Always coat the jewelry with boric acid by dipping it in a solution of boric acid and alcohol. Then, burn off the alcohol leaving an even coating of powered boric acid over the jewelry. When heated the boric acid will turn glassy, forming a barrier from oxygen in the air, keeping the jewelry from oxidation. Boric acid also acts as a flux. Often this is all the flux you will need to solder; however, sometimes additional flux will need to be added.
If enough flux is not used the metal will oxidize, and the solder will not be able to flow properly; however, you can use too much flux. If too much flux is used the glassy coating of the flux will hold the solder away from the metal not allowing it to flow into the seam. If this is a problem, use your solder pick to scrape away excess flux. Then, continue your soldering.
For articles on Jewelry Making go to: http://GuideToJewelryMaking.com
Bench Tips and Tricks for Bench Jewelers, and Goldsmiths





