Soldering any type of wire creates a bond that lasts a long time. Soldering coated galvanised wire--which is typically used for fencing, guy wires or holding a support post in a permanent position--requires that the two ends of the bare wires are clean and free of all debris so the solder can adhere to them properly The coating prevents corrosion of the wire, which is generally used outdoors and is exposed to the elements.
Clean the two ends of wire with a wire brush. This removes any large debris from the wire surface. Rub the individual wires with 60-grit sandpaper to remove the galvanised coating. The overall goal is to make the wire's surface as shiny as possible.
Lay the two ends of the wires over each other, so 6 inches of the two pieces of wire overlap each other. Twist one end of the wire over the other in alternating circular winds. Use wire pliers to aid in making the physical connection. The galvanised wires must have secure contact before they're soldered.
Elevate the wire connections so they're not laying on the ground or any solid surface.
Ignite the propane torch. Move the flame over the galvanised wire connection to heat the surface of the wire evenly. Keep the blue part of the propane flame approximately 1 inch from the wire's surface.
Extend the 1/8-inch thick solder with flux core to a length of 6 to 8 inches from the coil. Keep heating the wire with the torch.
Touch the end of the solder to the heated areas of the wire. The solder begins to melt into the twisted galvanised wire. Keep adding solder to the wire connection until it begins to drip. Withdraw the solder and the propane torch.
Allow the wires to fully cool. Paint the soldered connection with galvanised spray paint to protect the surface from corrosion.
Perform all soldering functions in a well-ventilated area, preferably outdoors. Fumes from soldering can irritate the lungs.