Laser Cutting Machine Fundamentals

To reach an understanding of laser cutting machine fundamentals one must understand that there are 3 different types of laser cutting machine: Flying Optics, Moving Material and Hybrid machines. These are determined by the way in which the laser is moved over the construction material. The axes of motion are named the X axis and Y axis. If the cutting head may be lowered or raised, it is typically named as the Z-axis.

The main characteristic of flying-optic laser cutting devices is the fixed work surface on which materials are placed. The laser is able to move over the work piece in both directions. This allows flying-optic cutters to keep the piece in one position during cutting, and usually do not require the material to be down. The moving mass is constant, so cutting is not affected by the changing size and thickness of the material, as would be the case with a moving material laser. These machines are the quicker of the 3 types and have faster acceleration and peak velocities than other systems.

Moving material lasers use a movable table beneath a fixed laser for moving the material below it. This type of machine ensures that the material is kept at a constant distance from the laser and gives a central point from which cutting slag or ejecta can be removed. The advantage is that it requires fewer optics. The only problem is that the weight of the material being cut is fixed by the what the table can handle. Because of the machine having to be continually reloaded and because of their weight limitations types of machine are often the least efficient.

Hybrid laser cutting machines are a combination of flying head and stationary head laser cutting machines. The table moves on one axis and the cutting head moves along another. The advantage of hybrid laser cutters over flying optics laser cutters is a more sustained beam delivery path and a simpler beam delivery system. This also makes hybrid machines more energy efficient than flying optics lasers.

Pulsed lasers are great for piercing jobs and for cutting holes. They also offer benefits when it comes to working with lightweight materials because they do not provide a steady beam which may heat and ultimately melt the work piece. Most industrial laser cutter offer the ability to both pulse or cut using a continuous wave - usually referred to as CW cutting.

For increased quality when cutting a hole, double pulse lasers can be used. These are generally employed to improve the material removal rate. This strategy is very simple; the first pulse removes material from the surface of the work piece and the other prevents the ejecta or "slag" from adhering to the area around the hole. Yet again, the benefit is a cleaner cut.

The outstanding quality of materials cut by laser greatly exceed those that have been cut by conventional means. This is because the beam leaves a clean cut surface. Using any type of laser cutter will result in more accurate pieces within a shorter amount of time than with typical cutting methods.

About the Author:
Marc Anderes is the Vice President of Operations of Maloya Laser which specializes in Metal Manufacturing and Laser Cutting with advanced laser technologies,  servicing aerospace, scientific, transportation, medical and machinery needs.