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Let the Laughing Begin
Yesterday I went on a long enough ride and the weather report turned out to be incorrect enough that I was close to heat prostration near the end.
I hit a stone in the road that was invisible and it gave me a flat. As I was trying to figure out how to make the particular CO2 filler in that seat pack to work I punctured the canister and lost one of my two CO2 tubes. Opening the front tire to remove the inner tube and replace it with the new tube a black guy who looked nearly homeless came by and said that he had a patch kit if I needed it. I thanked him but without a pump I couldn't find any leaks to patch. When the front tube came out it was a Performance butyl tube. They were available in a 30, a 40 and a 60 mm stem length. I have bought the latex tubes because they were available in 51 mm stems. The back (which was losing air about the same as the front) is latex. So my tires not losing air plainly isn't because of the material of the tubes. My suspicion is the pump meter. I bought a new Silca professional pump from Andrew and it has a new (and probably much better) pressure gauge on it. This allows me to fill the tire up properly and to test the pressure more accurately than most pumps. So it probably is pump and not inner tube material related. Now don't say I lacked the courage to publicly correct myself when I think I was wrong. How many of you can say the same thing - John and Frank? |
Let the Laughing Begin
On Monday, September 4, 2017 at 1:17:23 PM UTC-7, Joerg wrote:
On 2017-09-04 13:00, wrote: Yesterday I went on a long enough ride and the weather report turned out to be incorrect enough that I was close to heat prostration near the end. I went up the MTB trail towards Placerville. Gulped down the contents of all three 28oz water bottles which kept me humming. However, the air was so bad from nearby wildfires that if wasn't super fun. To relax we hung out at a horse ranch. I hit a stone in the road that was invisible and it gave me a flat. Should have used thick thorn-resistant tubes. Wouldn't have helped. There was a rock shard driven threw the gatorskin at it's toughest spot. How can a "professional" pump be so wrong? I bought a $20 Zefal floor pump for $20 at Walmart and its gauge tracked a commercial grade pressure gauge in my lab very well. The professional is the one that's accurate and the cheaper one that was both showing the wrong pressure and probably letting pressure bleed off through the cheaper filler nozzle. Now don't say I lacked the courage to publicly correct myself when I think I was wrong. How many of you can say the same thing - John and Frank? My wife would do that for me if I didn't :-) Tell me about it. |
Let the Laughing Begin
On 2017-09-04 14:01, wrote:
On Monday, September 4, 2017 at 1:17:23 PM UTC-7, Joerg wrote: On 2017-09-04 13:00, wrote: Yesterday I went on a long enough ride and the weather report turned out to be incorrect enough that I was close to heat prostration near the end. I went up the MTB trail towards Placerville. Gulped down the contents of all three 28oz water bottles which kept me humming. However, the air was so bad from nearby wildfires that if wasn't super fun. To relax we hung out at a horse ranch. I hit a stone in the road that was invisible and it gave me a flat. Should have used thick thorn-resistant tubes. Wouldn't have helped. There was a rock shard driven threw the gatorskin at it's toughest spot. Through the running surface of a Gatorskin? That must have been a rock from hell. Sidewall, different thing. Gatorskins are totally flimsy there which is one reason why I abandoned them. How can a "professional" pump be so wrong? I bought a $20 Zefal floor pump for $20 at Walmart and its gauge tracked a commercial grade pressure gauge in my lab very well. The professional is the one that's accurate and the cheaper one that was both showing the wrong pressure and probably letting pressure bleed off through the cheaper filler nozzle. I'd have returned it to the store. A pump is supposed to show steady pressure when you stop pumping and not leak. [...] -- Regards, Joerg http://www.analogconsultants.com/ |
Let the Laughing Begin
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Let the Laughing Begin
On Mon, 4 Sep 2017 14:01:39 -0700 (PDT), wrote:
The professional is the one that's accurate and the cheaper one that was both showing the wrong pressure and probably letting pressure bleed off through the cheaper filler nozzle. Here's my bicycle pump tester: http://802.11junk.com/jeffl/pics/bicycles/misc/slides/Bicycle%20pump%20pressure%20gauge.html I scribbled a little about how it's used in a previous postings: https://groups.google.com/d/msg/rec.bicycles.tech/YsqvNggfDDM/CoySfXtGAQAJ https://groups.google.com/d/msg/rec.bicycles.tech/YsqvNggfDDM/XeXJLe5kAQAJ For a leakdown test, I attach a small pressure vessel to one port, and pump up the pressure with a bicycle pump attached to the other port. Then, I watch the pump gauge to see if it remains stable. If the test gauge leaks, I paint the plumbing with bubble mix looking for the source of the air leaks. If the gauge itself is suspect, I take it apart and check the mechanism for leaks. -- Jeff Liebermann 150 Felker St #D http://www.LearnByDestroying.com Santa Cruz CA 95060 http://802.11junk.com Skype: JeffLiebermann AE6KS 831-336-2558 |
Let the Laughing Begin
On Monday, September 4, 2017 at 9:25:51 PM UTC-7, Jeff Liebermann wrote:
On Mon, 4 Sep 2017 14:01:39 -0700 (PDT), wrote: The professional is the one that's accurate and the cheaper one that was both showing the wrong pressure and probably letting pressure bleed off through the cheaper filler nozzle. Here's my bicycle pump tester: http://802.11junk.com/jeffl/pics/bicycles/misc/slides/Bicycle%20pump%20pressure%20gauge.html I scribbled a little about how it's used in a previous postings: https://groups.google.com/d/msg/rec.bicycles.tech/YsqvNggfDDM/CoySfXtGAQAJ https://groups.google.com/d/msg/rec.bicycles.tech/YsqvNggfDDM/XeXJLe5kAQAJ For a leakdown test, I attach a small pressure vessel to one port, and pump up the pressure with a bicycle pump attached to the other port. Then, I watch the pump gauge to see if it remains stable. If the test gauge leaks, I paint the plumbing with bubble mix looking for the source of the air leaks. If the gauge itself is suspect, I take it apart and check the mechanism for leaks. Well, that certainly seems a better method than getting a good pump to begin with. |
Let the Laughing Begin
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Let the Laughing Begin
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Let the Laughing Begin
On Tuesday, September 5, 2017 at 8:43:40 AM UTC-7, Frank Krygowski wrote:
On 9/4/2017 4:00 PM, wrote: [I responded to this earlier, and it shows up in my "Sent" folder, but never made it to the group. I don't know why. Maybe it had something to do with my internet speed test showing approximately zero for upload speed? Thanks, AT&T.] Now don't say I lacked the courage to publicly correct myself when I think I was wrong. How many of you can say the same thing - John and Frank? I've done that several times. Oddly enough, I did it once in error. There was a long flame-fest including an alias-using individual of renowned obnoxiousness. (He stopped posting here years ago.) Part of it referred to a bike-related technical equation in a website run by a pretty well known bike tech guy. Anyway, after considerable debate, I accepted Mr. Obnoxious's claim that the equation was in error. I said here that he was right and I (and the equation) was wrong. Mr. Obnoxious was so surprised he promised to stop online abuse - a promise he quickly broke. Then I emailed the website guy, whom I've corresponded with and met a couple times. He pointed out that no, his equation was correct and showed why. So Mr. Obnoxious was wrong indeed. (I think the issue was Mr. O changed the point of contention from force to stress, and it slipped by me.) Anyway, I had apologized here, but my apology was in error. Given the climate of the online discussion, I decided to just let it go. While repairing the flat I got the other day, it turned out that the second tube had two small holes. I can't tell what caused this. It was like a wire flat but it was across the contact surface of the tire. So it too two patches to repair. The original tube had a very large pinch flat from hitting that rock on the road for it was a throw-away. The inner tube in the box wouldn't fit in my seat pack so I opened it and it was a butyl tube as well. Looking at the site where I bought it these were the cheapest inner tubes there. But I distinctly remember ordering the latex tubes because at the time they were the only tubes with 51 mm stems. These have 51 mm stems even though they're butyl. So looking through my pile of spares they are all butyl and there are no latex tubes at all. That means that my back tire with the 51 mm stem sticking out of it is no doubt butyl as well. I can only imagine that they had a mistake on the website that has since been corrected. This again hardens my suspicion that the pressure changes in my tires before my new pump had to do with the cheap floor pumps inaccurate pressure gauges and the leakage around that "easy operation" connector with the throw handle. |
