Pickling Paste on stainless steel: WHITE HAZE WON'T COME OFF

Sorry I cant give an answer to your question about the smudging, but please be super careful with that pickling paste. It may contain hydro-fluoric acid which is shocking stuff if you get it on your skin. Look up the material saftey notes on it. Please be careful with it.

Sorry to sound like a worry wart but I'd hate someone to loose fingers simply because they didn't know how bad this stuff can be.

Dean.

Fingers hell... According to what I've heard/read over the years, spilling hydroflouric acid on your fingertips equals "We're going to need to take your arm off at the shoulder - Just to be sure."

It's even worse than you think. If it gets inside of you it will literally attack you from the inside out. You don't even have to get in your mouth or breath it. It will absorb through the skin. I knew a guy years ago working in a plant that used hydrofluoric acid for electropolishing metals. He accidentally tripped and managed to step into an open shallow vat of it. Got only up to his ankles as I recall. They didn't stop the absorption fast enough and it got inside of him. Literally corroded him from the inside out. Attacked his bones in particular. Took him a few days to die. What a bloody horrible way to go. Made me sick to my stomach when I heard what had happened to him. If this pickling material does contain HF then be VERY careful. There is a special cream you can get if you are working with HF. I think it's calcium gluconate. If you get any HF on you get this cream on the affected area ASAP.

Nothing. The acid is just etching the surface (that's what pickling is supposed to do). If you want it shiny, you'll have to polish it after pickling.

Gary

HI Dean...Thanks for the warning... I know how nasty Hydo-fluoric acid is and it DOES contain it, along with some other nasties. I wear a full organic facemask/filter, long sleeves, chemical gloves and have a hose right next to me in case of accident.

It's the "worry warts" that have all their eyes and ears and skin when they retire.....

James, Seattle

Hm... that's too bad. I put a 'texture' into the stainless steel so any other machining would destroy it... any idea how I could pickle it AND have it be shiny afterwards?

James, Seattle

electropolishing seems to be the only way, but i think it will remove about

Would some type of blast media satisfy your needs?

Bob S.

Hi James. Besides all the warnings about the hazards of Hydrofluoric Acid, I thought I might help you a little.

The haze is usually where you have etched the metal. If the haze refuses to come off with a mechanical process, like a wire wheel on a grinder, then I wonder if you are making the mistake of puting it on when the metal is still hot . Always wait until he metal is cold to the touch.

I went to Citric Acid Passivation 2 years ago and have never regretted it. No toxic chemicals and it works very fast.

If you are intertested you can come by my shop in Renton and I can demo it for you, or maybe you can lure me out to your shop finally.

I can usually be bribed with food and gas money.

The stuff I use is type 9002 Citrisurf

You can check it out here.

Hi Ernie,

I've been wanting to get out to your place for over a year now... I really need to. I looked at teh Citrisurf web site and it looks like the stainless needs to be put into a hot bath of the product, is that the case? it would be difficult for me to make a tank that would accomodate my sculpture since every one is a different (and large) size.

How do you do it? I like the brush application of the Hydrofluoric Paste, but I definately don't like the acid itself!

Thanks, James, Port Orchard

I use Electro-passivation. I apply the citrisurf with a wand that is connected to one side of a 36 volt DC power source. The other side is grounded to the piece. The paste carries the electrical current which catalizes the citric acid. It is extremely fast and very non-toxic.

On Sun, 05 Sep 2004 22:57:25 GMT, Ernie Leimkuhler calmly ranted:

Does it leave a pristine surface, no "brush marks"?

========================================================== CAUTION: Do NOT look directly into laser with remaining eyeball! ==========================================================

Ernie Leimkuhler wrote: [pickling]

Can you describe the wand? Is it just a metal rod or does it have a conductive (carbon?) brush? (I mean brush in the paint, rather than DC motor, sense)

Tim

No brush marks. If you leave the wand in one spot too long you can etch the surface.

It works very well for removing oxidation colors from brushed stainless without harming the brushed surface.