Video: A look into laser cutting

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By Johnny Lu | Aug 01, 2019
Laser cutting technology at GMN

Whether it’s etching, engraving, or cutting materials, laser technology plays an integral role in the fabrication and decoration of various components. But how does laser technology exactly work? Which materials can a laser cut? What are the key advantages of utilizing lasers in the manufacturing industry? By demonstrating the working of a few laser cutters at GM Nameplate (GMN), our recent video will answer all the above questions. 

As seen in the video, a laser is mounted on an X-Y motion stage of the cutting machine. Installed perpendicular to the substrate, the laser moves across the surface to heat, melt, and vaporize the material. As opposed to a standard flashlight, the light released here is coherent, monochromatic, and directional. The core cutting characteristics, such as depth, speed, and power, are dictated by the wavelength and the frequency of the laser light.

The laser cutters at GMN can be categorized into the following three types -

  1. Fiber laser – Creating light by banks of diodes, fiber laser channels and amplifies light through a fiber optic cable. The wavelength created by a fiber laser is ideal for marking and etching intricate patterns.  
  2. CO2 laser – Utilizing CO2 as the amplifying medium, CO2 laser uses an electrical charge to excite the gas in a discharge tube to emit light. The frequency of this laser is ideal for cutting a broad range of substrates.
  3. Nitrogen laser – Similar to a CO2 laser, it uses nitrogen as the lasing medium to produce the cutting beam. At GMN, a nitrogen laser is employed for cutting aluminum and stainless steel.

To control the quality of the output, the above laser cutters can also be accompanied by an assist gas such as nitrogen or air. The assist gas curtains the laser beam to swiftly vaporize the material after cutting, ensuring smooth and unblemished edges. Nitrogen gas assist is particularly suited for projects where upholding the aesthetics of the material is critical. By creating an inert field around the laser, nitrogen gas protects the substrate from unwanted flaming or burning. For any given application, it is the interplay of several factors such as design specifications, anticipated volumes, tolerance requirements, and cost restrictions, that determines the most appropriate laser type to utilize.

With machines ranging from 30W to 400W, GMN employs low-powered fiber lasers for etching and engraving. High-powered CO2 and nitrogen lasers are typically reserved for cutting thicker materials and metals. The wide array of laser machines allows GMN to cut numerous substrates including 3000 and 5000 series aluminum, magnetic (430) and non-magnetic (304 stainless steel) alloys, Lexan, acrylic, foam, polyester, polycarbonate, and vinyl. During laser cutting, calibrating the focus point of the laser beam is extremely crucial to achieve the utmost precision. Most machines at GMN are equipped with a computerized calibration system, where a focal arm travels closer to the material, gauges its thickness, and automatically adjusts the focal length of the laser.

Versatile and easy to use, laser technology is extensively utilized at GMN for fabricating materials with extreme accuracy. When compared to other die-cutting techniques, the lead time for laser cutting is extremely short and last-minute changes to artwork can be quickly accomplished. Ideal for rapid prototyping and low-volume programs, laser technology is well suited for cutting complex shapes, creating registration holes, engraving intricate patterns, etching serial numbers, and more.

To see some of the laser cutters at GMN in action, watch our video below.