Let the Laughing Begin
On Tue, 5 Sep 2017 07:04:03 -0700 (PDT), wrote:
On Monday, September 4, 2017 at 9:25:51 PM UTC-7, Jeff Liebermann wrote: On Mon, 4 Sep 2017 14:01:39 -0700 (PDT), wrote: The professional is the one that's accurate and the cheaper one that was both showing the wrong pressure and probably letting pressure bleed off through the cheaper filler nozzle. Here's my bicycle pump tester: http://802.11junk.com/jeffl/pics/bicycles/misc/slides/Bicycle%20pump%20pressure%20gauge.html I scribbled a little about how it's used in a previous postings: https://groups.google.com/d/msg/rec.bicycles.tech/YsqvNggfDDM/CoySfXtGAQAJ https://groups.google.com/d/msg/rec.bicycles.tech/YsqvNggfDDM/XeXJLe5kAQAJ For a leakdown test, I attach a small pressure vessel to one port, and pump up the pressure with a bicycle pump attached to the other port. Then, I watch the pump gauge to see if it remains stable. If the test gauge leaks, I paint the plumbing with bubble mix looking for the source of the air leaks. If the gauge itself is suspect, I take it apart and check the mechanism for leaks. Well, that certainly seems a better method than getting a good pump to begin with. Quantity is my substitute for quality. When I tested my collection of floor and frame pumps, I found a few defective pumps and a few inaccurate gauges. I don't recall the numbers, but one gauge read 8 lbs low for a 60 lb tire pressure. Cleaning the crud out of the mechanism most fixed that. I don't think I own anything that might resemble a "good pump". This was from 3 years ago: http://802.11junk.com/jeffl/pics/bicycles/misc/slides/bicycle-pumps.html I now have about twice as many frame pumps. I also have 4 working floor pumps, 2 sick floor pumps, 1 worthless foot pump, and maybe a dozen assorted pencil, analog, and digital gauges. The various cheap automotive type digital gauges seem to be the most consistent and accurate, but also have mechanical problem, such as fitting only Schrader valves or a leaky fit. Maybe, some day I'll buy a "good pump" and recycle all the junk pumps. A proper dead weight pressure gauge tester/calibrator is not in my budget (although I could probably build one). Incidentally, when I go for rides these daze, I generally throw the bicycle into my Subaru and drive to where I want to ride. Before leaving, I usually top off my leaky tires with some air from a cheap 12V automotive air tire pump. The one I have has an automatic shutoff when it reaches a set pressure. I just set the dial, start the air compressor, and I'm ready to ride when it's done. The problem is that it's horribly inaccurate. The dial settings and built in pressure gauge don't agree and are rather inaccurate. However, they are fairly consistent, so I just calibrated the readings and scribbled a calibration chart. After that, frame and floor pumps seem so uncivilized. At one time, I proposed a portable bicycle tire inflator consisting of something like the automotive automatic shutoff compressor that I'm using, with an added LiIon rechargeable battery. Or maybe powered instead by a model airplane gasoline engine. I think I can make it small enough to be fairly flat and pocket size. A little marketing research indicated that nobody I asked would pay money for such a thing but might consider building one from a kit. Very strange but I decided that it was too risky and let the idea die a natural death. -- Jeff Liebermann 150 Felker St #D http://www.LearnByDestroying.com Santa Cruz CA 95060 http://802.11junk.com Skype: JeffLiebermann AE6KS 831-336-2558 |
Let the Laughing Begin
|
Let the Laughing Begin
On Tuesday, September 5, 2017 at 8:43:40 AM UTC-7, Frank Krygowski wrote:
On 9/4/2017 4:00 PM, wrote: [I responded to this earlier, and it shows up in my "Sent" folder, but never made it to the group. I don't know why. Maybe it had something to do with my internet speed test showing approximately zero for upload speed? Thanks, AT&T.] Now don't say I lacked the courage to publicly correct myself when I think I was wrong. How many of you can say the same thing - John and Frank? I've done that several times. Oddly enough, I did it once in error. "This book contains at least one error, but this may be it." - Peter van der Linden, "Expert C Programming" (LOL yea, rite, Peter! Cute quote tho- :) |
Let the Laughing Begin
On Tue, 5 Sep 2017 07:04:41 -0700 (PDT), wrote:
On Monday, September 4, 2017 at 7:32:25 PM UTC-7, John B. wrote: On Mon, 4 Sep 2017 13:00:34 -0700 (PDT), wrote: Yesterday I went on a long enough ride and the weather report turned out to be incorrect enough that I was close to heat prostration near the end. I hit a stone in the road that was invisible and it gave me a flat. As I was trying to figure out how to make the particular CO2 filler in that seat pack to work I punctured the canister and lost one of my two CO2 tubes. Opening the front tire to remove the inner tube and replace it with the new tube a black guy who looked nearly homeless came by and said that he had a patch kit if I needed it. I thanked him but without a pump I couldn't find any leaks to patch. When the front tube came out it was a Performance butyl tube. They were available in a 30, a 40 and a 60 mm stem length. I have bought the latex tubes because they were available in 51 mm stems. The back (which was losing air about the same as the front) is latex. So my tires not losing air plainly isn't because of the material of the tubes. My suspicion is the pump meter. I bought a new Silca professional pump from Andrew and it has a new (and probably much better) pressure gauge on it. This allows me to fill the tire up properly and to test the pressure more accurately than most pumps. So it probably is pump and not inner tube material related. Now don't say I lacked the courage to publicly correct myself when I think I was wrong. How many of you can say the same thing - John and Frank? Actually I don't remember ever saying that you failed to correct yourself. If memory serves what I've said was that "you are wrong". And as usual you didn't know what you were talking about. As someone wrote, "Reality is anything you want it to be. Just close your eyes and let your imagination run wild." -- Cheers, John B. |
Let the Laughing Begin
On Tue, 05 Sep 2017 09:52:07 -0700, Jeff Liebermann
