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#41
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torque wrench issues
On Sun, 30 Apr 2017 22:10:43 +0100, "Ian Field"
wrote: "AMuzi" wrote in message news On 4/30/2017 3:30 PM, Ian Field wrote: "AMuzi" wrote in message news On 4/30/2017 12:01 PM, Ian Field wrote: wrote in message ... On Sat, 29 Apr 2017 19:53:16 +0100, "Ian Field" wrote: wrote in message ... On Tue, 25 Apr 2017 20:16:22 +0100, "Benderthe.evilrobot" wrote: "John B Slocomb" wrote in message ... On Mon, 24 Apr 2017 22:17:14 -0400, wrote: On Tue, 25 Apr 2017 07:42:21 +0700, John B Slocomb wrote: On Mon, 24 Apr 2017 19:51:41 +0100, "Benderthe.evilrobot" wrote: wrote in message ... On Sun, 23 Apr 2017 22:06:05 +0100, "Benderthe.evilrobot" wrote: "Emanuel Berg" wrote in message ... I finally got the 1/2" torque wrench, 28-210 Nm, not even made in China, but in Taiwan! Eh... I guess it depends who you ask if that is China or not It has a locking screw, a torque setting handle, a scale (Nm as well as "FT-LB", some English unit I take it?) - it also as a locking lever on top just like an ordinary ratchet, so it can go both ways, clockwise and anti-clockwise. The torques only work in the clockwise direction. So if the locking (ratchet) lever is set the other way, it is just a ratchet, right? Well, in the manual it says: Note: Never use the torque wrench to undo nuts, bolts or other fasteners as this will damage the ratchet mechanism and the calibrated settings. So how does that add up? Is it only OK to use the anti-clockwise pull to insert things, which would require a left thread? (And it would be just a long shaft, with the torque not in effect.) As for me, I don't plan using it for anything but as a torque, because I have other, less expensive ratchets and spanners to do the everyday stuff. But of course, I'd like to know what it means. It also came with a certificate with data on the calibration and in the manual it says it should be recalibrated at least every 12 months. Calibration is irrelevant if you don't follow the rules to the letter. Most torque settings I've seen were for dry threads - any stray lubricant and you might even twist the end off at the correct torque. --- This email has been checked for viruses by AVG. http://www.avg.com Torque specs vary considerably by application. Some are given as clean and dry, some are given as lubricated with oil - some are given cold, and others hot. That said, I personally have never run across a torque spec that was so "close to the edge" that torqing with "stray lubrication" would cause immediate failure of the bolt by twisting off the end. However, that said, most of my wrenching has not been on bicycles but on automobiles and agricultural and construction equipment which may be slightly more "overengineered" or "overbuilt" Bicycles tend to have less things you can twist the end off. Its common on motorcycles, but mainly pulling the threads out of alloy castings. Its pretty rare to strip an engine down so far that you can put the castings in degreasing plant - torquing the engine case bolts with oil left in the holes is a very good chance of stripping the threads. As for stripping engine bolts, the Honda factory used to install fasteners so tight that a normal person couldn't get them out without an"impact driver". A tool that I never even saw before the Japanese invasion. The lock washers were very effective where used, and the Phipips style bolts were incapable of delivering enough torque to breat them loose without camming out - the Hammer Impact driver solved that problem I believe I've read that the "Phillips" headed screws in a Japanese motorcycle are not actually "Phillips" but some Japanese standard that didn't quite match the screwdrivers we had in the U.S. Which probably didn't help either :-) That's the *whole* cause - just grind a tiny bit off the point of the screwdriver bit and it fits just right. The bits on my Impact driver fit perfectly without grinding. Note I said Philips "style" (I know, I mis-spelled it) bolts. Some of the early Jap stuff didn't use Cadmium plated bolts either - W10 imploded and I had to start over with a replacement news account. So back to old name. The japs were the worst of the lot for cadmium plated fasteners. The very toxic cadmium rubs off on your hands and is cumulative in the body - it causes such acute osteoporosis; you can end up fracturing ribs just by coughing. In the UK - nickel plated fasteners became fashionable about the 80s. They didn't do much about cadmium plated chassis in electronic equipment until RoHS. AFAIK: cadmium batteries are exempt from RoHS - but they've more or less vanished from the shops anyway. Cadmium is very nasty - wash your hands after handling anything plated with it! from Cadmium, A Health Hazard Surface Treatment C. Rehm ESG Einsteinstr. 174 D-81675 Munich, Germany An object containing cadmium is not especially injurious to health on its own. No risk is involved simply by touching it. A potential hazard occurs, however, when such objects are processed and high temperatures are generated. Cadmium plating rubs off on your hands whenever you handle cadmium plated parts and assemblies. Many years ago they even used it on electronic component leads to prevent oxidation - they used more aggressive fluxes in those days. Welding cad plated sheet steel is particularly dangerous - the cadmium is vapourised and becomes airborne. Usually the osteoporosis takes decades to start crippling the sufferer - but I've heard of a repair technician dropping dead after a couple of years from fumes using low melting point cadmium based solder. The specific mode of death wasn't announced. The Japanese know all about it, they discharged industrial effluent containing cadmium into heavily fished costal waters. They even have a name for the disease - itai itai byo. apparently its the noise sufferers make in their death throes. As I mentioned previously - bones become so weak and brittle, you can fracture ribs just by coughing. Well then avoid it as you wish. Many of us recognize the difference between metals and reactive metallic organic compounds. Zinc rich tablets are popular for symptoms of herpes simplex and yet no one welds galvanize steel a second time. Zinc can't be that toxic - its a usual ingredient of baby powder. Never heard of any warnings against welding zinc passivated steel - only know of cadmium plating being very dangerous. Fumes of burning zinc make your knees go soft as you vomit on the way down. Don't try this at home. When I was a kid, I liked throwing zinc batteries on the bonfire to watch them explode - no such effect was ever observed. Even one single exhausted battery would have more zinc than a pretty big sheet of zinc plated steel - and would dwarf the amount of zinc vapourised by a weld run. Whenever you are working with galvanized steel it is important that you take the necessary steps when prepping the metal before welding. If you have properly prepped your metal before welding, you will help reduce your exposure to zinc oxide fumes. While prepping the base metal will remove the majority of the zinc from the surface of the metal, the possibility of some galvanizing while welding may occur. A common sign of galvanizing is the appearance of yellowish-green smoke. Other signs are a white powdery particles in the air, and a white residue around the weld. If exposure to large quantities of the yellowish-green zinc oxide fumes occur, you may experience galvanize