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Post by c64 on Apr 15, 2015 10:51:37 GMT
Here is a picturr of a common (EU) tire de.m.wikipedia.org/w/index.php?title=Datei:Radial_Tire_(Structure).svg&lang=deSteel is drawn in blue. My favourite kind of tire I use since 1998 is the same but uses kevlar belts instead of steel belts. Everybody sais that it doesn't make any difference so I just waste money. But the handling of the car feels better. Could be other factors of my favourite brand but I don't care. I like them and had no tire failure ever since. I had blown my share of diagonals with farming equippment and broke two radial steel belts on my first car within a few years until I switched to kevlar. They are 40% more expensive but I belief they are worth it! an here is a picture of a common fire truck tire: selector.goodyeartrucktires.com/cfmx/web/truckblank/img/cutaways/g395_cut-and-text.jpgI've blown three sets of radials on the work van I drove for the last company I worked for. my truck just ground off the tread until I started buying real truck tires for it. Those look like a good a radial tire. And no steel where it doesn't belong  |
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Post by the light works on Apr 15, 2015 14:52:19 GMT
EDIT..... This post has been copied over from picture board.There was a thing that you should never put cross-ply and radial on the same axle. I have seen why.... I know why... As Cross-ply is almost extinct, I am wondering, is it worth re-trying that as a myth, to show "the youngsters" how bloody useless cross-ply was?... Does anyone still use cross-ply tyres?.. If so, why, .... and where...... Just as an indication. Cross-Ply.
The two side by side.
Undressed.....
Radial construction.
 I think, here, you can still get bias (cross) ply for antique car tires - though you can also get radials that look nearly identical. other than that, I think they are limited to heavy equipment tires. an I don't think they have installed a split rim or a "california rim" (similar but different) on anything since the 70s - so the only things with dangerous rims are very old. |
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Post by the light works on Apr 15, 2015 14:55:18 GMT
Cross-ply vs Radial. Now I was told they have different grip at different speeds. And that was why they were no good on the same axle. Never did find out which was which... As in which has better grip at slower, which is better at faster etc... I am beginning to wonder if that in its self isnt an actual myth, and that as Cross-Ply has become almost extinct, that Radial were just better tyres "back then" and that they have evolved even further now. I am wondering if... If, if you had developed Cross-ply further, would they have been better eventually than Radial. Its the old VHS vs Betamax question... And for the record, Betamax was better. the argument in the US against bias ply tires is that radials roll "easier" for better gas mileage. |
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Post by the light works on Apr 15, 2015 15:06:17 GMT
Tyres and Sparks. Well, they are rubber.... And rubber is an insulator. First question, what is the official description of Insulator to be used when asking this question... [From here on in, I am talking in quotes a lot, because these quotes are how most of us understand this subject, and how the few of us should investigate "what we know" to investigate this myth, so anything I "quote" is up for discussion, as it may just well be a misconception that we all take for granted?... ]Second question when does that *Not apply*. Third, obviously, *Compared to what* In answering the second, I have to wonder just how many products can be used to show that they insulate *Up to* a certain amount of sparks... Where that amount is the triangle of V=I/R, is it the current or voltage that breaks the insulation "rating" and starts to become conductive. Compared to what... We know a Faraday cage will keep you safe. So what else?... Would standing inside a "plastic" cage keep you safe?... And how thick would it need to be?... At what stage would the sparks be strong enough to think the surface of a plastic cage is better