Haas ST-20
Key Specifications
Max Spindle
Tool Capacity
Spindle Power
max swing
max cutting diameter
max cutting length
Overview
The Haas ST-20 is the workhorse of the Haas turning center lineup. With a 533 mm (21 in) swing, 330 mm (13 in) max cutting diameter, 572 mm (22.5 in) max cutting length, and a 63.5 mm (2.5 in) bar capacity through an A2-6 spindle, the ST-20 covers the sweet spot of mid-size turning work that represents the majority of job shop production.
Haas re-engineered the ST-20 platform from the ground up, dropping the footprint by 11% while bumping the drawtube bore to 63.5 mm (2.5 in), a 25% increase over the previous generation. The 14.9 kW (20 hp) spindle delivers 203 Nm (150 ft-lb) of torque at 500 RPM and tops out at 4,000 RPM. That's a solid torque curve for production work in steel, stainless, and aluminum without running out of power on heavy roughing passes.
Axis travels are 213 mm (8.4 in) in X and 572 mm (22.5 in) in Z, with rapid traverse at 24 m/min (945 ipm). The 12-station bolt-on turret handles any combination of OD and ID tools, with a hybrid turret option for shops wanting limited live tooling. The 210 mm (8.3 in) chuck provides solid workholding for both bar and chuck work.
The ST-20 is the platform that supports the entire ST-20 family, including the ST-20Y with Y-axis and live tooling. The base ST-20 strips away the Y-axis complexity for shops that purely need turning capability. At roughly $55,000-$85,000 configured, the ST-20 undercuts comparable Doosan Lynx 2600 and Okuma GENOS L3000-e machines by $15-30K.
The Haas NGC control, HFO dealer network, and the sheer installed base of ST-20 machines across North America mean parts, service, and programming support are never far away. This is the machine most shops buy when they need a reliable, mid-size CNC turning center at a sensible price. Specs sourced from Haas Automation published data.
Full Specifications
| Parameter | Value |
|---|---|
| Max Swing | 533 mm (21 in) |
| Max Cutting Diameter | 330 mm (13 in) |
| Max Cutting Length | 572 mm (22.5 in) |
| Chuck Size | 210 mm (8.3 in) |
| Bar Capacity | 63.5 mm (2.5 in) |
| Spindle Nose | A2-6 |
| Spindle Bore | 88.9 mm (3.5 in) |
| Max Spindle Speed | 4,000 RPM |
| Spindle Motor Power | 14.9 kW (20 hp) |
| Spindle Torque | 203 Nm (150 ft-lb) @ 500 RPM |
| X Axis Travel | 213 mm (8.4 in) |
| Z Axis Travel | 572 mm (22.5 in) |
| Rapid Traverse X | 24 m/min (945 ipm) |
| Rapid Traverse Z | 24 m/min (945 ipm) |
| Tool Capacity | 12-station BOT |
| 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
- Redesigned platform with 11% smaller footprint and 25% larger drawtube bore addresses the two most common complaints about the prior generation
- 21-inch swing and 13 x 22.5-inch cutting envelope covers the majority of mid-size turning work in a typical job shop
- 2.5-inch bar capacity handles the most common production bar stock sizes without stepping up to a larger, more expensive machine
- At $55-85K configured, undercuts comparable Doosan and Okuma mid-size lathes by $15-30K
- Largest installed base of any Haas lathe means abundant used parts, tooling, and programming resources
- Same platform as the ST-20Y, so upgrading to Y-axis capability later means familiar castings, manuals, and service procedures
Limitations
- 20 hp spindle can feel underpowered for aggressive roughing in 4140, stainless, or Inconel compared to the ST-25's 30 hp
- No Y-axis or live tooling on the base ST-20 means off-center features require a second setup on a VMC
- 4,000 RPM max spindle speed limits surface speed on small-diameter aluminum finishing compared to 6,000+ RPM competitors
- BOT turret lacks the rigidity of BMT tooling found on the Y-axis variants and competitors like the Doosan Lynx 2600
- Resale value drops faster than Japanese competitors, losing 35-45% in the first five years based on used market data
Best For
Frequently Asked Questions
01
Base price starts around $55,000. Adding tailstock, chip conveyor, tool probe, high-pressure coolant, parts catcher, and bar feeder interface pushes the configured price to $70,000-$85,000. Used ST-20 machines from 2018-2023 sell in the $30,000-$55,000 range. The ST-20 is one of the most commonly available used Haas lathes on the market.
02
If any of your parts require cross-holes, flats, hexes, keyways, or other off-center features, the ST-20Y with Y-axis and live tooling eliminates a second-op VMC setup and pays for itself quickly. If your work is purely turning, threading, and boring, the base ST-20 saves $20-30K and removes the complexity of Y-axis and live tooling maintenance.
03
The Doosan offers a stiffer casting, BMT tooling as standard, and a Fanuc control with wider third-party CAM support. The Haas costs $15-20K less and provides the NGC control that Haas shops prefer. For accuracy-critical work, the Doosan edges ahead. For value and ecosystem consistency, the Haas wins.
04
Haas re-engineered the castings for an 11% smaller footprint, increased the drawtube bore to 63.5 mm (2.5 in) — a 25% jump — and redesigned the chip evacuation geometry with a steeper wedge angle. The BMT-65 turret option became available on the Y-axis variant. Core spindle specs remained the same.
05
With a bar feeder, parts catcher, chip conveyor, and tool probe for automatic tool setting, the ST-20 can run unattended for extended periods on repetitive bar work. Most lights-out operations are limited by bar length and chip management rather than machine capability. A chip conveyor is essential for unattended running.
Videos
Haas Automation UK
Haas Automation UK
Haas Automation, Inc.
Haas Automation UK
HFO Trident Machine Group
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