# Capabilities and Limitations of Using Desktop 3-D Printers in the Laser Sintering Process  
[PERSON]  
1 Faculty of Mechanical Engineering, Centre for Advanced Manufacturing Technologies (CAMT/FPC), Wroclaw University of Science and Technology, 50-371 Wroclaw, Poland; [EMAIL_ADDRESS] (P.G. ); [EMAIL_ADDRESS] (G.Z. )1 Faculty of Mechanical Engineering, Centre for Advanced Manufacturing Technologies (CAMT/FPC), Wroclaw University of Science and Technology, 50-371 Wroclaw, Poland; piotr. a patent that protected LS machines expired, which resulted in more manufacturers entering the market of polymer laser sintering [6]. A relatively new category of devices, based on LS technology, is desktop solutions, which are characterized by their low purchase price (<EUR 25,000)--even tenfold lower when compared to industrial solutions. Although they are based on the same principles of operation as the industrial versions, they show differences in the complexity of individual systems, the quality of produced models, the stability of the process, and the variety of materials that can be used. This is especially the case when taking into account the noticeable differences in the obtained results of production between industrial and desktop devices--only the first ones are known to meet specific functional requirements. A few desktop 3D printers are currently available on the market, e.g., S1 (Sintratec, Brugg, Switzerland), Lisa (Sinterit, Krakow, Poland), SnowWhite (Sharebot, Nibionno, Italy), VIT SLS (Natural Robotics, Barcelona, Spain) and Red Rock (Red Rock 3D, Moscow, Russia). The main difference in the construction of desktop devices relates to the type of laser, the control system, and the size of the processing chamber [7] (Table 1). The use of a diode laser, instead of a CO\({}_{2}\) laser, significantly reduces the cost of the device, but the low radiation energy available for this solution is unsuitable for organic polymers in the spectral range. This requires special material mixtures that enhance energy absorption in order to reach an adequate level for melting a specific material [8]. The materials most commonly used for a desktop machine are PA 12 and flexible TPU/TPE. LS-desktop devices can not only be used for prototypes, but also for tooling. It is more and more noticeable that solutions of this type can be part of modular production systems that allow the production of end parts on a larger scale. [PERSON] et al. [9] described the development of a low-cost, open-source LS system (OpenSLS) using nylon and polycaprolactone (PCL). In [7], [PERSON] el al. consider the use of low-cost 3D printers based on LS technology to perform three-dimensional (3D) surgical modelling in reconstructive surgery. Regarding medical applications, an attempt was also made to manufacture orally disintegrating tablets based on two polymers: hydroxypropyl methylcellulose (HPMC E5, JRS PHARMA, Rosenberg, Germany) and vinylpyrrolidonevinyl acetate copolymer (Kollidon\({}^{\circledR}\) VA 64, BASF, Callanish, UK) mixed with paracetamol. A desktop 3D Printer (Sintratec Kit, Brugg, Switzerland) was used for this purpose [10]. However, a LS desktop is not only used in medical applications. Desktop solutions were considered in the production of spare parts for aviation. One scenario presented by [PERSON] et al. involved the use of Norge Ice 9 and Ice 1 (Norge Systems acquired by Prodways in 2015) [11]. [PERSON] et al. presented the analysis of the influence of gradient topology on the deformation process of the cellular structure, which was achieved based on a Lisa 3D printer and polyamide material [12]. To the best of our knowledge, no benchmarking of desktop laser sintering devices has been reported in the academic literature to date. The determination of the capabilities and limitations of desktop devices was conducted.