Star SR-20R II

The Star SR-20R II is the second-generation evolution of Star Micronics' SR-20R Swiss-type CNC automatic lathe, incorporating design refinements and performance enhancements that build on the proven SR-20R platform. As part of Star's standard-range (SR) series, the SR-20R II delivers premium Swiss-type capability in the 20mm bar class with a focus on high-rigidity machining, enhanced thermal stability, and improved production efficiency compared to its predecessor.

The SR-20R II features a main spindle reaching 10,000 RPM and a back spindle at 8,000 RPM, both with built-in motor designs optimized for the demanding duty cycles of high-volume Swiss production. With up to 8 axes including Y-axis capability, the machine handles complex multi-feature parts requiring off-center milling, angular drilling, and extensive backworking. Up to 25 tool positions including live tooling stations provide the tooling density needed for complete part machining in a single cycle.

The 'II' generation incorporates improvements to thermal management, structural rigidity, and control software that translate to tighter tolerances, better surface finishes, and longer tool life in production. Star's Motion Control System optimizes cycle times through intelligent multi-path coordination, and the hydraulic-free design reduces maintenance costs and environmental impact. The machine supports both guide bushing and non-guide bushing configurations for maximum application flexibility.

Star's continuous improvement philosophy is evident throughout the SR-20R II. From refined casting designs that improve vibration damping to updated control algorithms that reduce settling time, the second-generation machine delivers measurable improvements in precision and productivity. The Fanuc 31i-B5 control provides the processing power and memory needed for complex synchronized programs, and Star's programming environment simplifies the creation of multi-path operations.