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#82
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torque wrench issues
"John B Slocomb" wrote in message ... On Tue, 02 May 2017 08:31:47 +0700, John B Slocomb wrote: On Mon, 1 May 2017 21:14:22 +0100, "Ian Field" wrote: wrote in message ... On Mon, 1 May 2017 07:06:39 -0700 (PDT), wrote: 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. Or a careless welder. Brazing spelter containing cadmium can make you sicker than a dog in short order if you are breathing the fumes - as can the fumes from welding galvanized steel. It only takes a few minutes to get you wretching and puking and aching to the point you almost wish you could die. "galvanised" is galvanic protection - which can include any of several toxic heavy metals. While yes, galvanizing is a galvanic protection if you go into a store and ask for "galvanized iron" you get zinc coated steel. As an addendum. I am not sure that galvanizing is necessarily a galvanic protection. I an thinking of the corrugated "galvanized iron" roofs I see on wooden buildings here. Unless, of course, there is some sort of galvanic action between wooden rafters and steel sheeting :-) The steel has impurities which produce galvanic differences across a surface area - add water (especially acid rain) and galvanic action produces electrolysis. You're probably so dumb that explaining it didn't help much.................. |
#83
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torque wrench issues
"AMuzi" wrote in message news On 5/2/2017 4:31 AM, John B Slocomb wrote: On Tue, 02 May 2017 08:31:47 +0700, John B Slocomb wrote: On Mon, 1 May 2017 21:14:22 +0100, "Ian Field" wrote: wrote in message ... On Mon, 1 May 2017 07:06:39 -0700 (PDT), wrote: 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. Or a careless welder. Brazing spelter containing cadmium can make you sicker than a dog in short order if you are breathing the fumes - as can the fumes from welding galvanized steel. It only takes a few minutes to get you wretching and puking and aching to the point you almost wish you could die. "galvanised" is galvanic protection - which can include any of several toxic heavy metals. While yes, galvanizing is a galvanic protection if you go into a store and ask for "galvanized iron" you get zinc coated steel. As an addendum. I am not sure that galvanizing is necessarily a galvanic protection. I an thinking of the corrugated "galvanized iron" roofs I see on wooden buildings here. Unless, of course, there is some sort of galvanic action between wooden rafters and steel sheeting :-) Some people here seem to think it can only mean zinc. No, "galvanized", in common U.S. usage, does mean zinc coated. The toxic dose of zinc is really quite large. Galvanized steel has a sacrificial zinc layer with more potential than the steel. Well at least you got that bit right - but zinc isn't the only plating metal that does that. |
#84
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torque wrench issues
wrote in message ... On Mon, 1 May 2017 22:12:57 +0100, "Ian Field" wrote: "AMuzi" wrote in message news On 5/1/2017 2:35 PM, wrote: "Ian Field" wrote: "John B Slocomb" wrote wrote: "Ian Field" wrote: "AMuzi" wrote On 4/30/2017 3:30 PM, Ian Field wrote: "AMuzi" wrote On 4/30/2017 12:01 PM, Ian Field wrote: wrote "Ian Field" wrote: wrote "Benderthe.evilrobot" wrote: "John B Slocomb" wrote wrote: John B Slocomb wrote: "Benderthe.evilrobot" wrote: wrote "Benderthe.evilrobot" wrote: "Emanuel Berg" wrote -snip much speculation about organic chemistry- Metallic zinc is not anywhere near as dangerous as the zinc oxide fumes from over-heated zinc - justlike contact with cadmium metal itself is "relatively" benign - and touching chrome plated metal is not dangerous, yet co-valent Chromium is highly toxic. Same with mercury - although mercury vapour definitely is not GOOD for you, it is the "organic compounds" of mercury that are particularly dangerous and insidious. +1 Which is saying something...........................AFAIK: zinc oxide isn't particularly dangerous either. Some sellers of CPU heat transfer paste pass off zinc oxide as high tech ceramic filler and charge a lot more money. Its a bit of a grey area - but I think it more or less is a form of ceramic. The *REALLY* toxic oxide is beryllium. That also is used for thermal transfer - RoHS exempted some toxic materials because the impact on industry would be too severe, beryllium was one of them. Give it up Ian - you are out of your depth. In the mire created by Americans totally ignoring etymology. |
#85
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torque wrench issues
wrote in message ... On Mon, 1 May 2017 21:25:07 +0100, "Ian Field" wrote: wrote in message . .. On Mon, 01 May 2017 15:08:31 +0700, John B Slocomb wrote: SNIPPED The usually suggested preparation for welding or brazing galvanized materials is to grind all the galvanizing off! ACTUALLY, stripping the zinc with acid is much more effective. Hydrochloric acid makes short work of zinc and produces zinc chloride, which can be used as soldering flux - - - Certainly better than the ****wit who suggested grinding it off and breathing it as dust instead of fumes. The steel would probably contaminate it, but it'd have some uses. Zinc really isn't that toxic - its used in baby powder, hundreds of skin lotions and winter defence vitamin supplements. And no one is making all that much commotion about all the scrap zinc batteries that ended up in landfill. The bogeyman most people think of is mercury. That rots out the central nervous system. And elemental mercury isn't the serious problem it'd made out to be either - it's the organic compounds (which CAN form in disposal - if the mercury combines with carbonaceous materials) I thought it was something like a salt or sulphurous compound - but its a long time since I read up on it. And you're being awfully pedantic about the distinction between elements and their organic compounds for someone with no grasp of etymology. |
#86
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torque wrench issues
