Glassblowing is a centuries-old tradition with time-honored techniques that have created extraordinarily beautiful pieces for art and every-day use alike. How is glass blown today and how can glassblowers create ornate, functional glass pipes and bongs? Here’s a closer look at how glass is blown.
Glassblowing works through the concept of inflation. By introducing a small amount of air to a molten clump of glass, the glass expands and can be shaped. In the molten state, it remains viscous and can be formed into different shapes. Eventually, as the glass cools, it hardens.
There are even glass blowing competitions where artists compete and their works are voted on. One notable competition, dubbed “The Pipe Classic,” is hosted by the legendary smoke shop Bern Gallery in Burlington, Vermont, and brings people from all over to celebrate glass blowing.
Let’s look at the molecular structure of glass. While glass is a solid, its molecular structure is more akin to a liquid. Glass is known as an amorphous solid, with molecules that are more randomly positioned and weaker than in other solids. These properties are what make glass transparent.
A glassblower starts by mixing a batch of glass inside a furnace. There, a crucible is used to melt glass at temperatures of more than 2,000 degrees Fahrenheit.
The lead glassblower, called the gaffer, uses a blowpipe, usually made of iron or steel and four feet long. The blowpipe is inserted into the crucible and removes a glob of molten glass. The glassblowers roll the molten glass on a steel table called a marver to give it a cylindrical shape. The gaffer blows into the tube to create a bubble in the glass. The rolling continues, keeping the pipe and glass in constant motion. It can regularly be reheated to keep the temperature above 1000 degrees. More layers of glass can be added using a gathering iron or by dipping the glass back into the batch.
● Block, a wooden wetted shaping tool
● Jack, a bladed tool used for shaping and cutting glass
● Heat shields and paddles, for shielding the glassblowers from the heat
● Tweezers, used for grabbing and shaping hot glass
While the mouth end of the glass is being shaped, a pontil, a smaller metal rod, is attached to the base. Later, the pontil mark is ground or polished away. Blowing, turning, and heating continue, often for several rounds, until the desired shape is achieved. The piece is then transferred to a punty, which is a steel pipe heated over flames. This transfer enables the glassblower to create the opening in the glass. Following the completion of the mouth, additional heating and shaping may be required. When the piece is finished, the blower hits the punty, knocking it off the piece and into a box filled with fire blankets.
Adding Colors Colorants can be added via laminating with heat or adhesives, threads and wraps. All are used to add decorative patterns. Glass that is partially blown is called a parison. As it’s being turned, different techniques are used to add colored glass. Powders, frits (granulated pieces) and bars are all used to create designs and patterns. The glassblower rolls the heated glass over the colors, picking up pieces each time. The entire piece is heated more to melt the new additions.
In the final stages, the glassblower polishes and grinds the piece to perfection to rid it of marks and sharp edges. Often the glassblower will be using one hand to keep the glass turning while using other tools – from cherry wood blocks to stainless steel tools to wet newspaper – to form the finished piece.