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Yup. There's a reason I sperg the gently caress out about brakleen brands and contents. I won't buy a can without reading the ingredients list, because I know I'm going to be impatient and weld/torch parts that have been brakleened. UV/electric arc + chloro/fluoro anything = bad news. People have died and been severely permanently injured because of this.
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Apr 20, 2016 21:58
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psh we have 55 gallon drum of that poo poo and use it to clean our floors along with floor soap regularly. poo poo evaporates almost instantly on most surfaces. The cans are worse cause of all the propellant, we just have our own spray bottles we charge with shop air. Don't drink it and you will be fine.
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Apr 20, 2016 22:21
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If you start smelling something reminiscent of fresh cut hay, GTFO. Phosgene is a pretty common PIC (product of incomplete combustion) for chlorinated solvents though. Don't burn that poo poo.
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Apr 20, 2016 22:24
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R-134a and the new R-1234yf can both decompose due to heat into hyrogen floride. Also, apparently R-1234yf is also highly flammable in air if its concentration is between 6.8% and 21.5%. A/C chemicals are nasty poo poo apparently and I never knew how bad they were until we looked up the msds sheet for the new stuff. Except R-744 which is apparently pure CO2, but requires extremely high pressures to work. Oh, and just for kastien, the chemical name for R1234yf is tetrafloropropene.
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Apr 20, 2016 22:27
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Re: Trailing arm: seems like you got the best possible outcome out of this.xzzy posted:Or maybe tire shops are barely a step above quick lube joints and hire the most incompetent slack jawed buffoons they can dig up because how hard can replacing a tire really be? A tire-world torque job caused me to do this, completely by hand, in the parking lot of a gas station one cold night while trying to loosen _any_ of the 5 lugs on a wheel with a flat   
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Apr 20, 2016 22:37
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Electrical Deoxit
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Apr 20, 2016 23:06
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Elmnt80 posted:R-134a and the new R-1234yf can both decompose due to heat into hyrogen floride. Also, apparently R-1234yf is also highly flammable in air if its concentration is between 6.8% and 21.5%. A/C chemicals are nasty poo poo apparently and I never knew how bad they were until we looked up the msds sheet for the new stuff. Except R-744 which is apparently pure CO2, but requires extremely high pressures to work. But using any of the hydrocarbon-based refrigerants in your automobile AC, that's Bad, because flammable! I'm perfectly happy with R152a, thank you very much (though my cutlass still has ES-12a Envirosafe hydrocarbon/134a blend, because it's working, and I don't want to vent it). At lease, it was working when I last drove it before the transmission stopped shifting. Incidentally, I am now and forever going use the mnemonic "1-2-3-4 -you're hosed" to remember the new refrigerant.
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Apr 21, 2016 00:30
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FopeDush posted:Re: Trailing arm: seems like you got the best possible outcome out of this. I have only ever hosed a tool that badly on a front wheel bearing nut on a 1992 Mazda 626 V6. I had a cheap breaker bar with a 6-foot cyclone fence post on the end of it, engine running with an apprentice standing on the brakes to immobilise the hub. I thought I felt it going so I kept leaning on it. The breaker bar popped, I fell over, I swore a lot. We ended up calling a truck shop down the road to borrow their inch-drive rattle gun, which still took a solid couple of minutes of BAP BAP BAP BAP to get it to move. edit: re A/C chat. I knew a dude about 15 years ago who would smoke while doing A/C work. Just chain smoke while vac'ing them down and re-gassing systems. He died of lung cancer a couple of years ago at the ripe old age of 38. Memento fucked around with this message at 00:37 on Apr 21, 2016 |
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Apr 21, 2016 00:34
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Darchangel posted:Incidentally, I am now and forever going use the mnemonic "1-2-3-4 -you're hosed" to remember the new refrigerant. heh hehe heheheheheh Wikipedia posted:In December 2012, it was reported that tests by Mercedes-Benz showed that the substance ignited when researchers sprayed it and A/C compressor oil onto a car's hot engine. Stefan Geyer, a senior Daimler engineer who ran the tests, stated "We were frozen in shock, I am not going to deny it. We needed a day to comprehend what we had just seen." Combustion occurred in more than two thirds of simulated head-on collisions. The engineers also noticed etching on the windshield caused by the corrosive gases. BMW, and VW-Audi agreed with Mercedes and left the SAE R-1234yf CRP Team, stating that the performed tests are not sufficient to fully judge the safety of their vehicles. The German Automakers have been leaning towards carbon dioxide refrigerant which is safer for both passengers and the environment. 
