Machine Comparison
Haas ST-28Y vs Haas ST-35Y
Haas Automation vs Haas Automation · Mill-Turn Machines
Summary
The Haas ST-35Y is the long-bed version of the ST-28Y Y-axis lathe. Both have 9.4 in (239 mm) of X and ± 2 in (± 51 mm) of Y travel, 4 in (102 mm) bar capacity, a 12 in (305 mm) chuck, 4,000 rpm live tools, 472 ipm (12 m/min) rapids and the same 3,200 rpm, 40 hp (29.8 kW) A2-8 spindle with 425 ft-lbf @ 325 rpm.
The ST-35Y turns 32.5 in (826 mm) long against 22.5 in (572 mm) and swings 13.75 in (349 mm) against 11.75 in (298 mm), with a 12-station BMT-65 turret. The ST-28Y has the faster sub-spindle, 6,000 rpm against 4,100 rpm, and weighs 10,860 lb (4,926 kg) against 14,300 lb (6,487 kg). Haas lists them at US$134,995 and US$151,995.
Specifications Comparison
| Specification | Haas ST-28Y | Haas ST-35Y |
|---|---|---|
| X-Axis Travel | 9.4 in (239 mm) | 9.4 in (239 mm) |
| Y-Axis Travel | ± 2 in (± 51 mm) | ± 2 in (± 51 mm) |
| Z-Axis Travel | 22.5 in (572 mm) | 32.5 in (826 mm) ▲ |
| Max Turning Diameter | 11.75 in (298 mm) | 13.75 in (349 mm) ▲ |
| Max Turning Length | 22.5 in (572 mm) | 32.5 in (826 mm) ▲ |
| Bar Capacity | 4 in (102 mm) | 4 in (102 mm) |
| Chuck Size | 12 in (305 mm) | 12 in (305 mm) |
| Max Spindle Speed | 3,200 rpm | 3,200 rpm |
| Spindle Power | 40 hp (29.8 kW) | 40 hp (29.8 kW) |
| Spindle Torque | 425 ft-lbf @ 325 rpm (576 N·m @ 325 rpm) | 425 ft-lbf @ 325 rpm (576 N·m @ 325 rpm) |
| Spindle Taper / Nose | A2-8 | A2-8 |
| Sub-Spindle Speed | 6,000 rpm ▲ | 4,100 rpm |
| Live Tool Speed | 4,000 rpm | 4,000 rpm |
| Tool Capacity | 12 | 12 |
| Rapid Traverse | 472 ipm (12 m/min) | 472 ipm (12 m/min) |
| Machine Weight | 10,860 lb (4,926 kg) | 14,300 lb (6,487 kg) |
| Published List Price | US$134,995 | US$151,995 |
Advantages
Haas ST-28Y
- 6,000 rpm sub-spindle against 4,100 rpm
- Lower published list price, US$134,995 against US$151,995
- Lighter at 10,860 lb (4,926 kg) against 14,300 lb (6,487 kg)
Haas ST-35Y
- 32.5 in (826 mm) turning length against 22.5 in (572 mm)
- 13.75 in (349 mm) max turning diameter against 11.75 in (298 mm)
- 12-station BMT-65 turret
Verdict
The spindle and bar capacity are the same, so buy on part length. The ST-35Y suits pump shafts, drive shafts, cylinder components and long tubular oil and gas parts that need 32.5 in (826 mm) of turning length along with milled features. The ST-28Y suits flanges, couplings and heavy fittings within 22.5 in (572 mm), where its 6,000 rpm sub-spindle helps on back-end work and it lists at US$134,995.