: stability_dgrm_1_6_wt.gif stability_dgrm_1_7_wt.jpg Now LJ I hope this cleared things up a little for you. I apologize to everyone else for the distraction FB- Doug So your answer to “how the bulb contributes…” is to not show a bulb, nor a CG nor a CB? But seriously, that figure (the first figure, not the latter two; don’t much see how they help you) was a reasonable example of the CG moving rather than the CB (even if it doesn’t much represent reality). But the CG is still fixed relative to the hull, and it still doesn't address the statement you made. Let me try, for one last time (hopefully, probably) to explain why I say you are wrong. With reference to the upper left “boat” of the figure in post #40: It shows a “hull CG” in the middle of the section; call this point 1. It also shows a “keel CG” below the section; call this point 2. When these two weights are combined, the resulting system “CG” shown below point 1 and above point 2 is created; call this point 3. This latter position of the CG, point 3, is used to determine the stability of the boat, including the righting arm and moment. The “contribution” of the keel (bulb) is to shift the CG from point 1 to point 3, and this shift is the same regardless of the angle of heel (including zero heel). QED Can you provide a similar, concise statement that supports your claim? Now you may try superposition to break down the individual contributions of each component in doing the stability calcs, but it in the end it still simplifies to the above.
  8. No ad hominem, stating the truth. It's clear that you are struggling with some basic concepts and it's not really my place to teach you (especially if you're unwilling). What makes you think I am unwilling? I don't really see the point of arguing the contribution of something to something else that doesn't exist (is zero). It is just as right (or wrong) to say it contributes everything as to say it contributes nothing of something that doesn't exist. But that's too philosophical. As I said before, look at initial stability (rather than righting moment). Let me try rewording as a question: how does the GM (metacentric height) of a boat without the keel compare to that of the boat with the keel? You can use the rectangular boat that ______ presented in post #40. It seems to me that you don't think there is a difference, since GM doesn't require any heel. I never said that. What I said was the contribution was the same regardless of the heel angle. If you are not moving the ballast around, then yes it is distance between the fixed CG and the moving CB (accounting for the appropriate angles) that creates the righting arm. Now, ignore all of the above (at least for the moment). Consider it rhetorical. Please explain, per your statement, how the bulb contributes the max at 90 deg, and further how it differs from the contribution at other angles, say 60, 30 or 10 deg.
  9. Not sure how to respond, considering everything other than your first three words are basically correct and agree with (or at least don’t contradict) what I said. Starting with your second sentence: “This only happens when there is a horizontal difference between COG and COB.” This is correct and is exactly what I said: “It is the center of buoyancy that shifts with heel creating the righting moment.“ The keel / bulb (of a fixed keel) does nothing to move the CG from where it was as the boat heels, so the bulb is not contributing anything different to the righting moment as heel changes, even at 90 deg. Your first sentence is a little less straight forward: “…since the COB and COG are lined up vertically at zero heel the bulb does nothing in terms of righting moment.” So while this is basically correct (with implied assumptions of symmetry, etc.), it isn’t a particularly useful statement either. This gets a little esoteric (or maybe existential), but if the CB and CG are aligned vertically, then there is no righting moment and therefore nothing for the bulb to contribute to. However, if we change your sentence slightly to replace the phrase “righting moment” with “stability” then the statement becomes “…since the COB and COG are lined up vertically at zero heel the bulb does nothing in terms of stability,” and this statement would be false. You may want to look into “stiffness,” “initial stability” or “metacentric height” to see what I mean. The conclusion is that the initial statement “…weight in the bulb is (sic) does nothing until the boat is heeled (max at 90 which is slow)” is wrong, as I previously said. It is a common misconception. If the “zero heel” is really giving you heartburn, then I suggest replacing it with “0.00001 deg of heel” and see if that helps. Oh, and if you want to get into the semantics, the first part of the original statement is also wrong: “Weight on the rail has max righting moment when level,…” As a boat heels (to leeward), the CB will shift to leeward at a rate initially greater than the transverse, horizontal distance of the weight on the rail decreases, resulting in an increase in the righting moment. The max will occur at some value of heel (to leeward) greater than zero, but dependent on a number of factors so can't generalize a value. Oh my god. Can you get any more pedantic? If required, probably yes. I do this for a living. And I would say that Doug succinctly captured the truth. No, what Doug said was unequivocally wrong (The portion I highlighted, at least. Sorry Doug.). If