A soldering gun is in affect a transformer. The secondary winding has very few turns of heavy copper wire or bar, and generates a high current at a very low voltage. The bit is made of thinner copper wire, and so has a relatively high resistance. This causes the bit to heat up. one of the advantages of soldering gins is that they only takea few seconds to heat up, and also cool down rapidly afet being switched off. they are also powerful, making them ideal for tasks suc as soldering together small metal sheets and tubes, they typically produce from 50-200 watts of heat. One disadvantage is the heat regulation is not very good, also the larg bit is rather clumsy making it unsuitable for detailed work i.e. electronic circuits.

Solder A solder is a fusible metal alloy (often of tin and lead, although lead-based solders were outlawed in many parts of the world in the 1980s), with a melting point or melting range below 450°C (840°F) and is melted to join metallic surfaces, especially in the...