poisoning, or metal fume fever as it is sometimes called. The severity of your symptoms depends on the amount of time of exposure to the harmful fumes. Galvanize Poisoning Symptoms of galvanize poisoning can be similar to flu symptoms. The onset of symptoms typically begin shortly after exposure to zinc oxide and may include a mild headache and nausea. If you have a more severe case of exposure, your symptoms will be consistent to those you experience when you have the flu. A moderate case of exposure will result in symptoms including chills, shaking, a slight fever, vomiting and cold sweats. If you begin to experience any of these symptoms you should immediately stop working and get some fresh air. In severe cases the symptoms may be so bad that you will have to go home until they subside. The most severe cases of galvanize poisoning can result in death. If you feel that your symptoms are worse than ever before, you should seek medical attention at once. Galvanize poisoning is often short and your symptoms should begin to lessen within four hours of exposure. You should be completely symptom free within twenty four hours. If you experience a stronger exposure, you may still be experiencing symptoms up to forty-eight hours later. We recommend upon exposure that you drink milk in order to quicken your recovery. The calcium in milk helps remove the zinc build-up from your body. AND Avoiding “Fume Fever” Feb 09, 2011 by bakersgas in Uncategorized Imagine you just finished up a day on the job, welding Galvanized Steel. You head home, shower up, and grab a beer as you settle in to watch the game on the tube. But then you start to feel kind of gross. Your legs start to ache, you become really thirsty with a blazing dry throat, and you start coughing and become congested, shivering all over. Things get worse from there as you spike a fever, feel nauseous and start throwing up. At the height of this two-day nightmare ride, you even hallucinate and experience convulsions. Is this the worse flu ever? Nope—you’ve just been hit by Fume Fever. It’s pretty nasty stuff, but totally preventable and fortunately, it’s not currently linked to any long-term health problems. Galvanized Steel is coated with a thin layer of zinc, and zinc melts at a much lower rate than steel, so when you’re welding Galvanized Steel, the zinc coating is vaporized and turns into zinc oxide. When you breath-in zinc oxide fumes, you develop what is commonly known as Fume Fever. This usually happens 1-4 hours after exposure and typically lasts for 1-2 days. The good news is these nasty side-effects are totally preventable. •Proper ventilation in your work area is the first, and most effective way to prevent the inhalation of zinc oxide fumes. Most shops and industrial complexes have effective ventilation and air filtration systems in-place, and outdoor job sites are generally not a problem, as fumes dissipate naturally outside. •If you’re working in a confined or unventilated work area, wear an approved respirator. Varying types of respirators are available, and the level of fumes you’re exposed to will dictate the type of respirator you need for a particular job. **Never eat, drink or smoke in an area contaminated by zinc oxide or any welding fumes. ***Always wash your hands thoroughly after you finish welding, and definitely before you eat—zinc oxide can be extremely poisonous if ingested |
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#42
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torque wrench issues
On Sun, 30 Apr 2017 21:22:36 -0400, Frank Krygowski
wrote: On 4/30/2017 5:27 PM, Ian Field wrote: Never heard of any warnings against welding zinc passivated steel - only know of cadmium plating being very dangerous. Fumes of burning zinc make your knees go soft as you vomit on the way down. Don't try this at home. When I was a kid, I liked throwing zinc batteries on the bonfire to watch them explode - no such effect was ever observed. Even one single exhausted battery would have more zinc than a pretty big sheet of zinc plated steel - and would dwarf the amount of zinc vapourised by a weld run. Well then, besides avoiding cad plate fasteners you ought to go straighten out the welding textbook industry. Having actually experienced the effect of burning zinc I sure won't do that again. YMMV. The imagination is a wonderous thing....................... True. It can make some people imagine maladies from touching cadmium plating. Let's just let Ian weld galvanized and find out the hard way. For the rest of you guys out there, take the warnibg to heart. Trust me - you won't live long enough to make all possible mistakes yourself (particularly if you do to many stupid things like welding galvanized without a good fume hood and repirator) |
#43
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torque wrench issues
On Sun, 30 Apr 2017 21:22:36 -0400, Frank Krygowski
wrote: On 4/30/2017 5:27 PM, Ian Field wrote: "AMuzi" wrote in message news On 4/30/2017 4:10 PM, Ian Field wrote: "AMuzi" wrote in message news On 4/30/2017 3:30 PM, Ian Field wrote: "AMuzi" wrote in message news On 4/30/2017 12:01 PM, Ian Field wrote: wrote in message ... On Sat, 29 Apr 2017 19:53:16 +0100, "Ian Field" wrote: wrote in message ... On Tue, 25 Apr 2017 20:16:22 +0100, "Benderthe.evilrobot" wrote: "John B Slocomb" wrote in message ... On Mon, 24 Apr 2017 22:17:14 -0400, wrote: On Tue, 25 Apr 2017 07:42:21 +0700, John B Slocomb wrote: On Mon, 24 Apr 2017 19:51:41 +0100, "Benderthe.evilrobot" wrote: wrote in message ... On Sun, 23 Apr 2017 22:06:05 +0100, "Benderthe.evilrobot" wrote: "Emanuel Berg" wrote in message ... I finally got the 1/2" torque wrench, 28-210 Nm, not even made in China, but in Taiwan! Eh... I guess it depends who you ask if that is China or not It has a locking screw, a torque setting handle, a scale (Nm as well as "FT-LB", some English unit I take it?) - it also as a locking lever on top just like an ordinary ratchet, so it can go both ways, clockwise and anti-clockwise. The torques only work in the clockwise direction. So if the locking (ratchet) lever is set the other way, it is just a ratchet, right? Well, in the manual it says: Note: Never use the torque wrench to undo nuts, bolts or other fasteners as this will damage the ratchet mechanism and the calibrated settings. So how does that add up? Is it only OK to use the anti-clockwise pull to insert things, which would require a left thread? (And it would be just a long shaft, with the torque not in effect.) As for me, I don't plan using it for anything but as a torque, because I have other, less expensive ratchets and spanners to do the everyday stuff. But of course, I'd like to know what it means. It also came with a certificate with data on the calibration and in the manual it says it should be recalibrated at least every 12 months. Calibration is irrelevant if you don't follow the rules to the letter. Most torque settings I've seen were for dry threads - any stray lubricant and you might even twist the end off at the correct torque. --- This email has been checked for viruses by AVG. http://www.avg.com Torque specs vary considerably by application. Some are given as clean and dry, some are given as lubricated with oil - some are given cold, and others hot. That said, I personally have never run across a torque spec that was so "close to the edge" that torqing with "stray lubrication" would cause immediate failure of the bolt by twisting off the end. However, that said, most of my