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On Mon, 7 Jun 2021 09:13:31 -0700 (PDT), Tom Kunich
wrote: On Saturday, June 5, 2021 at 10:34:18 PM UTC-7, pH wrote: On 2021-06-01, Joerg wrote: snip The game changer, of course, is the Li ion technology since if was so easy for uninformed users to kill off their lead acid battery pack. Li-Ion also has its issues. For example, even top brand manufacturers do not seem to understand that it is not a good idea to top off a Li-Ion battery at close to 100% charge and then leave the bike in the garage that way. This results in premature aging and loss of capacity. The smarter way is to offer 80% or so which is plenty for a short ride into town. Then let users top it off in the morning when they expect to go on a very long ride. In the same way, don't ride it all the way down to where the low-batt cutoff turns it off, at least not often. "Smart" battery chargers would seem to be in order. Push the button if you need more than an 80% charge this time for some reason. NiMH would be more robust, but that chemistry never seemed to catch on before Lithium came on the scene. NiMH doesn't have an adequate energy density. A NiHM-battery that can last 40-50mi would be unreasonably large and heavy. [...] pH in Aptos Is the old stranded concrete ship still there? Use..the SS Palo Alto. About two years ago the winter storms broke the last 1/4 of the stern off and it twisted about 80 degrees from level. When I was a tad one could actually walk out to the bow. Then it was fenced off at half way. Then when I came back from college and other things it was closed off entirely and you can only walk out to the end of the pier the ship abutts. Sigh. Things change. Concrete exposed to water saturation degrades surprisingly rapidly. One of the instruments I was working on detected leaks from degrading concrete is swimming pools. I would imagine that you could make a pool thick enough to delay this for a long time as those concrete barges showed. But degrade they will. The concrete turns back to almost a mush consistency. Oh, you mean like the Alvord Lake Bridge that was built in 1889 in San Francisco, CA. This bridge was the first reinforced concrete bridge, and it still exists today, over one hundred years after it was built! Or maybe the Hoover Dam? Constructed some 85 years ago and still standing. Up to this time, the largest scale concrete project ever completed. -- Cheers, John B. |
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On 6/7/2021 5:25 PM, John B. wrote:
On Mon, 7 Jun 2021 09:13:31 -0700 (PDT), Tom Kunich wrote: On Saturday, June 5, 2021 at 10:34:18 PM UTC-7, pH wrote: On 2021-06-01, Joerg wrote: snip The game changer, of course, is the Li ion technology since if was so easy for uninformed users to kill off their lead acid battery pack. Li-Ion also has its issues. For example, even top brand manufacturers do not seem to understand that it is not a good idea to top off a Li-Ion battery at close to 100% charge and then leave the bike in the garage that way. This results in premature aging and loss of capacity. The smarter way is to offer 80% or so which is plenty for a short ride into town. Then let users top it off in the morning when they expect to go on a very long ride. In the same way, don't ride it all the way down to where the low-batt cutoff turns it off, at least not often. "Smart" battery chargers would seem to be in order. Push the button if you need more than an 80% charge this time for some reason. NiMH would be more robust, but that chemistry never seemed to catch on before Lithium came on the scene. NiMH doesn't have an adequate energy density. A NiHM-battery that can last 40-50mi would be unreasonably large and heavy. [...] pH in Aptos Is the old stranded concrete ship still there? Use..the SS Palo Alto. About two years ago the winter storms broke the last 1/4 of the stern off and it twisted about 80 degrees from level. When I was a tad one could actually walk out to the bow. Then it was fenced off at half way. Then when I came back from college and other things it was closed off entirely and you can only walk out to the end of the pier the ship abutts. Sigh. Things change. Concrete exposed to water saturation degrades surprisingly rapidly. One of the instruments I was working on detected leaks from degrading concrete is swimming pools. I would imagine that you could make a pool thick enough to delay this for a long time as those concrete barges showed. But degrade they will. The concrete turns back to almost a mush consistency. Oh, you mean like the Alvord Lake Bridge that was built in 1889 in San Francisco, CA. This bridge was the first reinforced concrete bridge, and it still exists today, over one hundred years after it was built! Or maybe the Hoover Dam? Constructed some 85 years ago and still standing. Up to this time, the largest scale concrete project ever completed. +1 Concrete can be durable if it's done right: https://www.historicmysteries.com/roman-concrete/ Couple thousand years anyway, maybe longer. -- Andrew Muzi www.yellowjersey.org/ Open every day since 1 April, 1971 |
