A soldering iron is a device for applying a point source of heat to melt solder for soldering two materials together. Soldering irons are typically electrically powered.
Small cordless soldering irons are available for fine electronics work. Some are not self-heated but are designed to be heated in a furnace with the advantage of being cordless. Soldering irons may have interchangeable tips for different types of work. Pyramid tips with a triangular flat face are useful for soldering sheet metal. Fine round tips are useful for electronics work.
Soldering irons often come with a stand to hold the hot iron. The stand may have a sponge and flux pot for cleaning the tip. Some soldering irons for professional use come as part of a soldering station, which allows the exact temperature of the tip to be adjusted, kept constant, and displayed.
A general rule is that the tip of the soldering iron be cleaned and coated with solder between sessions of use.
Soldering for plumbing typically does not use a soldering iron but a blow-torch instead.
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