"Frank Krygowski" wrote in message news On 5/1/2017 2:49 PM, Ian Field wrote: wrote: On Sun, 30 Apr 2017 21:30:36 +0100, "Ian Field" wrote: Never heard of any warnings against welding zinc passivated steel - only know of cadmium plating being very dangerous. You will only weld or braze galvanized steel in a poorly ventilated space ONCE unless you are REALLY stupid. I have never become aware of the dire consequences of welding zinc plated that are being spouted here. "galvanised" can be plated with *ANY* metal that has a higher galvanic affinity than the host metal. Including cadmium and various other toxic heavy metals. Cadmium poisoning is cumulative and has various routes into the body - its a long slow painful journey to a Darwin award. For a few years I worked assembling electronic equipment on cadmium plated chassis - I've seen with my own eyes the extent to which the plating rubs off on your hands. But if you're too stupid to take it from someone who's been there - Darwin awaits you with outstretched arms. Can you not see your post's internal inconsistency? You have multiple people who have given citations as well as related experiences about welding zinc galvanized steel, but you discount them saying "I have never become aware [of that problem]." I have done and seen others do; things that they claim are instantly injurous - at no time have I observed any such effect. My cites are what I've seen with my own eyes. An old proverb about statistics pretty much says it all. You can present published papers to say anything you want. |
#87
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torque wrench issues
"John B Slocomb" wrote in message ... On Mon, 01 May 2017 22:25:59 -0400, wrote: On Mon, 1 May 2017 22:00:31 -0400, Frank Krygowski wrote: On 5/1/2017 2:49 PM, Ian Field wrote: wrote: On Sun, 30 Apr 2017 21:30:36 +0100, "Ian Field" wrote: Never heard of any warnings against welding zinc passivated steel - only know of cadmium plating being very dangerous. You will only weld or braze galvanized steel in a poorly ventilated space ONCE unless you are REALLY stupid. I have never become aware of the dire consequences of welding zinc plated that are being spouted here. "galvanised" can be plated with *ANY* metal that has a higher galvanic affinity than the host metal. Including cadmium and various other toxic heavy metals. Cadmium poisoning is cumulative and has various routes into the body - its a long slow painful journey to a Darwin award. For a few years I worked assembling electronic equipment on cadmium plated chassis - I've seen with my own eyes the extent to which the plating rubs off on your hands. But if you're too stupid to take it from someone who's been there - Darwin awaits you with outstretched arms. Can you not see your post's internal inconsistency? You have multiple people who have given citations as well as related experiences about welding zinc galvanized steel, but you discount them saying "I have never become aware [of that problem]." Yet you insult those who YOU think are "too stupid to take it from someone who's been there..." Sheesh. Must be the painted cow's twin brother - - - Nah, just another old guy with 20 or 30 years in the trade telling you that you are full of it. A bit more than that, and more than one trade - one thing you're not full of is practical experience. |
#88
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torque wrench issues
"John B Slocomb" wrote in message ... On Mon, 1 May 2017 19:49:36 +0100, "Ian Field" wrote: a great deal deleted know of cadmium plating being very dangerous. You will only weld or braze galvanized steel in a poorly ventilated space ONCE unless you are REALLY stupid. I have never become aware of the dire consequences of welding zinc plated that are being spouted here. "galvanised" can be plated with *ANY* metal that has a higher galvanic affinity than the host metal. Including cadmium and various other toxic heavy metals. I can only assume that you are not from a country where English is the common language as the definition of "galvanized" in the U.S. (and likely in other English speaking countries) is, and I quote, "Covered with Zinc". I'm in an English speaking country that's heard of etymology. |
#89
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torque wrench issues
"John B Slocomb" wrote in message ... On Mon, 1 May 2017 19:51:52 +0100, "Ian Field" wrote: "John B Slocomb" wrote in message . .. On Sun, 30 Apr 2017 18:01:20 +0100, "Ian Field" wrote: wrote in message m... On Sat, 29 Apr 2017 19:53:16 +0100, "Ian Field" wrote: wrote in message news:4eevfc1jbatv5d4g088iqh3n3ls8f4mf35@4ax. com... On Tue, 25 Apr 2017 20:16:22 +0100, "Benderthe.evilrobot" wrote: "John B Slocomb" wrote in message news:schtfc5i6qshna502vhg4pv5f918haa426@4a x.com... 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 news:vmfqfc17u3012cn5jrkkk4r335ol6r5s8 ... 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. I hate to disillusion you but the Japanese word "itai" can be translated into English as "ouch" and is commonly used in everyday conversation. Secondly, the cadmium poisoning you are referring to was specific to mining in Toyama Prefecture. Not to industry per si. Sophistry doesn't magically make you right. You mean that part about "apparently its the noise sufferers make in their death throes"? As I explained the Japanese word "itai" is commonly used as English speakers might use "ouch". Do you think those poor Japanese dying in agony are saying "ouch - ouch". Saying I said what I said is a very weird way to try to contradict me. I simply quoted what I'd read because I know how easy it is to confuse you. Don't you think "ouch" would be fairly predictable when their skeleton is disintegrating.......................... |
#90
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torque wrench issues
On 5/2/2017 1:44 PM, Ian Field wrote:
"Frank Krygowski" wrote in message ... On Monday, May 1, 2017 at 4:14:24 PM UTC-4, Ian Field wrote: "galvanised" is galvanic protection - which can include any of several toxic heavy metals. Some people here seem to think it can only mean zinc. In the U.S. "galvanize" means to coat steel or iron with zinc. (Alternate meaning: to spur into action.) It may be that British usage is different, I suppose. But I don't find evidence of that. The British usage means to plate with galvanic protection. Do you have evidence of that? Everything I find online speaks of zinc, just as in the U.S. -- - Frank Krygowski |
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