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Apr 21, 2016 02:20
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It seems more like the German automakers carefully constructed tests that would make it ignite so they'd have an excuse not to pay for the transition to the new refrigerant.
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Apr 21, 2016 03:21
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Yes, but that's what you do: put systems (in this case, cars) in worst case scenarios and determine the outcome. If the outcome is fiery death, then it is not acceptable.
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Apr 21, 2016 03:26
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Alereon posted:It seems more like the German automakers carefully constructed tests that would make it ignite so they'd have an excuse not to pay for the transition to the new refrigerant. https://www.en.uni-muenchen.de/news/newsarchiv/2014/kornath_refrigerant.html I mean I'm no scientist but I think I'll stick to slightly warmer/ozonedepletier AC than risk inhaling that in the event of an otherwise non-fatal engine fire.
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Apr 21, 2016 03:32
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H110Hawk posted:https://www.en.uni-muenchen.de/news/newsarchiv/2014/kornath_refrigerant.html I thought R152 was in the running to replace R134?
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Apr 21, 2016 03:38
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totalnewbie posted:Yes, but that's what you do: put systems (in this case, cars) in worst case scenarios and determine the outcome. If the outcome is fiery death, then it is not acceptable. H110Hawk posted:https://www.en.uni-muenchen.de/news/newsarchiv/2014/kornath_refrigerant.html
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Apr 21, 2016 04:26
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Alereon posted:Note that independent testing by actual scientists who do not have a vested interest in the results of the tests and actually care deeply about safety (like the SAE) took that into account and showed that it's safe. A small group of German automakers want to get out of paying to upgrade their refrigeration system so are bullshitting that it isn't. Do you really believe the automakers are taking your side against a government conspiracy to make your car use an unsafe refrigerant? It's not like Mercedes engineers have a lot of credibility in my book either. 
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Apr 21, 2016 04:28
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Seat Safety Switch posted:It's not like Mercedes engineers have a lot of credibility in my book either. Hey it worked. 
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Apr 21, 2016 04:49
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FopeDush posted:Re: Trailing arm: seems like you got the best possible outcome out of this. Laughing and grimacing at the same time over here.
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Apr 21, 2016 05:08
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Of all things, this was done by an oil pan bolt. Doesn't say much for the quality of the wrench. 
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Apr 21, 2016 05:35
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Alereon posted:It seems more like the German automakers carefully constructed tests that would make it ignite so they'd have an excuse not to pay for the transition to the new refrigerant. Alereon posted:Note that independent testing by actual scientists who do not have a vested interest in the results of the tests and actually care deeply about safety (like the SAE) took that into account and showed that it's safe. A small group of German automakers want to get out of paying to upgrade their refrigeration system so are bullshitting that it isn't. Do you really believe the automakers are taking your side against a government conspiracy to make your car use an unsafe refrigerant? I'd agree with you, except the German manufacturers' response is to use CO2 refrigerant, which is harder to handle and more expensive to implement due to the much higher pressure requirements, as well as even less damaging to the environment than 1234yf. They're making things harder for themselves, not easier - and SAE's best interests don't necessarily translate to choosing the safest option, SAE's best interests translates to "what makes our members happy and is safe enough that we can get away with it". 1234yf can be used in systems that are basically the same as 134a systems, while CO2 requires a whole new much higher pressure system design - GM and Chrysler sure as hell aren't going to spend any money developing new hardware if they don't have to. CO2 is effectively inert. Hell, a CO2 refrigerant leak during a crash would likely help put out a fire, if anything. -shrug- not my monkey, not my circus, but I don't think it's as clear cut as it might seem to be. totalnewbie posted:Yes, but that's what you do: put systems (in this case, cars) in worst case scenarios and determine the outcome. If the outcome is fiery death, then it is not acceptable.
