the Coombs method of glasspainting

Stained glass shifts from brilliant to sombre in a single day, and changes colour with the seasons. Transparent windows plant images into the real world. They sparkle as the viewer moves and shifts focus, creating a web of connection between Nature, human imagination, and the experience of seeing. It’s magical. For me, transparency reigns supreme.

I have developed a glasspainting recipe and application methods that allow me to maintain the sparkle of transparency, even while shading, and to paint glass easily with fluency and expression.

trace, texture & transparency

I paint glass in three stages. Each serves a specific purposes and plays a different role in the creation of a stained glass window.

  • Tracing, where lines are ‘traced’ onto the glass from an image laid underneath, is essential. Tracing creates solid graphic elements that that merge imagery with heavy soldered seams and won’t bleach out in bright sunlight. Tracing is common to most historic and contemporary styles of glasspainting. Tracing forms the foundation of painted stained glass, and requires specific design skills which can be learned.

  • Texture is the stage where I add detail and pattern, combining graphic elements with transparency and the natural brilliance of unpainted glass. Painting texture over fired tracelines is a joyful and creative activity, a time for individual expression and pleasure.

  • Transparency is where I add shadows and half-tones; adjust opacity; render form; and create depth of field in a stained glass picture. I focus on transparency, work wet, and rarely cover the entire piece of glass with paint. In traditional glasspainting a smooth ‘badgered matte’ is laid down and stippled away when dry. In place of this I leave areas of glass untouched when laying grounds or matte, and I rarely work dry, because dust fogs transparency.

a fluid story

The first time I painted glass was at Edinburgh College of Art in 1978. I was a student of Sax Shaw in the stained glass department. We were using water and gum Arabic and I found the mixture clumsy and difficult to work with. Fresh brushstrokes clumped up against those applied just moments ago (or so it seemed) and often ‘fried’ in the kiln to form bubbly lumps.

It was pre-Internet, so I asked around for advice, dug out some old books from the college library and discovered ancient recipes for mixing glasspaints with wine, vinegar, pee, fat turpentine, and various gums and oils. Eventually I settled for grinding my paint laboriously in a pestle and mortar to get a finer texture and adding drops of lavender or clove oil to stop it drying out quite so quickly. And I tried to paint faster, before the paint dried on me.

This technique carried me through fairly well for the first 15 years of my work in stained glass with one notable exception; the Crafts Council of Great Britain, rejecting my application to become a member noted that my “glasspainting was unnecessarily crude in the sample provided.” Oh dear! I just kept on painting glass anyway, and that particular panel, a self-portrait called Mask, has been on permanent exhibition at the Stained Glass Museum at Ely Cathedral in Cambridgeshire since around 1995.

The seed of an idea for mixing glasspaints with propylene glycol came from a stained glass painting workshop on the west coast of the United States in the summer of 1994. Still living in England, I was excited to have been awarded a Teaching Assistant position to Albinus Elskus at the Pilchuck Glass School near Seattle, Washington. A few months later I received the upsetting news that Albinus had suffered a stroke. Seattle glasspainters Dick Weiss and Walter Lieberman bravely stepped up to co-teach the workshop, substituting for Albinus as best they could, and keeping me as their Teaching Assistant.

Both Dick and Walt painted with enamels, and Walt especially knew a lot about different application techniques. He showed us how to make glasspaint pastels for drawing onto a sandblasted surface, talked about pine oil and explained how ‘fat turpentine’ was perfect for screen-printing. When Walt saw me endlessly grinding my paint with lavender oil in a pestle and mortar to create the smooth flow I wanted he suggested I try antifreeze. It might work better, he said. It did.

Antifreeze gave me precisely the viscosity, fluidity and long working time that I had always wanted. It flows beautifully from a pen nib; allows ample time to apply a perfect matte; fires to a gorgeous gloss; does not “fry” in the kiln; and washes off with water. The perfect medium. There was just one drawback: it’s poisonous. Antifreeze contains neurotoxins that are absorbed through skin contact.

For someone who paints with her hands (watch this 2 minute video for a zippy demo) that was quite a problem. I had discovered the Holy Grail of glasspainting with hazardous side effects. It was like taking medicine; weighing benefits against risks. I decided to go ahead.

From 1994 onwards I painted exclusively with antifreeze, including twenty stained glass windows for St Mary’s Cathedral in Portland, Oregon, where I developed a pantheon of new textural effects and application techniques. At the same time, I stopped teaching glasspainting. Antifreeze is a neurotoxin. It would have been unethical.

10 years passed before I began teaching glasspainting again, and the people who made this happen were master glasspainter Richard (Dick) Millard and chemist Warren Porter.

Dick was a wonderful friend and huge supporter from the moment we arrived in America. He had seen my stained glass during a tour of the UK in 1993, lived nearby in Antrim NH, and championed my work from the very beginning. He introduced me to the extended ‘family’ of American stained glass people. Many of whom have now become friends. Dick taught me many things, and advised me on how to survive in the New World. He also assisted me directly on the cartooning for St Mary’s Cathedral. I owe some of my most significant commissions, including 2 windows for Marble Collegiate Church in Manhattan, to Dick Millard, and he, indirectly, got me back into teaching.

It was at Dick Millard’s during the summer of 2005 that I met Warren Porter, a stained glass enthusiast and biochemist from Montgomery Village, Maryland who recommended that I switch from antifreeze to propylene glycol. It would, Warren explained, give me exactly the same results without potentially ruining my nervous system.

The rest, as they say, is history. I threw out the antifreeze and started teaching again. In 2009 the State of New York’s health and safety officials gave permission for first-grade schoolchildren (6 and 7 year olds) to paint stained glass with me provided they did not handle the materials as a dust. Excellent!

As I watch my glasspainting recipe and techniques being used by artists and stained glass painters around the world I feel a huge rush of warmth and gratitude to Warren Porter, Walt Lieberman, and to dear Dick Millard for the crucial parts they played in this.

I continue to be passionate about glasspainting and have also quietly fallen in love with the buzz I get from teaching. It is extremely rewarding watching students learn to paint so beautifully in such a short period of time.

My techniques enable even first-time glasspainters to easily transfer their drawing skills to stained glass. This page shows work of some past students, including self-portraits painted by elementary school children. You can also watch this lovely short video by Jack Criddle, and more videos of me glasspainting here Visit this page for hundreds of photos of stained glass painting and commissioned work in progress. This has been my life’s work.

addendum: from Warren Porter

I was at one of Dick Millard’s classes when you came to visit. One of our discussions was your use of “auto antifreeze” as a material for preparing paints for application. You also said that because of its toxicity that you would not allow any use except by you. The toxicity issue brought forth why you would not provide painting classes.

Having loved chemistry through high school and the studying it in college, led me to a career as a chemist for a government agency. I had a lot of experience working with a variety of toxic and non-toxic chemicals. There we analyzed many commercial products containing a variety of chemicals. These chemicals included ethylene glycol (anti freeze) and propylene glycol. Thus when you were discussing the problems of ethylene glycol, I suggested use of non toxic propylene glycol.

Thanks again Warren!

below, stained glass painted by chemist Warren Porter during a 2007 workshop in Vermont

Please email me to learn more about attending a glasspainting workshop. Fee free to send your mobile number to schedule a phone call.