wrenching has not been on bicycles but on automobiles and agricultural and construction equipment which may be slightly more "overengineered" or "overbuilt" Bicycles tend to have less things you can twist the end off. Its common on motorcycles, but mainly pulling the threads out of alloy castings. Its pretty rare to strip an engine down so far that you can put the castings in degreasing plant - torquing the engine case bolts with oil left in the holes is a very good chance of stripping the threads. As for stripping engine bolts, the Honda factory used to install fasteners so tight that a normal person couldn't get them out without an"impact driver". A tool that I never even saw before the Japanese invasion. The lock washers were very effective where used, and the Phipips style bolts were incapable of delivering enough torque to breat them loose without camming out - the Hammer Impact driver solved that problem I believe I've read that the "Phillips" headed screws in a Japanese motorcycle are not actually "Phillips" but some Japanese standard that didn't quite match the screwdrivers we had in the U.S. Which probably didn't help either :-) That's the *whole* cause - just grind a tiny bit off the point of the screwdriver bit and it fits just right. The bits on my Impact driver fit perfectly without grinding. Note I said Philips "style" (I know, I mis-spelled it) bolts. Some of the early Jap stuff didn't use Cadmium plated bolts either - W10 imploded and I had to start over with a replacement news account. So back to old name. The japs were the worst of the lot for cadmium plated fasteners. The very toxic cadmium rubs off on your hands and is cumulative in the body - it causes such acute osteoporosis; you can end up fracturing ribs just by coughing. In the UK - nickel plated fasteners became fashionable about the 80s. They didn't do much about cadmium plated chassis in electronic equipment until RoHS. AFAIK: cadmium batteries are exempt from RoHS - but they've more or less vanished from the shops anyway. Cadmium is very nasty - wash your hands after handling anything plated with it! from Cadmium, A Health Hazard Surface Treatment C. Rehm ESG Einsteinstr. 174 D-81675 Munich, Germany An object containing cadmium is not especially injurious to health on its own. No risk is involved simply by touching it. A potential hazard occurs, however, when such objects are processed and high temperatures are generated. Cadmium plating rubs off on your hands whenever you handle cadmium plated parts and assemblies. Many years ago they even used it on electronic component leads to prevent oxidation - they used more aggressive fluxes in those days. Welding cad plated sheet steel is particularly dangerous - the cadmium is vapourised and becomes airborne. Usually the osteoporosis takes decades to start crippling the sufferer - but I've heard of a repair technician dropping dead after a couple of years from fumes using low melting point cadmium based solder. The specific mode of death wasn't announced. The Japanese know all about it, they discharged industrial effluent containing cadmium into heavily fished costal waters. They even have a name for the disease - itai itai byo. apparently its the noise sufferers make in their death throes. As I mentioned previously - bones become so weak and brittle, you can fracture ribs just by coughing. Well then avoid it as you wish. Many of us recognize the difference between metals and reactive metallic organic compounds. Zinc rich tablets are popular for symptoms of herpes simplex and yet no one welds galvanize steel a second time. Zinc can't be that toxic - its a usual ingredient of baby powder. Never heard of any warnings against welding zinc passivated steel - only know of cadmium plating being very dangerous. Fumes of burning zinc make your knees go soft as you vomit on the way down. Don't try this at home. When I was a kid, I liked throwing zinc batteries on the bonfire to watch them explode - no such effect was ever observed. Even one single exhausted battery would have more zinc than a pretty big sheet of zinc plated steel - and would dwarf the amount of zinc vapourised by a weld run. Well then, besides avoiding cad plate fasteners you ought to go straighten out the welding textbook industry. Having actually experienced the effect of burning zinc I sure won't do that again. YMMV. The imagination is a wonderous thing....................... True. It can make some people imagine maladies from touching cadmium plating. Certainly Sir. After all a Styrofoam cover (with ventilation) for the head protects one from hurt so equally logically touching a cad plated bolt can prove disastrous. |
#45
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torque wrench issues
On Monday, May 1, 2017 at 1:08:39 AM UTC-7, John B Slocomb wrote:
On Sun, 30 Apr 2017 23:14:27 -0400, wrote: On Sun, 30 Apr 2017 22:10:43 +0100, "Ian Field" wrote: "AMuzi" wrote in message news On 4/30/2017 3:30 PM, Ian Field wrote: "AMuzi" wrote in message news On 4/30/2017 12:01 PM, Ian Field wrote: wrote in message ... On Sat, 29 Apr 2017 19:53:16 +0100, "Ian Field" wrote: wrote in message ... On Tue, 25 Apr 2017 20:16:22 +0100, "Benderthe.evilrobot" wrote: "John B Slocomb" wrote in message ... On Mon, 24 Apr 2017 22:17:14 -0400, wrote: On Tue, 25 Apr 2017 07:42:21 +0700, John B Slocomb wrote: On Mon, 24 Apr 2017 19:51:41 +0100, "Benderthe.evilrobot" wrote: wrote in message ... On Sun, 23 Apr 2017 22:06:05 +0100, "Benderthe.evilrobot" wrote: "Emanuel Berg" wrote in message ... I finally got the 1/2" torque wrench, 28-210 Nm, not even made in China, but in Taiwan! Eh... I guess it depends who you ask if that is China or not It has a locking screw, a torque setting handle, a scale (Nm as well as "FT-LB", some English unit I take it?) - it also as a locking lever on top just like an ordinary ratchet, so it can go both ways, clockwise and anti-clockwise. The torques only work in the clockwise direction. So if the locking (ratchet) lever is set the other way, it is just a ratchet, right? Well, in the manual it says: Note: Never use the torque wrench to undo nuts, bolts or other fasteners as this will damage the ratchet mechanism and the calibrated settings. So how does that add up? Is it only OK to use the anti-clockwise pull to insert things, which would require a left thread? (And it would be just a long shaft, with the torque not in effect.) As for me, I don't plan using it for anything but as a torque, because I have other, less expensive ratchets and spanners to do the everyday stuff. But of course, I'd like to know what it means. It also came with a certificate with data on the calibration and in the manual it says it should be recalibrated at least every 12 months. Calibration is irrelevant if you don't follow the rules to the letter. Most torque settings I've seen were for dry threads - any stray lubricant and you might even twist the end off at the correct torque. --- This email has been checked for viruses by AVG. http://www.avg.com Torque specs vary considerably by application. Some are given as clean and dry, some are given as lubricated with oil - some are given cold, and others hot. That said, I personally have never run across a torque spec that was so "close to the edge" that torqing with "stray lubrication" would cause immediate failure of the bolt by twisting off the end. However, that said, most of my wrenching has not been on bicycles but on automobiles and agricultural and construction equipment which may be