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On Monday, June 7, 2021 at 3:25:30 PM UTC-7, John B. wrote:
On Mon, 7 Jun 2021 09:13:31 -0700 (PDT), Tom Kunich wrote: On Saturday, June 5, 2021 at 10:34:18 PM UTC-7, pH wrote: On 2021-06-01, Joerg wrote: snip The game changer, of course, is the Li ion technology since if was so easy for uninformed users to kill off their lead acid battery pack. Li-Ion also has its issues. For example, even top brand manufacturers do not seem to understand that it is not a good idea to top off a Li-Ion battery at close to 100% charge and then leave the bike in the garage that way. This results in premature aging and loss of capacity. The smarter way is to offer 80% or so which is plenty for a short ride into town. Then let users top it off in the morning when they expect to go on a very long ride. In the same way, don't ride it all the way down to where the low-batt cutoff turns it off, at least not often. "Smart" battery chargers would seem to be in order. Push the button if you need more than an 80% charge this time for some reason. NiMH would be more robust, but that chemistry never seemed to catch on before Lithium came on the scene. NiMH doesn't have an adequate energy density. A NiHM-battery that can last 40-50mi would be unreasonably large and heavy. [...] pH in Aptos Is the old stranded concrete ship still there? Use..the SS Palo Alto. About two years ago the winter storms broke the last 1/4 of the stern off and it twisted about 80 degrees from level. When I was a tad one could actually walk out to the bow. Then it was fenced off at half way. Then when I came back from college and other things it was closed off entirely and you can only walk out to the end of the pier the ship abutts. Sigh. Things change. Concrete exposed to water saturation degrades surprisingly rapidly. One of the instruments I was working on detected leaks from degrading concrete is swimming pools. I would imagine that you could make a pool thick enough to delay this for a long time as those concrete barges showed. But degrade they will. The concrete turns back to almost a mush consistency. Oh, you mean like the Alvord Lake Bridge that was built in 1889 in San Francisco, CA. This bridge was the first reinforced concrete bridge, and it still exists today, over one hundred years after it was built! Or maybe the Hoover Dam? Constructed some 85 years ago and still standing. Up to this time, the largest scale concrete project ever completed. So explain to everyone here what water the Alvord Lake Bridge is on? Since cars pass beneath it it would be a real trick for there to be a waterway beneath it. As for Hoover Dam, why do you insist on showing your ignorance on every subject under the sun? The fam is 45 ft thick at the surface and rarely has water up to that level. The bottom of the dam is 660 feet thick. Perhaps you'd care to explain to us how that compared to a concrete barge with a wall thickness of 18"? Because you can use Google doesn't mean you know a damn thing you anti-intellectual. |
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On Mon, 07 Jun 2021 17:44:13 -0500, AMuzi wrote:
Concrete can be durable if it's done right: https://www.historicmysteries.com/roman-concrete/ Couple thousand years anyway, maybe longer. Yep. However, hydraulic cement isn't the current problem. The Romans didn't have rebar. The problem is that concrete is 15 to 20% water. You can convince yourself that there's water in concrete with a oxy-acetylene torch and watch concrete chunks fly from the steam explosions. When rebar rusts, it expands, which causes the concrete to crack. Once it cracks, more water, chlorides, acidic liquids, etc get in and cause some more rust. If the Romans had rebar, they would have had the same problems we're having: "Concrete degradation" https://en.wikipedia.org/wiki/Concrete_degradation -- Jeff Liebermann PO Box 272 http://www.LearnByDestroying.com Ben Lomond CA 95005-0272 Skype: JeffLiebermann AE6KS 831-336-2558 |
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On Mon, 7 Jun 2021 16:06:05 -0700 (PDT), Tom Kunich
