Machining using ultrashort laser pulses is vastly used in science, technology and medicine. However, how to use the expensive laser irradiation efficiently is an important and still open question. To find the highest ablation efficiency, laser processing parameters, such as: pulse repetition rate and fluence have to be optimised. Moreover, forming two-and-a-half-dimensional (2.5D) structures on curved surfaces is in high interest because of the applicability of bio-inspired functional surface mimicking. In this work, experiments were carried out to find the highest ablation efficiency by machining cylindrical copper samples at different pulse energies and repetition rates. Optimal parameters were used for blade-riblet structuring on a cylindrical copper sample. The calculated ablation efficiency corresponds well with the commonly known theoretical model and deviations were explained.