To weld two pieces of copper, melt solder between the pieces of metal you wish to join. The process involves cleaning the metals, applying flux paste, hitting the metals and then melting the solder to fill the joints. You need a wire brush, flux paste, a soldering iron, a solder and the two pieces of metals to be welded. The process generally takes a few minutes, but it can take longer depending on the size of the metals.
- Clean the copper metals
Use a wire brush to clean the metals. Grease or debris should not remain on the soldering surfaces. If the surfaces are pipes, clean the interiors and exteriors thoroughly.
- Apply flux paste
Use a flux brush to apply a thin layer of flux (soldering paste) on the soldering surfaces.
- Heat the metals
Use a soldering iron to heat the larger metal of the two. Hold the flame all around the metal to ensure it heats evenly. Hold the flame in place for several seconds or until the flux paste begins to sizzle.
- Melt the solder into the joint
Hold the solder against the junction of the two metals, and melt it with a soldering iron.
- Clean the joint
Wipe away excess solder with a rag.