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Hey guys, im by far not better than a welding hobbyist, However ive gone through about 300 meters of stainless and am about to go through another 140 or so this week.Question how do you limit or avoid the discoloration that pickling paste leaves once applied? When i do it it comes out all shiny and lovely but you can see the difference in colour as to that of the untreated metal.Is it technique? do i have to carefully apply a thin strip or do i need to change pickling pastes? I would love your feedback because i want to start making my work look more aesthetically pleasing.Cheers
Reply:Man, pickling paste if it is hydrofluoric acid is very very nasty stuff. Be very careful with it. I hope you are wearing an acid gas respirator. I know a guy who permanently burnt his lungs breathing only a small amount of acid. He has only 50% lung capacity now. Plus a gram of hydrofluoric acid can contaminate ten thousand gallons of ground water. Hopefully you are using mineral acid. still very bad stuff and you should wear an acid gas respirator. And even the rinse water for both should be contained and treated as toxic waste. Sorry to be all preachy but that stuff is just bad. In order to make surface color consistent you would have to passivated the entire piece. When asked this question I always say the same thing. No need to pickle at all. You just have to clean it with a SS wire brush right after you weld while it is still hot. The discoloration will come right off. If by chance that isnt practical then get one of these: http://news.thomasnet.com/fullstory/...rnative-599383Welding everything, from the crack of dawn to a broken heart.
Reply:You state that a concentration of 1/37,829,604 or roughly 26.5PPB of HF in water would be considered contaminated? Seems like a pretty tight spec, considering that HF in H2O ionizes to a good extent, giving H3O+ and F-, which is fluorine, you know, the stuff that is good for your teeth? EPA says you can have 4 PPM Max , 1PPM recommended F- in your water. Lastly, there is some documentation that the flourine level in your saliva is ~40PPB due to H2O fluoridation.http://www.ncbi.nlm.nih.gov/pubmed/17333303Most of the above according to WikipediaJust sayin, is all
Reply:thanks for the insight fellas, im talking all the precaution whilst handling the paste, but good to know that you have to cover the whole item for a uniform finish. CHeers |
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发表于 2021-9-1 00:00:32