territorialmillworks Posted January 8, 2012 Share Posted January 8, 2012 I've read lots of warnings about the toxicity of galvanize so I wanted some input before doing myself harm...Need to weld on to one leg of a hot dipped galvanized triangular shaped piece of steel that measures 24 X 24 x24 and 6" in depth. My thought was to stand it up in a plastic tub with vinegar on the leg that I need to weld to. The piece is made from 1/2 X 6 plate and will require multiple fillet welds, a lot of heat so I'm assuming that I'll need to remove a larger area. Will vinegar eat deep enough to remove the hot dip? Can I do this with acid instead? I have a carbon filter respirator and arm length rubber gloves. Thanks for your help, Keith Quote Link to comment Share on other sites More sharing options...
Larry H Posted January 8, 2012 Share Posted January 8, 2012 you didn't say how many inches of weld.....grind the galv away and use 6011 for the root pass and go over with a 7018 but use good ventilation grinding is no worse than the weld, the galv will burn away anyway so get used to it. Alum. paint over it Quote Link to comment Share on other sites More sharing options...
Glenn Posted January 8, 2012 Share Posted January 8, 2012 I do not recall "get used to it" as being anywhere near safe. Grinding galv puts lots of Zinc dust into the air which is NOT GOOD. Use LOTS of ventilation. BIG FANS both when grinding and when welding. You want any zinc fumes to be moved as far away from YOU as possible. Quote Link to comment Share on other sites More sharing options...
Larry H Posted January 8, 2012 Share Posted January 8, 2012 I meant get used to the fact that the galv goes away, and you have to paint it or it will rust. I've been welding galv pipe for thirty years...don't like it, but if thats the job..... you have to know how to do it, safely Quote Link to comment Share on other sites More sharing options...
pkrankow Posted January 8, 2012 Share Posted January 8, 2012 Muriatic acid will remove it quite quickly in minutes. (vs hours with vinegar) You may try washing instead of dipping since it is potent. It will gas off hydrogen, and may aerosolize the acid, so take precautions. Wash well with soap and lots of water to neutralize. Melting point of zinc is 787F, there will be vapor at that point too. You can wrap with wet rag (water) to stop heat from moving to the unstripped areas, but need to strip a suitable amount. Re-wet the rag as it dries out. There are "cold galvanizing" and Zinc sprays that work fairly well, they are a paint vehicle with a high zinc load in them There are other steel protecting paints that can be used in place of galvanization. Sadly they are not generally as good as hot-dip. Grinding is probably safer than heating because the dust can be more easily protected against with a mask than the fumes. Phil Quote Link to comment Share on other sites More sharing options...
Glenn Posted January 8, 2012 Share Posted January 8, 2012 Smithy-1 As long as it is done safely, Thanks for clearing that up. Quote Link to comment Share on other sites More sharing options...
SmoothBore Posted January 8, 2012 Share Posted January 8, 2012 Grind it off.Acid etching has just as many negatives as grinding, ... PLUS disposal of the HAZ-MAT acid. . Quote Link to comment Share on other sites More sharing options...
Ferrous Beuler Posted January 9, 2012 Share Posted January 9, 2012 Another thing concerning galvy is the very popular "turkey in a garbage can" method of cooking a turkey. Are there any health concerns associated with cooking food with a galvanized garbage can? Seems to me that there would be. http://www.google.com/imgres?imgurl=http://www.scoutingthenet.com/Cooking/Turkey/images/near_end.jpg&imgrefurl=http://www.scoutingthenet.com/Cooking/Turkey/index.php&h=242&w=250&sz=15&tbnid=1U8e6aavd44bhM:&tbnh=97&tbnw=100&prev=/search%3Fq%3Dturkey%2Bin%2Ba%2Bgarbage%2Bcan%2Bpictures%26tbm%3Disch%26tbo%3Du&zoom=1&q=turkey+in+a+garbage+can+pictures&docid=PPBrDNP6KZeskM&hl=en&sa=X&ei=oUgKT-SeBcjx0gHe6ajQAQ&sqi=2&ved=0CEQQ9QEwCQ&dur=3272 http://www.google.com/imgres?imgurl=http://elpasotimes.gannettonline.com/gns/thanksgiving/tfoto-tcan2.jpg&imgrefurl=http://elpasotimes.gannettonline.com/gns/thanksgiving/20041110-53075.html&h=331&w=240&sz=30&tbnid=50XR1LLSrdgomM:&tbnh=93&tbnw=67&prev=/search%3Fq%3Dturkey%2Bin%2Ba%2Bgarbage%2Bcan%2Bpictures%26tbm%3Disch%26tbo%3Du&zoom=1&q=turkey+in+a+garbage+can+pictures&docid=RIpFsGVByzGuSM&hl=en&sa=X&ei=oUgKT-SeBcjx0gHe6ajQAQ&sqi=2&ved=0CEAQ9QEwCA&dur=481 Quote Link to comment Share on other sites More sharing options...