than air?... Has anyone on reading this far started to get the idea I am proposing they go talk to their friendly Van-De-Graph Generator friends and go borrow that lighting creating investigation facility again?.... At what point would we consider that stuff what they say, the only safe place in a lighting storm is hidden in the cupboard under the stairs with your Duvet over you head. Put your head between your knees And close you eyes Then you can kiss Your (A**h*le) goodbye... (Fallout calypso, Mike Harding.) The thing with that fire truck hitting an overhead power line that shorted out and set its tyres on fire. Just what would have prevented that being a problem. Bigger thick rubber sheet underneath the appliance?... Better road insulation rating? (the tarmac..) So does the type of ground you are on change things. Is a big sheet of concrete flooring or roadway an insulator?.... power line trucks with "hot work" buckets have a 10 foot dielectric section at the base of the boom. that is the only way I can think of to be sure you can get the bucket energized without blowing up the truck. tires are required to have a minimum level of conuctivity to dissipate static electricity. beyond that, there is "breakdown voltage" which, as you surmised is the voltage at which the insulator gives it up as a lost cause. concrete is considered to be conudctive. our house earthing stanard now is to connect to the rebar in the concrete foundation. I can say for a fact that at power line voltages, even minimal ones, asphalt is also conductive. the protection a car gives from lightning is neither faraday cage protection nor tire insulation protection. it would be better described as skin effect protection. when the lightning strikes, it hits the roof of the car first, then the steel provides a low enough impedance path around the body of the car that it isn't tempted to look for anything inside the shell. so the only thing that really would have allowed the fire truck to contact the wires without being blown up is a high enough rated dielectric pad. - and I'm not sure one of those exists. our basic rule for power line safety is "I wouldn't touch it with a ten foot pole" |
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Post by the light works on Apr 15, 2015 15:08:59 GMT
Those look like a good a radial tire. And no steel where it doesn't belong all the belting and casing are steel. the sidewalls have to be very stiff to prevent blowing out the sidewalls. |
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Post by c64 on Apr 15, 2015 21:23:00 GMT
Those look like a good a radial tire. And no steel where it doesn't belong all the belting and casing are steel. the sidewalls have to be very stiff to prevent blowing out the sidewalls. Not at all. Since the sides are deformed in many directions, steel will break soon due to metal fatigue. The clasdic tires are rounded to keep the stress in an even direction and spread the wear evenly. Modern ones have straight sides to enhance stability for a better handling of the car. The sides are made out of a harder rubber and reinforced by fabric. |
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Post by the light works on Apr 15, 2015 22:38:34 GMT
all the belting and casing are steel. the sidewalls have to be very stiff to prevent blowing out the sidewalls. Not at all. Since the sides are deformed in many directions, steel will break soon due to metal fatigue. The clasdic tires are rounded to keep the stress in an even direction and spread the wear evenly. Modern ones have straight sides to enhance stability for a better handling of the car. The sides are made out of a harder rubber and reinforced by fabric. for cars, maybe. remember, that I put all the weight of your car on each one of my tires. directly off the sidewall: tread 4 plies steel, sidewall 1 ply steel. |
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Post by kharnynb on Apr 16, 2015 4:37:46 GMT
No legally sold tires in Finland have a sidewall with steel, and i doubt it is more than 1 or 2 US-only manufacturers that still make anything like that. Over here it is roughly fabric liner for vehicles with 1 ton or less per tyre, then kevlar liner for heavier ones.
