The authoritative public forum
  for Metal Finishing since 1989
-----

Process to color low lead brass parts bright transparent green or blue

Hi my name is Christopher, I'm looking for a production process or formula that can color low lead brass a bright transparent green or blue, or solid green or blue color (not an old patina look). A potential client has asked that we color these parts to somewhat match their assembled products. Painting or powder coating is not an option. The parts are small, not sculptures, and would be clean prior to the process. The coating once applied needs to be safe for the environment, RoHS compliant and not flake off (Something like an inert dye finish would be great). I would also appreciate a comment, if you know, on the disposal of the chemicals in the process.

Any help would be great.

Christopher Haczynski
Product Design - Oak Forest, IL, USA
July 13, 2009

---

Try lustre colours formula(240 gr sodium thiosulphate ⇦this on eBay or Amazon [affil links] /30 gr citric acid ⇦this on eBay or Amazon [affil links] /25 gr copper acetate [affil links]/1 lit water-immerse objects in solution(16 C temp.,20-300 minutes)-colour sequence purple red-peacock blue-lime green-pale gold-petunie-green-lime green-green gold-strawberry-green brown-reddish grey-grey).Hope it helps and good luck!
According to D.Fishlock:Metal Colouring,Teddington 1962.

Goran Budija
- Cerovski vrh Croatia
July 25, 2009