dkunkler Posted January 9, 2012 Share Posted January 9, 2012 Another thing concerning galvy is the very popular "turkey in a garbage can" method of cooking a turkey. Yikes! First time I've seen that, don't want to try it. Quote Link to comment Share on other sites More sharing options...
macbruce Posted January 9, 2012 Share Posted January 9, 2012 Grind it off.... PLUS disposal of the HAZ-MAT acid. Grinding probably would produce a better local area removal of the galv for welding than acid. .......But mild muriatic acid isn't high on the haz scale......I've seen stone masons and crete heads wash down their work many times with HCL and it runs off into the ground after a good hosing down.....OSHA/EPA would be all over this widespread practice if it was that detremental to the enviroment or the workers........Use with caution and do it outdoors..... B) Quote Link to comment Share on other sites More sharing options...
r smith Posted January 9, 2012 Share Posted January 9, 2012 Grind it off and use a wheel made for aluminum on the galvy, it wont load up or use coarse grit sanding disc like 36 or so. Get back about 1/2" from the weld should be enough. Quote Link to comment Share on other sites More sharing options...
Woody Posted January 9, 2012 Share Posted January 9, 2012 Grinding probably would produce a better local area removal of the galv for welding than acid. .......But mild muriatic acid isn't high on the haz scale......I've seen stone masons and crete heads wash down their work many times with HCL and it runs off into the ground after a good hosing down.....OSHA/EPA would be all over this widespread practice if it was that detremental to the enviroment or the workers........Use with caution and do it outdoors..... Anything with a pH of 2 or less is a Characteristic Hazardous Waste by the characteristic of corrosivity, 40 CFR Part 261. Waste Muratic Acid falls into that category. The penalty for illegal disposal of a hazardous waste is a fine not to exceed $50,000 and or 5 years in prison. Cement being on the alkaline side of the pH scale would tend to neutralize the acid although to what extent could only be determined by testing. Myself, I would be careful about advising people to just dump something on a public forum that has world wide access. There are several stickies on this site on the effects of Zinc fumes I would suggest that you read them. If one uses proper respiratory protection with adequate ventilation, grinding and welding should not be a problem. Quote Link to comment Share on other sites More sharing options...
ThomasPowers Posted January 9, 2012 Share Posted January 9, 2012 Zinc chloride is the classic tinner's flux used to solder sheet metal, so your toxic waste is actually a useful commodity. If you want to dispose of it and if your used acid still has too low a ph, add lime until it's neutralized. (just regular lime unslaked is NOT needed!) If the original was hot dipped galvanized you should probably look into doing the same for the repair/modification! Quote Link to comment Share on other sites More sharing options...
pkrankow Posted January 9, 2012 Share Posted January 9, 2012 Honestly, the turkey in the trash can oven amuses me more than disturbs me. Zinc is a dietary requirement. (edit: I looked, my daily multivitimin has 12mg of zinc) Phil Quote Link to comment Share on other sites More sharing options...
Jason @ MacTalis Ironworks Posted January 10, 2012 Share Posted January 10, 2012 Honestly, the turkey in the trash can oven amuses me more than disturbs me. Zinc is a dietary requirement. (edit: I looked, my daily multivitimin has 12mg of zinc) PhilZinc, ingested is a necessary mineral... fumed zinc in the resperatory system is toxic. Handling zinc isn't a problem either... it really is just a matter of how it is getting into the body, and of course, the quantity. Quote Link to comment Share on other sites More sharing options...
macbruce Posted January 10, 2012 Share Posted January 10, 2012 Well the thread is about advice so I'll limit this response to some don't and facts.....Dont ever mess with acid if you aren't knowedgeable with handling it, as with fire, machinery and paint etc.......working with acid indoors is especially dangerous, don't do it...............Fact: Stone masons, bricklayers and concrete workers routinely wash their finished work with muriatic acid they get from places like Home Depot,Lowes,Ace etc......It's available in the section where concrete and such is sold for that purpose. They spray the stuff on mostly and never have I seen them take any special precautions other than diluting it with water for disposal ..........They do on occasion wear protective clothing,goggles and resperators. They can be real inconsiderate when other trades are present and are roundly cursed at times when they give no warning.Those fumes and airborn droplets are NASTY! Kieths project with it's large surface will make a lot of fumes if doused with the stuff so wear the protective clothing and resperator if you choose to do so Keith, myself I would simply get upwind of it but that's a risk I'm personally willing to take..... :) Quote Link to comment Share on other sites More sharing options...
