Machine Comparison
Haas ST-25Y vs Haas ST-28Y
Haas Automation vs Haas Automation · Mill-Turn Machines
Summary
The Haas ST-25Y and Haas ST-28Y are both from Haas Automation's mill-turn machines lineup, making this a common upgrade or lineup decision for shops already invested in the Haas Automation ecosystem. The Haas ST-25Y leads in max spindle speed (3,400 RPM vs 3,200 RPM). The Haas ST-28Y leads in spindle power (29.8 kW (40 hp) vs 22.4 kW (30 hp)). The Haas ST-28Y leads in chuck size (305 mm (12 in) vs 254 mm (10 in)). The Haas ST-28Y shows specification advantages in 10 categories, though the Haas ST-25Y may still be the better choice depending on your shop's specific needs and the type of work you run. Both machines are proven performers in production environments and represent solid investments for shops in the market for a mill-turn machine.
Specifications Comparison
| Specification | Haas ST-25Y | Haas ST-28Y |
|---|---|---|
| Max Spindle Speed | 3,400 RPM ▲ | 3,200 RPM |
| Spindle Power | 22.4 kW (30 hp) | 29.8 kW (40 hp) ▲ |
| Spindle Torque | 407 Nm (300 ft-lb) @ 500 RPM | 542 Nm (400 ft-lb) @ 500 RPM ▲ |
| Tool Capacity | 12-station BMT-65 turret | 12-station BMT-65 turret |
| Chuck Size | 254 mm (10 in) | 305 mm (12 in) ▲ |
| Bar Capacity | 76 mm (3.0 in) | 102 mm (4.0 in) ▲ |
| Control | Haas Next Generation Control (NGC) | Haas Next Generation Control (NGC) |
| Max Cutting Diameter | 349 mm (13.75 in) | 406 mm (16 in) ▲ |
| Max Cutting Length | 584 mm (23 in) | 711 mm (28 in) ▲ |
| Max Swing Over Front Apron | 806 mm (31.75 in) | 838 mm (33 in) ▲ |
| Max Swing Over Cross Slide | 527 mm (20.75 in) | 559 mm (22 in) ▲ |
| Spindle Torque Optional Gearbox | 1,356 Nm (1,000 ft-lb) @ 150 RPM | 1,898 Nm (1,400 ft-lb) @ 150 RPM ▲ |
| Spindle Nose | A2-6 | A2-8 |
| Spindle Bore | 89 mm (3.5 in) | 105 mm (4.13 in) ▲ |
| Price Range | $105,000 - $130,000 ▲ | $110,000 - $140,000 |
Advantages
Haas ST-25Y
- Higher maximum spindle speed of 3,400 RPM enables faster cutting on aluminum and non-ferrous materials
- More competitive pricing at $105,000 - $130,000 compared to $110,000 - $140,000
- Backed by Haas Automation's dealer and service network for parts and support
- Production bar work in stock up to 76 mm (3.0 in) diameter with secondary milling operations
Haas ST-28Y
- More spindle power at 29.8 kW (40 hp) for aggressive material removal in harder materials
- Superior spindle torque at 542 Nm (400 ft-lb) @ 500 RPM vs 407 Nm (300 ft-lb) @ 500 RPM
- Superior chuck size at 305 mm (12 in) vs 254 mm (10 in)
- Superior bar capacity at 102 mm (4.0 in) vs 76 mm (3.0 in)
- Superior max cutting diameter at 406 mm (16 in) vs 349 mm (13.75 in)
Verdict
The Haas ST-28Y edges ahead on specifications in this comparison, particularly in Spindle Power and Spindle Torque. However, the Haas ST-25Y remains competitive and may be the better choice depending on price, dealer support in your area, or specific workholding and tooling considerations. Both are capable machines — the best decision comes from running your actual parts and evaluating total cost of ownership including tooling, training, and service.