ABS plastic (a copolymer of acrylonitrile, butadiene, and styrene) is frequently used in the manufacture of electrical connectors because of its impact strength and electrical insulation properties. When marked with CO2 lasers, ABS typically provides an engraved mark. Although no color change occurs, the engraved mark reflects lights well enough that the mark is easily readable under most lighting conditions.

To produce the high-contrast, deeply engraved mark specified by the customer, we first created a non-marking outline of the connector’s mark area using WinMark Pro’s Rectangle tool. We then added two text objects and positioned them precisely using the four-digit accuracy of WinMark’s Object Transformations dialog. The part description text object has a Text Height value of 2.54 mm (0.10”) while the date code object has a Text Height of 1.27 mm (0.05”) with 0.20 mm (0.008”) of Extra Character Spacing.

When cutting glass with a CO2 laser, the best “laser only” applications are typically thin glass substrates in the range of 30 to 600 microns (0.0012” – 0.0236”) thick. Without using specialized, and in some cases, proprietary processes or equipment, thicker types of soda-lime (float) glass are difficult to laser cut in one step.

The exceptions to this rule are the stained glass samples shown here that cut very well using a Synrad sealed-CO2 laser in a typical flatbed cutting setup. As with standard float glass, straight-line cutting of stained glass is easily done by scoring and snapping. The difficulty, as any stained glass artist will tell you, is in creating irregular shapes. Traditionally, curved shapes are made by nibbling away at the contour, by grinding on a diamond wheel, or by cutting with a diamond-blade bandsaw; however, all these options are time- and labor-intensive processes.

Our cutting setup for these opaque and translucent stained glass samples consisted of a Firestar f400 laser with beam delivery provided by an XY “flying optics” system. Beam focus was through a 63.5 mm (2.5”) positive meniscus lens that provides a 100-micron (0.004”) spot with a 1.8 mm (0.07”) depth of focus.

In addition to creating the brilliant hues and colors characteristic of stained glass, the addition of metallic oxides or metallic salts to the glass formulation appears to alter the glass structure so the laser’s intense, localized heating cuts through the stained glass without causing thermally induced micro-fracturing. Cut edges exhibit the same type of striation patterns seen in metal cutting where vaporized and molten material is blown through the cut area by high-pressure assist gas.