wrote: On Tue, 5 Sep 2017 07:04:03 -0700 (PDT), wrote: On Monday, September 4, 2017 at 9:25:51 PM UTC-7, Jeff Liebermann wrote: On Mon, 4 Sep 2017 14:01:39 -0700 (PDT), wrote: The professional is the one that's accurate and the cheaper one that was both showing the wrong pressure and probably letting pressure bleed off through the cheaper filler nozzle. Here's my bicycle pump tester: http://802.11junk.com/jeffl/pics/bicycles/misc/slides/Bicycle%20pump%20pressure%20gauge.html I scribbled a little about how it's used in a previous postings: https://groups.google.com/d/msg/rec.bicycles.tech/YsqvNggfDDM/CoySfXtGAQAJ https://groups.google.com/d/msg/rec.bicycles.tech/YsqvNggfDDM/XeXJLe5kAQAJ For a leakdown test, I attach a small pressure vessel to one port, and pump up the pressure with a bicycle pump attached to the other port. Then, I watch the pump gauge to see if it remains stable. If the test gauge leaks, I paint the plumbing with bubble mix looking for the source of the air leaks. If the gauge itself is suspect, I take it apart and check the mechanism for leaks. Well, that certainly seems a better method than getting a good pump to begin with. Quantity is my substitute for quality. When I tested my collection of floor and frame pumps, I found a few defective pumps and a few inaccurate gauges. I don't recall the numbers, but one gauge read 8 lbs low for a 60 lb tire pressure. Cleaning the crud out of the mechanism most fixed that. I don't think I own anything that might resemble a "good pump". This was from 3 years ago: http://802.11junk.com/jeffl/pics/bicycles/misc/slides/bicycle-pumps.html I now have about twice as many frame pumps. I also have 4 working floor pumps, 2 sick floor pumps, 1 worthless foot pump, and maybe a dozen assorted pencil, analog, and digital gauges. The various cheap automotive type digital gauges seem to be the most consistent and accurate, but also have mechanical problem, such as fitting only Schrader valves or a leaky fit. Maybe, some day I'll buy a "good pump" and recycle all the junk pumps. A proper dead weight pressure gauge tester/calibrator is not in my budget (although I could probably build one). Incidentally, when I go for rides these daze, I generally throw the bicycle into my Subaru and drive to where I want to ride. Before leaving, I usually top off my leaky tires with some air from a cheap 12V automotive air tire pump. The one I have has an automatic shutoff when it reaches a set pressure. I just set the dial, start the air compressor, and I'm ready to ride when it's done. The problem is that it's horribly inaccurate. The dial settings and built in pressure gauge don't agree and are rather inaccurate. However, they are fairly consistent, so I just calibrated the readings and scribbled a calibration chart. After that, frame and floor pumps seem so uncivilized. At one time, I proposed a portable bicycle tire inflator consisting of something like the automotive automatic shutoff compressor that I'm using, with an added LiIon rechargeable battery. Or maybe powered instead by a model airplane gasoline engine. I think I can make it small enough to be fairly flat and pocket size. A little marketing research indicated that nobody I asked would pay money for such a thing but might consider building one from a kit. Very strange but I decided that it was too risky and let the idea die a natural death. I've always believed that a "good pump" was one with which one could inflate the desired tire to the desired pressure :-) -- Cheers, John B. |
Let the Laughing Begin
On Wed, 06 Sep 2017 13:30:25 +0700, John B.
wrote: On Tue, 05 Sep 2017 09:52:07 -0700, Jeff Liebermann wrote: At one time, I proposed a portable bicycle tire inflator consisting of something like the automotive automatic shutoff compressor that I'm using, with an added LiIon rechargeable battery. Or maybe powered instead by a model airplane gasoline engine. I think I can make it small enough to be fairly flat and pocket size. A little marketing research indicated that nobody I asked would pay money for such a thing but might consider building one from a kit. Very strange but I decided that it was too risky and let the idea die a natural death. I've always believed that a "good pump" was one with which one could inflate the desired tire to the desired pressure :-) Sigh. Inflate the desired tire at what temperature, with how much effort, how quickly, to what accuracy, how big a tire, etc? What works well for a road bicycle, might not be so good inflating an automobile tire. What works in the shop, may not be so good during a ride. Of course, there are specialized bicycle pumps optimized for these and other purposes and conditions. My idea of a "good pump" is one that will do an adequate job of inflating everything from a high pressure racing tire (multistage pump), to an air mattress (large volume piston or vane pump). It might look a bit weird, have capabilities I might rarely use, probably expensive, but will work for anything that needs inflation. Here's one application for an air pump with which I'm currently working: https://www.amazon.com/Carburetor-detector-Replaces-Tillotson-243-504/dp/B06Y542R9S Yes, it's an air pump. It's used to apply pressure to the carburetor fuel inlet on a 2 stroke engine (chain saw) to determine if the needle valve is working properly and not leaking. Apply pressure and it should open the needle valve at about 15 psi. Let it bleed down, and it should close again at 5 psi. Pressurized to 10 psi and dunk the carburetor into a bowl of water while looking for leaks (air bubbles). A "good pump" should be able to do this as well. The problem here is that this is what I want, not what the GUM (great unwashed masses) are will to buy. That makes it a "good pump" but only for me. You may have other ideas. -- Jeff Liebermann 150 Felker St #D http://www.LearnByDestroying.com Santa Cruz CA 95060 http://802.11junk.com Skype: JeffLiebermann AE6KS 831-336-2558 |
Let the Laughing Begin
On Tuesday, September 5, 2017 at 9:52:10 AM UTC-7, Jeff Liebermann wrote:
On Tue, 5 Sep 2017 07:04:03 -0700 (PDT), wrote: On Monday, September 4, 2017 at 9:25:51 PM UTC-7, Jeff Liebermann wrote: On Mon, 4 Sep 2017 14:01:39 -0700 (PDT), wrote: The professional is the one that's accurate and the cheaper one that was both showing the wrong pressure and probably letting pressure bleed off through the cheaper filler nozzle. Here's my bicycle pump tester: http://802.11junk.com/jeffl/pics/bicycles/misc/slides/Bicycle%20pump%20pressure%20gauge.html I scribbled a little about how it's used in a previous postings: https://groups.google.com/d/msg/rec.bicycles.tech/YsqvNggfDDM/CoySfXtGAQAJ https://groups.google.com/d/msg/rec.bicycles.tech/YsqvNggfDDM/XeXJLe5kAQAJ For a leakdown test, I attach a small pressure vessel to one port, and pump up the pressure with a bicycle pump attached to the other port. Then, I watch the pump gauge to see if it remains stable. If the test gauge leaks, I paint the plumbing with bubble mix looking for the source of the air leaks. If the gauge itself is suspect, I take it apart and check the mechanism for leaks. Well, that certainly seems a better method than getting a good pump to begin with. Quantity is my substitute for quality. When I tested my collection of floor and frame pumps, I found a few defective pumps and a few inaccurate gauges. I don't recall the numbers, but one gauge read 8 lbs low for a 60 lb tire pressure. Cleaning the crud out of the mechanism most fixed that. I don't think I own anything that might resemble a "good pump". This was from 3 years ago: http://802.11junk.com/jeffl/pics/bicycles/misc/slides/bicycle-pumps.html I now have about twice as many frame pumps. I also have 4 working floor pumps, 2 sick floor pumps, 1 worthless foot pump, and maybe a dozen assorted pencil, analog, and digital gauges. The various cheap automotive type digital gauges seem to be the most consistent and accurate, but also have mechanical problem, such as fitting only Schrader valves or a leaky fit. Maybe, some day I'll buy a "good pump" and recycle all the junk pumps. A proper dead weight pressure gauge tester/calibrator is not in my budget (although I could probably build one). Incidentally, when I go for rides these daze, I generally throw the bicycle into my Subaru and drive to where I want to ride. Before leaving, I usually top off my leaky tires with some air from a cheap 12V automotive air tire pump. The one I have has an automatic shutoff when it reaches a set pressure. I just set the dial, start the air compressor, and I'm ready to ride when it's done. The problem is that it's horribly inaccurate. The dial settings and built in pressure gauge don't agree and are rather inaccurate. However, they are fairly consistent, so I just calibrated the readings and scribbled a calibration chart. After that, frame and floor pumps seem so uncivilized. At one time, I proposed a portable bicycle tire inflator consisting of something like the automotive automatic shutoff compressor that I'm using, with an added LiIon rechargeable battery. Or maybe powered instead by a model airplane gasoline engine. I think I can make it small enough to be fairly flat and pocket size. A little marketing research indicated that nobody I asked would pay money for such a thing but might consider building one from a kit. Very strange but I decided that it was too risky and let the idea die a natural death. -- Jeff Liebermann 150 Felker St #D http://www.LearnByDestroying.com Santa Cruz CA 95060 http://802.11junk.com Skype: JeffLiebermann AE6KS 831-336-2558 Well, fortunately for us all, the exact pressure that yer tires are at is simply not that problematic. It is simply not like saddle height. If my roadbike tires are at 120 one day and 115 the next and 110 the next, well that's just okay. Below 110 I'll notice and think they feel a little soft and slow. On the mtn bike, I'll pump them up to 55-60, usually, and if they're at 50 or even 45 one day well I'll have a little softer ride that day and yea I'll work just a bit harder uphill, then get a just a bit better grip on the way back down. |
