Putting the Frosting On The Cake.

There are two methods of etching glass: sandblasting and acid. Each has its own set of strengths and weaknesses. Sandblasting allows the artist to remove a large amount of glass from the surface creating insets. It can also be used to create gradients across a surface. By passing the nozzle across a masked area unevenly, certain parts will be sandblasted more than others. Unfortunately, fine details are difficult to achieve using a sandblaster. On the other hand, acid etching allows an artist to create intricate patterns and apply them directly to the surface of a glass piece. The only drawback to acid etching is that gradients can not be achieved like sandblasting.

Sandblasting uses pressurized air to propel sand between 60-80psi. This process physically removes microscopic particles of glass from the surface leaving behind a "brushed nickel" effect. By setting the nozzle to different pressures or moving unevenly, a variety of effects can be acheived on the surface of the glass. Resists can also be used to provide an extra level of control. A resist is anything that can "resist" the sandblasting. Generally, this is a thick tape or specialty wrap bought from a glass specialty store. The resist is applied to the surface of the glass and then cut away where sand blasting is needed.

Acid etching starts off with the creation of a stencil. A generic resist can be used like sandblasting, or -- on the cutting edge of glass etching -- a light-sensitive acid etching film can be used. When exposed to light and developed, this film yields a stencil that can be used over and over again. It consists of a microscopic mesh holding together a layer of synthetic resist. Small pores in the mesh allow the acid to soak through and make contact with the glass. The acid leaves its mark by actually creating microscopic imperfections in the surface of the glass. These imperfections scatter the light as it hits the glass and gives it the "frosted" look.