What is brazing and how is it different from welding?
Rather than heating the tube ends up so much that they melt, which allows a weld to be created, a lower temperature is used. At around 800°, a material known as braze is introduced at the joint and this melts into the gaps between the finely mitred tubes and the lug. When it cools, the braze is what holds everything together. A version of braze known as silver solder only requires heating to about 600-650°, which means the tubes are weakened less by exposure to heat. Silver solder is almost always used for small brazed-on fittings such as bottle cage bosses, cable stops and rack mounts, and may be used throughout. Most builders use a welding torch with an oxyacetylene flame to heat the lug, tube and brazing rod, though some still use an open hearth for a less localised heat.