you did this for a living, I'd (I would) expect you to know that. It is a common mistake that I was trying to make slightly less common. Lee Jerry you are a pedant today. Perhaps, and often other days, too. Way over the top. You're (you are) entitled to your opinion. And while you are correct that weight on the rail is not max at level for the reasons you state, I think the point was clear enough. OK. You get more for your money on the rail and it works better when you aren't heeled a lot. You get less for your money with a keel--you have to heel (and go slow and slide sideways) before it really does much for you--all else equal (total weight, hull etc). No, you just get different for your money. It may be "more" or it may be "less" depending on what your goals are. I'd (I would) go into more detail, but don't (do not) want to be too pedantic. See comments embedded above in blue. Wow. Difficult to be both pedantic and ignorant at the same time, but you pull it off magnificently. I suggest sailing more and worrying less about the exactly precise way of defining stuff that's too difficult for you. FB- Doug Nice ad hominem attack on the messenger while completely ignoring the message. But then again, that is the SA way, especially when you can’t defend your own statement with reason. Sorry if your feelings or ego got hurt, however the statement was wrong. If you’d like to challenge or discuss that latter idea, then fine, otherwise whatever…
  10. Not true. The weight of a fixed keel (including bulb) is contributing exactly the same at zero heel as it does at any other angle. It is the center of buoyancy that shifts with heel creating the righting moment. You can also shift weight transversely to move the center of gravity, but this is independent of heel and doesn't happen with a fixed keel. Actually fully true - since the COB and COG are lined up vertically at zero heel the bulb does nothing in terms of righting moment. This only happens when there is a horizontal difference between COG and COB Not sure how to respond, considering everything other than your first three words are basically correct and agree with (or at least don’t contradict) what I said. Starting with your second sentence: “This only happens when there is a horizontal difference between COG and COB.” This is correct and is exactly what I said: “It is the center of buoyancy that shifts with heel creating the righting moment.“ The keel / bulb (of a fixed keel) does nothing to move the CG from where it was as the boat heels, so the bulb is not contributing anything different to the righting moment as heel changes, even at 90 deg. Your first sentence is a little less straight forward: “…since the COB and COG are lined up vertically at zero heel the bulb does nothing in terms of righting moment.” So while this is basically correct (with implied assumptions of symmetry, etc.), it isn’t a particularly useful statement either. This gets a little esoteric (or maybe existential), but if the CB and CG are aligned vertically, then there is no righting moment and therefore nothing for the bulb to contribute to. However, if we change your sentence slightly to replace the phrase “righting moment” with “stability” then the statement becomes “…since the COB and COG are lined up vertically at zero heel the bulb does nothing in terms of stability,” and this statement would be false. You may want to look into “stiffness,” “initial stability” or “metacentric height” to see what I mean. The conclusion is that the initial statement “…weight in the bulb is (sic) does nothing until the boat is heeled (max at 90 which is slow)” is wrong, as I previously said. It is a common misconception. If the “zero heel” is really giving you heartburn, then I suggest replacing it with “0.00001 deg of heel” and see if that helps. Oh, and if you want to get into the semantics, the first part of the original statement is also wrong: “Weight on the rail has max righting moment when level,…” As a boat heels (to leeward), the CB will shift to leeward at a rate initially greater than the transverse, horizontal distance of the weight on the rail decreases, resulting in an increase in the righting moment. The max will occur at some value of heel (to leeward) greater than zero, but dependent on a number of factors so can't generalize a value. Oh my god. Can you get any more pedantic? If required, probably yes. I do this for a living. And I would say that Doug succinctly captured the truth. No, what Doug said was unequivocally wrong (The portion I highlighted, at least. Sorry Doug.). If you did this for a living, I'd (I would) expect you to know that. It is a common mistake that I was trying to make slightly less common. Lee Jerry you are a pedant today. Perhaps, and often other days, too. Way over the top. You're (you are) entitled to your opinion. And while you are correct that weight on the rail is not max at level for the reasons you state, I think the point was clear enough. OK. You get more for your money on the rail and it works better when you aren't heeled a lot. You get less for your money with a keel--you have to heel (and go slow and slide sideways) before it really does much for you--all else equal (total weight, hull etc). No, you just get different for your money. It may be "more" or it may be "less" depending on what your goals are. I'd (I would) go into more detail, but don't (do not) want to be too pedantic. See comments embedded above in blue.
