If you have never been to a glass studio to watch glassblowing first hand I highly recommend it.  It is truly a fascinating process to see in person.  It is amazing to see how fast the artists work and feel the intensity of the heat radiating from the furnaces.  

On a cool fall day we met with the studio team of McDurmott Glass Studio in Sandwich, MA, to learn about the amazing process of glassblowing.  The studio, founded in 2002, is a metal shed structure behind the house ofhusband and wife team David McDurmott and Yukimi Matsumoto.  

For our visit they made the same wine goblets featured in the photo shoot for the American Made Dinner Table.

The studio has two furnaces heated to a sweltering 2500 degrees Fahrenheit that holds the molten glass used to make their wonderful pieces.

The process begins with the heating of the blowing iron, which is a long metal pipe, used to gather the molten glass from the furnace.  Blowing irons need to be heated because molten glass won’t stick to metal unless it’s hot.

Throughout the process, the piece is re-heated in the furnaces called the glory hold in order to keep the piece pliable.They blow the glass out by forcing air into the tube. The air has no place to go but out through the soft glass which makes a bubble. Then David explains it’s a matter of using gravity, centrifugal force, the speed at which you turn it, how hot it is, and what angle you hold it. That determines what shape you make.

They use special tools they call “blocks” that are fruitwood, cherry, apple or pear and are used to shape the glass,  round it up and make it symmetrical.

To make color, they use specialized chips of glass called frit.  Different metal oxides make different colors.  For example, cobalt oxide makes cobalt blue, potassium bi-chromate makes green, copper carbonate makes a light sky blue, manganese makes purple.   

The molten glass is dipped into the frit and then heated in the glory hold to melt the chips of glass.  Then it’s a matter of blocking it and starting the process of blowing and shaping.

In a wine goblet there are thick and thin parts to the piece.  The thick parts hold the heat and the thin parts dissipate the heat so there is a lot of internal stress between the two as they are cooling down at different rates.  In order to avoid cracking the glass is placed into what is called an annealing oven.  The annealing oven is set at 910 degrees, the temperature that prevents the glass from moveing,  and cracking.  There it sits overnight on a program where it gradually cools down. 

Watching the team, they make it look so simple, but the rule is that it takes someone about seven years of training as an apprentice to become a good glass blower.  ∂


the team outside the studio

Peter Waechter, Yukimi Matsumoto, David McDermott and Isabel Green