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#1
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"JAXAshby" wrote in message
... jeffies, a boat under sail has one hell of a lot more drag than a boat motoring in a flat calm. And how is this relevant to anything? also, keep in mind that the boat under discussion is a Westsail 32, a boat usually having a minimum of 30 hp installed, and often 40+ hp. A Westsail 32 with a 10 to 12 hp engine installed is unmarketable. One would need one hell of a lot patience to wait for wind and tide before setting off. Are you claiming that an aux engine is always run at an rpm that produces its full rated power? Most boaters understand that a diesel might only produce half its rated output at cruise speed. For example, a Yanmar 3YM is rated at 29 HP only delivers about 14 to the prop at 2800 rpm. Although the OP has a Westsail, he asked what other boaters have experienced, so the discussion is about all boats. As I said elsewhere, I think the Westsail would benefit less than other boats from a low drag prop. keep in mind that props don't drag all that much anyway. according to the MIT data, even a fixed 3 blade only pulled 170# on a boat at 5 knots, or about the equivelent of 2-1/2 hp. That's not much drag??? That's roughly the drag from a 25 knot breeze! Are you saying that this would have no affect on boat speed? Are you claiming that a having a 2.5 hp engine pulling backwards would have little affect on speed? At the low RPMs many boats use to go 5 knots, they only use 10 to 12 hp to go forward |
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#3
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Time for the meds again, jaxie. Your reading comprehension is failing. I made
no claim of the Westsail, I said "At the low RPMs many boats use to go 5 knots, they only use 10 to 12 hp to go forward." Are you claiming that a Westsail is representative of "many boats"? If fact, I already said several times that I didn't think a low drag prop would help a Westsail that much, but they could be of value to many other boats. You've been claiming that they are useless for any boat other than a high performance racer. Since you lost that argument, you're now backpedaling and misrepresenting my comments. Typical lying from cowardly jaxie. But, since you brought it up, how much power does a Westsail actually use? At 5 knots, that is a "Speed to Length" ratio of 0.95 (where the 7 knot hull speed would be 1.34). To achieve that speed, a displacement boat will have 1400 pounds per HP. At 20,000 pounds, the Westsail uses about 14.2 HP. A bit higher than the "10 to 12" I mentioned for "many boats," but most 32 footers don't weigh anywhere near 10 tons. How much wind is needed to generate 14 hp on a Westsail? With 650 square feet of sail, assuming 0.02 HP/sq.ft. at 14 knots wind, this is 13 HP; so it looks like about 15 to 16 knots of wind is needed to get a Westsail up to 5 knots. "JAXAshby" wrote in message ... jeffies, **you** claimed it only takes 10 or 12 hp to push a Westsail 32 at five knots. remember? nah, I am sure you don't remember anything from more than 7 hours ago. From: "Jeff Morris" Date: 9/4/2004 11:11 PM Eastern Daylight Time Message-id: "JAXAshby" wrote in message ... jeffies, a boat under sail has one hell of a lot more drag than a boat motoring in a flat calm. And how is this relevant to anything? also, keep in mind that the boat under discussion is a Westsail 32, a boat usually having a minimum of 30 hp installed, and often 40+ hp. A Westsail 32 with a 10 to 12 hp engine installed is unmarketable. One would need one hell of a lot patience to wait for wind and tide before setting off. Are you claiming that an aux engine is always run at an rpm that produces its full rated power? Most boaters understand that a diesel might only produce half its rated output at cruise speed. For example, a Yanmar 3YM is rated at 29 HP only delivers about 14 to the prop at 2800 rpm. Although the OP has a Westsail, he asked what other boaters have experienced, so the discussion is about all boats. As I said elsewhere, I think the Westsail would benefit less than other boats from a low drag prop. keep in mind that props don't drag all that much anyway. according to the MIT data, even a fixed 3 blade only pulled 170# on a boat at 5 knots, or about the equivelent of 2-1/2 hp. That's not much drag??? That's roughly the drag from a 25 knot breeze! Are you saying that this would have no affect on boat speed? Are you claiming that a having a 2.5 hp engine pulling backwards would have little affect on speed? At the low RPMs many boats use to go 5 knots, they only use 10 to 12 hp to go forward |
