The aim of this work is to present the construction of an extruder, the purpose of which is to extrude filaments of 1.75 millimetres in diameter, to meet the requirements of 3D printers. Used to manufacture filaments for commercial purposes, the extruder covers the mechanical structure, the operation of the direct current motor and the use of an Arduino® programmed to control the temperature in an open loop. The results obtained were satisfactory as the project was carried out, taking into account the optimum operation of the temperature control and motor torque, which are the key parts for good extrusion.