How is a bead made? A narrow rod of glass is melted in the flame of a torch. The molten glass is wound around a steel mandrel (a think rod of steel that is coated with bead release). The mandrel actually makes the hole in the bead. Several wraps are made, and then the bead is heated up and centered. This process is repeated until you reach the desired size. On its own, molten glass will always try and maintain a round shape. Glass will flow to the heat, so the torch is used to control the direction of the flow thereby controlling the shape of the bead. Depending upon the shape desired, the bead is shaped by gravity and by tools.
Glass is added in layers, with very thin rods of glass (called stringers) being used for bead decoration. All decoration is done after the bead is obtained the desired shape.
After the bead is completed, it is placed in a kiln which has been pre-heated to annealing temperature (for soda-lime glass that temp is about 970 degrees F).The annealing process helps to strengthen the bead and prevent cracking.The kiln is gradually cooled down to room temperature, guided by an annealing schedule. While this cooling can be done by hand, most lampwork artists use a programmable digital kiln.
