Forging is an ancient metalsmithing technique used to control the shape of sterling silver and other nonferrous metals by hitting the silver with a specially shaped hammer called a forging hammer. Forging allows the metalsmith to create graceful jewelry and objects that move from thick to thin sections. Forging techniques have changed little since early man. You can find many examples of sterling forged jewelry in museums around the world.
Forging a Taper
Create a tapered surface by placing a sterling silver rod on an anvil and hitting the rod with a highly polished forging hammer. Strike a series of blows down the sterling, starting at the top of the rod. Strike again with a second series of blows, this time beginning lower down on the surface of the rod. Continue to hit the silver until it has moved into the shape you want. Use a planishing hammer to hammer out any bumps. Rotate the rod as you plannish until the sterling silver surface is smooth. The word plannishing comes from the latin word "planus," which means to level or flatten out. Plannishing hammers must have very smooth, highly polished surfaces.
Double-Sided Forging
Place the sterling silver to be forged on a curved surface, such as the curve of an anvil or a sinusoidal stake. Strike the sterling rod with a forging hammer to force the silver to flow in the shape of the curve.
Anneal Frequently
Stop and anneal the metal frequently. Annealing is the process of heating the silver with a torch or kiln to reduce the internal stress in the silver caused by forging. Silver will become hard and brittle as you forge. Failure to stop and anneal may cause your sterling silver to crack and break. Use a torch to heat the sterling silver until it turns a cherry red, the annealing temperature. Allow the silver to cool and return to forging until the project is complete.
Polished Hammer
Check your hammer from time to time to be sure it is polished. Marks on the hammer will cause unsightly marks to be imprinted on your forged sterling silver. Stop and polish the hammer, as needed, if you develop scratches on your hammer due to use or misuse.