What must be done before making soldered splices?

Before making soldered splices, it is essential to ensure that the wires being joined are mechanically secured. This step is crucial because it prevents movement between the wires during the soldering process, which can lead to an unreliable connection. Securing the wires helps to maintain proper alignment and stability so that the solder joint can form effectively without any gaps or movement, leading to a stronger and more durable electrical connection.

In addition to securing the wires, other preparatory steps such as labeling, inspecting, and cleaning may also be necessary, but they do not pertain specifically to the soldering process itself. For example, cleaning is indeed important to remove any oxidation or debris that could interfere with the solder joint, but the immediate focus for soldering effectiveness is ensuring that the wires are held firmly in place.