Bottleblowing

Bottleblowing is a glassmaking technique used to shape hollow glass vessels, such as bottles, by inflating molten glass inside a blowpipe. A glassmaker gathers molten glass on the end of a hollow rod, shapes a preliminary form on a marver, and then blows air through the rod while supporting and shaping the vessel with tools to create a continuous body and a narrow neck. The lip is finished, and the bottle is either removed from the blowpipe or finished with a pontil rod. The finished piece is typically annealed in a kiln to relieve internal stresses.

Bottleblowing can be performed as free-blown work, mold-blown work, or a combination of both. Free-blown bottles offer more variation in form but require considerable skill, while molds (including mechanical molds in industrial settings) produce consistent shapes and sizes. In modern manufacturing, automated bottle production commonly uses blow-and-blow or press-and-blow techniques to produce large, standardized bottles.

Materials and finishes: the dominant material is soda-lime glass; colorants, overlays, and decorative attachments can be applied during forming or by later processes.

Applications and history: bottles have been produced by glassworkers since antiquity, with significant development in Europe during the medieval and early modern periods. Industrialization introduced high-volume, machine-made bottles, while artisanal studios continue to practice traditional bottleblowing for artistic and functional pieces.

Safety and training: working with molten glass and hot equipment requires specialized training, protective gear, and strict safety procedures, including controlled annealing and handling of hot joints.