Let the Laughing Begin
Quantity is my substitute for quality. So, to know the exact pressure at which his tires are inflated, Tom should own a dozen guages, apply them all, and average the results? |
Let the Laughing Begin
On Wednesday, September 6, 2017 at 8:54:56 AM UTC-7, Jeff Liebermann wrote:
On Wed, 06 Sep 2017 13:30:25 +0700, John B. wrote: On Tue, 05 Sep 2017 09:52:07 -0700, Jeff Liebermann wrote: At one time, I proposed a portable bicycle tire inflator consisting of something like the automotive automatic shutoff compressor that I'm using, with an added LiIon rechargeable battery. Or maybe powered instead by a model airplane gasoline engine. I think I can make it small enough to be fairly flat and pocket size. A little marketing research indicated that nobody I asked would pay money for such a thing but might consider building one from a kit. Very strange but I decided that it was too risky and let the idea die a natural death. I've always believed that a "good pump" was one with which one could inflate the desired tire to the desired pressure :-) Sigh. Inflate the desired tire at what temperature, with how much effort, how quickly, to what accuracy, how big a tire, etc? What works well for a road bicycle, might not be so good inflating an automobile tire. What works in the shop, may not be so good during a ride. Of course, there are specialized bicycle pumps optimized for these and other purposes and conditions. My idea of a "good pump" is one that will do an adequate job of inflating everything from a high pressure racing tire (multistage pump), to an air mattress (large volume piston or vane pump). It might look a bit weird, have capabilities I might rarely use, probably expensive, but will work for anything that needs inflation. Here's one application for an air pump with which I'm currently working: https://www.amazon.com/Carburetor-detector-Replaces-Tillotson-243-504/dp/B06Y542R9S Yes, it's an air pump. It's used to apply pressure to the carburetor fuel inlet on a 2 stroke engine (chain saw) to determine if the needle valve is working properly and not leaking. Apply pressure and it should open the needle valve at about 15 psi. Let it bleed down, and it should close again at 5 psi. Pressurized to 10 psi and dunk the carburetor into a bowl of water while looking for leaks (air bubbles). A "good pump" should be able to do this as well. The problem here is that this is what I want, not what the GUM (great unwashed masses) are will to buy. That makes it a "good pump" but only for me. You may have other ideas. Absolutely Jeff. MTB tires will not inflate well on my Silca Pro road bike pump. It takes 25 pumps to inflate a 23 to 110. MTB's definitely need a much higher volume pump and they don't need to get above 80 psi at the highest. |
Let the Laughing Begin
On Wed, 6 Sep 2017 11:02:12 -0700 (PDT), Doug Landau
wrote: Quantity is my substitute for quality. So, to know the exact pressure at which his tires are inflated, Tom should own a dozen guages, apply them all, and average the results? Sure. The errors tend to random, some high, some low, some large, some small, etc. When a large number of measurements are averaged, the result tends to be fairly close to reality. At least that's what some climate researchers claimed when they averaged the results of many prehistoric temperature and CO2 proxies, each of which were suspected of being inaccurate, and produced an average which the was declared accurate. Actually, it would be more interesting if we took pressure readings at various times of the day. If you set your tire pressure to some number on a cold morning, and then go for a ride in the hot sun, your tire pressure will increase. Strictly speaking, one needs to be seated on the bicycle in order to get an accurate measurement or proper setting. That might be a bit awkward unless you're a contortionist. It might be instructive (and amusing) to attach a BlueGoof wireless tire pressure gauge and data logger to a wheel and watch the variations in pressure as the bicycle bounces down the road or does aerobatics. I suspect that you'll find large variations, which should make you wonder why anyone bothers to set the tire pressure more accurately than hard, firm, mush, soft, and flat. Math, numbers, formulas, and calculations: http://www.velonews.com/2017/03/bikes-and-tech/technical-faq-science-tire-pressure-rim-width-heat-buildup_433214 Math hates me. -- Jeff Liebermann 150 Felker St #D http://www.LearnByDestroying.com Santa Cruz CA 95060 http://802.11junk.com Skype: JeffLiebermann AE6KS 831-336-2558 |
Let the Laughing Begin
On 06/09/2017 2:59 PM, Jeff Liebermann wrote:
On Wed, 6 Sep 2017 11:02:12 -0700 (PDT), Doug Landau wrote: Quantity is my substitute for quality. So, to know the exact pressure at which his tires are inflated, Tom should own a dozen guages, apply them all, and average the results? Sure. The errors tend to random, some high, some low, some large, some small, etc. When a large number of measurements are averaged, the result tends to be fairly close to reality. At least that's what some climate researchers claimed when they averaged the results of many prehistoric temperature and CO2 proxies, each of which were suspected of being inaccurate, and produced an average which the was declared accurate. Actually, it would be more interesting if we took pressure readings at various times of the day. If you set your tire pressure to some number on a cold morning, and then go for a ride in the hot sun, your tire pressure will increase. Strictly speaking, one needs to be seated on the bicycle in order to get an accurate measurement or proper setting. That might be a bit awkward unless you're a contortionist. It might be instructive (and amusing) to attach a BlueGoof wireless tire pressure gauge and data logger to a wheel and watch the variations in pressure as the bicycle bounces down the road or does aerobatics. I suspect that you'll find large variations, which should make you wonder why anyone bothers to set the tire pressure more accurately than hard, firm, mush, soft, and flat. Math, numbers, formulas, and calculations: http://www.velonews.com/2017/03/bikes-and-tech/technical-faq-science-tire-pressure-rim-width-heat-buildup_433214 Math hates me. Or just buy a decent pump and forget about it. |
Let the Laughing Begin
On Wednesday, September 6, 2017 at 12:07:47 PM UTC-7, Duane wrote:
On 06/09/2017 2:59 PM, Jeff Liebermann wrote: On Wed, 6 Sep 2017 11:02:12 -0700 (PDT), Doug Landau wrote: Quantity is my substitute for quality. So, to know the exact pressure at which his tires are inflated, Tom should own a dozen guages, apply them all, and average the results? Sure. The errors tend to random, some high, some low, some large, some small, etc. When a large number of measurements are averaged, the result tends to be fairly close to reality. At least that's what some climate researchers claimed when they averaged the results of many prehistoric temperature and CO2 proxies, each of which were suspected of being inaccurate, and produced an average which the was declared accurate. Actually, it would be more interesting if we took pressure readings at various times of the day. If you set your tire pressure to some number on a cold morning, and then go for a ride in the hot sun, your tire pressure will increase. Strictly speaking, one needs to be seated on the bicycle in order to get an accurate measurement or proper setting. That might be a bit awkward unless you're a contortionist. It might be instructive (and amusing) to attach a BlueGoof wireless tire pressure gauge and data logger to a wheel and watch the variations in pressure as the bicycle bounces down the road or does aerobatics. I suspect that you'll find large variations, which should make you wonder why anyone bothers to set the tire pressure more accurately than hard, firm, mush, soft, and flat. Math, numbers, formulas, and calculations: http://www.velonews.com/2017/03/bikes-and-tech/technical-faq-science-tire-pressure-rim-width-heat-buildup_433214 Math hates me. Or just buy a decent pump and forget about it. Better yet just use any floor pump with a guage and forget about it. |
