For CNC shops wanting a lathe with a greater bar capacity but not a larger footprint, Norwich-based Haas Automation Ltd (www.haas.co.uk) now offers a range of big-bore turning centres.

The newest — and smallest — addition to the company’s big-bore line is the ST-15. This has a 63.5mm-diameter bar capacity, a maximum cutting capacity of 356 x 406mm, and a swing over the cross slide of 406mm.

Also included are a 210mm three-jaw hydraulic chuck and a 12-station bolt-on turret. The ST-15’s spindle is rated at 20hp (203Nm of torque) and has a maximum speed of 4,000 rev/min; on-the-fly wye-delta switching gives constant power over a wide speed range for constant-surface-feed cuts. The A2-6 spindle nose has an 88.9mm bore, while 30.5m/min rapids and fast turret indexing reduce cycle times.

Standard equipment on the ST-15 includes: rigid tapping, a 15in colour LCD monitor and a USB port. Options include high-torque live tooling with a C axis, a belt-type chip conveyor, a tailstock with hydraulic quill, an automatic tool probe, and high-pressure coolant systems.

The ST-15 has been designed to be highly accurate and thermally stable, with the use of finite-element analysis optimising the machine’s structural rigidity while maximising both chip and coolant flow.