The paper deals with the determination of the effect of controlled tool cutting edge preparation on AlCu4SiMg (EN AW - 2014) aluminium alloy machining process as well as on tool wear. To conduct the experiment, the authors have chosen longitudinal turning technology and cutting geometry of indexable cutting inserts marked CCGT 120408F-AL and proposed suitable cutting conditions. By controlled tool cutting edge preparation (brushing), the desired edge rounding of indexable cutting inserts of 0–5 μm, 10–15 μm and 20–25 μm has been achieved. Depending on the radius rn and the roughness of the cutting edge, the course of wear of the cutting inserts, the flow direction of the shaped material and its effect on the formation and size of the build-up were monitored during machining of the aluminium alloy.