Guest Editorial -For Plateworld.com                                                 

 Don Baudrand, Don Baudrand Consulting,   e-mail:donwb@tscnet.com

 

Doís & Doníts of plating onto non-conductors

 

Some people would like to plate onto art objects, flowers, or perhaps even baby shoes. Others would like to plate onto ceramic for use in the electronics industry, or for other reasons that may be functional or decorative. Silver and gold are popular with both decretive and electronic applications. Here are a few methods used for these purposes. Letís start with flowers. Roses are popular items, be wary of thorns. Other flowers lend themselves to decorative plating.

Flowers

  1. Clean the flowers to remove dirt, sticky substances using a mild cleaner such as dishwashing detergent. For oils that are heavier, a mild alkaline cleaner such as "Spic & Span" or equivalent. (Pardon the trade name see below) these contain sodium carbonate and surfactants.
  2. Rinse thoroughly, then immerse in a very mild acid such as 5% hydrochloric acid, or 6% phosphoric acid. Agitate mildly then rinse well.
  3. Immerse in a solution of stannous chloride (tin chloride) 10 g/L and Hydrochloric acid 40 ml/L. 1- 2 minutes. Then rinse Preferably in DI or distilled water.
  4. Immerse in the catalyst solution- palladium chloride 0.2 g/L 1 minute, then rinse.
  5. Electroless copper plate. Solution A: Rochelle salt 170 g/L, Sodium hydroxilde 50 g/L, copper sulfate 35 g/L sodium carbonate 30 g/L and Versene-T or EDTA 20g/L. Solution B: formaldehyde, 37% by wt. Mix A and B solutions just before you are ready to plate. This produces a uniform thin layer of copper.
  6. Electroplate copper, starting with low current density, gradually increasing to 15-15 amps/sq ft. to desired thickness.
  7. Electroplate bright nickel to at least .0003" or more. This takes 10 to 30 minutes depending on current density.
  8. Gold or silver plate to desired thickness. Current density 2-3 amps/sq ft.
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