Glass Work

History

Artisans have been manipulating glass for thousands of years and continue to be inspired by its unique qualities. Malleability, color receptivity, and the ability to "dance" in light are just some of the enticing characteristics of glass.

The ancient Egyptians and other Mesopotamian cultures discovered glass around 3000 BCE and used it for pottery glazes before determining the substance could also be used to craft beads and vessels. Among the many fine examples of early decorative glass are gilded and enameled glass bottles, vases, and bowls.

Glass became a prominent architectural feature during the Middle Ages as cathedrals were outfitted with large stained glass windows. Many of the early medieval stained glass windows are a combination of colored glass and paint applied onto clear glass.

In 1291, when the glass blowing industry in Venice had expanded to the point where the city was in constant danger from fires, all hot shops were relegated to the nearby island of Murano. There the industry flourished, earning Murano its title as the world capital of the glass industry. The glassmaking techniques that allowed Venetians to create millefiori designs, fine leaded crystal, and looking glasses (mirrors) were held in secret, ensuring many generations of Venetian glass artisans a lucrative living and allowing Murano to retain its title for centuries.

Most glass objects were crafted by hand until the twentieth century, when the industry mechanized. With hundreds of perfectly-formed, inexpensive glass items widely available, the art of glass blowing dwindled.

The recent glass revival can be attributed in part to Dale Chihuly, one of the world's most renowned glass artists, who built the first glass blowing hot shop in Seattle in the late 1960s and founded the Pilchuck Glass School. While Seattle developed a prominent glass blowing industry, the glass art movement swept across the country.

The current interest in flameworking (lampworking) glass beads, a technique that uses a gas torch, was also sparked by the contemporary jewelry craft movement. Flameworking can be traced to ancient Rome, but was used throughout history primarily for scientific objects.

In addition to a vibrant glass art industry, the United States also boasts some of the finest glass collections in the world, including the Corning Museum of Glass in New York and a new glass art wing at the Toledo Art Museum in Ohio.

The glass arts include a variety of cold, warm, and hot glass techniques, which can be used to fashion a multitude of decorative and functional objects.

Most techniques require the following supplies:

• Safety glasses: To be worn during warm and hot techniques as well as cold techniques involving cutting, polishing, and other potentially dangerous procedures. Hot and warm methods require didymium glasses.
• First aid kit
• Color wheel: For designing projects.
• Glass suitable for technique. Glass can be purchased in sheets, rods, scraps, frits, or in powder form, molded designs, and more.
• Grinder (or files) for smoothing edges
• Glass cleaning supplies
• Good lighting

Kiln work and flamework may require additional supplies:

• Hot gloves
• Adequate ventilation system
• Heat resistant surfaces
• Annealing kiln and related accessories for fusing, slumping, and other hot techniques
• Fiber annealing blanket (if not using a kiln)
• Gas/oxygen torch, fuel, and table clamp for flameworking
• Molds for casting, and related casting accessories

Mandrel

Paddles

Rods

• Shaping tools
• Marvering pad
• Special effects tools
• Hot glass shears and rod cutters

Pliers

• Tweezers

Other necessary supplies may include:

• Gas or propane crucible furnace or other furnace (one can also blow glass using a torch)
• Blowpipe or "punty"
• Glass blowing jacks

Supplies needed for cold glass techniques:

• Engraving: High-speed rotary tool with various extensions and safety equipment.
• Etching: Resist, sandblasting equipment, and safety equipment, or etching creams and liquids.
• Decorative glass painting: Glass paint, brushes, and outliners or leading tape.
• Decorative glass stamping: Embossing or heat gun, embossing powder (or glass paint) and rubber stamps.

Techniques

Cold glass techniques include stained glass work, cutting, engraving, etching, carving, painting, stamping, and any other embellishment that does not require the use of heat.

Etching and carving are used to permanently embed designs in glass. Surface etching "scratches" the surface, while carving goes deeper into the glass. In both cases, a resist protects the areas of the design that are not etched or carved. Traditionally, a sandblaster is used to "blast" away the glass, yielding a frosted design. Carving often involves multiple steps using a different amount of abrasion or air pressure each time to create a more varied appearance. An alternative method of etching involves using chemical etching cream and liquid in lieu of sandblasting.