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On Wednesday, September 6, 2017 at 2:02:15 PM UTC-4, Doug Landau wrote:
Quantity is my substitute for quality. So, to know the exact pressure at which his tires are inflated, Tom should own a dozen guages, apply them all, and average the results? Yes, of course. But keep in mind that each time a gauge is used, it causes a tiny bit of air to escape, which results in a tiny pressure loss. So rather than a simple average, it would be wise to plot the results in order, then do a best-fit computation to help account for that gradual pressure loss. If you want to be accurate, that is. ;-) - Frank Krygowski |
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On Wednesday, September 6, 2017 at 2:59:25 PM UTC-4, Jeff Liebermann wrote:
If you set your tire pressure to some number on a cold morning, and then go for a ride in the hot sun, your tire pressure will increase. As mentioned in the past, I blew out a new and expensive tubular by leaving the bike parked in the hot southern sun. There was a huge bang, and I found a big hole in the center of the tread right at the top. Shoulda used fenders, I guess. - Frank Krygowski |
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On Wednesday, September 6, 2017 at 12:07:47 PM UTC-7, Duane wrote:
Or just buy a decent pump and forget about it. As Jeff asked - what is a "decent pump"? A pump that works good on a high pressure racing bike takes forever to inflate an MTB tire. With almost all of the pumps these days using that awful filler valve https://tinyurl.com/y84dcpqn simply isn't right for other applications. |
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Doug Landau wrote:
On Wednesday, September 6, 2017 at 12:07:47 PM UTC-7, Duane wrote: On 06/09/2017 2:59 PM, Jeff Liebermann wrote: On Wed, 6 Sep 2017 11:02:12 -0700 (PDT), Doug Landau wrote: Quantity is my substitute for quality. So, to know the exact pressure at which his tires are inflated, Tom should own a dozen guages, apply them all, and average the results? Sure. The errors tend to random, some high, some low, some large, some small, etc. When a large number of measurements are averaged, the result tends to be fairly close to reality. At least that's what some climate researchers claimed when they averaged the results of many prehistoric temperature and CO2 proxies, each of which were suspected of being inaccurate, and produced an average which the was declared accurate. Actually, it would be more interesting if we took pressure readings at various times of the day. If you set your tire pressure to some number on a cold morning, and then go for a ride in the hot sun, your tire pressure will increase. Strictly speaking, one needs to be seated on the bicycle in order to get an accurate measurement or proper setting. That might be a bit awkward unless you're a contortionist. It might be instructive (and amusing) to attach a BlueGoof wireless tire pressure gauge and data logger to a wheel and watch the variations in pressure as the bicycle bounces down the road or does aerobatics. I suspect that you'll find large variations, which should make you wonder why anyone bothers to set the tire pressure more accurately than hard, firm, mush, soft, and flat. Math, numbers, formulas, and calculations: http://www.velonews.com/2017/03/bikes-and-tech/technical-faq-science-tire-pressure-rim-width-heat-buildup_433214 Math hates me. Or just buy a decent pump and forget about it. Better yet just use any floor pump with a guage and forget about it. That's my plan. So far so good. -- duane |
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On Wed, 06 Sep 2017 08:54:53 -0700, Jeff Liebermann
wrote: On Wed, 06 Sep 2017 13:30:25 +0700, John B. wrote: On Tue, 05 Sep 2017 09:52:07 -0700, Jeff Liebermann wrote: At one time, I proposed a portable bicycle tire inflator consisting of something like the automotive automatic shutoff compressor that I'm using, with an added LiIon rechargeable battery. Or maybe powered instead by a model airplane gasoline engine. I think I can make it small enough to be fairly flat and pocket size. A little marketing research indicated that nobody I asked would pay money for such a thing but might consider building one from a kit. Very strange but I decided that it was too risky and let the idea die a natural death. I've always believed that a "good pump" was one with which one could inflate the desired tire to the desired pressure :-) Sigh. Inflate the desired tire at what temperature, with how much effort, how quickly, to what accuracy, how big a tire, etc? What works well for a road bicycle, might not be so good inflating an automobile tire. What works in the shop, may not be so good during a ride. Of course, there are specialized bicycle pumps optimized for these and other purposes and conditions. My idea of a "good pump" is one that will do an adequate job of inflating everything from a high pressure racing tire (multistage pump), to an air mattress (large volume piston or vane pump). It might look a bit weird, have capabilities I might rarely use, probably expensive, but will work for anything that needs inflation. You missed the "desired tire to the desired pressure" ;-? Here's one application for an air pump with which I'm currently working: https://www.amazon.com/Carburetor-detector-Replaces-Tillotson-243-504/dp/B06Y542R9S Yes, it's an air pump. It's used to apply pressure to the carburetor fuel inlet on a 2 stroke engine (chain saw) to determine if the needle valve is working properly and not leaking. Apply pressure and it should open the needle valve at about 15 psi. Let it bleed down, and it should close again at 5 psi. Pressurized to 10 psi and dunk the carburetor into a bowl of water while looking for leaks (air bubbles). A "good pump" should be able to do this as well. Yup, we used to do that. Blow into the fuel line. While nobody's cheeks were calibrated in psi it did tell you if the needle valve was leaking. One did have to spit a bit to get the gasoline taste out of your mouth though. :-) The problem here is that this is what I want, not what the GUM (great unwashed masses) are will to buy. That makes it a "good pump" but only for me. You may have other ideas. -- Cheers, John B. |
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On Tuesday, September 5, 2017 at 11:26:55 PM UTC-7, John B. wrote:
On Tue, 5 Sep 2017 07:04:41 -0700 (PDT), wrote: On Monday, September 4, 2017 at 7:32:25 PM UTC-7, John B. wrote: On Mon, 4 Sep 2017 13:00:34 -0700 (PDT), wrote: Yesterday I went on a long enough ride and the weather report turned out to be incorrect enough that I was close to heat prostration near the end. I hit a stone in the road that was invisible and it gave me a flat. As I was trying to figure out how to make the particular CO2 filler in that seat pack to work I punctured the canister and lost one of my two CO2 tubes.. Opening the front tire to remove the inner tube and replace it with the new tube a black guy who looked nearly homeless came by and said that he had a patch kit if I needed it. I thanked him but without a pump I couldn't find any leaks to patch. When the front tube came out it was a Performance butyl tube. They were available in a 30, a 40 and a 60 mm stem length. I have bought the latex tubes because they were available in 51 mm stems. The back (which was losing air about the same as the front) is latex. So my tires not losing air plainly isn't because of the material of the tubes. My suspicion is the pump meter. I bought a new Silca professional pump from Andrew and it has a new (and probably much better) pressure gauge on it. This allows me to fill the tire up properly and to test the pressure more accurately than most pumps. So it probably is pump and not inner tube material related. Now don't say I lacked the courage to publicly correct myself when I think I was wrong. How many of you can say the same thing - John and Frank? Actually I don't remember ever saying that you failed to correct yourself. If memory serves what I've said was that "you are wrong". And as usual you didn't know what you were talking about. As someone wrote, "Reality is anything you want it to be. Just close your eyes and let your imagination run wild." -- Cheers, John B. LOL Pat Tillman! |