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Apr 21, 2016 07:38
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smax posted:If you start smelling something reminiscent of fresh cut hay, GTFO. It's probably too late by then. Isn't something like 4ppm of Phosgene all you need to get hosed up? Also, if 1234yourefucked is flammable, then why aren't we using nice, friendly, chlorine/fluorine-free propane instead? Pomp and Circumcized fucked around with this message at 08:25 on Apr 21, 2016 |
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Apr 21, 2016 08:21
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Because the range at which it will ignite is relatively narrow compared to propane most likely.CommieGIR posted:I thought R152 was in the running to replace R134? As far as I could find, it was found to be more flamable than R-1234yf and was therefore deemed unsuitable. Someone I was was talking to mentioned there was also an interesting test where a simulated leak the new stuff was ignited by an airbag deployment and managed to blow out the windows of the test vehicle. Can't find a source for this story though. 
Elmnt80 fucked around with this message at 08:29 on Apr 21, 2016 |
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Apr 21, 2016 08:27
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I believe the germans' point was that on its own 1234yf wasn't actually super flammable (as per the SAE's findings), but caught on fire much more easily when mixed with standard A/C compressor oil (as it would be in-system)
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Apr 21, 2016 08:56
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Garbage Dick posted:Hey it worked. What is going on here?
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Apr 21, 2016 14:06
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Crotch Fruit posted:What is going on here? Italian Engineering (the two intake valves being actuated by one tappet) joat mon fucked around with this message at 14:36 on Apr 21, 2016 |
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Apr 21, 2016 14:18
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Crotch Fruit posted:What is going on here? Biturbo.
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Apr 21, 2016 14:19
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ShittyPostmakerPro posted:It's probably too late by then. Isn't something like 4ppm of Phosgene all you need to get hosed up? Permanently? Cause if so that would explain my posting.
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Apr 21, 2016 14:34
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Alereon posted:Note that independent testing by actual scientists who do not have a vested interest in the results of the tests and actually care deeply about safety (like the SAE) took that into account and showed that it's safe. A small group of German automakers want to get out of paying to upgrade their refrigeration system so are bullshitting that it isn't. Do you really believe the automakers are taking your side against a government conspiracy to make your car use an unsafe refrigerant? All of the major standards organizations are influenced by the desires of the big manufacturers to some degree. It's not a government conspiracy, it's just business (So a different kind of conspiracy). Example: When AS9100 went through it's C revision in 2009 Boeing basically wrote a lot of the major changes due to the problems they had with suppliers when building the 787. AS9100C is an SAE standard. Disgruntled Bovine fucked around with this message at 14:48 on Apr 21, 2016 |
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Apr 21, 2016 14:45
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^ Agreed. The reason why is pretty simple - the SAE is the society of automotive engineers, AKA people who work in automotive engineering, which pretty much means they work for the companies the standards apply to. There's also some aerospace guys involved too (*ahem* me, though I don't write standards or sit on any committees because I don't really enjoy it, and my membership lapsed a while ago...) of course.
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Apr 21, 2016 15:04
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kastein posted:There's also some aerospace guys involved too (*ahem* me, though I don't write standards or sit on any committees because I don't really enjoy it, and my membership lapsed a while ago...) of course. Was the stuff you touched mostly things that cross-over between aerospace and automotive, like tires and hydraulic systems and such?
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Apr 21, 2016 18:15
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Not really. I'm an electrical engineer and I design flying cars for a living, so none of the systems you mentioned, but a little from column A and a little from column B when it comes to automotive/aerospace. 
