Preserved Flowers - Wyatt Arnold

Electroplating: The process of depositing a thin coating of a metal onto another metal by passing a current through an electrolytic cell.

Electroforming: An electrodeposition process for depositing a coating of metal onto a non-conductive or minimally conductive object through the application of a conductive coating.

The Promise of Electroforming

For a while, I had been interested in electrolysis, both for plating and the possibility of electrolytic cleaning, techniques that seemed like they could be useful when restoring antique parts and machinery, something I’d occasionally find myself doing. However, I never got around to it until I stumbled upon a related process: electroforming.

Electroforming, while originally conceived as a means to produce thin, difficult-to-machine parts via the deposition of a metal onto a mandrel, which acts like a mold (left), has been co-opted by the art world as a technique to produce metal replicas of organic objects (e.g. a leaf). When I ran across a few images of what the method can produce, I immediately had to try it.

A Case Study

Electroforming requires just a few components: 1.) plating fluid (a mixture of sulfuric acid, copper sulfate, and brightener), 2.) a copper anode, 3.) a plastic or glass container, 4.) a DC power supply, and 5.) conductive paint (either silver or graphite-based).

After getting the system up-and-running, the workflow, as demonstrated with a few Oncidium orchid flowers, looks a bit like the following:

For objects that are delicate, porous, or may resist the conductive coating (e.g. a waxy cuticle), an initial coating of sealant, in this case lacquer, is applied to improve the final product.

Following a dip in the lacquer can, the object is allowed to dry completely before receiving the conductive paint. Solvents off-gassing while electroforming can create issues in the finish.

The conductive coating (a thin, graphite-based paint) can then be applied.

For delicate objects, an airbrush is perfect for applying light, successive coats.

The finished coating.

After the object has been sealed and coated, it’s then into the electroforming bath, for anywhere from 12-24+ hours. The object being electroformed becomes the cathode, and thus serves as the site for the reduction of copper ions to copper metal. The copper ions in the bath are constantly being replenished by oxidation of the consumable anode.

In my setup, the anode consists of a length of coiled 1/4″ copper refrigerator line, which is sheathed in a tube of non-woven polypropylene in effort to limit the transfer of any copper particulates from the oxidation, and thus corrosion, of the anode. If the anode is not covered, the finish on the final electroformed piece will be less uniform and more crystalline.

After the piece is immersed in the bath, copper, appearing white due to the blue color of the bath, can be seen covering the stem of the flower.

A few minutes later, and the deposition of the copper has progressed further down the stems and toward the flowers.

After the piece has electroformed for a sufficient amount of time, clean-up is simple, and involves simply rinsing the object and neutralizing any remaining acid. The finished piece can be seen below (upper left), as well as a host of other electroformed piece.