how do you tell the difference between galvinized and non-galvinized sheet metal??

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Hi all,I am just learning to weld and need to practice on some sheet metal. I understand the issues with welding galvanized steel and would like to stay away, if possible. Is there away to make sure the sheet metal is not galvanized?I'm thinking of going to a metal recyclers, so the metal wont be marked.Thanks,Jerry
Reply:It's kind of shiny. All the crap they sell at autozone is galvanized. Same with a fence post. And all that metal at the hardware store with the holes in it, that they use to hang garage door openers.Torchmate 2x2 CNC with Flashcut CNC controlsHypertherm Powermax45 Esab ET220i Razorweld 195 MigRazorweld 200ac/dc TigTormach 770, Tormach xstechRazorweld, Vipercut/Vipermig, SSC Foot Pedal Dealer
Reply:After doing some more searching, if it rust it is not galvanized, duhAlso, if you lick it, it leaves a chalky feeling on your teeth. Don't think I will be licking any steel at the recyclers thoughThanks Originally Posted by GambleIt's kind of shiny. All the crap they sell at autozone is galvanized. Same with a fence post. And all that metal at the hardware store with the holes in it, that they use to hang garage door openers.
Reply:Galvanized metal looks like thisThings like metal corrugated sheets are galvanizedTake a peek here  https://www.google.co.uk/search?q=ga...w=1680&bih=935 for some more ideas
Reply:This was my impression also, but when I looked at the sheet metal at Home Depot, it did not have the crystallized look and it is marked galvanized. I believe it is the type of plating process used that causes the crystallized look. Originally Posted by Gerry1964Galvanized metal looks like thisThings like metal corrugated sheets are galvanizedTake a peek here  https://www.google.co.uk/search?q=ga...w=1680&bih=935 for some more ideas
Reply:You must not confuse Galvanized metal with Zinc Plated metal, They both have zinc, The galv is Hot dipped, where the metal is lowered into a bath of molten Zinc, when the metal is coated and lifted out it generally has that crystal look to it, its just where the zinc has cooled down.Zinc Plating is something completely different where the Zinc is deposited onto the Metal at molecular level, Its a plating process done with electricity and Zinc anodes, so its a very thin fine coating of zinc. Although the process for zinc plating and zinc galvanizing are basically the same, there really is a big difference. The difference is the thickness of the zinc that is applied to the surface of the steel. Zinc plating is generally applied using an electric current. This current is run through a zinc salt solution that has the pieces that are to be coated in it. The process leaves a coat of pure zinc on the item. The cheap hardware usually only gets about 15 microns and the more expensive products get more.To get the best type of galvanized product you need to be certain that is has been hot dip galvanized. This adds a coating that is 50 microns thick, which means you get over 10x the protection with galvanization. This process dips a piece into molten zinc. This process makes the item stronger and more resistant to corrosion. If you are buying an item that is going to be exposed to a lot of rain and other things that have a highly corrosive effect, this is the one you want. However because most people, everyday consumers, are not conversant of the differences in the processes, they buy the lesser items and find that they do not hold up as well.Items with zinc coating are really not suited for use in the out-of-doors. If you purchase zinc plated hinges and bolts for things that will be exposed to the elements for any length of time you will see that you have to replace them over and over again. Although the items that are zinc-plated look great at the beginning, in about six months time you begin to see the change. The hot dipped hardware looks a bit duller but that is because of the thickness. In this case, dull means good and shiny…not so much.The next time you are in the market for a zinc coated part, remember the differences between zinc plating and zinc galvanizing.
Reply:thanks gerry1964.  ive always scratched me head when looking at plated metal.  what do you thing of spray on cold galvanize?  i guess that will hold up even less.Everlast PowerTIG 185
Reply:Originally Posted by ArcForcethanks gerry1964.  ive always scratched me head when looking at plated metal.  what do you thing of spray on cold galvanize?  i guess that will hold up even less.
Reply:weld on it, you'll figure it out real quick."Si Vis Pacem Para Bellum"Lincoln Idealarc 250 AC/DCMillermatic 251   Syncrowave 300   30A spoolgunLincoln MP210Hypertherm 45(2) LN 25(2) Lincoln Weldanpower 225 CV(4) SA200   1 short hood    SA250    SAM 400
Reply:In any case he is gonna be picking up crap just to practice on so he should be using a respirator because it will be mixed junk.  Anyone got any suggestions.  All I commonly see are the charcoal nose-mouth masks at my local welding supply place. They have active charcoal and would help a bi and do fit under most hoods..