slightly more "overengineered" or "overbuilt" Bicycles tend to have less things you can twist the end off. Its common on motorcycles, but mainly pulling the threads out of alloy castings. Its pretty rare to strip an engine down so far that you can put the castings in degreasing plant - torquing the engine case bolts with oil left in the holes is a very good chance of stripping the threads. As for stripping engine bolts, the Honda factory used to install fasteners so tight that a normal person couldn't get them out without an"impact driver". A tool that I never even saw before the Japanese invasion. The lock washers were very effective where used, and the Phipips style bolts were incapable of delivering enough torque to breat them loose without camming out - the Hammer Impact driver solved that problem I believe I've read that the "Phillips" headed screws in a Japanese motorcycle are not actually "Phillips" but some Japanese standard that didn't quite match the screwdrivers we had in the U.S. Which probably didn't help either :-) That's the *whole* cause - just grind a tiny bit off the point of the screwdriver bit and it fits just right. The bits on my Impact driver fit perfectly without grinding. Note I said Philips "style" (I know, I mis-spelled it) bolts. Some of the early Jap stuff didn't use Cadmium plated bolts either - W10 imploded and I had to start over with a replacement news account. So back to old name. The japs were the worst of the lot for cadmium plated fasteners. The very toxic cadmium rubs off on your hands and is cumulative in the body - it causes such acute osteoporosis; you can end up fracturing ribs just by coughing. In the UK - nickel plated fasteners became fashionable about the 80s. They didn't do much about cadmium plated chassis in electronic equipment until RoHS. AFAIK: cadmium batteries are exempt from RoHS - but they've more or less vanished from the shops anyway. Cadmium is very nasty - wash your hands after handling anything plated with it! from Cadmium, A Health Hazard Surface Treatment C. Rehm ESG Einsteinstr. 174 D-81675 Munich, Germany An object containing cadmium is not especially injurious to health on its own. No risk is involved simply by touching it. A potential hazard occurs, however, when such objects are processed and high temperatures are generated. Cadmium plating rubs off on your hands whenever you handle cadmium plated parts and assemblies. Many years ago they even used it on electronic component leads to prevent oxidation - they used more aggressive fluxes in those days. Welding cad plated sheet steel is particularly dangerous - the cadmium is vapourised and becomes airborne. Usually the osteoporosis takes decades to start crippling the sufferer - but I've heard of a repair technician dropping dead after a couple of years from fumes using low melting point cadmium based solder. The specific mode of death wasn't announced. The Japanese know all about it, they discharged industrial effluent containing cadmium into heavily fished costal waters. They even have a name for the disease - itai itai byo. apparently its the noise sufferers make in their death throes. As I mentioned previously - bones become so weak and brittle, you can fracture ribs just by coughing. Well then avoid it as you wish. Many of us recognize the difference between metals and reactive metallic organic compounds. Zinc rich tablets are popular for symptoms of herpes simplex and yet no one welds galvanize steel a second time. Zinc can't be that toxic - its a usual ingredient of baby powder. Never heard of any warnings against welding zinc passivated steel - only know of cadmium plating being very dangerous. Fumes of burning zinc make your knees go soft as you vomit on the way down. Don't try this at home. When I was a kid, I liked throwing zinc batteries on the bonfire to watch them explode - no such effect was ever observed. Even one single exhausted battery would have more zinc than a pretty big sheet of zinc plated steel - and would dwarf the amount of zinc vapourised by a weld run. Whenever you are working with galvanized steel it is important that you take the necessary steps when prepping the metal before welding. If you have properly prepped your metal before welding, you will help reduce your exposure to zinc oxide fumes. The usually suggested preparation for welding or brazing galvanized materials is to grind all the galvanizing off! Welding a joint with zinc still on the area would weaken the weld but who am I to suggest that you're right? Smokers have very high amounts of cadmium in their bodies. If you've smoked for 50 years you probably have the maximum allowable amount of cadmium in your body. You can get cadmium in your body by touching it. The amount into your plasma is as high as 0.07%. The half-life of cadmium in the body is about 10 years if memory serves. But both zinc and cadmium would normally only accumulate to dangerous levels at a rate that wouldn't harm you until long after you're dead unless you're a smoker. |
#46
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torque wrench issues
"Frank Krygowski" wrote in message news On 4/30/2017 5:27 PM, Ian Field wrote: "AMuzi" wrote in message news On 4/30/2017 4:10 PM, Ian Field wrote: "AMuzi" wrote in message news On 4/30/2017 3:30 PM, Ian Field wrote: "AMuzi" wrote in message news On 4/30/2017 12:01 PM, Ian Field wrote: wrote in message ... On Sat, 29 Apr 2017 19:53:16 +0100, "Ian Field" wrote: wrote in message ... On Tue, 25 Apr 2017 20:16:22 +0100, "Benderthe.evilrobot" wrote: "John B Slocomb" wrote in message ... On Mon, 24 Apr 2017 22:17:14 -0400, wrote: On Tue, 25 Apr 2017 07:42:21 +0700, John B Slocomb wrote: On Mon, 24 Apr 2017 19:51:41 +0100, "Benderthe.evilrobot" wrote: wrote in message ... On Sun, 23 Apr 2017 22:06:05 +0100, "Benderthe.evilrobot" wrote: "Emanuel Berg" wrote in message ... I finally got the 1/2" torque wrench, 28-210 Nm, not even made in China, but in Taiwan! Eh... I guess it depends who you ask if that is China or not It has a locking screw, a torque setting handle, a scale (Nm as well as "FT-LB", some English unit I take it?) - it also as a locking lever on top just like an ordinary ratchet, so it can go both ways, clockwise and anti-clockwise. The torques only work in the clockwise direction. So if the locking (ratchet) lever is set the other way, it is just a ratchet, right? Well, in the manual it says: Note: Never use the torque wrench to undo nuts, bolts or other fasteners as this will damage the ratchet mechanism and the calibrated settings. So how does that add up? Is it only OK to use the anti-clockwise pull to insert things, which would require a left thread? (And it would be just a long shaft, with the torque not in effect.) As for me, I don't plan using it for anything but as a torque, because I have other, less expensive ratchets and spanners to do the everyday stuff. But of course, I'd like to know what it means. It also came with a certificate with data on the calibration and in the manual it says it should be recalibrated at least every 12 months. Calibration is irrelevant if you don't follow the rules to the letter. Most torque settings I've seen were for dry threads - any stray lubricant and you might even twist the end off at the correct torque. --- This email has been checked for viruses by AVG. http://www.avg.com Torque specs vary considerably by application. Some are given as clean and dry, some are given as lubricated with oil - some are given cold, and others hot. That said, I