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#4
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jeffies, the discussion has from the start been about a Westsail 32. ask your
wife to reread the posts for you. From: "Jeff Morris" Date: 9/5/2004 10:55 AM Eastern Daylight Time Message-id: Time for the meds again, jaxie. Your reading comprehension is failing. I made no claim of the Westsail, I said "At the low RPMs many boats use to go 5 knots, they only use 10 to 12 hp to go forward." Are you claiming that a Westsail is representative of "many boats"? If fact, I already said several times that I didn't think a low drag prop would help a Westsail that much, but they could be of value to many other boats. You've been claiming that they are useless for any boat other than a high performance racer. Since you lost that argument, you're now backpedaling and misrepresenting my comments. Typical lying from cowardly jaxie. But, since you brought it up, how much power does a Westsail actually use? At 5 knots, that is a "Speed to Length" ratio of 0.95 (where the 7 knot hull speed would be 1.34). To achieve that speed, a displacement boat will have 1400 pounds per HP. At 20,000 pounds, the Westsail uses about 14.2 HP. A bit higher than the "10 to 12" I mentioned for "many boats," but most 32 footers don't weigh anywhere near 10 tons. How much wind is needed to generate 14 hp on a Westsail? With 650 square feet of sail, assuming 0.02 HP/sq.ft. at 14 knots wind, this is 13 HP; so it looks like about 15 to 16 knots of wind is needed to get a Westsail up to 5 knots. "JAXAshby" wrote in message ... jeffies, **you** claimed it only takes 10 or 12 hp to push a Westsail 32 at five knots. remember? nah, I am sure you don't remember anything from more than 7 hours ago. From: "Jeff Morris" Date: 9/4/2004 11:11 PM Eastern Daylight Time Message-id: "JAXAshby" wrote in message ... jeffies, a boat under sail has one hell of a lot more drag than a boat motoring in a flat calm. And how is this relevant to anything? also, keep in mind that the boat under discussion is a Westsail 32, a boat usually having a minimum of 30 hp installed, and often 40+ hp. A Westsail 32 with a 10 to 12 hp engine installed is unmarketable. One would need one hell of a lot patience to wait for wind and tide before setting off. Are you claiming that an aux engine is always run at an rpm that produces its full rated power? Most boaters understand that a diesel might only produce half its rated output at cruise speed. For example, a Yanmar 3YM is rated at 29 HP only delivers about 14 to the prop at 2800 rpm. Although the OP has a Westsail, he asked what other boaters have experienced, so the discussion is about all boats. As I said elsewhere, I think the Westsail would benefit less than other boats from a low drag prop. keep in mind that props don't drag all that much anyway. according to the MIT data, even a fixed 3 blade only pulled 170# on a boat at 5 knots, or about the equivelent of 2-1/2 hp. That's not much drag??? That's roughly the drag from a 25 knot breeze! Are you saying that this would have no affect on boat speed? Are you claiming that a having a 2.5 hp engine pulling backwards would have little affect on speed? At the low RPMs many boats use to go 5 knots, they only use 10 to 12 hp to go forward |
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#5
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jaxie, even my cat understands that you changed the thread by claiming the
folders "only have value for racing boats." Now that you've been proven wrong on that, you're backpedaling as fast as you can. Don't hurt yourself. "JAXAshby" wrote in message ... jeffies, the discussion has from the start been about a Westsail 32. ask your wife to reread the posts for you. From: "Jeff Morris" Date: 9/5/2004 10:55 AM Eastern Daylight Time Message-id: Time for the meds again, jaxie. Your reading comprehension is failing. I made no claim of the Westsail, I said "At the low RPMs many boats use to go 5 knots, they only use 10 to 12 hp to go forward." Are you claiming that a Westsail is representative of "many boats"? If fact, I already said several times that I didn't think a low drag prop would help a Westsail that much, but they could be of value to many other boats. You've been claiming that they are useless for any boat