Prairie Isle Glassworks
DAVE JORDAN & DEL O'BRIEN
Fusing is the process of joining two or more pieces of glass through melting. "Full fusing" typically occurs at 1500°F and the glass generally melts completely. "Tack fusing" (texture fusing) is carried out at a lower temperature, around 1400°F, and the glass is partially fused i.e. the pieces don't fully melt together and, consequently, retain their texture. "Slumping" is the technique of imparting three-dimensional shape to the glass using a mold, generally at 1300°F. "Coldworking" involves grinding, shaping and polishing the glass to create particular effects or finishes.
The art glass we use is created at Bullseye Glass in Portland Oregon, using proprietary chemical formulas to impart the various colours, and hand-rolled into large sheets. This hand-made aspect of the manufacturing process can result in the formation of small bubbles in the final sheets. Fusing two or more pieces of art glass together can also result in the inclusion of small bubbles, which is part of the charm, uniqueness and distinctive qualities of a hand-made piece of glass art.
The creation of a piece of fused art glass requires sheets of glass first be cut into the desired shape(s). The pieces are then assembled and placed in a kiln. The kiln heats at a controlled rate until the required result (smooth or textured) is achieved. This is followed by a rapid cooling to 960°F where the glass is annealed for at least 45 minutes; this step is necessary to remove stress from the glass. The kiln is then cooled at a slow rate to room temperature. At this point the glass can be removed from the kiln. Depending on the artist's intent for the piece, additional fusing cycles may be required.