A Warm Winter Hobby

 Impact of temperature on glass blowing

Glass blowing is a technique that involves inflating molten glass into a shape, with the aid of a blowpipe, much like blowing soap bubbles from a wand. Molding red-hot molten glass to create an artifact requires a creative mind, dexterous hand work, and stamina.

Although the modern art of glass blowing uses more modern equipment, the essence of working with glass remains an ancient art, dating back to 500 B.C. at the start of the Roman Republic. Throughout history, glass blowers were literally held hostage for fear of their knowledge being leaked. At one stage, for Venetian glassblowers, leaving the island of Murano was a crime punishable by death!

The art of glass blowing relies on not only a steady hand but also understanding the impact of temperature on glass. During glassblowing, the viscosity of glass changes gradually over the range of temperature required to shape the artifact. To complicate things, the temperature of the piece being fabricated is typically cooler on the surface than it is in the interior. Because glass expands as it is heated and contracts as it cools, the temperature difference introduces stress. In molten glass, this stress is easily and quickly relieved because the glass is free to move. As the temperature drops and the glass solidifies, the glass-maker must anneal the glass to ensure that the stresses have been relieved before the cooling glass reaches its strain point and risks shattering!                         

Despite all this precision work, as a hobbyist, it is possible to enjoy making beads, bowls and other pieces of artwork without being too concerned about having highly developed glass blowing skills. Read about the different kinds of glass blowing here… maybe this will be your new hobby this winter!