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Picture of Remove Galvanization
Galvanization is the process in which steel or another metal is coated in zinc to stop the base metal from oxidizing. In this instructable I will tell how to remove this coating of zinc. Some people may be wondering why you would want to do this. Well, when galvanized metal is welded it gives off toxic fumes that can be harmful.

(NOTE: I apologize for the poor image quality)
 
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Step 1: Supplies

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for this instructable you will need:

vinegar

a wire brush

a small glass bowl

a small flashlight (optional) 

Step 2: Soak it

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First, fill your bowl with vinegar, then put in the piece of metal from which you want to remove the zinc. Its that simple. It took about half an hour to remove the zinc from a screw about 4 cm. After a short period of time bubbles should appear on the surface of the vinegar and there should be small semitransparent lumps that come off the piece of metal. I used a glass bowl so I could shine the flashlight through the vinegar  to see the bubbles and the lumps better, but this is optional.

Step 3: Brush it

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After the half hour has passed, take out the piece of no-longer-galvanized metal. Once you take it out, rinse it under cool water and scrape it with your wire brush. After you have brushed all over the metal, rinse it off again and its safe to weld it.

NOTE: Because screws have threads I would not recommend using them, they take longer than rods or another shape that doesn't have threads.
OisinL111 days ago

How do I dispose of the residue? I'm using HCl and baking soda to neutralise. Where can I dump to solution that is left over?

This does work really quickly though and the foam is easy to remove.

StevenS57 months ago

i am welding 18 12 14 16 gage sheet galvinized metal in the a c plenum bisseness how would i clean the zinc coting off of it. and why did the company that i work for not tell me how dangerus it was to weld galvinized metal.i have been welding now for 12 years now and have had 2 hartatacts do this have any thing to do with my helth in general. we use fans to blow the fums away is there any other thing i can do to protect my lungs from the fums. my gmail addres stevensweeney92@gmail.com

RichardW59 months ago
Awesome info. Thanks
aeray4 years ago
Hydrochloric acid (muriatic acid, available at hardware stores) works well too. And very quickly.
tranoxx (author)  aeray4 years ago
it probably does but this is cheap and can be done with supplies found around the house
aeray tranoxx4 years ago
Hydrochloric makes NASTY fumes too, so I'm sure your method is safer as well.
In addition to those fumes, it also makes hydrogen gas. Dangerous, but fun.
dratman bombmaker210 months ago

I think vinegar would make hydrogen gas too.

tranoxx (author)  bombmaker24 years ago
yeah but mostly fun
Oh so true.
Surely not buying galvanized screws would be less effort ;-p good idea though...
tranoxx (author)  killerjackalope4 years ago
well yes but i dont have access to ugalvanized screws or bar
check the phone book or look for weld shops we use bare steel all the time.
unplated screws are hard to find but you can if you look.
Dr Qui tranoxx4 years ago
I find that statement extremely hard to believe.
SCKStef4 years ago
Nice method,

But This method only Works for Small Objects wich are not Fire galvanised...and the Most of the time you have to weld pieces wich are Fire galvanised.

Fire galvanised iron have the Most of the Time an too thick Zünd overlay from 0,10 to 0,50 mm and more on the edges.
aeray SCKStef4 years ago
"fire galvanized" = hot-dipped galvanized, I believe.
tranoxx (author)  aeray4 years ago
that clears things up thanks