other than a high performance racer. Since you lost that argument, you're now backpedaling and misrepresenting my comments. Typical lying from cowardly jaxie. But, since you brought it up, how much power does a Westsail actually use? At 5 knots, that is a "Speed to Length" ratio of 0.95 (where the 7 knot hull speed would be 1.34). To achieve that speed, a displacement boat will have 1400 pounds per HP. At 20,000 pounds, the Westsail uses about 14.2 HP. A bit higher than the "10 to 12" I mentioned for "many boats," but most 32 footers don't weigh anywhere near 10 tons. How much wind is needed to generate 14 hp on a Westsail? With 650 square feet of sail, assuming 0.02 HP/sq.ft. at 14 knots wind, this is 13 HP; so it looks like about 15 to 16 knots of wind is needed to get a Westsail up to 5 knots. "JAXAshby" wrote in message ... jeffies, **you** claimed it only takes 10 or 12 hp to push a Westsail 32 at five knots. remember? nah, I am sure you don't remember anything from more than 7 hours ago. From: "Jeff Morris" Date: 9/4/2004 11:11 PM Eastern Daylight Time Message-id: "JAXAshby" wrote in message ... jeffies, a boat under sail has one hell of a lot more drag than a boat motoring in a flat calm. And how is this relevant to anything? also, keep in mind that the boat under discussion is a Westsail 32, a boat usually having a minimum of 30 hp installed, and often 40+ hp. A Westsail 32 with a 10 to 12 hp engine installed is unmarketable. One would need one hell of a lot patience to wait for wind and tide before setting off. Are you claiming that an aux engine is always run at an rpm that produces its full rated power? Most boaters understand that a diesel might only produce half its rated output at cruise speed. For example, a Yanmar 3YM is rated at 29 HP only delivers about 14 to the prop at 2800 rpm. Although the OP has a Westsail, he asked what other boaters have experienced, so the discussion is about all boats. As I said elsewhere, I think the Westsail would benefit less than other boats from a low drag prop. keep in mind that props don't drag all that much anyway. according to the MIT data, even a fixed 3 blade only pulled 170# on a boat at 5 knots, or about the equivelent of 2-1/2 hp. That's not much drag??? That's roughly the drag from a 25 knot breeze! Are you saying that this would have no affect on boat speed? Are you claiming that a having a 2.5 hp engine pulling backwards would have little affect on speed? At the low RPMs many boats use to go 5 knots, they only use 10 to 12 hp to go forward |
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#6
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jeffies, attempting rational discussion with you is attempting rational
discussion with the village idiot. you just smile and chew on flower picked from the hedge. btw, jeffies, what everyone else is fully aware of and you are totally ignorant of is that folding/feathering prop manufacturers promote their products' value at ---- low ---- wind speeds, not high speeds. duh. From: "Jeff Morris" Date: 9/5/2004 3:09 PM Eastern Daylight Time Message-id: jaxie, even my cat understands that you changed the thread by claiming the folders "only have value for racing boats." Now that you've been proven wrong on that, you're backpedaling as fast as you can. Don't hurt yourself. "JAXAshby" wrote in message ... jeffies, the discussion has from the start been about a Westsail 32. ask your wife to reread the posts for you. From: "Jeff Morris" Date: 9/5/2004 10:55 AM Eastern Daylight Time Message-id: Time for the meds again, jaxie. Your reading comprehension is failing. I made no claim of the Westsail, I said "At the low RPMs many boats use to go 5 knots, they only use 10 to 12 hp to go forward." Are you claiming that a Westsail is representative of "many boats"? If fact, I already said several times that I didn't think a low drag prop would help a Westsail that much, but they could be of value to many other boats. You've been claiming that they are useless for any boat other than a high performance racer. Since you lost that argument, you're now backpedaling and misrepresenting my comments. Typical lying from cowardly jaxie. But, since you brought it up, how much power does a Westsail actually use? At 5 knots, that is a "Speed to Length" ratio of 0.95 (where the 7 knot hull speed would be 1.34). To achieve that speed, a displacement boat will have 1400 pounds per HP. At 20,000 pounds, the Westsail uses about 14.2 HP. A bit higher than the "10 to 12" I mentioned