personally have never run across a torque spec that was so "close to the edge" that torqing with "stray lubrication" would cause immediate failure of the bolt by twisting off the end. However, that said, most of my wrenching has not been on bicycles but on automobiles and agricultural and construction equipment which may be slightly more "overengineered" or "overbuilt" Bicycles tend to have less things you can twist the end off. Its common on motorcycles, but mainly pulling the threads out of alloy castings. Its pretty rare to strip an engine down so far that you can put the castings in degreasing plant - torquing the engine case bolts with oil left in the holes is a very good chance of stripping the threads. As for stripping engine bolts, the Honda factory used to install fasteners so tight that a normal person couldn't get them out without an"impact driver". A tool that I never even saw before the Japanese invasion. The lock washers were very effective where used, and the Phipips style bolts were incapable of delivering enough torque to breat them loose without camming out - the Hammer Impact driver solved that problem I believe I've read that the "Phillips" headed screws in a Japanese motorcycle are not actually "Phillips" but some Japanese standard that didn't quite match the screwdrivers we had in the U.S. Which probably didn't help either :-) That's the *whole* cause - just grind a tiny bit off the point of the screwdriver bit and it fits just right. The bits on my Impact driver fit perfectly without grinding. Note I said Philips "style" (I know, I mis-spelled it) bolts. Some of the early Jap stuff didn't use Cadmium plated bolts either - W10 imploded and I had to start over with a replacement news account. So back to old name. The japs were the worst of the lot for cadmium plated fasteners. The very toxic cadmium rubs off on your hands and is cumulative in the body - it causes such acute osteoporosis; you can end up fracturing ribs just by coughing. In the UK - nickel plated fasteners became fashionable about the 80s. They didn't do much about cadmium plated chassis in electronic equipment until RoHS. AFAIK: cadmium batteries are exempt from RoHS - but they've more or less vanished from the shops anyway. Cadmium is very nasty - wash your hands after handling anything plated with it! from Cadmium, A Health Hazard Surface Treatment C. Rehm ESG Einsteinstr. 174 D-81675 Munich, Germany An object containing cadmium is not especially injurious to health on its own. No risk is involved simply by touching it. A potential hazard occurs, however, when such objects are processed and high temperatures are generated. Cadmium plating rubs off on your hands whenever you handle cadmium plated parts and assemblies. Many years ago they even used it on electronic component leads to prevent oxidation - they used more aggressive fluxes in those days. Welding cad plated sheet steel is particularly dangerous - the cadmium is vapourised and becomes airborne. Usually the osteoporosis takes decades to start crippling the sufferer - but I've heard of a repair technician dropping dead after a couple of years from fumes using low melting point cadmium based solder. The specific mode of death wasn't announced. The Japanese know all about it, they discharged industrial effluent containing cadmium into heavily fished costal waters. They even have a name for the disease - itai itai byo. apparently its the noise sufferers make in their death throes. As I mentioned previously - bones become so weak and brittle, you can fracture ribs just by coughing. Well then avoid it as you wish. Many of us recognize the difference between metals and reactive metallic organic compounds. Zinc rich tablets are popular for symptoms of herpes simplex and yet no one welds galvanize steel a second time. Zinc can't be that toxic - its a usual ingredient of baby powder. Never heard of any warnings against welding zinc passivated steel - only know of cadmium plating being very dangerous. Fumes of burning zinc make your knees go soft as you vomit on the way down. Don't try this at home. When I was a kid, I liked throwing zinc batteries on the bonfire to watch them explode - no such effect was ever observed. Even one single exhausted battery would have more zinc than a pretty big sheet of zinc plated steel - and would dwarf the amount of zinc vapourised by a weld run. Well then, besides avoiding cad plate fasteners you ought to go straighten out the welding textbook industry. Having actually experienced the effect of burning zinc I sure won't do that again. YMMV. The imagination is a wonderous thing....................... True. It can make some people imagine maladies from touching cadmium plating. Fine - carry on being careless with toxic heavy metals. You might even live longer than me - but you'll wish you hadn't! |
#47
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torque wrench issues
wrote in message ... On Sun, 30 Apr 2017 21:22:36 -0400, Frank Krygowski wrote: On 4/30/2017 5:27 PM, Ian Field wrote: Never heard of any warnings against welding zinc passivated steel - only know of cadmium plating being very dangerous. Fumes of burning zinc make your knees go soft as you vomit on the way down. Don't try this at home. When I was a kid, I liked throwing zinc batteries on the bonfire to watch them explode - no such effect was ever observed. Even one single exhausted battery would have more zinc than a pretty big sheet of zinc plated steel - and would dwarf the amount of zinc vapourised by a weld run. Well then, besides avoiding cad plate fasteners you ought to go straighten out the welding textbook industry. Having actually experienced the effect of burning zinc I sure won't do that again. YMMV. The imagination is a wonderous thing....................... True. It can make some people imagine maladies from touching cadmium plating. Let's just let Ian weld galvanized and find out the hard way. For the rest of you guys out there, take the warnibg to heart. Trust me - you won't live long enough to make all possible mistakes yourself (particularly if you do to many stupid things like welding galvanized without a good fume hood and repirator) I have welded galvanised - and nothing bad happened. Zinc is a component of baby powder and most winter defense vitamin supplements. There may be enough zinc in a battery for a toxic dose - but no one seems to be taking much notice. When you weld cadmiumn plated - there's no immediate ill effects. That happens years later when your bones start to crumble. Cadmium poisoning is cummulative and there's no safe way of removing it. Sometimes Darwin takes his own sweet time removing ****wits from the gene pool. |
#48
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torque wrench issues
