How to use a soldering iron safely

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Soldering has been around almost as long as domestic electricity as a method of securely connecting electrical components. The basic premise is to heat two metal components that are close to each other, then apply a filler compound (solder) that melts at this junction, thereby sealing the cracks and crevices with a pliable conductive metal. Learning how to solder is straightforward but remembering how to solder safely requires a bit more diligence.

Put on safety glasses. Rest the soldering iron on a secure stand in the centre of a table or work area. Avoid placing it near the corner of a desk or workbench where it could be knocked over. If using an extension cable, position it so that nobody trips over the wire and dislodges the hot iron.

Pour some water on a sponge and place it near the heating iron. After the iron has warmed up for several minutes, test to see if it is at operating temperature by touching a piece of solder to the tip of the iron. If the solder melts, the iron is ready.

Wipe the hot tip of the iron on to the damp sponge, using a sliding motion. Repeat this motion on all sides of the tip. This will clean the tip of any debris. When the tip is clean, briefly touch a piece of solder to the tip then pull it away. The new solder residue on the tip, called "tinning," helps the heat transfer from the iron to the materials being soldered.

Grasp a roll of solder compound. Unroll about 10 cm of the flexible conductive metal and place it beside the materials to be soldered. Inspect those materials briefly; this will be the last chance to make any changes before joining them as a solid connection.

Pick up the soldering iron and hold it like a pencil. Your grip should be loose, and your hand should be near the base of the tool's handle. Place the hot tip of the iron in contact with the components to be soldered. The contact must be solid, because you need good heat transfer to take place before the solder can be applied. Hold the tip in place for several seconds.

Touch the end of the solder against the materials to be joined. Slowly allow more solder to melt on to the connection. After the connection has a slight bulge, remove the iron and the solder.

Allow the soldered connection to cool for about 15 seconds, then thoroughly inspect the new joint. If you see any areas where the connection is not coated in melted solder, repeat the process. When you have soldered all the necessary connections, unplug the iron and allow all components to cool.

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