How It's Made: Mouth-Blown Glass

Bendheim offers authentic mouth-blown glass for architecture, art, and the home. Each two-foot-by-three-foot artisanal glass sheet is made by hand by the skilled glass masters at Glashütte Lamberts of Germany. Bendheim stocks approx. 500 colors and designs of this exclusive mouth-blown glass, offering abundant design possibilities. For more information, visit: https://www.bendheim.com

TRANSCRIPT:
Lamberts Glass is located in the small German town of Waldsassen, near the Czech border.

The factory has been producing clear window glass and colored art glass since 1906. The process of making mouth-blown sheet glass has been unchanged for centuries. Glass has three main ingredients: silica, lime, and soda. The raw materials are heated to a molten temperature of about 1500 degrees Celsius.

A gather of glass on a blowpipe starts the fabrication process. Shaping the initial gather is critical to the later step of blowing the glass into a cylinder. Sometimes another color, or multiple colors, are applied as a second step. Here pieces of white glass, called frit, are added; they will create a lovely dappled pattern on the final sheet. Additional gathers ensure that enough glass is on the blowpipe.

Craftsmen repeatedly work the hot glass into the perfect shape. The skilled Lamberts crew works together in a tightly choreographed ballet of tasks, ready for each need at precisely the right moment.

The master glassblower reheats the glass in a special furnace called a glory hole. It is soon ready for the most critical step: blowing into a cylinder. Using a special trough, and sheer talent, the master blows a large air bubble into the glass, forming an even-walled cylinder. The bottom is removed. The sides are straightened with a rod. The cylinder is transferred to a device called the pliers. The blowpipe is removed. Excess glass is trimmed off and the cylinder gets a final shaping.

A runner takes the completed cylinder to an annealing oven, which brings the glass slowly to room temperature. Each cylinder is scored length-wise and cracked open. This break allows it to be reheated and flattened. A conveyer takes the glass into a special furnace where it is flash heated and softens. A worker prods the glass into a roughly flat form, then irons it with a water-logged block of wood. All bumps are removed, leaving a perfectly flat sheet of mouth-blown glass.

A final annealer brings the glass back to room temperature. Every piece is inspected for quality. Each sheet is carefully packed in a sturdy wooden crate for delivery world-wide.