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On Wed, 6 Sep 2017 17:29:34 -0700 (PDT), Doug Landau
wrote: On Tuesday, September 5, 2017 at 11:26:55 PM UTC-7, John B. wrote: On Tue, 5 Sep 2017 07:04:41 -0700 (PDT), wrote: On Monday, September 4, 2017 at 7:32:25 PM UTC-7, John B. wrote: On Mon, 4 Sep 2017 13:00:34 -0700 (PDT), wrote: Yesterday I went on a long enough ride and the weather report turned out to be incorrect enough that I was close to heat prostration near the end. I hit a stone in the road that was invisible and it gave me a flat. As I was trying to figure out how to make the particular CO2 filler in that seat pack to work I punctured the canister and lost one of my two CO2 tubes. Opening the front tire to remove the inner tube and replace it with the new tube a black guy who looked nearly homeless came by and said that he had a patch kit if I needed it. I thanked him but without a pump I couldn't find any leaks to patch. When the front tube came out it was a Performance butyl tube. They were available in a 30, a 40 and a 60 mm stem length. I have bought the latex tubes because they were available in 51 mm stems. The back (which was losing air about the same as the front) is latex. So my tires not losing air plainly isn't because of the material of the tubes. My suspicion is the pump meter. I bought a new Silca professional pump from Andrew and it has a new (and probably much better) pressure gauge on it. This allows me to fill the tire up properly and to test the pressure more accurately than most pumps. So it probably is pump and not inner tube material related. Now don't say I lacked the courage to publicly correct myself when I think I was wrong. How many of you can say the same thing - John and Frank? Actually I don't remember ever saying that you failed to correct yourself. If memory serves what I've said was that "you are wrong". And as usual you didn't know what you were talking about. As someone wrote, "Reality is anything you want it to be. Just close your eyes and let your imagination run wild." -- Cheers, John B. LOL Pat Tillman! :-) But even a casual reading of the "social networks" seems to prove my point :-) -- Cheers, John B. |
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As someone wrote, "Reality is anything you want it to be. Just close your eyes and let your imagination run wild." -- Cheers, John B. LOL Pat Tillman! :-) But even a casual reading of the "social networks" seems to prove my point :-) Actually I was reacting to what I wanted to react to not exactly what you said. What trips me out is when people say you make your own reality. Certainly it is a lovely thought and a lovely thing to say to someone seeking inspiration, and certainly the Olympic gold medalist subscribes to the theory. But where does that leave the silver medalist? Who believed and believed and believed and busted and busted and busted their ass? Derek Porter was my first rowing hero. He was in an 8 that got a gold in 92, and was world champ in 93, IIRC, and thot 96 was his year. Look at him try to hold back the tears on the podium in 96* and again in 00. https://www.youtube.com/watch?v=wViOIIh7pUU https://www.google.com/search?q=Dere... cw4dTFyxb5M: *It is well worth watching the whole race, for other reasons. Cheers |
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On Wed, 6 Sep 2017 15:07:43 -0400, Duane
wrote: Or just buy a decent pump and forget about it. I Googled for "decent pump" and didn't find anything that meets all my requirements. Also, I won't forget this. I smell a profit here. Perhaps I should also weaponize my bicycle pump? "High pressure, multiple-stage air pump with valve body inlet port arrangement" https://www.google.com/patents/US8047818 "One application where high pressure air is required is with high performance air rifles. Such rifles rival performance of light caliber firearms, and may yield muzzle velocities approaching 1200 fps. In order to achieve such velocities, an air reserve tank is coupled to the rifle that provides air pressure in the 2000 psi to 3600 psi range." If some vehicle gets within 3ft of me, I just pull out my weaponized universal bicycle pump, and blow a hole in their 20 gauge sheet metal armor. That would seem far more effective and satisfying than kicking their door as they pass. Yeah, I want one. Ummm.... what caliber would you consider to be "decent"? -- Jeff Liebermann 150 Felker St #D http://www.LearnByDestroying.com Santa Cruz CA 95060 http://802.11junk.com Skype: JeffLiebermann AE6KS 831-336-2558 |
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On Wednesday, September 6, 2017 at 3:08:09 PM UTC-7, wrote:
On Wednesday, September 6, 2017 at 12:07:47 PM UTC-7, Duane wrote: Or just buy a decent pump and forget about it. As Jeff asked - what is a "decent pump"? A pump that works good on a high pressure racing bike takes forever to inflate an MTB tire. With almost all of the pumps these days using that awful filler valve https://tinyurl.com/y84dcpqn simply isn't right for other applications. I thot we already established that when you put down the $$ for a floor pump that has a good reputation, and is not toward the lower end of the range, still you get a gauge that is 7psi off. IOW there are no decent pumps on the market; they all cheese out on the gauge. |
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On Wed, 6 Sep 2017 15:08:05 -0700 (PDT), wrote:
On Wednesday, September 6, 2017 at 12:07:47 PM UTC-7, Duane wrote: Or just buy a decent pump and forget about it. As Jeff asked - what is a "decent pump"? A pump that works good on a high pressure racing bike takes forever to inflate an MTB tire. With almost all of the pumps these days using that awful filler valve https://tinyurl.com/y84dcpqn simply isn't right for other applications. The air chuck (head) certainly could use a few lessons from the automobile mechanics, which use a proper locking air chuck something like these: https://static.grainger.com/rp/s/is/image/Grainger/2HKY3_AS01 https://veesun.com/images/air_chuck/731423.jpg They grip well, don't fall off, don't blow off at 150 psi, and usually survive getting trampled. However, they're for Schrader valves only and are not made for Presta. The closest equivalent is this device: https://www.excelsports.com/main.asp?page=8&description=Hiro+Side+Lever+Lockin g+Disc+Chuck&vendorCode=SILCA&major=12&minor=4 Yes, it's USD$100.00 for a locking Presta air chuck. You can find something cheaper, but it's not locking: http://www.lezyne.com/product-dpumps-acc-slipchk.php About $10. I have two of them. They work for about 20-30 inflations before the rubber O-ring wears out. Notice that it includes 6 replacement O-rings. More Presta tire chucks: https://www.google.com/search?tbm=isch&q=locking+presta+tire+chuck You can find other Presta heads, but they will probably be in the form of a combination Schrader and Presta head, which is the problem. When one combines the two valve types in a single head, the only mechanism that works for both is the "hole in the rubber plug" type that grips the threads on the outside of the valve stem. One possible solution for Presta is to use a Schrader to Presta adapter, but those are awkward and clumsy and tend to fall off if left on the valve: https://www.youtube.com/watch?v=ncY1PEgSbI0 In my never humble opinion, the best solution is a pump head with only one type of valve arrangement. The hose and head should be removable from the pump using standard pneumatic fittings. If a floor pump, the gauge should be near the handle, where I can see it, not on the floor, where I need my distance eyeglasses to read the dial. http://www.bermstyle.com/wp-content/uploads/2014/12/20141116-turbocharger-pump-6281.jpg Extra credit for selecting large numbers and high visibility colors for the dial, instead of a black dial with a red pointer, which is almost invisible in the dark: https://s3-eu-west-1.amazonaws.com/images.linnlive.com/9aee59d2c18ef6fce9ea759285f794e3/0f3a7dbd-0a6f-4bf9-9ff5-50c64bc3c06f.jpg I'm sure there are more obvious improvements but these will suffice for now. As for tire pump displacement vs pressure, take a look at a better than average hydraulic wood splitter. All these use two stage hydraulic pumps. There first stage offers high volume, low pressure, to rapidly move the splitting wedge from the open loading position, to where it begins to hit the log. Once it hits the log, it switches to low volume, high pressure, which is what's needed to bisect the log. The same could be done with a bicycle pump design. The bicycle pump would initially be in high volume, low pressure mode up to maybe 10-15 psi, where it would switch to low volume high pressure to reach operating pressure. -- Jeff Liebermann 150 Felker St #D http://www.LearnByDestroying.com Santa Cruz CA 95060 http://802.11junk.com Skype: JeffLiebermann AE6KS 831-336-2558 |
