When cutting glass with a CO2 laser, the optimal thickness of the glass substrate is 0.0012-0.0236 inches. Without special methods, or in some cases, unique methods, it is difficult to cut thicker soda lime (float) glass in one go with a laser.
In addition to regular glass, the colored glass samples shown in the photos were all cut with a sealed CO2 laser. As with standard float glass, colored glass is easy to cut in straight lines, which can be achieved by scoring and breaking. The difficulty is cutting irregular shapes. The traditional method is to drill holes little by little along the edges of the irregular shape to form a curved shape, and then grind it with a diamond wheel or saw it with a diamond blade, but these methods are time-consuming and labor-intensive.
The device used to cut these opaque and translucent colored glasses includes a laser with a beam focused through an XY optical system through a 2.5-inch positive meniscus lens to a spot size of 0.004 inches and a focal depth of 0.07 inches.
Adding metal oxides or metal salts to colored glass not only produces brilliant colors in the colored glass, but also changes the glass structure so that the laser energy and the localized heat it generates will not cause the glass substrate to inadvertently break. The pattern of the cut edge is said to be similar to that of metal cut edges. When laser cutting metal, high-pressure auxiliary gas is often used to blow evaporated and melted material away from the cutting area.
The jigsaw puzzle was cut with a material width of 2.25 inches and a height of 2.06 inches. The cutting power was 400 watts and the cutting speed was 50 inches per minute (IPM). At a cutting speed of 50 IPM, it took 7.5 seconds to cut the jigsaw puzzle. During cutting, 60 PSI of air was used as the auxiliary gas. Contamination scum beneath all cut surfaces is friable and easily leaves a clean laser cut edge.