ART OF STAINED GLASS
Spectrum glass is universally recognized as a good "beginner glass." Done in vast batches following exacting industrial standards, sheets of Spectrum glass can be relied upon to have a smooth, easily scored surface, and follow the score line with great predictability when breaking. Many of their textured glass also cut with ease. Glass hardness (the force needed to apply to break) is average. Hardness increases with the amount of opalescence in the color mix.
Wissmach is another so-called "beginner glass" celebrated for its numerous small bubbles, a specialty. They also have a great selection of multicolored streakies and attractive iridescent surfaces. Glass hardness is soft to average.
Uroboros is a US maker of art glass that is widely known for its fabulous color and texture combinations, as well as drapery glass and ring mottles. Their pinks and purples are unequaled. They specialize in opalescent glass ressembling Tiffany's own, and it is prized by lamp makers. Glass hardness is "hard" meaning that the break requires more force than the previous manufacturers'. For this reason, the textured surfaces and orange peel underside, Uroboros is not considered a "beginner glass." Frequently, in order not to waste this precious material, one is called upon to tap the score in order to insure a reliable break. Drapery glass is best cut with a saw. Do not be intimidated by all Uroboros glass. Fancy fracture/streamer glass on a clear base is a breeze to cut.
Unlike other art glass that is sold by the square foot, Bullseye is sold by weight. It is reknowned for bold ring mottles, and peerless turquoise and turquoise blends, as well as cranberry colors. The glass is quite hard, occasionally brittle, and too often disobeys the score line and the break runs off in a different direction. As with Uroboros, tapping the score can be helpful.
This art glass stands out for its many peculiarities. First of all, its opalescence is not created with white pigments, but out of a multitude of tiny grains and irregularities within its substance. The lack of dense white pigment, and the irregularities combine to produce a very soft glass, one that requires very little force to break. The surface is very grainy as well, scores with gentle pressure, but the break often runs off the score. "Tapping" is recommended. When reflecting light, Youghiogheny glass is amongst the darkest, reflecting little. However, when transmitting light, when light traverses it when used as a window panel or a lampshade, it reveals the bright, glowing colors within. In fact, Youghiogheny glass is the brightest, and sets itself apart from the other manufacturers' product. This distinctive glass is not particularly well suited for projects where it will not transmit light to any significant extent, such as boxes, clocks, cabinet doors, etc.
Ready to grind
After your glass is cut, you are ready to grind. Simply trace the pieces on the glass. Straight lines can be abutted, but there should be enough glass eround each piece to be able to cut pieces around it, approximately 1/4" (0.5 cm).
After the glass is cut, protect your pattern with a clear transparency, and lay your pieces on it.
How To Cut Glass
page 7 (how to cut glass, by manufacturer)