The aim of the master's thesis was the development, manufacturing, and testing of a CNC laser cutter for cutting various thicknesses of sheet metal. A 500 W fiber laser was used in the system's fabrication. The system was designed based on a linear positioning system with three axes, which not only guide the beam across the sheet metal but also allow adjustment of the z-axis, i.e., the distance between the laser cutting head and the work surface. The system is controlled via a 32-bit Makerbase MKS Robin Nano V3.1 controller using Marlin software. The controller enables us to generate the laser cutter's path by reading G-code generated in the laserweb software environment directly from the SD card. After manufacturing the laser cutter, we also tested the system. The top edge of the cut patterns was nice, but the bottom side had a dross. In the cutting tests of laser cutting of stainless steel with a thickness of 2 mm, we used a laser output power of 500 W and a nitrogen process gas pressure of 5 bar. The tests were carried out at different cutting speeds, which affected the amount and thickness of dross on the cutting edge. At a speed of 500 mm/min, a dense layer of dross, 0.5 mm thick, was formed. When we increased the speed to 800 mm/min, a slightly thinner layer of dross, 1 mm thick, appeared on the cutting edge. At a speed of 1000 mm/min, we observed a rather rare layer of dross, 2 mm thick.
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