This paper describes benefits of close collaboration between technologists and analysts of machine tools. After all, any innovation in machine design can only be proven by producing components of required quality more economically. The combined expertise can be utilized especially in machining new materials, such as titanium, which are more difficult to machine. The decisive factor in optimization of the production process is the cost: cost of labour, machine and tools. The cost of tools is important and the paper proposes a new model of tool life, which is experimentally verified. The model allows determination of a combination of machining parameters for minimum cost. Increase in axial depth of cut could improve the removal rate but is limited by stability of the cutting process. That is why the paper proposes machining at very low speeds, where the stability limit is higher and the lowest cost can be achieved. At these low speeds it is beneficial to use not carbide but HSS tools.