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This article deals with the adjustment of a 3D printer for laser engraving and material cutting. The print head can be fitted with a solid laser diode module, which achieves a compact size while retaining its useful power. Two paths lead to the use of such a concept. It is possible to equip the existing print head with a module, which also brings a number of disadvantages such as, for example, the reduction of the printing space or the need for a suitable mounting design. A more elegant solution is to consider this in the design of a 3D printer and design a system to exchange the print heads for 3D printing and laser engraving. Such a solution allows full utilization of the workspace and simple installation of the effector for the required type of work. According to the installed power of the laser diode, it is possible not only to engrave but also cut material such as thin wood, veneer or acrylic glass. The use of such a machine is not only for graphic elements but for the creation of various stencils, boxes or simple models, which can be made up of plastic-burning pieces. The laser module is controlled by a driver, which is designed for the device. This is connected to a 3D printer control board. It is, therefore, necessary for the control board to have at least two pins, which can be controlled after adjusting the control firmware. Most laser modules are normally equipped with an adjustable lens, which is used to concentrate the focus of a laser for the given distance against the worktop. Thus, the modified 3D printer can perform its function as a multi-purpose CNC machine, while a basic platform similar for both devices is used.

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Wire electrical discharge machining is an unconventional machining technology that is crucial in many industries. The surface quality of the machined parts is carefully monitored, but the condition of the subsurface layer also plays a crucial role, especially in case of defects occurrence such as cracks or burnt cavities. The subsurface layer of individual materials is affected differently due to wire electrical discharge machining. For this reason, this study was carried out focusing on a detailed analysis of transmission electron microscope (TEM) lamella made of Ti-6Al-4V titanium alloy, AlZn6Mg2Cu aluminum alloy, pure molybdenum, Creusabro 4800 steel, and Hardox 400 steel. The attention was first of all paid to the concentration and distribution of individual elements in the recast layer and also in the base material, which was often affected by wire electrical discharge machining. Further, a diffraction analysis was performed for each TEM lamella in the adhesive area and in the base material area. In order to assess the macro-effects on the machined material, the topography analysis of the machined surfaces and the morphology analysis were performed using electron microscopy.

Die-sinking electric discharge machining (EDM) is an indispensable technological operation, especially in the production of molds and all internal and external shapes and cavities. For this reason, the effect of machine parameter settings (open-voltage, pulse current, pulse on time, and pulse off time) on the machining of two types of steels, 1.2363 and 1.2343ESR, was carefully investigated using graphite or copper electrodes in 10 mm × 10 mm or 100 mm × 100 mm shapes. For this purpose, a two-level half factor experiment was performed with one replication at the corner points and two replications at the central points, with a total of 80 rounds. The subject of the evaluation was the topography and morphology of machined surfaces including a detailed analysis of surface and subsurface defects in the form of cracks including the creation of regression equations describing the probability of crack occurrence. Furthermore, a study of the local hardness change in the subsurface area was performed, and lamellas were also made and studied by transmission electron microscopy. It has been found that by using die-sinking EDM, it is possible to effectively predict the probability of cracking on machined surfaces and also on machine 1.2363 and 1.2343ESR steels with a very good surface quality of Ra 1.9 and 2.1 µm using graphite electrodes. These findings will ensure the production of parts with the required surface quality without cracks, which is a crucial aspect for maintaining the required functionality and service life of the parts.