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Zinc on metal question

Posted: Sun Mar 01, 2015 7:04 pm
by Hvacr
New welder here and i would like to practice on some thin (about 16 gauge) metal that appears to have a zinc coating. Can i clean this zinc off with something (acid solution?) in order to protect myself from zinc fumes? :shock:

Re: Zinc on metal question

Posted: Sun Mar 01, 2015 7:10 pm
by rick9345
Don't
Zinc and Tig does not dance well together. Not good place to start for beginner.
The cleaner what ever metal you start with the easier the learning curve.
3/16 - 1/8 nice thickness to start out on.

Re: Zinc on metal question

Posted: Mon Mar 02, 2015 7:22 am
by Hvacr
Rick9345, what i was thinging of doing to get some practice laying some beads was to double or triple these sheets up tack weld them together and practice laying some beads down. I have a lot of this type of scrap around but did not know if it would be safe to use it like i want to. Will this be ok?

Re: Zinc on metal question

Posted: Mon Mar 02, 2015 7:55 am
by weldin mike 27
You'll have a hard time getting productive practice on galvanized or coated metals. You need to be able to see the puddle, but with zinc burning off everywhere, and popping, it's a waste of time.

Re: Zinc on metal question

Posted: Mon Mar 02, 2015 8:07 am
by Hvacr
Ok, good to know. I will get scrap mild steel. What i was unsure of is whether i could somehow remove the zinc first. I have looked up zinc and gone to several sites and found different and sometimes differing info. About zinc, some say it becomes part of the metal itself and cant be fully removed and other sites say to use acid to remove it. Since i have a lot of this stuff i thought i would try to find the answer from actual welders. Thanks for your response i'll just get some steel scrap and go from there.

Re: Zinc on metal question

Posted: Mon Mar 02, 2015 2:06 pm
by weldin mike 27
It's one of those things that are really great for what they do, as in corrosion protection. But a pain in the butt for others, such as painting and welding. I believe you can't really get rid of it with grinding or sanding, so for practice, it's not worth it. As for acids, that opens up a whole can of worms you don't need to worry about just yet. Go the plain steel and go mad on it.

Re: Zinc on metal question

Posted: Mon Mar 02, 2015 2:38 pm
by Hvacr
Weldin mike 27, thanks again. That is what i will do, wish me luck and decent beginners technique!

Re: Zinc on metal question

Posted: Mon Mar 02, 2015 2:52 pm
by weldin mike 27
No worries man. Beginning is hard enough without worrying about anything contaminating your weld.

Re: Zinc on metal question

Posted: Tue Mar 03, 2015 8:25 pm
by rick9345
Don't forget
ZINC and welding = toxic fumes

Re: Zinc on metal question

Posted: Tue Mar 03, 2015 9:04 pm
by weldin mike 27
Toxic is a bit extreme. They are not good for you, and you should be careful, but don't be scared.

Re: Zinc on metal question

Posted: Wed Mar 04, 2015 7:56 pm
by rick9345
weldin mike 27 wrote:Toxic is a bit extreme. They are not good for you, and you should be careful, but don't be scared.
If not toxic damm close
http://dictionary.reference.com/browse/toxic

http://en.wikipedia.org/wiki/Metal_fume_fever

Re: Zinc on metal question

Posted: Wed Mar 04, 2015 9:31 pm
by weldin mike 27
I never said it was nice, but When people say toxic, phosgene comes mind. The will kill or at very least ruin your body permanently, in very small doses. So the thing is, be alert, prepared not alarmed. End of story.

Re: Zinc on metal question

Posted: Thu Mar 05, 2015 12:24 pm
by danielbuck
It would be a little difficult to do this for sheet metal, but for zinc plated hardware (nuts, bolts, washers, hinges, whatever) I soak them in citric acid for an hour or two (overnight if I can), that gets them down to bare metal, or really close to it anyway.

I like Citric acid because you don't have to use gloves or anything, and you can dump it down the drain after you're done with it (keep it around after the first batch though, it's good for quite a few batches!). It's very safe. It comes in a powder, just mix it with some water. You may be able to find it at some grocery stores, I had to go to a restaurant supply store to find it locally, grocery stores near me didn't carry it.

Vinegar will work in a pinch, but you'll have to wait alot longer for it to work.

