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Want Sticky Patina for Larger Objects

I am making some copper ornaments that I wish to treat and give a green or blue finish. They are too large to submerge in a patina solution or bury in sawdust.

Can anyone suggest a method of making a patina that will stick to the ornament while it is working, but can be washed off when finished? I have thought about mixing in sugar, but I suspect that I will not really work.

I am working in a domestic garage, so will need something that is not too caustic or dangerous and is reasonably easy to obtain.

Thank you.

James.

James Alford
Currently a hobby with a view to selling. - Aylesbury, England
July 15, 2010

Mix patina and corn starch,as patina solution you can try 250 gm ammonium carbonate/250 gm ammonium chloride solution/ 1 lit water(less chloride=more bluish hue/less carbonate more yellowish).If you want more natural look pretreat with liver of sulfur solution(2% is ok).Hope it helps and good luck!

Goran Budija
- Cerovski vrh Croatia
July 19, 2010

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Dear James ,
You can try starch, gelatin, agar agar, calcium sulphate, barium sulphate.
Good luck

Khair Shishani
aircraft maintenance - Al Ain, UAE

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July 20, 2010

Goran,

Thank you for this suggestion. I will give it a try. Can you give any idea of the amount of starch needed? Also, does it all wash off afterwards or do you leave it on?

Thank you.

James.

James Alford
- Bucks, England
July 20, 2010

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July 23, 2010

James

A common way of thickening chemical solutions is to add methyl cellulose - commonly known as wallpaper paste. Avoid the fancy brands. Go for the cheapest and dissolve in your patination solution instead of water.

Geoff Smith
Hampshire, England

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July 28, 2010

I think that it must as thick as honey. Geoff's advice is good too (wallpaper glue). For slower evaporation some glycerine can be added. Try it first on some copper scrap -- hope it helps and good luck!.

Goran Budija
- Cerovski vrh Croatia

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August 1, 2010

Thank you for the suggestions. I shall have a play with both cornflour and paste and see how I get on.

Regards,

James.

James Alford
- England