for "many boats," but most 32 footers don't weigh anywhere near 10 tons. How much wind is needed to generate 14 hp on a Westsail? With 650 square feet of sail, assuming 0.02 HP/sq.ft. at 14 knots wind, this is 13 HP; so it looks like about 15 to 16 knots of wind is needed to get a Westsail up to 5 knots. "JAXAshby" wrote in message ... jeffies, **you** claimed it only takes 10 or 12 hp to push a Westsail 32 at five knots. remember? nah, I am sure you don't remember anything from more than 7 hours ago. From: "Jeff Morris" Date: 9/4/2004 11:11 PM Eastern Daylight Time Message-id: "JAXAshby" wrote in message ... jeffies, a boat under sail has one hell of a lot more drag than a boat motoring in a flat calm. And how is this relevant to anything? also, keep in mind that the boat under discussion is a Westsail 32, a boat usually having a minimum of 30 hp installed, and often 40+ hp. A Westsail 32 with a 10 to 12 hp engine installed is unmarketable. One would need one hell of a lot patience to wait for wind and tide before setting off. Are you claiming that an aux engine is always run at an rpm that produces its full rated power? Most boaters understand that a diesel might only produce half its rated output at cruise speed. For example, a Yanmar 3YM is rated at 29 HP only delivers about 14 to the prop at 2800 rpm. Although the OP has a Westsail, he asked what other boaters have experienced, so the discussion is about all boats. As I said elsewhere, I think the Westsail would benefit less than other boats from a low drag prop. keep in mind that props don't drag all that much anyway. according to the MIT data, even a fixed 3 blade only pulled 170# on a boat at 5 knots, or about the equivelent of 2-1/2 hp. That's not much drag??? That's roughly the drag from a 25 knot breeze! Are you saying that this would have no affect on boat speed? Are you claiming that a having a 2.5 hp engine pulling backwards would have little affect on speed? At the low RPMs many boats use to go 5 knots, they only use 10 to 12 hp to go forward |
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#7
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Some salesman might have tried to sell you on low speed performance because he
knew you were scared of high performance boats, but the drag of fixed props at low speeds is not that great. Its only really significant at higher speeds. As everyone else knows, appendage drag goes up with the square of speed. Perhaps you can show us even one folding/feathering manufacturer's site that claims the primary advantage is a low speed. "JAXAshby" wrote in message ... btw, jeffies, what everyone else is fully aware of and you are totally ignorant of is that folding/feathering prop manufacturers promote their products' value at ---- low ---- wind speeds, not high speeds. duh. From: "Jeff Morris" Date: 9/5/2004 3:09 PM Eastern Daylight Time Message-id: jaxie, even my cat understands that you changed the thread by claiming the folders "only have value for racing boats." Now that you've been proven wrong on that, you're backpedaling as fast as you can. Don't hurt yourself. "JAXAshby" wrote in message ... jeffies, the discussion has from the start been about a Westsail 32. ask your wife to reread the posts for you. From: "Jeff Morris" Date: 9/5/2004 10:55 AM Eastern Daylight Time Message-id: Time for the meds again, jaxie. Your reading comprehension is failing. I made no claim of the Westsail, I said "At the low RPMs many boats use to go 5 knots, they only use 10 to 12 hp to go forward." Are you claiming that a Westsail is representative of "many boats"? If fact, I already said several times that I didn't think a low drag prop would help a Westsail that much, but they could be of value to many other boats. You've been claiming that they are useless for any boat other than a high performance racer. Since you lost that argument, you're now backpedaling and misrepresenting my comments. Typical lying from cowardly jaxie. But, since you brought it up, how much power does a Westsail actually use? At 5 knots, that is a "Speed to Length" ratio of 0.95 (where the 7 knot hull speed would be 1.34). To achieve that speed, a displacement boat will have 1400 pounds per HP. At 20,000 pounds, the Westsail uses about 14.2 HP. A bit higher than the "10 to 12" I mentioned for "many boats," but most 32 footers don't weigh anywhere near 10 tons. How much wind is needed to generate 14 hp on a Westsail? With 650 square feet of sail, assuming 0.02 HP/sq.ft. at 14 knots wind, this