Metal finishing Q&As since 1989

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Stripping brass plating from aluminum or zinc

We regularly powder coat small brass plated lamp parts. The plating often lifts during the cure cycle, causing rejects. Our sandblast medium is too aggressive. Is it possible to reverse-plate brass from aluminum or zinc? Thanks in advance!

Curt Emerich
Powder coating - Bozeman, Montana, USA
2006

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Best to fix the plating problem. Maybe post your base alloys and the complete plating procedures for each.

Brass as well as most other metals can be stripped from aluminum using nitric acid. Use 50-100 vol.% of technical grade nitric (the stronger the nitric the better for the aluminum), with good ventilation and a tight lid when not in use. Add a little concentrated hydrogen peroxide to prevent noxious reddish NOx fumes.

Concentrated nitric acid also works for stripping from zinc substrates, but adding (very much) water causes attack of the zinc. Try a proprietary stripper from a 'Chemicals & Perishables' supplier below.

Ken Vlach [deceased]
- Goleta, California
Finishing.com honored Ken for his countless carefully researched responses. He passed away May 14, 2015.
Rest in peace, Ken. Thank you for your hard work which the finishing world, and we at finishing.com, continue to benefit from.
2006