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Post by silverdragon on Apr 16, 2015 7:08:03 GMT
Tyres and Sparks. the protection a car gives from lightning is neither faraday cage protection nor tire insulation protection. it would be better described as skin effect protection. when the lightning strikes, it hits the roof of the car first, then the steel provides a low enough impedance path around the body of the car that it isn't tempted to look for anything inside the shell. so the only thing that really would have allowed the fire truck to contact the wires without being blown up is a high enough rated dielectric pad. - and I'm not sure one of those exists. our basic rule for power line safety is "I wouldn't touch it with a ten foot pole" In my own job, low slung power lines are a problem. I only do the job when the load will fit under existing lines. I DO NOT do jobs where lines have to be either dismantled or shifted... I dont trust people with long poles holding up the wire?... |
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Post by the light works on Apr 16, 2015 13:44:41 GMT
In my own job, low slung power lines are a problem. I only do the job when the load will fit under existing lines. I DO NOT do jobs where lines have to be either dismantled or shifted... I dont trust people with long poles holding up the wire?... my parents had a telephone wire hanging a bit low over one of their bulk mulch piles. they had to set up a custom made 20' pole to lift it about a half inch to allow the truck to back in an unload. here, I don't think the power companies allow power lines to be lifted - they must be shut down and moved to allow extreme overheight loads - but I think they are also a minimum of 25 feet clearance over anywhere a motor vehicle might reasonably be expected to drive. service drops must be at least 18 feet clearance. |
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Post by c64 on Apr 16, 2015 15:49:55 GMT
No legally sold tires in Finland have a sidewall with steel, and i doubt it is more than 1 or 2 US-only manufacturers that still make anything like that. Over here it is roughly fabric liner for vehicles with 1 ton or less per tyre, then kevlar liner for heavier ones. There are more companies that make them, even in the EU. The famous "balloon tires" are still legal on tractor trailers since those can't be faster than 80kph. On motor-vehicles, the limit seems to be under 60kph since only 25kph farming and construction equipment has the classic diagonal steel belts since they have their advantages on very uneven terrain. The 63kph class uses radial tires only. Also, tires can have multiple sandwiched layers of nylon even for high load ratings. They are much cheaper than kevlar but won't last long in rough terrain. And the old "balloon tires" are even cheaper, the only reason why they are still around because they are not (yet) banned for slow trailers and even slower vehicles. |
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Post by the light works on Apr 16, 2015 16:06:51 GMT
No legally sold tires in Finland have a sidewall with steel, and i doubt it is more than 1 or 2 US-only manufacturers that still make anything like that. Over here it is roughly fabric liner for vehicles with 1 ton or less per tyre, then kevlar liner for heavier ones. There are more companies that make them, even in the EU. The famous "balloon tires" are still legal on tractor trailers since those can't be faster than 80kph. On motor-vehicles, the limit seems to be under 60kph since only 25kph farming and construction equipment has the classic diagonal steel belts since they have their advantages on very uneven terrain. The 63kph class uses radial tires only. Also, tires can have multiple sandwiched layers of nylon even for high load ratings. They are much cheaper than kevlar but won't last long in rough terrain. And the old "balloon tires" are even cheaper, the only reason why they are still around because they are not (yet) banned for slow trailers and even slower vehicles. unless your definition of balloon tire is different than the US definition, you really have strange tire ratings. this is what balloon tire means in the US:  |
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Post by the light works on Apr 19, 2015 14:58:43 GMT
doesn't mean the rubber isn't also carrying a substantial current. but I just opened a tire thread, maybe this should get added. wood is also conductive at those voltages. Not just at those voltages, that's how moisture detectors for firewood work. The probe voltage usually is 6V or less. Even the driest wood I can find in the attic has some reading and those beam are in a dry place for over 100 years! Of course there is some power released directly inside the rubber. They must have less than a Gigaohm (according to standards) but a few hundred Watt won't give you instant fire. never been assigned to babysit a downed power line while you waited for the power company to come along and turn it off, have you? |
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Post by c64 on Apr 19, 2015 22:47:30 GMT
There are more companies that make them, even in the EU. The famous "balloon tires" are still legal on tractor trailers since those can't be faster than 80kph. On motor-vehicles, the limit seems to be under 60kph since only 25kph farming and construction equipment has the classic diagonal steel belts since they have their advantages on very uneven terrain. The 63kph class uses radial tires only. Also, tires can have multiple sandwiched layers of nylon even for high load ratings. They are much cheaper than kevlar but won't last long in rough terrain. And the old "balloon tires" are even cheaper, the only reason why they are still around because they are not (yet) banned for slow trailers and even slower vehicles. unless your definition of balloon tire is different than the US definition, you really have strange tire ratings. this is what balloon tire means in the US: Correct. They are great for rough terrain because they usually are filled with very little pressure. On farming tractors (the 25 kph max kind) they are sometimes filled with water for extra traction. You don't need to install concrete weights. I prefere barrels and a PTO pump. You can dump ballast anywhere and pick up ballast very conviniently. Also you can refill the water tubs for cattle on your way back from the field. |
