|Stained Glass • Fusing • Mosaics • Jewelry Supplies|
|Fusing glass in a kiln is a fascinating technique that enables artists to create unique and gorgeous projects. The following fusing rules and firing instructions should provide you with enough information to make a variety of projects, creating an appreciation for the complexities and potential of fused glass, and paving the way for more intricate designs and ideas.|
|I. Tested Compatible|
|A.||All glass has a coefficient of expansion, or COE.|
|B.||Glass manufactured specifically for fusing is often "tested compatible," or guaranteed to be a certain COE.|
|C.||The most popular fusing glasses are either 90 COE (Bullseye, Uroboros, Wasser) or 96 COE (Spectrum and Uroboros).|
|D.||Always use compatible glass, which is known to have the same COE.
|II. Slower Is Better|
|A.||You can't heat or cool glass too slowly. Going too fast can result in cracked glass or Thermal Shock (photo 1).|
|B.||A safe rate to heat is 15o per minute (900 o per hour), although stacked glass 2" in diameter and smaller can be heated at a faster rate.|
|C.||Slow-cooling of glass or "annealing" depends on the thickness of the glass. If the glass breaks because it was heated too fast; turn off the kiln, allow the glass to cool, push it back together, and try again - at a slower rate. Breaks from thermal shock usually go straight across the piece and have a little hook near the edge. They can usually be repaired by refiring.|
|III. Glass Likes To Be ¼" Thick|
|A.||When heating glass to full fuse, anything with less mass will shrink up, anything with more will spread out. This movement can be controlled somewhat by fusing slower, and not going to full fuse.|
|IV. All Kilns Are Not Alike|
|A.||There are some variances between kilns, especially mini kilns. Sometimes pyrometers are slightly off, and sometimes current loads vary.|
|B.||Use firing schedules as a guide, but remember to check your piece frequently during fusing, and record changes in schedules as needed.|
|C.||Prepare your kiln by applying kiln wash with a kiln brush. Apply one thin coat in each direction. Don't forget to apply kiln wash to molds, too.|
|V. Take Good Notes|
|A.||Use a project log to keep important information about your projects.|
|B.||Keep track of what glass was used, how thick the glass was, the firing schedule and the results.|
|C.||This helps repeat good performances and prevent bad ones.|
|VI. Fusing Glass|
|A.||Glass Fusing Stages For Mini Kilns
Use for table top kilns, pieces ¼" thick, and 3" - 6" in diameter (larger pieces should be heated and cooled slower to prevent thermal shock.
|C.||Once the desired look has been achieved, turn off the kiln.
|D.||If more melting is desired, turn dial to 5, but do not leave kiln.
|VII. Basic Supplies
Listed with Delphi item numbers for quick reference
|1.||#HB120||Table Top Kiln|
|2.||#7441||Ceramic Kiln Shelf - 6"|
|5.||#FIREUPS||Tested compatible glass - Uroboros Glass Pack, 90 COE|
|6.||Glass Cutting Supplies
|7.||Variety of Bending Molds
|VIII. Kiln Parts|
|All glass fusing kilns have basically the same parts:|
|A.||Elements (high temperature coiled wire)|
|C.||Stainless steel cover|
|D.||Thermocouple (high temperature wires covered by ceramic rings)|
|E.||Pyrometer (temperature read out dial)|
|F.||Infinite Dial - some kilns simply have an on/off switch; the Hot Box pictured has the Infinite Dial|
|Photography and instructions from Glass Fusing Made Easy book #5981. For more information and project ideas refer to this book and Delphi's fusing favorites:|
|Fused Glass Handbook #6430
Fusing guru Gil Reynolds presents 25 projects with easy to follow instruction for mold-making, creating pattern bars and many other hot glass techniques.
|Kiln Crafted Video #4990D
Discover how glass shaping techniques developed thousands of years ago have been put to use by contemporary artists. Observe different stages of the glass melting process. Learn how to turn ordinary glass into beautiful sculpture as well as forming, mold materials, preparation, heating and cooling cycles, and more. Includes example projects ranging from beginner levels to advanced.