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On Thu, 07 Sep 2017 07:23:07 +0700, John B.
wrote: Sigh. Inflate the desired tire at what temperature, with how much effort, how quickly, to what accuracy, how big a tire, etc? (...) You missed the "desired tire to the desired pressure" ;-? No I didn't. The word "Inflate" assumes that pressure is checked (unless you subscribe to my hard, firm, soft, mush, flat empirical standard for tire inflation without numbers. Here's one application for an air pump with which I'm currently working: https://www.amazon.com/Carburetor-detector-Replaces-Tillotson-243-504/dp/B06Y542R9S Yes, it's an air pump. It's used to apply pressure to the carburetor fuel inlet on a 2 stroke engine (chain saw) to determine if the needle valve is working properly and not leaking. Apply pressure and it should open the needle valve at about 15 psi. Let it bleed down, and it should close again at 5 psi. Pressurized to 10 psi and dunk the carburetor into a bowl of water while looking for leaks (air bubbles). A "good pump" should be able to do this as well. Yup, we used to do that. Blow into the fuel line. While nobody's cheeks were calibrated in psi it did tell you if the needle valve was leaking. One did have to spit a bit to get the gasoline taste out of your mouth though. :-) Ummm... perhaps you shouldn't inhale with the hose in your mouth? I built a fairly simple contrivance to avoid having to pay $40 for a cheap Chinese clone of the real pressure tester. For a pressure pump, I used a plastic baking syringe: https://www.google.com/search?q=plastic+baking+syringe&tbm=isch The rubber seal was the first to fall apart followed by the crumbling of the clear plastic. I used vinyl hose instead of Trygon fuel line, which seems to be softening from ethynol exposure. Maybe I should just give up and spend the $40. (Note to self: Universal air pump design should have a Tygon hose option). -- Jeff Liebermann 150 Felker St #D http://www.LearnByDestroying.com Santa Cruz CA 95060 http://802.11junk.com Skype: JeffLiebermann AE6KS 831-336-2558 |
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On Wed, 06 Sep 2017 13:26:51 +0700, John B.
wrote: As someone wrote, "Reality is anything you want it to be. Yep. Reality is in the mind of the beholder. Which is the real me? http://www.learnbydestroying.com/jeffl/pics/jeffl/jeffl-wolf.gif Just close your eyes and let your imagination run wild." Not while I'm riding or typing. Besides, the statement is backwards. I close my eyes BECAUSE my imagination has gone wildly out of control. -- Jeff Liebermann 150 Felker St #D http://www.LearnByDestroying.com Santa Cruz CA 95060 http://802.11junk.com Skype: JeffLiebermann AE6KS 831-336-2558 |
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On Wed, 6 Sep 2017 19:06:34 -0700 (PDT), Doug Landau
wrote: As someone wrote, "Reality is anything you want it to be. Just close your eyes and let your imagination run wild." -- Cheers, John B. LOL Pat Tillman! :-) But even a casual reading of the "social networks" seems to prove my point :-) Actually I was reacting to what I wanted to react to not exactly what you said. What trips me out is when people say you make your own reality. Certainly it is a lovely thought and a lovely thing to say to someone seeking inspiration, and certainly the Olympic gold medalist subscribes to the theory. But where does that leave the silver medalist? Who believed and believed and believed and busted and busted and busted their ass? Derek Porter was my first rowing hero. He was in an 8 that got a gold in 92, and was world champ in 93, IIRC, and thot 96 was his year. Look at him try to hold back the tears on the podium in 96* and again in 00. https://www.youtube.com/watch?v=wViOIIh7pUU https://www.google.com/search?q=Dere... cw4dTFyxb5M: *It is well worth watching the whole race, for other reasons. Cheers And I was thinking of the Facebook account that "went viral" recently here about the newly constructed, not yet finished "high-rise" that was going to fall over. See http://tinyurl.com/y83kdemv I remember reading somewhere that: "The potential collective intelligence of a human group is exponentially proportional to group size, however in practice the actual collective intelligence that is achieved by a group is inversely proportional to group size. There is a huge delta between potential collective intelligence and actual collective intelligence in practice. In other words, when it comes to collective intelligence, the whole has the potential to be smarter than the sum of its parts, but in practice it is usually dumber." to quote http://tinyurl.com/yd68nx2 -- Cheers, John B. |
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On Wed, 06 Sep 2017 20:39:07 -0700, Jeff Liebermann
wrote: On Thu, 07 Sep 2017 07:23:07 +0700, John B. wrote: Sigh. Inflate the desired tire at what temperature, with how much effort, how quickly, to what accuracy, how big a tire, etc? (...) You missed the "desired tire to the desired pressure" ;-? No I didn't. The word "Inflate" assumes that pressure is checked (unless you subscribe to my hard, firm, soft, mush, flat empirical standard for tire inflation without numbers. Ever do much with inflatable mattresses, used by some campers? Or those little inflatable raft thing that kids use in the back yard pool? Or Inflatable boats. No pressure gauges for those.... and having used an inflatable boat for a year or so I can assure you that when you are putt-putting a mile out into the bay to get to your yacht you do have a certain amount of interest in the boat being inflated to "the desired pressure" :-) Here's one application for an air pump with which I'm currently working: https://www.amazon.com/Carburetor-detector-Replaces-Tillotson-243-504/dp/B06Y542R9S Yes, it's an air pump. It's used to apply pressure to the carburetor fuel inlet on a 2 stroke engine (chain saw) to determine if the needle valve is working properly and not leaking. Apply pressure and it should open the needle valve at about 15 psi. Let it bleed down, and it should close again at 5 psi. Pressurized to 10 psi and dunk the carburetor into a bowl of water while looking for leaks (air bubbles). A "good pump" should be able to do this as well. Yup, we used to do that. Blow into the fuel line. While nobody's cheeks were calibrated in psi it did tell you if the needle valve was leaking. One did have to spit a bit to get the gasoline taste out of your mouth though. :-) Ummm... perhaps you shouldn't inhale with the hose in your mouth? Well, most people were bright enough not to do that, some without being told, too. I built a fairly simple contrivance to avoid having to pay $40 for a cheap Chinese clone of the real pressure tester. For a pressure pump, I used a plastic baking syringe: https://www.google.com/search?q=plastic+baking+syringe&tbm=isch The rubber seal was the first to fall apart followed by the crumbling of the clear plastic. I used vinyl hose instead of Trygon fuel line, which seems to be softening from ethynol exposure. Maybe I should just give up and spend the $40. (Note to self: Universal air pump design should have a Tygon hose option). -- Cheers, John B. |
Let the Laughing Begin
On Thu, 07 Sep 2017 13:22:05 +0700, John B.
