Shaping Hot Glass

Catherine Ayers talks about making glass sculptures

March / April 2020

Scholastic Art: What is your job?

Catherine Ayers: I am a gaffer, which is also known as a glassblower. I work for the Corning Museum of Glass, in Corning, New York. At the museum, I demonstrate the process of glassblowing to museum visitors.

SA: What kinds of objects do you make?

CA: Typically, for a glassblowing demonstration, I make a vessel. That’s an object—like a bowl, pitcher, or vase—that is used to hold something. I usually add a whimsical element to my vessels, such as sculpting the handles of a glass-blown pitcher to look like elephant trunks.

SA: What is your working process?

CA: I start by heating up the tip of the pipe—which is like a long, metal straw—in the furnace. Melted glass will only stick to hot metal. When the tip of the pipe is cherry red, I know it’s hot enough. I then dip the hot tip into the melted glass and keep spinning it to gather some glass. I can’t gather too much at one time or it will drip off. After gathering a bit of glass, I remove the tip of the pipe from the furnace and blow into the other end to create a starter bubble in the glass. I have to let the glass cool for a few seconds, and then I gather more glass and blow again to make the bubble bigger. I do that a few times until I have the amount of glass I need. Then I shape the glass into the object I’m making.

Mickey Dann, courtesy of the Corning Museum of Glass.

She rolls the hot glass in frit to add color.

SA: How do you add color to the glass?

CA: Color comes in two forms—frit and solid bars. Frit is like sprinkles of color. You roll the glass in frit that is the color you want. As you continue to work with the glass, the frit melts into a mottled effect. That’s how I added color to the elephant trunks on my pitcher. When using a solid bar, you either put it on the tip of the pipe before gathering the glass, or you put it on the glass after gathering it. Then it melts into the glass as you spin it and heat it, coloring all of the glass. That’s how I added color to the vessel part of my elephant pitcher.

SA: How often do you heat the glass when working with it?

CA: About every 30 seconds! So I never go far from the furnace. The furnace is set to about 1,100 to 1,200 degrees Fahrenheit. Room temperature can cool glass quickly, which will cause it to crack. So I have to keep the glass hot while working with it. When I’m finally done with the piece, I put it in an annealing oven. That’s an oven that slowly cools the glass to room temperature.

SA: How do you stay safe when working with such high temperatures?

CA: I wear safety glasses, cotton clothing, and closed-toe shoes. Sometimes I’ll wear a Kevlar sleeve to protect my forearm. But I don’t wear gloves. I have to keep spinning the pipe, otherwise the glass can become lopsided. And spinning the pipe while wearing gloves would be like trying to play the piano while wearing gloves.

Mickey Dann, courtesy of the Corning Museum of Glass