Engraving requires a rotary tool to scratch or score fine lines onto the glass. A range of decorative effects are possible.

Painting on glass can be accomplished with acrylic or oil paints, but special glass paint is used more often. To achieve a design that resembles stained glass, outline the design with relief paint and when dry, fill with glass paint. Reverse painting on glass is also an option.

Warm and hot glass work require extremely high temperatures to soften the glass so that it can be shaped, fused, poured into molds, or blown. While glass blowing furnaces are usually kept at 2,000° Fahrenheit or higher, kilns are set at 1,700° or much less. Kiln work is termed "warm" glasswork because of the lower temperature required.

In a molten state, glass can be pulled like taffy, shaped like clay, or slumped into flat panels. All surfaces used to heat, shape, and blow the glass must be prepared with a coating of kiln wash to prevent sticking. To prevent breakage during the cooling process, all heated glass objects must be annealed. Annealing is the process of cooling glass slowly to ameliorate the tension created between thick and thin sections that cool at different speeds.

Glass blowing is used to form circular shapes, such as bowls and vases, and is most often performed in hot shops by a team of artisans. The central focus of the hot shop is a glass blowing furnace into which a teammate will stick a rod with a piece of molten glass, known as a "blob," attached. The blob is heated repeatedly during the shaping and blowing processes. Handles, feet, and other extraneous parts are then fused on to the object before the annealing process.

Kiln work includes fusing, the process of joining different pieces of glass together, and slumping, in which a sheet of glass is heated to the point where it "relaxes" and with the aid of gravity, is pulled down into a mold or to form another object. Kiln work is often combined with other hot and cold glass art methods.

Flameworking (lampworking) is used to make beads and other small objects. One method involves heating a rod or cane of glass in the flame of a gas torch until the glass is malleable. The hot glass is then wrapped around a hot mandrel to form the bead. Color designs are accomplished by fusing colored pieces of glass onto the surface while hot.

Trends

Glass blowing and flameworking are at the forefront of the glass art movement and attract many amateurs as well as seasoned artists. Much of the interest in flameworking is directly related to the beading and jewelry-making craze.

Etching creams, faux glass painting, and stamping on glass are among the newest cold glass techniques that offer craftspeople a means of self-expression.

While glass-blowing equipment was once impossible to transport, smaller, portable furnaces have become available, allowing artists to travel for demonstrations and instructors to give classes over a wider geographical area.

Many instructional videos on glass art techniques have been posted on YouTube by enthusiasts and the Corning Glass Museum.

Glass Art for Fun vs. Profit

One may find employment in the commercial glass industry as a glassblower, designer, or assistant. A knowledgeable artist can publish books, work in restoration for museums, or teach courses. Custom designs for commercial and personal needs, as well as one-of-a-kind pieces for the craft market, may keep a talented glass artist busy. Many artists now sell their work primarily through online stores.

Learning More

Organizations

Corning Museum of Glass <http://www.cmog.org/>

Glass Art Society < http://www.glassart.org/>

International Society of Glass Beadmakers <http://www.isgb.org/>

Books

Beveridge, Philippa, Ignasi Domenech, and Eva Pacual. "Warm Glass: A Complete Guide to Kiln-Forming Techniques: Fusing, Slumping, Casting." Asheville, NC: Lark, 2005.

Halem, Henry. "Glass Notes: A Reference for the Glass Artist." 4th ed. Kent, OH: Franklin Mills Press, 2006.

Le Van, Marthe. "Simple Glass Crafts: 36 Beautiful Projects: Painting, Etching, Stained Glass & More." Asheville, NC: Lark, 2002.

McKelvey, Jim. "Art of Fire: Beginning Glassblowing." St. Louis: Third Degree Press, 2006. (includes DVD)

Mears, Elizabeth. "Flameworking: Creating Glass Beads, Sculptures & Functional Objects." Asheville, NC: Lark, 2005.