Since the sixties, laser cutting is a popular option due to it efficiency and quality in material processing. Laser cutting has the ability to heat, melt, and even vaporize the materials. Here we are going to share with you the process of acrylic laser cutting.
Laser cutting is a thermal process where the laser beam used to melt the focused area. Co-axial gas jet is used in laser cutting to eject the molten material to form clean edge. The cut is performed with continuously moving the laser beam under CNC control.
The Relationship Between Lens Used And The Thickness Of Cut
Laser cutting usually use laser beam with a lens which creates sufficient power to perform laser cut. The lenses used are defined by the distance from the lens to the focused spot. When the focal length is shorter, the spot diameter and depth of focus become smaller. The actual spot size is also depends on the raw beam diameter. As the beam diameter increases, the focused spot size is decrease. To perform laser cutting, it require a high power density, small focus spot with long depth of focus. This allows the laser to cut thicker materials.
For usual CO2 laser cutting system, the range of focal lengths is from 2 ½ inches to 10 inches. A 5 inch lens could cut half inch thick steel, while thin material sheet on require a shorter focal length which allow higher cutting speeds. More details can be done on the materials with laser cutting too.
The Flexibility Of Laser Cutting
Most of the laser cutting machine have 3 axis systems, which is X and Y the two dimensional positioning control, and Z axis the height control. There are two ways or performing X-Y movement, which moving the laser head or the work piece, sometimes it used both combinations. The popular way to perform laser cut is “flying optic”, which remain the position of workpiece, while the laser move in both X and Y axes as the motor move in fixed mass. It is easier to control and predict the process with using this method. In this case, there are no limitations on the sheet weight as the workpiece is not moving.
Another way to perform laser cutting is “fixed optic, where the laser head remains the position and the workpiece moved in X and Y axes. It is a good option for light weight materials, but the position accuracy will be a problem when the weight increases. The third option is also known as “hybrid system”, where the laser head moved in one axis, and the workpiece moved at the other axis. This is the further improvement of fixed optics, but it is still a difficulty for heavier weights materials.
In conclusion, CO2 lasers are well suited for cutting acrylic, which used for advertising display, signs, and etc. The result of laser cutting depends on several factors, which is the materials, the laser used, and the laser cutting machine. By using laser cutting for acrylic, it can produce crystal clear amd flame-polished inner edges, which add value to the products.