Star Micronics SK-51 Type A

A new Star SK-51 Type A typically runs $250,000-$400,000 depending on configuration, tooling packages, and bar feeding system. As Star's largest Swiss-type platform with dual turrets and matched high-power spindles, it commands a significant premium. Used SK-51 machines are relatively rare on the secondary market due to the specialized nature of the applications.

The SK-51 offers Swiss-type advantages—sliding headstock for superior concentricity on long parts, simultaneous main and sub spindle operations, and the ability to complete parts in one cycle. A conventional turning center may offer more machining power and larger part capacity, but typically requires secondary operations for back-end features. The SK-51 is the better choice when part completion in a single setup justifies the investment.

The SK-51 Type A is primarily designed as a sliding headstock machine. Contact Star Micronics for specific guide bushing configuration options, as availability may vary by region and specification. The machine's 125mm machining length and 80mm part projection capabilities are designed around the sliding headstock configuration.

The SK-51 requires a heavy-duty bar feeder capable of handling 51mm (2-inch) bar stock. Options include the LNS Sprint 565, IEMCA Boss 552, and FMB Turbo 5-65. These larger bar feeders require additional floor space behind the machine. Star can recommend and integrate the appropriate bar feeder at time of purchase.

With 7.5 kW continuous spindle power and 5,000 RPM capability, the SK-51 handles steel, stainless steel, aluminum, brass, titanium, and engineering plastics at 51mm diameter. At 2 inches, the 5,000 RPM spindle provides approximately 800 SFM (245 m/min), which is adequate for most materials. Very hard alloys like Inconel may require reduced speeds and depths of cut.

Yes. Despite its size, the SK-51 is designed for production environments with bar feeding capability, parts collection, and the tool capacity to run extended unattended cycles. The dual 12-station turrets minimize the need for tool changes, and the matched spindle power supports aggressive cutting parameters that keep cycle times competitive.