removing galvaniziation

[Pault17]

I haven't searched yet, but was wondering if there is a way to remove the zinc from small items by any other means than heat. Or is heating the easiest/fastest/"safest" way.

I have some smallish tubing and things that I have only been able to find in galvanized condition and would like it clean.

any help is appreciated

[habu68]

Before you heat galvanized material (zink) please read: Link removed at the request of anvilfire

I'am sorry if I offend for sending traffic to the "other guys" but that demo was the last by a friend to many smiths and someone I have never met in person, but helped me get started in smithing.

mild acid, viniger,muratic will work but then you have toxic acid. A better choice would be black iron, and skip the galvanized material. IMHO

[Daryl]

Better yet, throw the galvanized material to the scrap dealer and put your time, energy, money and health into finding more appropriate material. In my opinion, the health concerns far outweigh any percieved savings.

[Sam Salvati]

I agree, NO steel is worth risking your life over, especially not some galvy coated scrap bits. Drop it off at the scrap yard, and ask him for some springs, I swear you'll be happier!

[Glenn]

Habu there is no problem with the reference.

What is NOT mentioned is that Jim Wilson had COPD and his breathing was compromised already. Zinc Dangers this is a reference to a earlier topic on IForgeIron concerning Zinc.

Chronic obstructive pulmonary disease (COPD) is a term used to describe two related lung diseases: chronic bronchitis and emphysema. Chronic bronchitis is inflammation and eventual scarring of the bronchi (airway tubes). Emphysema is enlargement and destruction of the alveoli (air sacs) within the lungs. Many persons with COPD have both of these conditions.

Persons with COPD have difficulty breathing because they develop smaller air passageways and have partially destroyed alveoli. The air passageways also become clogged with mucus, a slimy substance.

JAMA Patient Page - Archives and Journals
http://www.medem.com/medlb/article_d...&sub_ca t=571

[johnny99]

Paul, the easiest way, is to use murriatic acid. about three bucks for a gallon. use a five gallon bucket w/lid and mix one to one with water. ( remember, acid into water. Not water into acid when mixing). Just submege your small parts for a couple of minutes and it will disolve off all of the galvi. Make sure to do it outside as it does produce fumes. It will become weeker with use. WHen it stops working, neutralize w/baking soda.

[Ten Hammers]

There are all kinds of ways to do this. The SMARTEST way is to buy black pipe. Jim Wilson was a friend of mine.

[Sam Salvati]

FOrgive the mini rant, but what is this OBSESSION with wanting to get, and remove galvy instead of JUST getting the right stuff, or waitng a little longer to find the right stuff!??!?!??!?! WHY!??!? It is JUST NOT WORTH IT, unless it is like a brick of gold covered in galvy, then DON"T WASTE THE TIME, ENERGY, EXPENSE, AND RISK OF DEATH OR SICKNESS, SHeesh. WHY BOTHER?

[Pault17]

Thanks to all! I chatted this over with my wife and decided never to work with the silver.
Now just to find what I normally work and make it do.

thanks again

[Glenn]

I chatted this over with my wife and decided never to work with the silver.

Think you mean galvanized.

Try to avoid all zinc coated (galvanized) materials, heavy metal poisoning is not fun. And it is not just the fumes, the dust (grinding, sanding etc) can get to you also.

[Pault17]

Thanks for the clarification Glenn. I should have put " " around the silver. My wife and children (we just had our #8) all know that I (1) work with steel and iron and (2) there is the black or rusty (good) or the "silver" a,a galvanized (bad).

I did not know or had not read that the zinc dust was bad as well. I will keep that in mind. thanks again

[rusty_iron]

Gday Paul,

I had a similar problem of removing Gal from steel. I used Phosphoric acid -its what i had -, thats the acid thats used to eat rust in ruster converter, its also found in food and soft drink or as you seppo's call it pop.

I asked a friends father who used to run a galvanizing works. He said use Hydrocloric acid, thats the stuff you put in your swimming pool. Interestingly, he said that the solution thats left can be used as flux for soldering. I have not tried this.

As to the comment on not using gal material and waiting for black iron to turn up, well sometimes its just not available or too expensive. I was building burners for a gas forge. Initally black iron pipe fittings were not available here in Australia, only the gal fittings. When I did eventually find them the price was too high, gal bell fittings were about $4 and the black iron was over $30 each. Thats what you get when there is only one supplier.

Etching the gal off was the only reasonable option, and seemed to work quite well. Oh don't light a match or smoke near the etching process, if I remember correctly it probably produces hydrogen which will burn.

Have fun,
Rusty_iron
Brisbane, Australia.

[Pault17]

Thanks Rusty. glad to hear from you!
I have family on your continent.

[Ted T]

Pault17,
My advice and my vote would be to

[habu68]

Ted

Amen and God Bless

As my Great Grandmother said. "Too soon old, Too late wise"

[frogvalley]

I respect PawPaw and the work he did, many of us were sad to hear of his passing. However he made a bad choice in the method of removal of these coatings. Way too much at once. Burning is OK sometimes, but not in the concentration that he did.

I know I am stirring a hornets nest with this one.

My shop is a multi faceted business, mostly art metal, sometimes there is no way around working with the stuff. At times we CHOOSE to make something from it for the anti-corrosion properties. We weld it with mig or even tig for minimal heat affected area, therefore less outgassing or burning of coatings. Top coat with zinc paints.