is 13 HP; so it looks like about 15 to 16 knots of wind is needed to get a Westsail up to 5 knots. "JAXAshby" wrote in message ... jeffies, **you** claimed it only takes 10 or 12 hp to push a Westsail 32 at five knots. remember? nah, I am sure you don't remember anything from more than 7 hours ago. From: "Jeff Morris" Date: 9/4/2004 11:11 PM Eastern Daylight Time Message-id: "JAXAshby" wrote in message ... jeffies, a boat under sail has one hell of a lot more drag than a boat motoring in a flat calm. And how is this relevant to anything? also, keep in mind that the boat under discussion is a Westsail 32, a boat usually having a minimum of 30 hp installed, and often 40+ hp. A Westsail 32 with a 10 to 12 hp engine installed is unmarketable. One would need one hell of a lot patience to wait for wind and tide before setting off. Are you claiming that an aux engine is always run at an rpm that produces its full rated power? Most boaters understand that a diesel might only produce half its rated output at cruise speed. For example, a Yanmar 3YM is rated at 29 HP only delivers about 14 to the prop at 2800 rpm. Although the OP has a Westsail, he asked what other boaters have experienced, so the discussion is about all boats. As I said elsewhere, I think the Westsail would benefit less than other boats from a low drag prop. keep in mind that props don't drag all that much anyway. according to the MIT data, even a fixed 3 blade only pulled 170# on a boat at 5 knots, or about the equivelent of 2-1/2 hp. That's not much drag??? That's roughly the drag from a 25 knot breeze! Are you saying that this would have no affect on boat speed? Are you claiming that a having a 2.5 hp engine pulling backwards would have little affect on speed? At the low RPMs many boats use to go 5 knots, they only use 10 to 12 hp to go forward |
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#8
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jeffies, if folding/feathering/kinda twisting props increased performance by
your claimed 10% ALL new boats would have them installed at the factory. duh. From: "Jeff Morris" Date: 9/5/2004 10:55 AM Eastern Daylight Time Message-id: Time for the meds again, jaxie. Your reading comprehension is failing. I made no claim of the Westsail, I said "At the low RPMs many boats use to go 5 knots, they only use 10 to 12 hp to go forward." Are you claiming that a Westsail is representative of "many boats"? If fact, I already said several times that I didn't think a low drag prop would help a Westsail that much, but they could be of value to many other boats. You've been claiming that they are useless for any boat other than a high performance racer. Since you lost that argument, you're now backpedaling and misrepresenting my comments. Typical lying from cowardly jaxie. But, since you brought it up, how much power does a Westsail actually use? At 5 knots, that is a "Speed to Length" ratio of 0.95 (where the 7 knot hull speed would be 1.34). To achieve that speed, a displacement boat will have 1400 pounds per HP. At 20,000 pounds, the Westsail uses about 14.2 HP. A bit higher than the "10 to 12" I mentioned for "many boats," but most 32 footers don't weigh anywhere near 10 tons. How much wind is needed to generate 14 hp on a Westsail? With 650 square feet of sail, assuming 0.02 HP/sq.ft. at 14 knots wind, this is 13 HP; so it looks like about 15 to 16 knots of wind is needed to get a Westsail up to 5 knots. "JAXAshby" wrote in message ... jeffies, **you** claimed it only takes 10 or 12 hp to push a Westsail 32 at five knots. remember? nah, I am sure you don't remember anything from more than 7 hours ago. From: "Jeff Morris" Date: 9/4/2004 11:11 PM Eastern Daylight Time Message-id: "JAXAshby" wrote in message ... jeffies, a boat under sail has one hell of a lot more drag than a boat motoring in a flat calm. And how is this relevant to anything? also, keep in mind that the boat under discussion is a Westsail 32, a boat usually having a minimum of 30 hp installed, and often 40+ hp. A Westsail 32 with a 10 to 12 hp engine installed is unmarketable. One would need one hell of a lot patience to wait for wind and tide before setting off. Are you claiming that an aux engine is always run at an rpm that produces its full rated power? Most boaters understand that a diesel might only produce half its rated output at cruise speed. For example, a Yanmar 3YM is rated at 29 HP only delivers about 14 to the prop at 2800 rpm. Although the OP has a Westsail, he asked what other boaters have experienced, so the discussion is about all boats. As I said elsewhere, I think the Westsail would benefit less than other boats from a low drag prop. keep in mind that props don't drag all that much anyway. according to the MIT data, even a fixed 3 blade only pulled 170# on a boat at 5 knots, or about the equivelent of 2-1/2 hp. That's not much drag??? That's roughly the drag from a 25 knot breeze! Are you saying that this would have no affect on boat speed? Are you claiming that a having a 2.5 hp engine pulling backwards would have little affect on speed? At the low RPMs many boats use to go 5 knots, they only use 10 to 12 hp to go forward |
