Each Big-Bore spindle head features a compact, symmetrical design for thermal stability and rigidity.

For companies that want to turn bigger diameter bar but do have the space for a larger-footprint lathe, Haas Automation now offers a complete line of heavy-duty Big-Bore turning centers. Each of these versatile turning centers offers more power, a larger chuck, and greater bar capacity - without having to step up to the next larger machine.

Six Big-Bore models are available, with maximum capacities from 305mm x 533mm for the compact ST-25 to 648mm x 2032mm for the large-frame ST-45L, and two models with Y-axis capabilities.

Critically, for machines designed to accommodate large diameter parts, Haas ST lathes are based on extremely rigid, heavy-duty, cast iron bases, designed using finite element analysis (FEA) and endowed with reinforcement ribs, to give reliable accuracy and repeatability when taking heavy cut after heavy cut. Each Big-Bore spindle head features a compact, symmetrical design for thermal stability and rigidity, and a 45-degree wedge design greatly increases the tool-mounting envelope and improves chip flow.

The Haas ST-25 has a maximum capacity of 381mm x 533mm, with a 806mm swing over the front apron. The machine's A2-6 spindle has a 76mm bar capacity, and is equipped with a 254mm hydraulic chuck. The spindle is powered by a 22.4kW vector drive system, and turns to 3400 rpm. A 12-station bolt-on style turret is standard. 

The ST-25Y has the same footprint and spindle specifications as the ST-25, with a maximum capacity of 305mm x 533mm. The machine is equipped with a Y-axis that provides ±50.8mm of travel, and includes high-torque live tooling and a servo-driven C axis. A 12-station hybrid VDI/BOT turret is standard.

The Haas ST-35 has a maximum capacity of 533mm x 660mm, with a 806mm swing over the front apron. The machine's A2-8 spindle has a 102mm bar capacity, and is equipped with a 305mm hydraulic chuck. The spindle is powered by a 29.8kW vector drive system through a 2-speed gearbox, and turns to 2400 rpm. A 12-station bolt-on style turret is standard. 

The ST-35Y has the same footprint and spindle specifications as the ST-35, with a maximum capacity of 457mm x 584mm. The machine is equipped with a Y-axis that provides ±50.8mm of travel, and includes high-torque live tooling and a servo-driven C axis. A 12-station hybrid VDI/BOT turret is standard.

The ST-45 has a maximum capacity of 648mm x 1118mm, with a 876mm maximum swing over the front apron. The machine's A2-11 spindle has a 178mm bore, and accepts an optional 457mm hydraulic chuck (chuck and hydraulic union not included).

The spindle is powered by a 29.8kW vector drive system through a 2-speed gearbox, and turns to 1400 rpm. A 12-station bolt-on style turret is standard. The ST-45L is a long-bed version of the ST-45, with a maximum capacity of 648mm x 2032mm for nearly double the turning length. The ST-45L comes standard with a servo-driven tailstock. 

Standard equipment on all Haas Big-Bore turning centers includes rigid tapping, a 15" colour LCD monitor, and USB connectivity. Available options include a belt-type chip conveyor, hydraulic tailstock, automatic tool probe, an automatic parts catcher, high-pressure coolant systems, and much more.

Haas Automation's ST Big Bore CNC lathes are serious machines for serious cutting. As with the Haas Automation DS dual spindle CNC lathes, the new ST machines benefit from many, productivity enhancing feature upgrades, including greater tool clamping force, quicker indexing, and increased C-axis torque (for machines equipped with optional live tooling), compared to previous models.