"John B Slocomb" wrote in message ... On Sun, 30 Apr 2017 21:22:36 -0400, Frank Krygowski wrote: On 4/30/2017 5:27 PM, Ian Field wrote: "AMuzi" wrote in message news On 4/30/2017 4:10 PM, Ian Field wrote: "AMuzi" wrote in message news On 4/30/2017 3:30 PM, Ian Field wrote: "AMuzi" wrote in message news On 4/30/2017 12:01 PM, Ian Field wrote: wrote in message ... On Sat, 29 Apr 2017 19:53:16 +0100, "Ian Field" wrote: wrote in message ... On Tue, 25 Apr 2017 20:16:22 +0100, "Benderthe.evilrobot" wrote: "John B Slocomb" wrote in message ... On Mon, 24 Apr 2017 22:17:14 -0400, wrote: On Tue, 25 Apr 2017 07:42:21 +0700, John B Slocomb wrote: On Mon, 24 Apr 2017 19:51:41 +0100, "Benderthe.evilrobot" wrote: wrote in message ... On Sun, 23 Apr 2017 22:06:05 +0100, "Benderthe.evilrobot" wrote: "Emanuel Berg" wrote in message ... I finally got the 1/2" torque wrench, 28-210 Nm, not even made in China, but in Taiwan! Eh... I guess it depends who you ask if that is China or not It has a locking screw, a torque setting handle, a scale (Nm as well as "FT-LB", some English unit I take it?) - it also as a locking lever on top just like an ordinary ratchet, so it can go both ways, clockwise and anti-clockwise. The torques only work in the clockwise direction. So if the locking (ratchet) lever is set the other way, it is just a ratchet, right? Well, in the manual it says: Note: Never use the torque wrench to undo nuts, bolts or other fasteners as this will damage the ratchet mechanism and the calibrated settings. So how does that add up? Is it only OK to use the anti-clockwise pull to insert things, which would require a left thread? (And it would be just a long shaft, with the torque not in effect.) As for me, I don't plan using it for anything but as a torque, because I have other, less expensive ratchets and spanners to do the everyday stuff. But of course, I'd like to know what it means. It also came with a certificate with data on the calibration and in the manual it says it should be recalibrated at least every 12 months. Calibration is irrelevant if you don't follow the rules to the letter. Most torque settings I've seen were for dry threads - any stray lubricant and you might even twist the end off at the correct torque. --- This email has been checked for viruses by AVG. http://www.avg.com Torque specs vary considerably by application. Some are given as clean and dry, some are given as lubricated with oil - some are given cold, and others hot. That said, I personally have never run across a torque spec that was so "close to the edge" that torqing with "stray lubrication" would cause immediate failure of the bolt by twisting off the end. However, that said, most of my wrenching has not been on bicycles but on automobiles and agricultural and construction equipment which may be slightly more "overengineered" or "overbuilt" Bicycles tend to have less things you can twist the end off. Its common on motorcycles, but mainly pulling the threads out of alloy castings. Its pretty rare to strip an engine down so far that you can put the castings in degreasing plant - torquing the engine case bolts with oil left in the holes is a very good chance of stripping the threads. As for stripping engine bolts, the Honda factory used to install fasteners so tight that a normal person couldn't get them out without an"impact driver". A tool that I never even saw before the Japanese invasion. The lock washers were very effective where used, and the Phipips style bolts were incapable of delivering enough torque to breat them loose without camming out - the Hammer Impact driver solved that problem I believe I've read that the "Phillips" headed screws in a Japanese motorcycle are not actually "Phillips" but some Japanese standard that didn't quite match the screwdrivers we had in the U.S. Which probably didn't help either :-) That's the *whole* cause - just grind a tiny bit off the point of the screwdriver bit and it fits just right. The bits on my Impact driver fit perfectly without grinding. Note I said Philips "style" (I know, I mis-spelled it) bolts. Some of the early Jap stuff didn't use Cadmium plated bolts either - W10 imploded and I had to start over with a replacement news account. So back to old name. The japs were the worst of the lot for cadmium plated fasteners. The very toxic cadmium rubs off on your hands and is cumulative in the body - it causes such acute osteoporosis; you can end up fracturing ribs just by coughing. In the UK - nickel plated fasteners became fashionable about the 80s. They didn't do much about cadmium plated chassis in electronic equipment until RoHS. AFAIK: cadmium batteries are exempt from RoHS - but they've more or less vanished from the shops anyway. Cadmium is very nasty - wash your hands after handling anything plated with it! from Cadmium, A Health Hazard Surface Treatment C. Rehm ESG Einsteinstr. 174 D-81675 Munich, Germany An object containing cadmium is not especially injurious to health on its own. No risk is involved simply by touching it. A potential hazard occurs, however, when such objects are processed and high temperatures are generated. Cadmium plating rubs off on your hands whenever you handle cadmium plated parts and assemblies. Many years ago they even used it on electronic component leads to prevent oxidation - they used more aggressive fluxes in those days. Welding cad plated sheet steel is particularly dangerous - the cadmium is vapourised and becomes airborne. Usually the osteoporosis takes decades to start crippling the sufferer - but I've heard of a repair technician dropping dead after a couple of years from fumes using low melting point cadmium based solder. The specific mode of death wasn't announced. The Japanese know all about it, they discharged industrial effluent containing cadmium into heavily fished costal waters. They even have a name for the disease - itai itai byo. apparently its the noise sufferers make in their death throes. As I mentioned previously - bones become so weak and brittle, you can fracture ribs just by coughing. Well then avoid it as you wish. Many of us recognize the difference between metals and reactive metallic organic compounds. Zinc rich tablets are popular for symptoms of herpes simplex and yet no one welds galvanize steel a second time. Zinc can't be that toxic - its a usual ingredient of baby powder. Never heard of any warnings against welding zinc passivated steel - only know of cadmium plating being very dangerous. Fumes of burning zinc make your knees go soft as you vomit on the way down. Don't try this at home. When I was a kid, I liked throwing zinc batteries on the bonfire to watch them explode - no such effect was ever observed. Even one single exhausted battery would have more zinc than a pretty big sheet of zinc plated steel - and would dwarf the amount of zinc vapourised by a weld run. Well then, besides avoiding cad plate fasteners you ought to go straighten out the welding textbook industry. Having actually experienced the effect of burning zinc I sure won't do that again. YMMV. The imagination is a wonderous thing....................... True. It can make some people imagine maladies from touching cadmium plating. Certainly Sir. After all a Styrofoam cover (with ventilation) for the head protects one from hurt so equally logically touching a cad plated bolt can prove disastrous. This NG is a gene pool that needs all the cadmium it can get............................... |
#49
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torque wrench issues
