Author: Alex Davis

Basic Principles A glass cutter does not saw glass. Rather, its cutting wheel “scores” the glass—creating a shallow fissure as it rolls across the surface. This fissure, or “scoreline,” breaks the surface tension of the glass and allows it to snap when pressure is applied downwards on either side of the fissure. The cleanness of…

Plates and platters are popular projects for both advanced and beginning kilnworkers, and platemaking is a perfect way to learn kilnforming’s two most frequently used methods: fusing and slumping. The tips shown here are the basic building blocks for more advanced kilnforming methods. Because the object is to make functional plates with smooth surfaces, these…

One Final Preparation Step Before using a new kiln for glass projects, you will need to pre-fire it. This burns out binders, moisture, and other residue left over from the manufacturing process. New shelves can be slow to take on primer, so we recommend pre-firing them, too. To do this, coat your new kiln shelf…

Unleash Your Unlimited Forms Lost wax kilncasting is a versatile method for making glass pieces in almost any form imaginable. The process involves creating a refractory mold around a wax model. The wax is then removed—or “lost”—creating a cavity. Glass is cast into the cavity, resulting in a fully sculptural finished piece. This TipSheet covers…

Improve Kilnforming Results To achieve control in firing glass, it is necessary to understand how heat is distributed within the kiln you are using. Kiln heat is rarely even. Top-fired kilns tend to be hotter in the center. Side-fired kilns are frequently hotter around the perimeter. The pyrometer reads only one point within the kiln chamber…

Basic Principles BUY THE BEST CUTTER YOU CAN AFFORD. If it helps you to cut accurately and comfortably, it will save you money in the long run. Look for a cutter with a comfortable handle and a high-quality, long-lasting wheel made of carbide steel. Inexpensive cutters designed for scoring float glass have neither of these…

Simple & Essential Cleaning glass before firing it removes problem causing contaminants like glass-cutting fluid, oils, minerals, salts, dusts, fibers, sticker residues, fingerprints, and pen marks. If these substances are not washed from glass before it is fired, they may be visible in the finished glass or may cause devitrification—the growth of crystalline structures on…

General Considerations Good housekeeping and common sense go a long way toward ensuring safety in the kilnforming studio. Ventilate your studio well, keep dust to a minimum, and confine hazardous materials to a limited area. Avoid eating and drinking in the studio. Toxins and dusts are easily ingested when you handle food and kilnworking materials…

A Brief History of the Roll-Up In 1993, Klaus Moje and Dante Marioni took part in the Connections project at the Bullseye factory in Portland. Together they explored the idea of blowing fused pieces. Moje would make tiles in the kilnforming studio, and Marioni would then pick them up on a bubble of furnace glass…

Reverse-Relief Kilncasting in an Assembled Mold This TipSheet describes how to create a reverse-relief cast glass object with the optical clarity of a furnace casting, using plaster/silica design elements in an open-faced mold assembled from vermiculite board and other refractory materials. There are several advantages to this process: • Less waste than traditional kilncasting processes…

Discover One of the Most Empowering Potentials of Glass Fusing Working with a palette of glass frit, powder, and stringers, you can create unique sheets of art glass to use in stained glass or fusing projects. Using the materials and techniques described in this TipSheet, you will no longer be dependent on the selection of…

Stack Firing for Embedded Imagery This TipSheet will introduce you to ways to float imagery and color within thick blocks of clear glass. Historically, thick glass castings have resulted from pours of furnace glass or by kiln-casting glass chunks or frit. The method we call “stack firing” results, instead, from the fusing of multiple layers…

A Simple Kilnforming Technique Developed by Rudi Gritsch “Kilncarving” is a term coined at Bullseye to describe a simple kilnforming process that achieves a bas relief, textured, or sculpted look in glass. The process involves cutting a pattern or design in ceramic fiber paper, then stacking glass on top of the pattern and firing the…

The Importance of Achieving Uniform Cooling When kilnforming glass, especially largescale work, it is important to cool the glass uniformly throughout the annealing range. The temperature difference within the glass—from top to bottom, side to side, or end to end—should be no greater than 10ºF (5ºC). Such uniformity prevents a number of problems, including the…

Creating a Reliable Shelf System Creating large, finished glasswork that is flat, uniform, and well annealed is highly dependent upon having a reliable shelf system. An ideal shelf system for a large kiln must have a continuous, seamless surface and be level, stable, smooth, durable, flat and able to transfer heat uniformly. With this TechNote,…

Understanding Distortion & Trapped Air When Firing Bullseye Glass Two common problems encountered when fusing glass are distortions of shape and unanticipated bubbles. To avoid these effects—or to engineer them into your work—you need to learn how to control volume and trapped air during firing. Understanding Volume When held at its full fusing temperature for…

The Unique Nature of Glass—the Supercooled Liquid Glass is an amorphous material. Its molecules are not arranged in a regular, specific pattern, like those of a crystalline material (such as metal), but are random in their configuration. Because of its amorphous molecular configuration, glass reacts to heat differently than do other materials. Metals, for example,…

Why COE Isn’t the Whole Story A misunderstanding that the compatibility or “fit” of two glasses is solely a function of their expansion properties has led to an overemphasis on “expansion” and the numerical value of the coefficient of expansion (COE) of glass. Studio artists continually ask us for the COE of a glass, hoping…

A Key Tool for Painting with Light Fused glass is frequently characterized by a cut-and-fit approach to design. Various shapes of colored glass are cut and fired to a base blank, often a tile or plate. While this is a valid method of working the material, it comes more from a collage or mosaic than…