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Post by c64 on Apr 19, 2015 22:51:21 GMT
Not just at those voltages, that's how moisture detectors for firewood work. The probe voltage usually is 6V or less. Even the driest wood I can find in the attic has some reading and those beam are in a dry place for over 100 years! Of course there is some power released directly inside the rubber. They must have less than a Gigaohm (according to standards) but a few hundred Watt won't give you instant fire. never been assigned to babysit a downed power line while you waited for the power company to come along and turn it off, have you? No need to. High tension lines are monitored automatically and for very high tension, the system triggers before the wire hits the ground. And the low voltage stuff (240/400V) is underground, not many exeptions left. A HV line can set tires on fire, but for the tire itself it takes time until it is real hot. It would blow before it is hot enough to catch fire. What sets a tire on fire is the electric arc through the air which curves round the rubber. Hotter than the surface of the sun, it takes only a few seconds until ,he surface burns leaving the insides of the tire cold and sturdy. |
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Post by GTCGreg on Apr 19, 2015 23:09:54 GMT
High tension lines are monitored automatically and for very high tension, the system triggers before the wire hits the ground. And the low voltage stuff (240/400V) is underground, not many exeptions left. Not around here. I've watched a 12.5KV line arcing and sparking on the ground for hours before the power company showed up to take care of it. And that was only after one resident called in to report a fire. Then the electric company truck came in following the fire trucks. As for the low voltage stuff (120-480), while a lot is now underground, the majority is still overhead. |
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Post by the light works on Apr 20, 2015 2:32:06 GMT
unless your definition of balloon tire is different than the US definition, you really have strange tire ratings. this is what balloon tire means in the US: Correct. They are great for rough terrain because they usually are filled with very little pressure. On farming tractors (the 25 kph max kind) they are sometimes filled with water for extra traction. You don't need to install concrete weights. I prefere barrels and a PTO pump. You can dump ballast anywhere and pick up ballast very conviniently. Also you can refill the water tubs for cattle on your way back from the field. ah. in the US, a tractor trailer refers to this:  |
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Post by the light works on Apr 20, 2015 2:34:56 GMT
never been assigned to babysit a downed power line while you waited for the power company to come along and turn it off, have you? No need to. High tension lines are monitored automatically and for very high tension, the system triggers before the wire hits the ground. And the low voltage stuff (240/400V) is underground, not many exeptions left. A HV line can set tires on fire, but for the tire itself it takes time until it is real hot. It would blow before it is hot enough to catch fire. What sets a tire on fire is the electric arc through the air which curves round the rubber. Hotter than the surface of the sun, it takes only a few seconds until ,he surface burns leaving the insides of the tire cold and sturdy. here, if the fault is not great enough, the breakers won't open. - and typically the breakers will automatically reclose three or more times just in case it was just a tree branch shorting out the line. |
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Post by c64 on Apr 20, 2015 5:59:31 GMT
Correct. They are great for rough terrain because they usually are filled with very little pressure. On farming tractors (the 25 kph max kind) they are sometimes filled with water for extra traction. You don't need to install concrete weights. I prefere barrels and a PTO pump. You can dump ballast anywhere and pick up ballast very conviniently. Also you can refill the water tubs for cattle on your way back from the field. ah. in the US, a tractor trailer refers to this: Yes, legal for the trailer except for twin wheels or twin axles but illegal on the tracor. Usually used for construction but not for pure cargo purooses. |
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Post by silverdragon on Apr 20, 2015 6:32:13 GMT
Not just at those voltages, that's how moisture detectors for firewood work. The probe voltage usually is 6V or less. Even the driest wood I can find in the attic has some reading and those beam are in a dry place for over 100 years! Of course there is some power released directly inside the rubber. They must have less than a Gigaohm (according to standards) but a few hundred Watt won't give you instant fire. never been assigned to babysit a downed power line while you waited for the power company to come along and turn it off, have you? Which is why I dont do the have to move them out of the way thing. I waited four hours one time, put a call through to find out why no one was there, "Oh, we didnt get the message through" I had been sat there for four hours for (xyz)ing NOTHING..!! |
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