The Haas ST-15 is a big-bore CNC lathe from Haas Automation, a USA-built turning center known for straightforward operation and broad service support that has made it a staple in job shops and production environments. This 2017 Haas ST-15 is a 2-axis CNC turning center with a 2.5" bar capacity, a 3.5" spindle bore, and an A2-6 spindle nose, packing big-bore capability into a compact machine. Haas rates the ST-15 for a maximum cutting diameter of 14" and a maximum cutting length of 16", with X / Z travels of 7.88" x 16" and 1,200 IPM rapids on both axes. The 20 HP vector dual-drive spindle reaches 4,000 RPM and delivers 150 ft-lb of torque, and its wye-delta switching provides a wide constant-horsepower band for constant surface speed cuts. Workholding is an 8.3" hydraulic 3-jaw chuck, and tooling runs on a 12-station bolt-on (BOT) turret that accepts any combination of OD and ID tools. The machine is run by the Haas CNC control, with rigid tapping and USB program transfer as standard Haas lathe features. For shops running bar work, shafts, fittings, and other round parts that exceed the bar capacity of small-bore lathes, the ST-15 is designed to handle that work without the floor space of a larger machine.
The ST-15 is the big-bore member of the Haas ST family, sharing its compact layout with the Haas ST-10, and the ST series is the current-generation successor to earlier Haas SL-series lathes such as the SL-10. Where the ST-10 is built around a smaller spindle and bar capacity, the ST-15 steps up to the A2-6 spindle nose, 3.5" bore, 2.5" bar capacity, and 8.3" chuck, opening the door to larger bar stock and heavier workpieces in nearly the same floor space. Compared with an older SL-series machine, the ST-15 is a current-generation design with a big-bore spindle package, a 20 HP vector dual-drive with wye-delta switching, and 1,200 IPM rapids. For a buyer, that means a meaningfully more capable machine, not just a newer one: bigger bar work, more torque at the spindle, and quick rapids in a lathe that fits where a small lathe used to sit.