Haas ST-35

$85,000 - $120,000 Updated 2026-03-12

Key Specifications

Max Spindle

3,200 RPM

Tool Capacity

12-station BOT

Spindle Power

29.8 kW (40 hp)

max swing over front apron

806 mm (31.75 in)

max swing over cross slide

527 mm (20.75 in)

max swing over tailstock

584 mm (23 in)

Overview

The Haas ST-35 is the big-bore variant of the ST-30 large-frame platform, stepping up to a 29.8 kW (40 hp) spindle, 102 mm (4 in) bar capacity, 305 mm (12 in) chuck, and A2-8 spindle nose. It shares the ST-30's 806 mm (31.75 in) swing and 381 x 826 mm (15 x 32.5 in) cutting envelope but with substantially more power and bore capacity for heavy-duty turning.

The spindle delivers 576 Nm (425 ft-lb) of torque at 325 RPM, topping out at 3,200 RPM. The 117.3 mm (4.62 in) spindle bore comfortably handles the 4-inch bar capacity. Combined with the 12-inch chuck, the ST-35 handles large-diameter workholding that the ST-30's 10-inch chuck and A2-6 nose cannot accommodate.

Axis travels are 318 mm (12.5 in) in X and 660 mm (26 in) in Z with rapids at 24 m/min (945 ipm). Maximum thrust forces match the ST-30 at 18,238 N (4,100 lbf) in X and 22,686 N (5,100 lbf) in Z. Between centers is 762 mm (30 in) for tailstock-supported work. The 12-station bolt-on turret with 102 mm (4 in) boring bar rear clearance handles large boring tools without interference.

The ST-35 fills a specific production niche: shops running 4-inch bar stock and large-diameter chuck work on a large-frame platform that stays under $100K base price. It competes directly with the Doosan Puma 3100XLM and Mazak QT-300 in bore capacity while maintaining the Haas price advantage.

At roughly $85,000-$120,000 configured, the ST-35 delivers 40 hp and 4-inch bore on the proven ST-30 frame. The NGC control, HFO service network, and consistent Haas operator experience apply across the entire lineup. Specs sourced from Haas Automation published data.

Full Specifications

Parameter	Value
Max Swing Over Front Apron	806 mm (31.75 in)
Max Swing Over Cross Slide	527 mm (20.75 in)
Max Swing Over Tailstock	584 mm (23 in)
Max Cutting Diameter	381 mm (15 in)
Max Cutting Length	826 mm (32.5 in)
Between Centers	762 mm (30 in)
Chuck Size	305 mm (12 in)
Bar Capacity	102 mm (4 in)
Spindle Nose	A2-8
Spindle Bore	117.3 mm (4.62 in)
Max Spindle Speed	3,200 RPM
Spindle Motor Power	29.8 kW (40 hp)
Spindle Torque	576 Nm (425 ft-lb) @ 325 RPM
X Axis Travel	318 mm (12.5 in)
Z Axis Travel	660 mm (26 in)
Rapid Traverse X	24 m/min (945 ipm)
Rapid Traverse Z	24 m/min (945 ipm)
Max Thrust X	18,238 N (4,100 lbf)
Max Thrust Z	22,686 N (5,100 lbf)
Tool Capacity	12-station BOT
Boring Bar Clearance	102 mm (4 in)
Coolant Capacity	208 L (55 gal)
CNC Control	Haas Next Generation Control (NGC)

Specifications sourced from haascnc.com — verified 2026-03-28

Strengths & Limitations

Strengths

40 hp spindle with 425 ft-lb of torque handles aggressive roughing in steel, stainless, and alloy steels on large-diameter parts
4-inch bar capacity and 4.62-inch bore cover large-diameter tube and bar work the ST-30 cannot handle
12-inch chuck on A2-8 nose provides heavy-duty workholding for large-diameter parts without going to the ST-40's 15-inch frame
Same large-frame ST-30 platform with proven castings, giving shops the option to share tooling and fixturing
102 mm boring bar rear clearance handles large boring bars without turret interference
At $85-120K, delivers 40 hp and 4-inch bore at roughly half the price of comparable Japanese large-bore lathes

Limitations

3,200 RPM max spindle speed limits surface speeds on small-diameter work and aluminum finishing
Same cutting envelope as the ST-30 despite the larger bore, so maximum part dimensions do not increase
No gearbox option unlike the ST-30, relying solely on the 40 hp direct-drive for low-speed torque
Heavy 12-inch chuck assembly reduces acceleration and increases turret indexing settle time
BOT turret rigidity trails BMT tooling found on Y-axis variants and some competitors at this price

Best For

Large-bore production turning in 4-inch bar stock and tube for oil and gas, petrochemical, and process piping Heavy-duty chuck work on large flanges, housings, and pump components up to 381 mm (15 in) diameter Shops needing 40 hp and 4-inch bore on the large-frame platform without stepping up to the ST-40 Hydraulic cylinder manufacturers machining cylinders and valve bodies in large-diameter stock Contract manufacturers running a mix of large-bore bar and chuck work across multiple materials

Frequently Asked Questions

01 What does a new Haas ST-35 cost?

Base price starts around $85,000. Adding tailstock, chip conveyor, high-pressure coolant, and tooling pushes the configured price to $100,000-$120,000. Used ST-35 machines from 2016-2022 sell in the $45,000-$75,000 range depending on hours and condition.

02 How does the ST-35 compare to the ST-28?

Both offer 4-inch bar capacity and 40 hp spindles, but the ST-35 has a much larger cutting envelope at 15 x 32.5 inches versus the ST-28's 13 x 22.5 inches. The ST-35 also has a larger swing at 31.75 inches versus 21 inches. Choose the ST-28 for compact footprint with big bore. Choose the ST-35 when you need the larger work envelope.

03 Should I buy the ST-35 or the ST-40?

The ST-40 jumps to a 648 x 1,118 mm (25.5 x 44 in) cutting envelope, 15-inch chuck, and optional 55 hp with a 2-speed gearbox delivering 1,400 ft-lb of torque. If your parts fit within the ST-35's 15 x 32.5-inch envelope and 4-inch bore is sufficient, the ST-35 saves $30-50K. The ST-40 is the machine for truly large parts.

04 Can the ST-35 handle stainless steel and alloy steels?

Yes. The 40 hp spindle and 425 ft-lb of torque handle 304, 316, and 17-4 stainless at production feeds. Alloy steels like 4140 and 4340 are well within the machine's capability. The 12-inch chuck and A2-8 nose provide solid clamping for heavy cuts. For exotic alloys like Inconel, consider the ST-40 with 55 hp.