There are several ways to etch glass. The highest-quality, most artistic method is done through sandblasting--sometimes referred to as glass carving--as it creates an elegant, 3-D effect. This method requires some rather expensive equipment, but there are other methods that are easier and more economical.
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A siphon sandblaster has a hopper that holds the silica/sand and a hand-held gun that is attached to the hopper with a tube. As compressed air is released through the nozzle of the gun, a vacuum is created, drawing the sand into the air stream. This type of sandblaster has an on/off button that immediately stops and starts the flow of sand, offering a high degree of control, and the system is easy to maintain. However, the system is not powerful enough to do any deep carving into the glass, according to the Sundance Art Glass website.
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A pressure blaster holds the sand in a pressurised container where air and sand are mixed. The air/sand mixture then travels through a tube to the nozzle. This system is more powerful than the siphon type so it is good for deep etching, but is also more expensive than the siphon-type sandblaster. Also, there is no simple on/off switch, so it is trickier to operate and is more difficult to maintain, states the Sundance Art Glass website.
Many types of abrasives are available, from silica to silicone carbide. Choices of sand include brown, white, crystal and silica. All have a medium to slow etching speed and are inexpensive. Garnet has a slightly higher etching speed and is only moderately more expensive. Aluminum oxide cuts glass more quickly than any of the sand products, but is about four times as expensive. It comes in brown, white and pink. Silicone carbide is the fastest abrasive, but is the most expensive, according to the Glastar website.
As an alternative to sandblasting, etching cream (a hydrofluoric acid-based cream) can be applied with a brush on glass over a stencil. Although etching cream is a diluted form of hydrofluoric acid, it is still very caustic so protective equipment must be worn at all times. This method is usually used by hobbyists, as it is much less expensive.
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Another option for etching glass is an electric glass engraver. It provides a different result than other methods, resembling a sketch-type image. The pattern or image to be etched into the glass is placed under or behind the glass and the narrow, vibrating tip that is held to the surface of the glass, tracing over the image.
Resist paper is a vinyl sheet that comes with an adhesive backing and is generally sold by the linear foot. It is often used to make stencils, as the etching medium will not penetrate the areas of glass covered by resist paper.
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A set of precision utility knives are required to carve stencil designs in the resist paper. Sets usually come with an assortment of interchangeable razor-sharp blades and a 3- to 4-inch handle in a convenient wooden box.