Re: Zinc on metal question

Posted: Fri Mar 06, 2015 8:04 am
by Hvacr
weldin mike 27 wrote:Toxic is a bit extreme. They are not good for you, and you should be careful, but don't be scared.
Ok i will be respectful but not scared. Hey Weldin mike 27 do you think a Chinese inverter stick welder (Klutch ST 80i from Northern Tool) that tops out at 75 to 80 amps is a big enough machine to do beads on a 3/16" mild steel pad with 6011 or 6013 rod, 3/32" and 5/64" respectively. I posted some pics under Stick Welding of the first beads i tried to run, they are abysmal. I watched Jody's stick welding video about different sticks and some of their applications and noted he was using any where from 130 to 150 amps for his beads. The idiot sheet that came with the welder said it would weld up to 3/16" mild steel with 6013. Any thoughts?

Re: Zinc on metal question

Posted: Fri Mar 06, 2015 4:41 pm
by weldin mike 27
It'll be limited in what you can do. Try to find some 1/16 stick rods and you'll be a lot happier. Jody has a video on them.

Re: Zinc on metal question

Posted: Fri Mar 06, 2015 4:48 pm
by weldin mike 27
http://solutions.3m.com.au/wps/portal/3 ... 5KWZ3644bl get yourself one of these respirator kits and you'll be just fine.

Re: Zinc on metal question

Posted: Fri Mar 06, 2015 7:07 pm
by Hvacr
danielbuck wrote:It would be a little difficult to do this for sheet metal, but for zinc plated hardware (nuts, bolts, washers, hinges, whatever) I soak them in citric acid for an hour or two (overnight if I can), that gets them down to bare metal, or really close to it anyway.

I like Citric acid because you don't have to use gloves or anything, and you can dump it down the drain after you're done with it (keep it around after the first batch though, it's good for quite a few batches!). It's very safe. It comes in a powder, just mix it with some water. You may be able to find it at some grocery stores, I had to go to a restaurant supply store to find it locally, grocery stores near me didn't carry it.

Vinegar will work in a pinch, but you'll have to wait alot longer for it to work.
Thanks for the tip!

Re: Zinc on metal question

Posted: Fri Mar 06, 2015 7:11 pm
by Hvacr
weldin mike 27 wrote:http://solutions.3m.com.au/wps/portal/3 ... 5KWZ3644bl get yourself one of these respirator kits and you'll be just fine.
Excellent, and i will try the rod you mentioned. Thanks.

Re: Zinc on metal question

Posted: Fri Mar 06, 2015 7:13 pm
by Hvacr
rick9345 wrote:
weldin mike 27 wrote:Toxic is a bit extreme. They are not good for you, and you should be careful, but don't be scared.
If not toxic damm close
http://dictionary.reference.com/browse/toxic

http://en.wikipedia.org/wiki/Metal_fume_fever
Point taken, respirator and plenty of caution will help.

Re: Zinc on metal question

Posted: Fri Mar 06, 2015 10:17 pm
by weldin mike 27
No problem

Re: Zinc on metal question

Posted: Mon Mar 09, 2015 11:18 am
by cornmuse
I tried tigging galvanized early on (practice on scrap!) Difficult to weld, crappy weld, and, a wicked headache. Definitly the wrong way to learn.
-c-

Re: Zinc on metal question

Posted: Mon Mar 09, 2015 11:56 am
by Hvacr
cornmuse wrote:I tried tigging galvanized early on (practice on scrap!) Difficult to weld, crappy weld, and, a wicked headache. Definitly the wrong way to learn.
-c-
Cornmuse, ok thanks for saving me even more headaches! I got some mild steel i am practicing with, the practice with zinc is on hold. 8-)

Re: Zinc on metal question

Posted: Mon Mar 09, 2015 4:06 pm
by weldin mike 27
By the way, when the time comes that you have to weld gal, mig does a good job as does stick. Some companies use silicon bronze mig wire, as it uses less heat and melts of less of the coating.

Re: Zinc on metal question

Posted: Mon Mar 09, 2015 5:21 pm
by motox
mike
is flux core better for galvanized?
craig

Re: Zinc on metal question

Posted: Mon Mar 09, 2015 5:51 pm
by weldin mike 27
Dunno man. Never done It. The idea of wire welding is that you can do a very small weld in a small amount of time, so it would probably be similar