Splicing small-gauge wires together is a quick and simple task with butt connectors. As the wire size increases, butt connections become less efficient and the best technique for splicing the wires together is with rosin-core solder. This is especially true when the large wires are dissimilar sizes.
Strip the ends of the two wires to be soldered together about 2 inches with the wire strippers. Twist the exposed copper wires together as tightly as possible. Get it right the first attempt because the copper gets brittle the more it is worked.
Lay the wire on a piece of scrap wood. Apply direct, high heat to the copper wires with the solder gun and feed a strand of solder into the heat. Keep the heat going and work the solder up and down the twist until the solder flows into the connection.
Allow the soldered joint to cool, however, before the repair has completely cooled, wrap electrical tape around the repair. This greatly improves adhesion.