"John B Slocomb" wrote in message ... On Sun, 30 Apr 2017 23:14:27 -0400, wrote: On Sun, 30 Apr 2017 22:10:43 +0100, "Ian Field" wrote: "AMuzi" wrote in message news On 4/30/2017 3:30 PM, Ian Field wrote: "AMuzi" wrote in message news On 4/30/2017 12:01 PM, Ian Field wrote: wrote in message ... On Sat, 29 Apr 2017 19:53:16 +0100, "Ian Field" wrote: wrote in message ... On Tue, 25 Apr 2017 20:16:22 +0100, "Benderthe.evilrobot" wrote: "John B Slocomb" wrote in message ... On Mon, 24 Apr 2017 22:17:14 -0400, wrote: On Tue, 25 Apr 2017 07:42:21 +0700, John B Slocomb wrote: On Mon, 24 Apr 2017 19:51:41 +0100, "Benderthe.evilrobot" wrote: wrote in message ... On Sun, 23 Apr 2017 22:06:05 +0100, "Benderthe.evilrobot" wrote: "Emanuel Berg" wrote in message ... I finally got the 1/2" torque wrench, 28-210 Nm, not even made in China, but in Taiwan! Eh... I guess it depends who you ask if that is China or not It has a locking screw, a torque setting handle, a scale (Nm as well as "FT-LB", some English unit I take it?) - it also as a locking lever on top just like an ordinary ratchet, so it can go both ways, clockwise and anti-clockwise. The torques only work in the clockwise direction. So if the locking (ratchet) lever is set the other way, it is just a ratchet, right? Well, in the manual it says: Note: Never use the torque wrench to undo nuts, bolts or other fasteners as this will damage the ratchet mechanism and the calibrated settings. So how does that add up? Is it only OK to use the anti-clockwise pull to insert things, which would require a left thread? (And it would be just a long shaft, with the torque not in effect.) As for me, I don't plan using it for anything but as a torque, because I have other, less expensive ratchets and spanners to do the everyday stuff. But of course, I'd like to know what it means. It also came with a certificate with data on the calibration and in the manual it says it should be recalibrated at least every 12 months. Calibration is irrelevant if you don't follow the rules to the letter. Most torque settings I've seen were for dry threads - any stray lubricant and you might even twist the end off at the correct torque. --- This email has been checked for viruses by AVG. http://www.avg.com Torque specs vary considerably by application. Some are given as clean and dry, some are given as lubricated with oil - some are given cold, and others hot. That said, I personally have never run across a torque spec that was so "close to the edge" that torqing with "stray lubrication" would cause immediate failure of the bolt by twisting off the end. However, that said, most of my wrenching has not been on bicycles but on automobiles and agricultural and construction equipment which may be slightly more "overengineered" or "overbuilt" Bicycles tend to have less things you can twist the end off. Its common on motorcycles, but mainly pulling the threads out of alloy castings. Its pretty rare to strip an engine down so far that you can put the castings in degreasing plant - torquing the engine case bolts with oil left in the holes is a very good chance of stripping the threads. As for stripping engine bolts, the Honda factory used to install fasteners so tight that a normal person couldn't get them out without an"impact driver". A tool that I never even saw before the Japanese invasion. The lock washers were very effective where used, and the Phipips style bolts were incapable of delivering enough torque to breat them loose without camming out - the Hammer Impact driver solved that problem I believe I've read that the "Phillips" headed screws in a Japanese motorcycle are not actually "Phillips" but some Japanese standard that didn't quite match the screwdrivers we had in the U.S. Which probably didn't help either :-) That's the *whole* cause - just grind a tiny bit off the point of the screwdriver bit and it fits just right. The bits on my Impact driver fit perfectly without grinding. Note I said Philips "style" (I know, I mis-spelled it) bolts. Some of the early Jap stuff didn't use Cadmium plated bolts either - W10 imploded and I had to start over with a replacement news account. So back to old name. The japs were the worst of the lot for cadmium plated fasteners. The very toxic cadmium rubs off on your hands and is cumulative in the body - it causes such acute osteoporosis; you can end up fracturing ribs just by coughing. In the UK - nickel plated fasteners became fashionable about the 80s. They didn't do much about cadmium plated chassis in electronic equipment until RoHS. AFAIK: cadmium batteries are exempt from RoHS - but they've more or less vanished from the shops anyway. Cadmium is very nasty - wash your hands after handling anything plated with it! from Cadmium, A Health Hazard Surface Treatment C. Rehm ESG Einsteinstr. 174 D-81675 Munich, Germany An object containing cadmium is not especially injurious to health on its own. No risk is involved simply by touching it. A potential hazard occurs, however, when such objects are processed and high temperatures are generated. Cadmium plating rubs off on your hands whenever you handle cadmium plated parts and assemblies. Many years ago they even used it on electronic component leads to prevent oxidation - they used more aggressive fluxes in those days. Welding cad plated sheet steel is particularly dangerous - the cadmium is vapourised and becomes airborne. Usually the osteoporosis takes decades to start crippling the sufferer - but I've heard of a repair technician dropping dead after a couple of years from fumes using low melting point cadmium based solder. The specific mode of death wasn't announced. The Japanese know all about it, they discharged industrial effluent containing cadmium into heavily fished costal waters. They even have a name for the disease - itai itai byo. apparently its the noise sufferers make in their death throes. As I mentioned previously - bones become so weak and brittle, you can fracture ribs just by coughing. Well then avoid it as you wish. Many of us recognize the difference between metals and reactive metallic organic compounds. Zinc rich tablets are popular for symptoms of herpes simplex and yet no one welds galvanize steel a second time. Zinc can't be that toxic - its a usual ingredient of baby powder. Never heard of any warnings against welding zinc passivated steel - only know of cadmium plating being very dangerous. Fumes of burning zinc make your knees go soft as you vomit on the way down. Don't try this at home. When I was a kid, I liked throwing zinc batteries on the bonfire to watch them explode - no such effect was ever observed. Even one single exhausted battery would have more zinc than a pretty big sheet of zinc plated steel - and would dwarf the amount of zinc vapourised by a weld run. Whenever you are working with galvanized steel it is important that you take the necessary steps when prepping the metal before welding. If you have properly prepped your metal before welding, you will help reduce your exposure to zinc oxide fumes. The usually suggested preparation for welding or brazing galvanized materials is to grind all the galvanizing off! Genius!!! - you've invented a way to breathe it as dust instead of fumes. Darwin must be biding his time with you............................... |
#50
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torque wrench issues
