Here is an excerpt from Complete Metalsmith to whet your appetite:
Rules for Soldering:
- The pieces must be a tight fit.
- The joint and solder must be clean: no grease, pickle, buffing compound, etc.
- Use flux to protect the metal from oxidation. Each reheating usually requires refluxing.
- All the pieces being soldered should reach soldering temperature simultaneously. Heat the adjacent areas to reduce the flow of heat away from the joint. Take into account heat sinks such as binding wire, steel mesh, and locking tweezers.
- When possible, position the torch so as to draw solder through a joint. Generally, avoid directing the flame at solder.
- Use just enough solder to fill the joint.
- When soldering an enclosed area, provide an escape for the steam trapped inside. If not vented, this will expand and cause the piece to explode.
- Metal temperatures are judged by colour changes which can be seen best in a dimly lit area. Whatever your lighting. Keep it consistent.