wrote: On Wed, 06 Sep 2017 20:39:07 -0700, Jeff Liebermann wrote: On Thu, 07 Sep 2017 07:23:07 +0700, John B. wrote: Sigh. Inflate the desired tire at what temperature, with how much effort, how quickly, to what accuracy, how big a tire, etc? (...) You missed the "desired tire to the desired pressure" ;-? No I didn't. The word "Inflate" assumes that pressure is checked (unless you subscribe to my hard, firm, soft, mush, flat empirical standard for tire inflation without numbers. Ever do much with inflatable mattresses, used by some campers? Or those little inflatable raft thing that kids use in the back yard pool? Or Inflatable boats. No pressure gauges for those.... and having used an inflatable boat for a year or so I can assure you that when you are putt-putting a mile out into the bay to get to your yacht you do have a certain amount of interest in the boat being inflated to "the desired pressure" :-) Sure. When one inflates a vessel with a large volume and semi-rigid structure, there's quite a large difference in air volume between maximum and minimum inflation. Plenty of room to experiment and fairly easy to determine if it's hard, firm, soft, mush, or flat. However, as the vessel volume becomes smaller and the structure become more rigid, that allowable sloppiness becomes small. A small blast of air from the inflator, could mean over-inflation. Blowing some air out the Presta valve to clear out the dirt, might drop the tire to well below operational pressure. Incidentally, I've been working erratically on the design of several inflatable portable antenna structures. Something like these but smaller and lighter: http://www.ltaprojects.com Inflation pressure largely determines the load capacity of the structure. Underinflation can cause buckling. Therefore, it's important to set the pressure accurately. Much of the basic design closely resembles an inflatable air mattress sitting on end. Ummm... perhaps you shouldn't inhale with the hose in your mouth? Well, most people were bright enough not to do that, some without being told, too. I just demonstrated that I'm not one of the bright ones. I've been having problems seeing the computer screen. The characters all seem to look blurry. Various reading glasses didn't help much. I just wasted an hour poking around the monitor trying to determine the cause. After essentially giving up, I decided that maybe I should give the "Auto" button on the monitor a try. That fixed the problem in a few seconds. Moral: When looking for the obscure, be sure to also check the obvious. -- Jeff Liebermann 150 Felker St #D http://www.LearnByDestroying.com Santa Cruz CA 95060 http://802.11junk.com Skype: JeffLiebermann AE6KS 831-336-2558 |
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On Thu, 07 Sep 2017 11:04:20 +0700, John B.
wrote: "The potential collective intelligence of a human group is exponentially proportional to group size, however in practice the actual collective intelligence that is achieved by a group is inversely proportional to group size. There is a huge delta between potential collective intelligence and actual collective intelligence in practice. In other words, when it comes to collective intelligence, the whole has the potential to be smarter than the sum of its parts, but in practice it is usually dumber." to quote http://tinyurl.com/yd68nx2 Collective intelligence is also linear. If one person can do a specific job in 1 hr, two people will take 2 hrs, three people will take 3 hrs, four people will take 4 hrs, etc. -- Jeff Liebermann 150 Felker St #D http://www.LearnByDestroying.com Santa Cruz CA 95060 http://802.11junk.com Skype: JeffLiebermann AE6KS 831-336-2558 |
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On Thu, 07 Sep 2017 00:21:24 -0700, Jeff Liebermann
wrote: On Thu, 07 Sep 2017 13:22:05 +0700, John B. wrote: On Wed, 06 Sep 2017 20:39:07 -0700, Jeff Liebermann wrote: On Thu, 07 Sep 2017 07:23:07 +0700, John B. wrote: Sigh. Inflate the desired tire at what temperature, with how much effort, how quickly, to what accuracy, how big a tire, etc? (...) You missed the "desired tire to the desired pressure" ;-? No I didn't. The word "Inflate" assumes that pressure is checked (unless you subscribe to my hard, firm, soft, mush, flat empirical standard for tire inflation without numbers. Ever do much with inflatable mattresses, used by some campers? Or those little inflatable raft thing that kids use in the back yard pool? Or Inflatable boats. No pressure gauges for those.... and having used an inflatable boat for a year or so I can assure you that when you are putt-putting a mile out into the bay to get to your yacht you do have a certain amount of interest in the boat being inflated to "the desired pressure" :-) Sure. When one inflates a vessel with a large volume and semi-rigid structure, there's quite a large difference in air volume between maximum and minimum inflation. Plenty of room to experiment and fairly easy to determine if it's hard, firm, soft, mush, or flat. However, as the vessel volume becomes smaller and the structure become more rigid, that allowable sloppiness becomes small. A small blast of air from the inflator, could mean over-inflation. Blowing some air out the Presta valve to clear out the dirt, might drop the tire to well below operational pressure. Incidentally, I've been working erratically on the design of several inflatable portable antenna structures. Something like these but smaller and lighter: http://www.ltaprojects.com Inflation pressure largely determines the load capacity of the structure. Underinflation can cause buckling. Therefore, it's important to set the pressure accurately. Much of the basic design closely resembles an inflatable air mattress sitting on end. I would think that temperature would have a rather large effect on this sort of thing but I suspect that an automatic air pressure system wouldn't be difficult to arrange. Ummm... perhaps you shouldn't inhale with the hose in your mouth? Well, most people were bright enough not to do that, some without being told, too. I just demonstrated that I'm not one of the bright ones. I've been having problems seeing the computer screen. The characters all seem to look blurry. Various reading glasses didn't help much. I just wasted an hour poking around the monitor trying to determine the cause. After essentially giving up, I decided that maybe I should give the "Auto" button on the monitor a try. That fixed the problem in a few seconds. Moral: When looking for the obscure, be sure to also check the obvious. -- Cheers, John B. |
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