Working with galvanized materials is not nearly as dangerous as is claimed. Work in a well ventilated area. Don't eat it or breath a lung full. Long term exposure to other materials commonly found in welding rods is more of a danger. Think chromium, vanadium, etc.

Zinc oxide is what they put in your sunscreen, other health products and breakfast cereal to make it whiter and more yummy. In smaller doses it can be beneficial, zinc is a mineral commonly found in Vitamin supplements.

Toxic levels are so much higher than you are normally exposed to in a well ventilated shop, that working with care on galvy is not a danger and I do it frequently without reservation. Not to mention the fact that eventually the zinc will dissipate from your system with generally a full recovery from the symptoms.

And I ain't gone mental or died yet. Well not that I know of anyway...

[Ted T]

Pault17,
As you can see there are several opinions about the safety issues with working with Galvanized material. That is why we are fortunate to have the IFI platform to facilitate us to lay issues out in the open and learn from each other.
As you see, some opinions indicate galvanized material can be worked with safely.
I am convinced you can work with galvanized material safely. But, you would have to be sure you know exactly what you are doing with out question.
When I wrote the first reply, I was trying to keep it short as possible. But I think I need to say a little more about who may be effected by galvanize and other hazardous fumes.
Ref: An old doctor who treated people who worked in the ARMS Plants during the 2nd world war learned a lot about the effects of toxic fumes. He had a large population of welders that he treated to learn from.

He said that some people cannot process the effects of toxic fumes as well as others.

Meaning, Joe may not have problems with it, But Sam may have difficult problems with it while under the same exposure level. This is just another factor to consider in the equation.
I certainly appreciate all the opinions voiced on IFI. I learn more and more all the time.
Be safe!
Old Rusty Ted

[one_rod]

Without wanting to step into the middle of the "should I/shouldn't I" debate:

I work at a metal treatment plant where we put zinc coatings onto metal. The process sometimes goes wrong and we have to take it back off again. So, a few practical tips for anyone wanting to strip zinc safely. Some of this information has already been mentioned in this thread, but it stands repeating.

1. Use Hydrochloric Acid. Use it fairly dilute and at room temperature. Don't use strong acid, don't heat it up.

2. Never, ever attempt to burn off zinc coatings.

3. Many zinc plated items have a laquer or varnish applied to keep the finish shiny. This will slow down or stop the acid from working. A rub with a wire brush or coarse sandpaper will break it up enough to let the acid work.

4. Work outdoors or with good ventilation. Hydrogen gas is generated, it's inflamable, explosive and besides, the whole process stinks!

5. To tell if all the zinc has gone, wipe the metal with a weak solution of Copper Sulphate on a rag. Bare steel will instantly turn reddish brown or black, remaining coated areas will not.

6. Be very carefull with pipes and tubular items. The process generates a lot of gas and this will find it's way out of the open end of tubes, taking the acid with it. I have seen foaming "acid fountains" six feet high from the end of galvanized pipes in stripping tanks. Not fun.

7. The spent residues from the process (mostly Zinc Chloride) do make exellent brazing flux. But because of the dissolved toxic metal content it would be illegal in most countries to empty it into public sewers. So don't get caught.

one_rod.

[Pault17]

All,
thank you all very much for the multiple facets of the safety and danger of working with zinc. a year and a half ago when I first started actively "bangin iron", I discovered anvilfire. I read through pretty much the whole site. I paid very close attention to the write-up on paw-paw's passing and the reasoning of and behind it. That is the one thing above all others that kept, and still keeps, me from having any real desire of working with anything to do with zinc or galvanization.

Because I am working on a new, slightly larger forge (my orignal 'bean can' forges are just too small for where I am progressing) one of the components is a means of securing my new torch (rex price shorty). I had been unable to locate a piece of tubing or pipe large enough to let me slide the torch into, other than a piece of galvanized nipple. When I first fired up the forge, after getting my gas lines and fittings to stop blowing soap bubbles, I saw a small amount of whitish smoke coming from the top of the nipple and instantly shut everything down and asked the question that started this whole thing.

I am now looking for a different material to use, and will have to continue using my bean can for a while longer. My wife and children are worth the wait, and I am constantly praying for patience.

Again, thank you all for the knowledge and for not calling me an idiot.
Glenn, thanks again for your help and for keeping such a wonderful site up and running.

[Glenn]

Why not post a request for the parts needed in the tailgating section of IForgeIron. I am sure that someone somewhere can locate the piece of metal you want and can ship it to you.

[Mark Parkinson]

pault17 :
what size and length of pipe do you need? I do have a good stock of black pipe cut offs. I would be glad to send you the piece you need

Mark

p.s did yo use pipe dope on the threads it burns with a "white steam" look to it if you manage to get it in contact with a hot surface.

[Pault17]

Mark,
thanks for the offer. the tubing is 1.25 ID piping only about 3-4 inches long. I have had my piece soaking in vinegar since I started this whole thread and the galv is almost all gone. I have changed out the vinegar three times so far just to keep it fresh. The waste I dilute heavily with water and water the woods with it. nothing has died yet and the tube rusts up almost completely in just a few hours. When it all rusts up, I will blue the whole thing and run with it.

Here are a few shots or where it is being used. there is no dope anywhere near the burner mount, other than on the burner supply. The smoke that did come out was almost like teflon tape in solid thickness (no other way to describe it). As soon as I saw it, I shut everything down. I always have the garage door open partway for ventilation as well.





If this doesn't work, I will be getting in touch with you again to discuss shipping. many thanks, again
paul