Hydrostatically guided Starrag machine achieves unprecedented metal removal rate

22 January 2026

The Starrag S1250 HD 5-axis machining centre with hydrostatic guides is ideal for titanium machining thanks to its exceptional rigidity and damping. The machine achieved almost unbelievable results in performance-testing cuts carried out by Starrag at its main plant in Rorschacherberg. Using a carbide ‘Cylindrical Endmill Cutter Ø40 R1.24’ with 18 teeth that was developed in-house by Starrag and designed for high-performance cutting (HPC), the cutting specialists achieved a metal removal rate of 1,516 cm3/min. Starrag estimates this is potentially a world record in titanium machining.

Even the prototype of the Starrag S1250 HD proved to be a very efficient machine for cutting titanium structural components. Two years ago, in roughing tests, the machining centre with hydrostatic guides achieved up to three times the material removal rate of the Starrag STC 1250 version with roller bearings. The improved damping and dynamic performance also ensured excellent precision and surface quality during finishing.

For the series-produced machine, the Starrag engineers made a few additional modifications to further increase removal rates and reduce tool wear. As the most critical factors in this context are the rigidity and damping of the machine, the structure of the machine bed and the column was made even more rigid. The engineers also managed to increase the contact surface of the hydrostatics, thereby increasing rigidity and damping.

Another modification concerned the rotary table, which is now designed as a gearbox version. With an enormous torque of 25,000Nm and a clamping torque of 32,000Nm, it perfectly meets the requirements of titanium machining. In addition, the tried-and-tested, compact swivel milling head was enlarged on one side. This creates space for a 50% stronger A-axis with 12,000Nm of torque and 20,000Nm of clamping torque while retaining excellent accessibility.

In terms of work spindle, the Starrag S1250 HD uses Starrag's own robust 53kW gear spindle, which provides 1,600Nm of torque and a speed of 4,500rpm. A new feature here is the HSK-B160 interface, which ensures high tool rigidity thanks to its large contact surface. This is important for large cutting depths – especially for tools with a wide overhang.

With this interface, the Starrag S1250 HD is already equipped for future requirements. That's because modern processes for producing near-net-shaped blanks are likely to reduce the amount of roughing that is performed. The focus then shifts to the challenge of entering the complicated and deep cavities with tools up to 500mm long and producing a high level of performance there. These kinds of tools are optimally supported by the large flat contact area of the HSK-B160 holder.

The fact that the new Starrag S1250 HD concept is a hit is confirmed, not least by the order from Airbus for its Varel site. The company has already ordered five machines.