You’ve probably heard references to soldering (especially if you read my blog often), but do you know exactly what it is, and how it is done?
Soldering is used to join two pieces of metal together, without damaging or melting either one. This is especially useful for attaching wire together to make an electrical connection, as it will not disturb the electrical current, or for fabricating jewelry, because utmost precision is very important. For large-scale steel projects though, soldering is not strong enough, and welding is the preferred option.
The solder itself is always a metal alloy that will melt at a lower temperature than the metals being soldered.
The basic principle for most forms of soldering is a little snippet or short section of solder wire is placed on the joint, and heated. Once the solder reaches its melting temperature, it melts and forms into a little droplet. Once heated slightly past this point, the solder reaches its flow temperature, where it is so hot that it flows out at makes a shallow alloy with all the immediate metal surfaces. Thus, the two metals are joined yet without being melted or damaged. Later, the solder can be removed by heating to liquid temperature, then being sucked out with a “solder sucker” if need be.