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#9
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Many boats do. Mine came with folders. Many (most?) of the JBoats come with
folders or feathering props. But this was 10% over a 3-blade at high speed; the drag for a 2-blade at moderate speed is somewhat less. And there are downsides to folders and feathering props, such as reverse thrust, cost, reliability. They are not for everyone, but they are certainly a reasonable option for many cruisers. "JAXAshby" wrote in message ... jeffies, if folding/feathering/kinda twisting props increased performance by your claimed 10% ALL new boats would have them installed at the factory. duh. From: "Jeff Morris" Date: 9/5/2004 10:55 AM Eastern Daylight Time Message-id: Time for the meds again, jaxie. Your reading comprehension is failing. I made no claim of the Westsail, I said "At the low RPMs many boats use to go 5 knots, they only use 10 to 12 hp to go forward." Are you claiming that a Westsail is representative of "many boats"? If fact, I already said several times that I didn't think a low drag prop would help a Westsail that much, but they could be of value to many other boats. You've been claiming that they are useless for any boat other than a high performance racer. Since you lost that argument, you're now backpedaling and misrepresenting my comments. Typical lying from cowardly jaxie. But, since you brought it up, how much power does a Westsail actually use? At 5 knots, that is a "Speed to Length" ratio of 0.95 (where the 7 knot hull speed would be 1.34). To achieve that speed, a displacement boat will have 1400 pounds per HP. At 20,000 pounds, the Westsail uses about 14.2 HP. A bit higher than the "10 to 12" I mentioned for "many boats," but most 32 footers don't weigh anywhere near 10 tons. How much wind is needed to generate 14 hp on a Westsail? With 650 square feet of sail, assuming 0.02 HP/sq.ft. at 14 knots wind, this is 13 HP; so it looks like about 15 to 16 knots of wind is needed to get a Westsail up to 5 knots. "JAXAshby" wrote in message ... jeffies, **you** claimed it only takes 10 or 12 hp to push a Westsail 32 at five knots. remember? nah, I am sure you don't remember anything from more than 7 hours ago. From: "Jeff Morris" Date: 9/4/2004 11:11 PM Eastern Daylight Time Message-id: "JAXAshby" wrote in message ... jeffies, a boat under sail has one hell of a lot more drag than a boat motoring in a flat calm. And how is this relevant to anything? also, keep in mind that the boat under discussion is a Westsail 32, a boat usually having a minimum of 30 hp installed, and often 40+ hp. A Westsail 32 with a 10 to 12 hp engine installed is unmarketable. One would need one hell of a lot patience to wait for wind and tide before setting off. Are you claiming that an aux engine is always run at an rpm that produces its full rated power? Most boaters understand that a diesel might only produce half its rated output at cruise speed. For example, a Yanmar 3YM is rated at 29 HP only delivers about 14 to the prop at 2800 rpm. Although the OP has a Westsail, he asked what other boaters have experienced, so the discussion is about all boats. As I said elsewhere, I think the Westsail would benefit less than other boats from a low drag prop. keep in mind that props don't drag all that much anyway. according to the MIT data, even a fixed 3 blade only pulled 170# on a boat at 5 knots, or about the equivelent of 2-1/2 hp. That's not much drag??? That's roughly the drag from a 25 knot breeze! Are you saying that this would have no affect on boat speed? Are you claiming that a having a 2.5 hp engine pulling backwards would have little affect on speed? At the low RPMs many boats use to go 5 knots, they only use 10 to 12 hp to go forward |
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