Reply:Welding Galvanized steel and breathing the smoke makes you sick to your stomach but is not necessarily dangerous to your health. If you feel even the slightest bit of nausea drink a glass of milk and it will go away like magic.  Mac
Reply:Originally Posted by Tool MakerWelding Galvanized steel and breathing the smoke makes you sick to your stomach but is not necessarily dangerous to your health. If you feel even the slightest bit of nausea drink a glass of milk and it will go away like magic.  Mac
Reply:I'll say right off I agree completely with the smoke bad no matter what kind it is.  But I'm 75 and not dead yet. and have been welding for my entire life, and smoked cigs for 40 years. I do wonder sometimes why I'm still here.  Iv'e had a lot of friends that were painters and most of them died of alcohol. I was working in LA when you were there.  worked for Master Metal works.  Got sick a couple times on  Brass fumes. that is zink poison also. Now I don't smoke anything , don't even Barbecue. I still weld almost every day.  Mac
Reply:You might just be beating the odds. Drinking milk eases the symptoms but almost certainly leaves the poisons in your bloodstream. Id look up a good respirator and use that. Call 3M if you need application selection. A lot of the old firefighters I know have similar attitudes about wearing airpaks. Lots of them die miserable deaths from the toxins inhaled over a career...some of the newer guys that believe their advice wind up with debilitating permanent lung damage.Hobart Stickmate LX235AC/160DCRanger 305GVictor 315 O/A rigHope to acquire in the next couple of years: Hypertherm PM45 and Dynasty 200DX
Reply:Originally Posted by Gerry1964You must not confuse Galvanized metal with Zinc Plated metal, They both have zinc, The galv is Hot dipped, where the metal is lowered into a bath of molten Zinc, when the metal is coated and lifted out it generally has that crystal look to it, its just where the zinc has cooled down.Zinc Plating is something completely different where the Zinc is deposited onto the Metal at molecular level, Its a plating process done with electricity and Zinc anodes, so its a very thin fine coating of zinc. Although the process for zinc plating and zinc galvanizing are basically the same, there really is a big difference. The difference is the thickness of the zinc that is applied to the surface of the steel. Zinc plating is generally applied using an electric current. This current is run through a zinc salt solution that has the pieces that are to be coated in it. The process leaves a coat of pure zinc on the item. The cheap hardware usually only gets about 15 microns and the more expensive products get more.To get the best type of galvanized product you need to be certain that is has been hot dip galvanized. This adds a coating that is 50 microns thick, which means you get over 10x the protection with galvanization. This process dips a piece into molten zinc. This process makes the item stronger and more resistant to corrosion. If you are buying an item that is going to be exposed to a lot of rain and other things that have a highly corrosive effect, this is the one you want. However because most people, everyday consumers, are not conversant of the differences in the processes, they buy the lesser items and find that they do not hold up as well.Items with zinc coating are really not suited for use in the out-of-doors. If you purchase zinc plated hinges and bolts for things that will be exposed to the elements for any length of time you will see that you have to replace them over and over again. Although the items that are zinc-plated look great at the beginning, in about six months time you begin to see the change. The hot dipped hardware looks a bit duller but that is because of the thickness. In this case, dull means good and shiny…not so much.The next time you are in the market for a zinc coated part, remember the differences between zinc plating and zinc galvanizing.
Reply:All be using one for sure. Thanks Originally Posted by hartcreekIn any case he is gonna be picking up crap just to practice on so he should be using a respirator because it will be mixed junk.  Anyone got any suggestions.  All I commonly see are the charcoal nose-mouth masks at my local welding supply place. They have active charcoal and would help a bi and do fit under most hoods..
Reply:Originally Posted by kolotweld on it, you'll figure it out real quick.
Reply:If the steel is non Galvanized it will be shiny and have a consistent color across the whole thing. Galvanized has a noticeable crystal pattern like Teetor described with many color variations i.e. some areas grey looking, some silvery, some almost a yellow tint. It's very distinct, and hard to confuse for regular steel.