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Apr 21, 2016 19:09
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Not using propane does seem pretty dumb. It's only got about 3 times the Global Warming Potential of CO2, runs at similar pressures to R-134a etc, and is pretty tame as far as handling. I guess the main issue is it's 93 cents per pound vs about 8 for CO2. Designing a few high-pressure refrigerant systems is probably cheaper in the long run, if it were ever forced. (For comparison, R-134a has a GWP of about 3800 over 20 years, R-1234yf roughly 4. R-12 is about 2400, which is way lower than 134a, but there's the whole ozone depletion thing.)
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Apr 21, 2016 20:32
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The reason is probably the flammability or cost of a compatible lubricant (unsure what's miscible with propane) rather than cost of the refrigerant. Propane burns quite nicely. e: most info I can find says flammability is the concern. Personally I have no problem with it, I'd rather use a flammable refrigerant that burns to produce CO2 and H2O than one that burns to produce CO2, H2O, and hot hydrofluoric acid vapors, but hey, I'm no bean counter or AC systems engineer. kastein fucked around with this message at 21:38 on Apr 21, 2016 |
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Apr 21, 2016 21:34
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There is only a small amount of refrigerant in the system. A small amount of fire isn't nearly as harmful as a small amount of some of that toxic poo poo which was recently discussed. I pump gallons of propane through my engine compartment anyway, and nothing has exploded yet. In a wreck, I can't see a small propane fire causing more harm than a facefull of hydrofluoric gently caress-you-up-ide
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Apr 21, 2016 21:47
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Chlorinated brake cleaner + welding = WWI poison gas. E: man I'm terrible at thinking in on the last page when I'm not when on the phone. FatCow fucked around with this message at 22:31 on Apr 21, 2016 |
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Apr 21, 2016 21:50
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FatCow posted:Chlorinated brake cleaner + welding = WWI poison gas.  
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Apr 21, 2016 22:09
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Yeah that's the argument I never understood; propane is highly flammable, unlike gasoline, known for its inert properties. I mean propane vapor expands faster, but by the same token it'd burn up or dissipate a lot faster.
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Apr 22, 2016 00:02
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I found this in one of the drill presses in the shop. I've seen router bits and endmills with bidirectional flutes before, but never a drill bit. Looks like a student managed to get one to un-twist, then skulked away in shame without even disposing of the evidence.
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Apr 22, 2016 00:38
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Sagebrush posted:I found this in one of the drill presses in the shop. This is me after every honda brake job 
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Apr 22, 2016 01:22
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I was witness to a pretty horrible mechanical failure today. I was getting off the highway at an exit where the off-ramp was backed up a few cars onto the highway. I could see the row of cars as I pulled up. In front of me was a civic and in front of that was a cement truck with the drum spinning. We inched forward a couple times, then sat still for a good minute. I couldn't understand why as the exit doesn't have a light, but rather a merge at the bottom of the ramp which usually moves along slowly but steadily. Then I noticed that the drum on the cement truck had stopped turning.  I couldn't see around the truck so I asked my passenger if they could, and they hopped out of the car to look around it. There were no more cars backed up in front of the truck, but there was a long line behind us. I managed to maneuver around the car in front of me and the ramp was completely clear, just the driver in his truck talking on his cell phone. I imagine the conversation went something like this: "I have a full load of cement and the truck just broke down blocking a highway offramp. Get here with a pump truck as fast as you loving can." About 20 minutes later we came back to get on the highway and the truck was still there, the drum still wasn't turning, and there was nobody attempting to offload the cement. I don't know much about how long it takes cement to dry in a truck, but I imagine by that point things were starting to harden. I have a feeling someone's in for a very long couple of days (weeks?) with a jackhammer inside that drum. Also the police had closed down one of the two lanes so people could get around the truck to the exit (only a small gap was left), so there was a 5 mile jam backed up behind it.
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Apr 22, 2016 01:48
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Sagebrush posted:I found this in one of the drill presses in the shop. DIY left-handed bits.
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Apr 22, 2016 02:55
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