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Acid gel

I have recently built a welded stainless steel sculpture. It is approximately a metre high and I wish to place some acid gel on a few selected areas ...This is an at home project .My question is regarding the washing off and disposal of the acidic waste. Can someone please advise me of a simple cost effective and environmentally safe way of washing off acid from my sculpture.

Scott Adams
I am a stainless steel sculptor - Atherton, Queensland, Australia
February 2, 2008

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Are you trying to remove the heat discoloration from welding? If so, the gel you are talking about is commonly called "pickling solution" and should be available at local welding suppliers. However, it is EXTREMELY hazardous.

This is typically a blend of Nitric and Hydrofluoric acids. This is a really nasty acid blend that is not only toxic to humans but creates a hazardous waste.

If you have experience handling chemicals, you can capture the rinsewater and raise the pH with lime or a caustic chemical. This will cause the metals to precipitate out into a sludge and leave the water above clear. However, it may still be a hazardouswaste.

Pickling solution will etch the metal and leave it bright but somewhat dull.

Be VERY careful with this solution.

There are electrochemical processes but they aren't commonly available to consumers.

Todd Turner
- El Dorado, Ark.
February 12, 2008