wrote: On Monday, June 7, 2021 at 3:25:30 PM UTC-7, John B. wrote: On Mon, 7 Jun 2021 09:13:31 -0700 (PDT), Tom Kunich wrote: On Saturday, June 5, 2021 at 10:34:18 PM UTC-7, pH wrote: On 2021-06-01, Joerg wrote: snip The game changer, of course, is the Li ion technology since if was so easy for uninformed users to kill off their lead acid battery pack. Li-Ion also has its issues. For example, even top brand manufacturers do not seem to understand that it is not a good idea to top off a Li-Ion battery at close to 100% charge and then leave the bike in the garage that way. This results in premature aging and loss of capacity. The smarter way is to offer 80% or so which is plenty for a short ride into town. Then let users top it off in the morning when they expect to go on a very long ride. In the same way, don't ride it all the way down to where the low-batt cutoff turns it off, at least not often. "Smart" battery chargers would seem to be in order. Push the button if you need more than an 80% charge this time for some reason. NiMH would be more robust, but that chemistry never seemed to catch on before Lithium came on the scene. NiMH doesn't have an adequate energy density. A NiHM-battery that can last 40-50mi would be unreasonably large and heavy. [...] pH in Aptos Is the old stranded concrete ship still there? Use..the SS Palo Alto. About two years ago the winter storms broke the last 1/4 of the stern off and it twisted about 80 degrees from level. When I was a tad one could actually walk out to the bow. Then it was fenced off at half way. Then when I came back from college and other things it was closed off entirely and you can only walk out to the end of the pier the ship abutts. Sigh. Things change. Concrete exposed to water saturation degrades surprisingly rapidly. One of the instruments I was working on detected leaks from degrading concrete is swimming pools. I would imagine that you could make a pool thick enough to delay this for a long time as those concrete barges showed. But degrade they will. The concrete turns back to almost a mush consistency. Oh, you mean like the Alvord Lake Bridge that was built in 1889 in San Francisco, CA. This bridge was the first reinforced concrete bridge, and it still exists today, over one hundred years after it was built! Or maybe the Hoover Dam? Constructed some 85 years ago and still standing. Up to this time, the largest scale concrete project ever completed. So explain to everyone here what water the Alvord Lake Bridge is on? Since cars pass beneath it it would be a real trick for there to be a waterway beneath it. As for Hoover Dam, why do you insist on showing your ignorance on every subject under the sun? The fam is 45 ft thick at the surface and rarely has water up to that level. The bottom of the dam is 660 feet thick. Perhaps you'd care to explain to us how that compared to a concrete barge with a wall thickness of 18"? Because you can use Google doesn't mean you know a damn thing you anti-intellectual. You wrote, "Concrete exposed to water saturation degrades". But perhaps the Hoover Dam doesn't contain water? As for the Alvord Lake Bridge have a look at https://www.foundsf.org/index.php?ti... p15.1138.jpg See the cars going under the bridge? -- Cheers, John B. |
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On Mon, 7 Jun 2021 16:06:05 -0700 (PDT), Tom Kunich
wrote: On Monday, June 7, 2021 at 3:25:30 PM UTC-7, John B. wrote: On Mon, 7 Jun 2021 09:13:31 -0700 (PDT), Tom Kunich wrote: On Saturday, June 5, 2021 at 10:34:18 PM UTC-7, pH wrote: On 2021-06-01, Joerg wrote: snip The game changer, of course, is the Li ion technology since if was so easy for uninformed users to kill off their lead acid battery pack. Li-Ion also has its issues. For example, even top brand manufacturers do not seem to understand that it is not a good idea to top off a Li-Ion battery at close to 100% charge and then leave the bike in the garage that way. This results in premature aging and loss of capacity. The smarter way is to offer 80% or so which is plenty for a short ride into town. Then let users top it off in the morning when they expect to go on a very long ride. In the same way, don't ride it all the way down to where the low-batt cutoff turns it off, at least not often. "Smart" battery chargers would seem to be in order. Push the button if you need more than an 80% charge this time for some reason. NiMH would be more robust, but that chemistry never seemed to catch on before Lithium came on the scene. NiMH doesn't have an adequate energy density. A NiHM-battery that can last 40-50mi would be unreasonably large and heavy. [...] pH in Aptos Is the old stranded concrete ship still there? Use..the SS Palo Alto. About two years ago the winter storms broke the last 