Application of Self-Propelled Rotary Tools for Turning of Difficult-to-machine Materials

The paper presents some aspects of turning of difficult to machine materials with self-propelled rotary tools (SPRT). The main criterion of the rotary tools performance was the attainable surface quality, waviness and adhered chips. The dependence of the insert rotational speed on cutting parameters was also investigated. Original method of measurement of this speed was developed. Obtained results showed, that the speed is lower than theoretical, reported in literature. Stiffness and run out of the tools were measured. Cutting force measurements revealed substantial run-out of the rotating insert. Some important drawbacks and limitations of SPRT application were revealed.