The innovative R-test system from measurement specialist IBS Precision Engineering offers a fast and precise method of determining rotary axis location in multiple-axis machine tools, with results output as simple x, y and z coordinate readouts. It provides data analysis to ISO 230 machine tool testing standard and achieves sub micron accuracy without the intricate and painstaking procedures of traditional machine alignment and set-up methods. It is suitable for calibrating swivelling head as well as both 360° and limited-arc rotary table CNC machines, with offset errors for rotating axes computed either independently or in combination. The portable system consists of an MT-Check probe with interface unit, a stem-mounted precision 22mm diameter carbide Masterball, tool-holder with alignment unit and all necessary mounting tools. It is ideal for CNC machine users and builders alike and produces results in minutes without special operator knowledge or experience. The R-test offers both static and dynamic operation, with intuitive Windows-based software outputting readings quickly and conveniently to a laptop PC. Static calibration accurately measures axis location errors, while use in dynamic mode provides total machine calibration in 3D – reflecting full 5-axis operation.-