1/4 of the stern off and it twisted about 80 degrees from level. When I was a tad one could actually walk out to the bow. Then it was fenced off at half way. Then when I came back from college and other things it was closed off entirely and you can only walk out to the end of the pier the ship abutts. Sigh. Things change. Concrete exposed to water saturation degrades surprisingly rapidly. One of the instruments I was working on detected leaks from degrading concrete is swimming pools. I would imagine that you could make a pool thick enough to delay this for a long time as those concrete barges showed. But degrade they will. The concrete turns back to almost a mush consistency. Oh, you mean like the Alvord Lake Bridge that was built in 1889 in San Francisco, CA. This bridge was the first reinforced concrete bridge, and it still exists today, over one hundred years after it was built! Or maybe the Hoover Dam? Constructed some 85 years ago and still standing. Up to this time, the largest scale concrete project ever completed. So explain to everyone here what water the Alvord Lake Bridge is on? Mostly true. The bridge originally had water under it: https://www.foundsf.org/index.php?title=File:Alvord_Lake_and_Bridge,_at_Ha ight_Street_entrance_to_Golden_Gate_Park_c_1890_wn p15.1138.jpg https://sfrichmondreview.com/2018/03/03/swan-on-the-lake/ Since cars pass beneath it it would be a real trick for there to be a waterway beneath it. At some point in the past, the lake was filled with dirt to ground level. I couldn't find an exact date. The earliest photo showing a road instead of a lake was dated 1913, so I assume that there was water under the bridge for no more than 24 years. This is what the bridge looks like recently: https://historicbridges.org/bridges/browser/photosviewer.php?bridgebrowser=california/alvordlake/&gallerynum=1&gallerysize=1 https://www.atlasobscura.com/places/alvord-lake-bridge No water, so this bridge is not a good example of concrete longevity. Looks like they did some rebar and masonry repair work in 2020 for damage caused by roots and ground movement: http://giampolinicourtney.com/alvord-lake-bridge As for Hoover Dam, why do you insist on showing your ignorance on every subject under the sun? The fam is 45 ft thick at the surface and rarely has water up to that level. The bottom of the dam is 660 feet thick. Perhaps you'd care to explain to us how that compared to a concrete barge with a wall thickness of 18"? It's a ship, not a barge: https://en.wikipedia.org/wiki/SS_Palo_Alto Because you can use Google doesn't mean you know a damn thing you anti-intellectual. I'll give you half a point for getting the Alvord Bridge right, and a full point for getting Hoover Dam and most of the concrete boat right. However, I'll take off a point for exceeding your ration of insults allowed in a single posting. Please note that readers tend to eventually develop an immune response to your insults and that additional insults have little added effect. -- Jeff Liebermann PO Box 272 http://www.LearnByDestroying.com Ben Lomond CA 95005-0272 Skype: JeffLiebermann AE6KS 831-336-2558 |
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On Monday, June 7, 2021 at 9:15:19 p.m. UTC-4, wrote:
On Mon, 7 Jun 2021 16:06:05 -0700 (PDT), Tom Kunich wrote: Snipped However, I'll take off a point for exceeding your ration of insults allowed in a single posting. Please note that readers tend to eventually develop an immune response to your insults and that additional insults have little added effect. -- Jeff Liebermann PO Box 272 http://www.LearnByDestroying.com Ben Lomond CA 95005-0272 Skype: JeffLiebermann AE6KS 831-336-2558 I find it much easier to simply ignore his posts entirely. YMMV Cheers |
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On Mon, 7 Jun 2021 18:38:47 -0700 (PDT), Sir Ridesalot
wrote: On Monday, June 7, 2021 at 9:15:19 p.m. UTC-4, wrote: On Mon, 7 Jun 2021 16:06:05 -0700 (PDT), Tom Kunich wrote: Snipped However, I'll take off a point for exceeding your ration of insults allowed in a single posting. Please note that readers tend to eventually develop an immune response to your insults and that additional insults have little added effect. I find it much easier to simply ignore his posts entirely. YMMV Cheers I don't find it easier. Tom is not going to learn anything new or change in any way. I found a 15 year old Usenet posting where he acted much the same as today. I was busy for the last week and mostly avoided Tom and just about every other distraction. However, as I was finishing up, I couldn't resist taking a peek at R.B.T. and automatically corrected one of Tom's contrived pontifications. I've