There is a currently a wide variety of 3D printers, based on the process of fused deposition modelling available on the market. The price can vary anywhere between €100 and €700. The aim of this Bachelor’s thesis was to present the process of improving the print quality of an affordable 3D printer, the Creality Ender 3, which is on a par with the higher priced Ultimaker 3D printer range. The theoretical part of the thesis covers the main features of printers and the products which will be used for comparison. It is followed by a description of all the problems of the Ender 3 3D printer and how we managed to solve them. Finally we will compare the results of the finished prints made on the Ender 3 and Ultimaker 3D printers, where we have shown that the modified Ender 3 printer can compare with the print quality of competitors like Ultimaker 2 and 3.