  11. Hmm, I'm not so hopeful about the physics & math abilities of local PHRF committees. Weight on the rail does not convert to weight in a bulb. Weight on the rail has max righting moment when level, weight in the bulb is does nothing until the boat is heeled (max at 90 which is slow). FB- Doug Not true. The weight of a fixed keel (including bulb) is contributing exactly the same at zero heel as it does at any other angle. It is the center of buoyancy that shifts with heel creating the righting moment. You can also shift weight transversely to move the center of gravity, but this is independent of heel and doesn't happen with a fixed keel. Actually fully true - since the COB and COG are lined up vertically at zero heel the bulb does nothing in terms of righting moment. This only happens when there is a horizontal difference between COG and COB Not sure how to respond, considering everything other than your first three words are basically correct and agree with (or at least don’t contradict) what I said. Starting with your second sentence: “This only happens when there is a horizontal difference between COG and COB.” This is correct and is exactly what I said: “It is the center of buoyancy that shifts with heel creating the righting moment.“ The keel / bulb (of a fixed keel) does nothing to move the CG from where it was as the boat heels, so the bulb is not contributing anything different to the righting moment as heel changes, even at 90 deg. Your first sentence is a little less straight forward: “…since the COB and COG are lined up vertically at zero heel the bulb does nothing in terms of righting moment.” So while this is basically correct (with implied assumptions of symmetry, etc.), it isn’t a particularly useful statement either. This gets a little esoteric (or maybe existential), but if the CB and CG are aligned vertically, then there is no righting moment and therefore nothing for the bulb to contribute to. However, if we change your sentence slightly to replace the phrase “righting moment” with “stability” then the statement becomes “…since the COB and COG are lined up vertically at zero heel the bulb does nothing in terms of stability,” and this statement would be false. You may want to look into “stiffness,” “initial stability” or “metacentric height” to see what I mean. The conclusion is that the initial statement “…weight in the bulb is (sic) does nothing until the boat is heeled (max at 90 which is slow)” is wrong, as I previously said. It is a common misconception. If the “zero heel” is really giving you heartburn, then I suggest replacing it with “0.00001 deg of heel” and see if that helps. Oh, and if you want to get into the semantics, the first part of the original statement is also wrong: “Weight on the rail has max righting moment when level,…” As a boat heels (to leeward), the CB will shift to leeward at a rate initially greater than the transverse, horizontal distance of the weight on the rail decreases, resulting in an increase in the righting moment. The max will occur at some value of heel (to leeward) greater than zero, but dependent on a number of factors so can't generalize a value.
  12. Hmm, I'm not so hopeful about the physics & math abilities of local PHRF committees. Weight on the rail does not convert to weight in a bulb. Weight on the rail has max righting moment when level, weight in the bulb is does nothing until the boat is heeled (max at 90 which is slow). FB- Doug Not true. The weight of a fixed keel (including bulb) is contributing exactly the same at zero heel as it does at any other angle. It is the center of buoyancy that shifts with heel creating the righting moment. You can also shift weight transversely to move the center of gravity, but this is independent of heel and doesn't happen with a fixed keel.
  13. Yes. Chicago-Mac race, early 2000s, I believe it was member JOD in the thick of it (on the receiving end).
  14. That is too late to do a "recall." The proper procedure would be to "abandon" (and return to starting area), November flag. The result is the same, just different flags are flown. Personally, I have no problem with a race being abandoned if it is deemed to be unfair to all by the RC (but not simply to help out his buddy who is in last place), especially if it will be restarted immediately. I do wonder why it took so long in this case though.
  15. What's the big deal? Doesn't look that radical. The shape doesn't look that new or original. Looks like an overgrown Catalina 37 from the late 80s (or early 90s?). Or more recently, it reminds me of a Wally (even if most of them aren't completely flush deck). There are others that are similar too. Wood construction certainly not new. So he did add some artsy touches to the wheel, binnacle, port lights...