What should you use to clean terminals before soldering?

Using a pencil-style typewriter eraser to clean terminals before soldering is ideal because it is effective at removing oxidation and surface contaminants without damaging the metal. The soft material of the eraser can gently scrub the terminal surfaces, ensuring that they are clean and ready for a proper solder joint. This is crucial because a clean surface promotes better electrical conductivity and adhesion of the solder, which directly affects the quality and reliability of the connection being made.

While there are various cleaning methods available, this choice minimizes the risk of scratching or otherwise damaging the terminal, which can happen with more abrasive materials like steel wool or sandpaper. Additionally, some solvents can leave residues or may not be suitable for all materials, potentially affecting the soldering process. Therefore, the use of a pencil-style typewriter eraser balances effectiveness with safety for preparing terminals for soldering.