Wednesday, October 16, 2013

Tips for Working with Gold-Filled and other filled metals


Filled metals, like gold-filled, are an inexpensive alternative to using gold in your jewelry designs. The outside layer of gold is much thicker than plating and can even survive soldering at high temperatures. But care has to be taken to avoid exposing the base metal core. These tips from my second book on soldering, Soldering Beyond the Basics, will help you successfully work with gold-filled metals. 

  • Keep filled metals protected during storage. Store wires and sheets separately in plastic bags to minimize scratches.
  • Rest it on soft leather to minimize work marks while filing, etc.
  • Joins must be aligned perfectly for soldering. There's too little gold to file or sand, by hand or with a flex shaft. Just a little filing can expose the base metal core, but you won't know until days later when it tarnishes.
  • Try to match the color of the joins by using 14k or 10k yellow gold solder. A yellow tinted sterling solder is also available, but it only comes in one temperature (medium).
  • Fill joins without overfilling. Use smaller pieces of solder to avoid big lumps.
  • Prevent firescale by using Pripp's flux.
  • Because of the bond between the two metals, the melting point is lower. Never use hard solder. Use medium, easy or extra-easy. A lower temperature flame, like butane, is less likely to burn your gold filled metal. If a small mixed gas torch is used, like a Smith Little Torch, use a medium flame and be gentle with the heat.
  • If your gold filled turns a coppery rose color after pickling, use pumice powder to gently clean the surface. Often this will return the gold color. 
  • Try to fix any scratches or problems with burnishing, which will polish without abrasion. A tumbler with mixed stainless steel shot is a safe way to polish.
  • If you still need to polish with abrasives, use the finest grits for polishing, like radials: blue 400 grit, peach 6µ and green 1µ.
Check out our workshops in fabricating with gold and sterling at SilveraJewelrySchool.com. And follow us on Facebook for more updates and tips.