In article , RainLover
wrote:

On Sat, 04 Sep 2004 09:08:06 GMT, Ernie Leimkuhler
wrote:

In article , RainLover
wrote:

while I'm on a posting roll...

I've used pickling paste on 316L for the last few of my sculptures,
but I've had a disturbing thing happening... While it brightens the
stainless (almost a blue tint) and removes all the little surface rust
spots, it also leaves a coating... almost of a 'smudged' look..

I leave the past on for about 15 to 20 minutes and agitate it with a
nylon brush before rinsing and rubbing (with my rubber gloves on) it
off.

What Am I doing wrong?

Thanks,

James, Seattle (port orchard, Washington, USA, Earth


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.

http://www.stellarsolutions.net/

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.