been doing this for so long, that responding has become a reflex action. I'm not programmed for ignoring stupidity and feel obligated to fix things. Ok, I'm addicted, which is why it's not easy for me. Ignoring Tom might work, but only if everyone does the same. That's unlikely to happen. As long as Tom monopolizes the bulk of the messages in R.B.T., it will be difficult for me to find a discussion thread that doesn't involve Tom in some manner. I might was well go away and do something else more useful. I'll give it another try and see if I can ignore Tom. However, don't be surprised if I sneak in a few corrections and bad humor. Drivel: How does one say YMMV (your mileage may vary) in metric units? -- Jeff Liebermann PO Box 272 http://www.LearnByDestroying.com Ben Lomond CA 95005-0272 Skype: JeffLiebermann AE6KS 831-336-2558 |
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On Monday, June 7, 2021 at 10:38:34 p.m. UTC-4, wrote:
On Mon, 7 Jun 2021 18:38:47 -0700 (PDT), Sir Ridesalot wrote: On Monday, June 7, 2021 at 9:15:19 p.m. UTC-4, wrote: On Mon, 7 Jun 2021 16:06:05 -0700 (PDT), Tom Kunich wrote: Snipped However, I'll take off a point for exceeding your ration of insults allowed in a single posting. Please note that readers tend to eventually develop an immune response to your insults and that additional insults have little added effect. I find it much easier to simply ignore his posts entirely. YMMV Cheers I don't find it easier. Tom is not going to learn anything new or change in any way. I found a 15 year old Usenet posting where he acted much the same as today. I was busy for the last week and mostly avoided Tom and just about every other distraction. However, as I was finishing up, I couldn't resist taking a peek at R.B.T. and automatically corrected one of Tom's contrived pontifications. I've been doing this for so long, that responding has become a reflex action. I'm not programmed for ignoring stupidity and feel obligated to fix things. Ok, I'm addicted, which is why it's not easy for me. Ignoring Tom might work, but only if everyone does the same. That's unlikely to happen. As long as Tom monopolizes the bulk of the messages in R.B.T., it will be difficult for me to find a discussion thread that doesn't involve Tom in some manner. I might was well go away and do something else more useful. I'll give it another try and see if I can ignore Tom. However, don't be surprised if I sneak in a few corrections and bad humor. Drivel: How does one say YMMV (your mileage may vary) in metric units? -- Jeff Liebermann PO Box 272 http://www.LearnByDestroying.com Ben Lomond CA 95005-0272 Skype: JeffLiebermann AE6KS 831-336-2558 YKmsMV? LOL Cheers |
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On 6/7/2021 9:38 PM, Jeff Liebermann wrote:
On Mon, 7 Jun 2021 18:38:47 -0700 (PDT), Sir Ridesalot wrote: On Monday, June 7, 2021 at 9:15:19 p.m. UTC-4, wrote: On Mon, 7 Jun 2021 16:06:05 -0700 (PDT), Tom Kunich wrote: Snipped However, I'll take off a point for exceeding your ration of insults allowed in a single posting. Please note that readers tend to eventually develop an immune response to your insults and that additional insults have little added effect. I find it much easier to simply ignore his posts entirely. YMMV Cheers I don't find it easier. Tom is not going to learn anything new or change in any way. I found a 15 year old Usenet posting where he acted much the same as today. I was busy for the last week and mostly avoided Tom and just about every other distraction. However, as I was finishing up, I couldn't resist taking a peek at R.B.T. and automatically corrected one of Tom's contrived pontifications. I've been doing this for so long, that responding has become a reflex action. I'm not programmed for ignoring stupidity and feel obligated to fix things. Ok, I'm addicted, which is why it's not easy for me. Ignoring Tom might work, but only if everyone does the same. That's unlikely to happen. As long as Tom monopolizes the bulk of the messages in R.B.T., it will be difficult for me to find a discussion thread that doesn't involve Tom in some manner. I might was well go away and do something else more useful. I'll give it another try and see if I can ignore Tom. However, don't be surprised if I sneak in a few corrections and bad humor. Drivel: How does one say YMMV (your mileage may vary) in metric units? At least RBT is better attended than Rec Autos which has become a wasteland. Even the always enlightening SteveW and TheRealBev hardy ever write now. -- Andrew Muzi www.yellowjersey.org/ Open every day since 1 April, 1971 |
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