Home |
Search |
Today's Posts |
#122
|
|||
|
|||
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 |
#123
|
|||
|
|||
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 |
#124
|
|||
|
|||
oh poor jaxie, the jealousy is just dripping off him now!
"JAXAshby" wrote in message ... I've had little problem in reverse. But then, I have two diesels jeffies, your props don't give a rat's what fuel your engines burn. In fact, your props are totally unable to determine what fuel your engines use. so, pray tell, why do **you** think your props can tell the difference. |
#125
|
|||
|
|||
oh poor jaxie, the jealousy is just dripping off him now!
what jealousy is that, jeffies? "JAXAshby" wrote in message ... I've had little problem in reverse. But then, I have two diesels jeffies, your props don't give a rat's what fuel your engines burn. In fact, your props are totally unable to determine what fuel your engines use. so, pray tell, why do **you** think your props can tell the difference. |
#126
|
|||
|
|||
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 |
#127
|
|||
|
|||
the drag of fixed props at
low speeds is not that great. yup. but that is the market feathering props aim at. at the high end, just a teeny bit more sail pushes the boat faster than you wanna go anyway. From: "Jeff Morris" Date: 9/5/2004 9:55 PM Eastern Daylight Time Message-id: 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 |
#128
|
|||
|
|||
Its a little hard to add sail area when you're already at full sail. One major
advantage of lightweight boats is that they can be driven to high speeds with a relatively small rig. For example, we showed that a Westsail might go 5 knots with 650 sq. feet of sail in 16 knots of wind. My boat, weighing half that of a Westsail, will go 8 knots in that wind, with only 540 feet of sail. If I had 3-blade fixed props I'd probably only be doing 7 or even less. The bottom line is that the folders give me extra speed (or save un-necessary loss) in any moderate wind condition. "JAXAshby" wrote in message ... the drag of fixed props at low speeds is not that great. yup. but that is the market feathering props aim at. at the high end, just a teeny bit more sail pushes the boat faster than you wanna go anyway. From: "Jeff Morris" Date: 9/5/2004 9:55 PM Eastern Daylight Time Message-id: 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 |
#129
|
|||
|
|||
The bottom line
is that the folders give me extra speed (or save un-necessary loss) in any moderate wind condition. keep telling yourself that, jeffies, and pretty soon you will convince yourself of its "truth". the prop manufacturers don't say that, but you go ahead and repeat a silly mantra as to how much you "invested". geesh, don't let science get in your way. |
#130
|
|||
|
|||
So are you claiming that the MIT study that said that a 3-blade prop could slow
a boat up to 0.8 knots was bad science? Since I have two props, and frequently sail at 7 to 9 knots, wouldn't these results be especially important to me? Sorry jaxie, the science is on my side. "JAXAshby" wrote in message ... The bottom line is that the folders give me extra speed (or save un-necessary loss) in any moderate wind condition. keep telling yourself that, jeffies, and pretty soon you will convince yourself of its "truth". the prop manufacturers don't say that, but you go ahead and repeat a silly mantra as to how much you "invested". geesh, don't let science get in your way. |
Reply |
Thread Tools | Search this Thread |
Display Modes | |
|
|
Similar Threads | ||||
Thread | Forum | |||
Rigid vang...pros & cons? | General |