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Reticulation is a process by which metal is made to draw itself into ridges and valleys, creating a unique texture. Many alloys can be made to reticulate, but a formulation of 80% silver and 20% copper yields particularly dramatic results. Because copper plays an important role in reticulation, higher copper content generally enhances results. 14K and 18K yellow or pink gold will work better than 14K or 18K green or white. 18K works better than 14K. How To Reticlate 1. Because the process is somewhat unpredictable, work on a piece of metal a little larger than your actual need. Twenty- to 26-gauge sheet will produce the best results. Heat the piece of metal to 1200° F (650° C) and hold at this temperature for five minutes. This is most easily done in a kiln but can be done with a torch (keep the metal at a dull red). Do not use flux since the purpose of this step is to create a layer of copper oxide. Air cool. The metal will be a uniform dark gray. 2. Pickle in hot fresh pickle or a 10% sulfuric acid solution. This removes copper oxide from the surface leaving a silver-rich skin and "locking in" the copper oxide layer beneath. 3. After rinsing, heat as before to the same temperature, this time for at least 10 minutes. Oxygen cannot react much with the silver-rich skin so it penetrates and promotes growth of the copper oxide layer into the sheet (i.e. interior oxidation). Air cool. The sheet should be only slightly gray. Pickle as before. 4. Reticulation is done with a torch. Since it is necessary to make the metal molten throughout its interior, it is wise to either preheat the soldering block and then allow the heat to rise up into the sheet, or to work on a wire mesh. The sheet is brought to red with a sharp hot flame. The torch is quickly passed over an area allowing it to cool intermittently. The cooling is what causes the metal to buckle. The skin may melt and crawl without damaging the results, but this should be minimized since this flowing softens the sharpness of the ridges and diminishes the effect. Allow the piece to lose redness before quenching.
5. Reticulated
metal may be soldered, colored and finished like its original stock.
It is brittle, and extensive forming is not recommended. The copper
oxide layer seems to be porous and "soaks up" solder when
joining an exposed edge. To make a neat and strong joint, burnish the
edges before soldering. © Excerpt from "The Complete Metalsmith" with permission from Tim McCreight. To purchase this book and others, visit Brynmorgan Press. |
