In this thesis,a design of a portable measuring test rig is developed with the aim of measure the tangential force, the most characteristic component of the cutting force.This test rig can be used in different lathes without any large modification.The design is based on the lever law to transmit the tangential force to a piezoelectric senso rconnected to an amplifier, to a dataa cquisition system and to a computer to obtain the graph of the speed against the tangential cutting force.The sensor is preload using an original fixing screw of the lathe.The results show that the tangential force is measurable using the device. Due to the geometry, when the tangential force rises 100 N, the reaction in the sensor rises approximately 120 N. Using a preload in the sensor of 10 kN, with a tangential force of 500N, the piezoelectric sensor receive about 13 kN.