Removing zinc/cadmium plating?

Zinc comes right off with muratic (HCL) acid. The steel will rust immediately if you don't take steps to prevent that. Makes nasty fumes, do it outside and stand upwind.

Karl

Very easy. Go to the supermarket where they sell cleaners and find a can of Red Devil lye. That's about a pound give or take. Add it to about four gallons of water and drop your parts in overnight. The zinc will be entirely gone and if there was any rust on the steel that will be gone too. You can certainly use acid but I don't like to use acid for this because the acid eats the steel too and you have to really worry about neutralizing it. The lye doesn't eat the steel so if you leave it in too long it doesn't hurt anything, plus the rust gets chemically reduced back to iron, not eaten away.

It's nice if you neutralize the chemical before disposing of it. Don't dump it into a storm sewer, make sure it finds its way to a sewer treatment plant.

I have done this myself, recently, worked perfectly. Be aware that whether you use a base (lye) or an acid (e.g. muriatic) one splash can blind you, so wear goggles, use good chemical proof gloves, and wear old clothes, and don't do this anywhere near where animals or small children go.

GWE

Just checking, that is sodium hydroxide? I'm in the UK and I don't think we have that brand here (though we do have a "Red Devil" brand of small power tools, vaccuum cleaners and the like).

I had wondered whether NaOH would work on zinc, and I agree that it would be better for not eating the steel. I'll give it a try. Thanks.

In the USA, yes, it is.

Here, those are Dirt Devil, but yes they're red.

Once you fill that lye solution with zinc and cadmium salts it ain't supposed to go down the drain, at least not anywhere in the states.

Fair 'nuff, but every bit of galvanized hardware in the US is leaching off zinc. Slowly, but it adds up. Compared to this, a few grams from home ain't peanuts. You're correct, of course. So suppose you dissolve some zinc into NaOH and then neutralize it perfectly with muriatic (HCl) getting water, zinc and salt. What do you suggest doing with this if you want to be environmentally correct?

GWE

I guess they'd better stop selling chemical drain cleaners where there's bound to be galvanized drain pipes!

Ken Grunke

Zinc isn't the problem.

Steve

Then what is? - GWE

Cadmium is nice and poisonous.

Ya know, I wonder if cadmiate exists -- it's pretty similar to zinc after all. If not then you'll have to use acid to strip any cadmium.

Tim

-- "I've got more trophies than Wayne Gretsky and the Pope combined!" - Homer Simpson Website @

It does.

But what to do with the residue?

The cadmium used came from somewhere, presumably a mineral deposit. We played with it, and discovered it isn't a nice thing to play with. I guess we should put it back where it came from?

Anyone got any ideas how to do that?

Now do the same with the extra carbon, as in oil or coal ...

-- Peter Fairbrother

"And you're not a gun freak?"

"Oh no. I'm a collector. Huge difference."

"The difference being?"

"I've got more guns." :)

It makes NiCd batterties work. too pissweedd loe ya all grvmawlduj; jc2js, oooooh yeea;aodfhhhhhhhh mbsxdjlzs

-- Peter Fairbrother

When I see you floating down the gutter I'll buy you a bottle of wine.

The beautiful rainbow colored bolts and nuts used (on motorcycles, etc) is Cadmium. Don't work on the cycle and then stick the finger in your mouth...

If counting those in a box - wear gloves and hasmat them afterwards.

Mart> Peter Fairbrother wrote:

Only place I've run across much cadmium is working on WWII era electronics. Many metals were in very short supply in those days including zinc, so cadmium was pressed into service "in a pinch". Guess I'm lucky. - GWE

Ain't it oxidized to a dusty yellow after many years? I've seen that on old (50s) stereos and speakers before...

Tim

-- "I've got more trophies than Wayne Gretsky and the Pope combined!" - Homer Simpson Website @

Yup. That's the stuff. - GWE