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Restoring copper contacts

2004

I am trying to revive the Kodak Brownie Starmite camera, that my parents gave me for my 9th birthday, 43 years ago. Unfortunately, I found that the two AA batteries have leaked badly during years of storage and all the copper connections are covered with a thick crust of bright blue copper sulphate ⇦this on eBay or Amazon [affil links] crystals surrounded by white crystals (don't know what that could be). I have scraped off most of it, but I wonder if there is some process (electrolytic or chemical) by which I could restore the copper to its former appearance, or at least get the contacts to work again.

Thanks and regards,

Barend Jan van Spaendonck
- Amsterdam, The Netherlands

To restore function, a small stainless steel brush does the job. Here in the States they are found at some of the electronic supply stores sold as 'soldering aids'. If the batteries were ordinary carbon-zinc (Lelanche) cells, the electrolyte that leaked out and caused the corrosion is a mix of ammonium chloride, zinc chloride, and carbon. Perhaps someone on this site that knows more chemistry can help from here.

Tom Gallant
- Long Beach, California, USA
2004