wrote in message ... On Monday, May 1, 2017 at 1:08:39 AM UTC-7, John B Slocomb wrote: On Sun, 30 Apr 2017 23:14:27 -0400, wrote: On Sun, 30 Apr 2017 22:10:43 +0100, "Ian Field" wrote: "AMuzi" wrote in message news On 4/30/2017 3:30 PM, Ian Field wrote: "AMuzi" wrote in message news On 4/30/2017 12:01 PM, Ian Field wrote: wrote in message ... On Sat, 29 Apr 2017 19:53:16 +0100, "Ian Field" wrote: wrote in message ... On Tue, 25 Apr 2017 20:16:22 +0100, "Benderthe.evilrobot" wrote: "John B Slocomb" wrote in message ... On Mon, 24 Apr 2017 22:17:14 -0400, wrote: On Tue, 25 Apr 2017 07:42:21 +0700, John B Slocomb wrote: On Mon, 24 Apr 2017 19:51:41 +0100, "Benderthe.evilrobot" wrote: wrote in message ... On Sun, 23 Apr 2017 22:06:05 +0100, "Benderthe.evilrobot" wrote: "Emanuel Berg" wrote in message ... I finally got the 1/2" torque wrench, 28-210 Nm, not even made in China, but in Taiwan! Eh... I guess it depends who you ask if that is China or not It has a locking screw, a torque setting handle, a scale (Nm as well as "FT-LB", some English unit I take it?) - it also as a locking lever on top just like an ordinary ratchet, so it can go both ways, clockwise and anti-clockwise. The torques only work in the clockwise direction. So if the locking (ratchet) lever is set the other way, it is just a ratchet, right? Well, in the manual it says: Note: Never use the torque wrench to undo nuts, bolts or other fasteners as this will damage the ratchet mechanism and the calibrated settings. So how does that add up? Is it only OK to use the anti-clockwise pull to insert things, which would require a left thread? (And it would be just a long shaft, with the torque not in effect.) As for me, I don't plan using it for anything but as a torque, because I have other, less expensive ratchets and spanners to do the everyday stuff. But of course, I'd like to know what it means. It also came with a certificate with data on the calibration and in the manual it says it should be recalibrated at least every 12 months. Calibration is irrelevant if you don't follow the rules to the letter. Most torque settings I've seen were for dry threads - any stray lubricant and you might even twist the end off at the correct torque. --- This email has been checked for viruses by AVG. http://www.avg.com Torque specs vary considerably by application. Some are given as clean and dry, some are given as lubricated with oil - some are given cold, and others hot. That said, I personally have never run across a torque spec that was so "close to the edge" that torqing with "stray lubrication" would cause immediate failure of the bolt by twisting off the end. However, that said, most of my wrenching has not been on bicycles but on automobiles and agricultural and construction equipment which may be slightly more "overengineered" or "overbuilt" Bicycles tend to have less things you can twist the end off. Its common on motorcycles, but mainly pulling the threads out of alloy castings. Its pretty rare to strip an engine down so far that you can put the castings in degreasing plant - torquing the engine case bolts with oil left in the holes is a very good chance of stripping the threads. As for stripping engine bolts, the Honda factory used to install fasteners so tight that a normal person couldn't get them out without an"impact driver". A tool that I never even saw before the Japanese invasion. The lock washers were very effective where used, and the Phipips style bolts were incapable of delivering enough torque to breat them loose without camming out - the Hammer Impact driver solved that problem I believe I've read that the "Phillips" headed screws in a Japanese motorcycle are not actually "Phillips" but some Japanese standard that didn't quite match the screwdrivers we had in the U.S. Which probably didn't help either :-) That's the *whole* cause - just grind a tiny bit off the point of the screwdriver bit and it fits just right. The bits on my Impact driver fit perfectly without grinding. Note I said Philips "style" (I know, I mis-spelled it) bolts. Some of the early Jap stuff didn't use Cadmium plated bolts either - W10 imploded and I had to start over with a replacement news account. So back to old name. The japs were the worst of the lot for cadmium plated fasteners. The very toxic cadmium rubs off on your hands and is cumulative in the body - it causes such acute osteoporosis; you can end up fracturing ribs just by coughing. In the UK - nickel plated fasteners became fashionable about the 80s. They didn't do much about cadmium plated chassis in electronic equipment until RoHS. AFAIK: cadmium batteries are exempt from RoHS - but they've more or less vanished from the shops anyway. Cadmium is very nasty - wash your hands after handling anything plated with it! from Cadmium, A Health Hazard Surface Treatment C. Rehm ESG Einsteinstr. 174 D-81675 Munich, Germany An object containing cadmium is not especially injurious to health on its own. No risk is involved simply by touching it. A potential hazard occurs, however, when such objects are processed and high temperatures are generated. Cadmium plating rubs off on your hands whenever you handle cadmium plated parts and assemblies. Many years ago they even used it on electronic component leads to prevent oxidation - they used more aggressive fluxes in those days. Welding cad plated sheet steel is particularly dangerous - the cadmium is vapourised and becomes airborne. Usually the osteoporosis takes decades to start crippling the sufferer - but I've heard of a repair technician dropping dead after a couple of years from fumes using low melting point cadmium based solder. The specific mode of death wasn't announced. The Japanese know all about it, they discharged industrial effluent containing cadmium into heavily fished costal waters. They even have a name for the disease - itai itai byo. apparently its the noise sufferers make in their death throes. As I mentioned previously - bones become so weak and brittle, you can fracture ribs just by coughing. Well then avoid it as you wish. Many of us recognize the difference between metals and reactive metallic organic compounds. Zinc rich tablets are popular for symptoms of herpes simplex and yet no one welds galvanize steel a second time. Zinc can't be that toxic - its a usual ingredient of baby powder. Never heard of any warnings against welding zinc passivated steel - only know of cadmium plating being very dangerous. Fumes of burning zinc make your knees go soft as you vomit on the way down. Don't try this at home. When I was a kid, I liked throwing zinc batteries on the bonfire to watch them explode - no such effect was ever observed. Even one single exhausted battery would have more zinc than a pretty big sheet of zinc plated steel - and would dwarf the amount of zinc vapourised by a weld run. Whenever you are working with galvanized steel it is important that you take the necessary steps when prepping the metal before welding. If you have properly prepped your metal before welding, you will help reduce your exposure to zinc oxide fumes. The usually suggested preparation for welding or brazing galvanized materials is to grind all the galvanizing off! Welding a joint with zinc still on the area would weaken the weld but who am I to suggest that you're right? Smokers have very high amounts of cadmium in their bodies. If you've smoked for 50 years you probably have the maximum allowable amount of cadmium in your body. You can get cadmium in your body by touching it. The amount into your plasma is as high as 0.07%. The half-life of cadmium in the body is about 10 years if memory serves. But both zinc and cadmium would normally only accumulate to dangerous levels at a rate that wouldn't harm you until long after you're dead unless you're a smoker. The people who made the RoHS list don't seem very keen on cadmium - like most battery systems; the cadmium ones got an exemption. However - most battery manufacturers seem to have voluntarily dropped cadmium. You can still get them for specialist applications like security systems, but general types have pretty much vanished from the shops. I'm not aware of any restrictions on zinc - zinc/air hearing aid batteries have if anything, increased in popularity. Because they need air to work - they're not fully sealed. |
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