The Cold Heat soldering tool is an unusual tool. It melts silver solder, which is an alloy that softens at low temperatures and hardens when it cools. Solder (pronounced "soder") can be used to connect electronic components. However, it can also be used to make jewelry or stained glass. You can repair or attach pipe lengths to each other with the right kind of solder. read on to Understanding the function of cold heat soldering iron...