Tom Allyn Posted January 10, 2012 Share Posted January 10, 2012 When cleaning masonry we would dilute the muriatic acid down to about a 5% solution. Muriatic acid for the construction/masonry industry is typically bottled in a 20%-30% solution with 70%-80% water. When you rinse down the wall after washing you are further diluting the solution down many times. The result in the soil would be a fraction of a % solution. Not saying it's OK, just providing info. Quote Link to comment Share on other sites More sharing options...
kpdavis2000 Posted September 6, 2015 Share Posted September 6, 2015 Hello, I have wanted to get into casting so that i can make bars for easier forging. I have a couple of galvanized steel fence posts that i want to melt but I am aware of the health hazards of zinc fumes, so I would like to know if anybody can tell me how to remove the coating safely with no health hazards. Quote Link to comment Share on other sites More sharing options...
Frosty Posted September 6, 2015 Share Posted September 6, 2015 Welcome aboard KP, glad to have you. If you'll put your general location in the header you might be surprised how many of the IFI gang live within visiting distance.Please don't take this the wrong way but if you have to ask you don't know enough to attempt it on any level.First casting steel for home use is terribly wasteful of time fuel and is tremendously dangerous. There are guys on this forum who make their own iron and steel but certainly NOT by melting scrap. 10 lbs. say a coffee mug size crucible worth of molten steel has the potential explosive power of around a CASE of 40% dynamite. One mistake and you're wearing a couple lbs. of molten steel in the burning remains of your shop.Stripping galvy is easy to do, a little research will answer that question. I'm not going to here, you need the practice doing real research.I'm not being mean, we like to see folk being successful but it takes effort on all levels on your part.For something to forge, especially just beginning keep it simple and buy some mild or A36 steel. It's a known quantity so the techniques you learn are applicable. Scrounging is a necessary blacksmith skill but learning to evaluate what you're salvaged is a different set of skills you don't need to try to learn while developing basic hammer control and forging skills.Frosty The Lucky. Quote Link to comment Share on other sites More sharing options...
Charles R. Stevens Posted September 7, 2015 Share Posted September 7, 2015 Fraid I wont deffy Frostys mentoring. After you figure out how to get the galvy off look at the tension bar/rods. Quote Link to comment Share on other sites More sharing options...
ThomasPowers Posted September 7, 2015 Share Posted September 7, 2015 Wow casting your own bars to forge would probably be only 10 to 100 times MORE expensive than buying new steel; just the cost of fuel, crucibles, hundreds of dollars in safety equipment, and the fact that what you melt is not necessarily what you get in the pour...Can you explain the *why* you want to do this? Quote Link to comment Share on other sites More sharing options...
Steve Sells Posted September 9, 2015 Share Posted September 9, 2015 also the legally required HAZ MAT disposal for the zink you removed will cost even more, as we explained in the other thread about this Your comment about wanting to get into casting to make forging easier make no sense at all. Quote Link to comment Share on other sites More sharing options...
Gorō Posted October 3, 2016 Share Posted October 3, 2016 I always hear people telling me dip in acid bath of muriatic acid but can I use muriatic acid to brush it on??? I want to use a brush and just wipe down my anvil. smaller galvanised fittings I can get away with a bucket of acid. But the anvil is too big. Quote Link to comment Share on other sites More sharing options...
Buzzkill Posted October 3, 2016 Share Posted October 3, 2016 Steel exposed to acid in the presence of oxygen will rust FAST. The muriatic or vinegar baths work well to strip zinc coatings or derust items, BUT only if they are submerged so that oxygen can't get to the steel's surface. You may have seen on here people talking about using muriatic acid in their shop and just from the fumes nearly everything that can rust within 20 or 30 feet of where they were using it gets rusty. I think there are better options for your anvil, but since all I've ever done on mine is wire brushes and wheels I'll leave the wipe down suggestions to someone else. Quote Link to comment Share on other sites More sharing options...
Steve Sells Posted October 4, 2016 Share Posted October 4, 2016 I gotta wonder about people that make such a strange post like this one, then never return to IFI again Quote Link to comment Share on other sites More sharing options...
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