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Copper plate cast iron bench ends using copper sulphate?

2007

I was given a pair of decorative cast iron bench ends, and their green patina suggests they were copper coated. However a number of large rust spots are showing through. I was wondering if I could sandblast them to clean them up, and then sponge on a copper sulphate ⇦this on eBay or Amazon [affil links] solution to re-coat them with copper.

When I was in high school I dipped soft iron transformer core plates into copper sulphate solutions to plate the iron with copper. I recently learned that copper sulphate is used in large quantities by farmers to treat cows' feet. I still haven't found a source of copper sulphate in my area yet, but do you think the idea has enough merit to be worth pursuing?

(I also want to copper plate other things; this is just the start. I like copper. :) )

Thanks.

Owen Lawrence
Hobbyist - Ottawa, Ontario, Canada

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That will work, but the finish is NOT very adherent!
Take it to a plating shop for a professional job. By the way, it is against the law to dump the used copper sulphate.

James Watts
- Navarre, Florida
2007

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Slightly acidified copper sulphate solution can be used as immersion copper plate(add few drops of sulfuric acid).Your object must be grease and oxide free!Hope it helps and good luck!

Goran Budija
- Cerovski vrh Croatia
2007

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Hi Goran,
I do not think that you can get a good immersion finish on cast iron. Possibly if it is freshly grit blasted and well rinsed.

James Watts
- Navarre, Florida
2007

I think that coppering by friction is somewhat better process for cast iron(mix dry tartaric acid ⇦this on eBay or Amazon [affil links] powder with some copper sulphate solution--rub it on object, according to an old german book/Hand und hilfsbuch fuer praktischen metallarbeiter-handbook for metalworker,cca.1900/). Good luck and hope it helps!

Goran Budija
- Cerovski vrh Croatia
2007