The Star Micronics ST-20 is an industrial-grade CNC Lathes & Turning Centers powered by the FANUC 31i-B5. a top spindle speed of 10,000 RPM, and a 3-axis kinematic layout. It supports standardized digital factory monitoring via MTConnect.
Star Micronics ST-20: triple-turret Swiss-type lathe, Ø20 mm (25/32 in) bar, 10,000 rpm main and sub-spindles, 350 mm stroke, FANUC 31i-B5.
| Standardized Parameters & Ratings | |
|---|---|
| Manufacturer (Brand) | Star Micronics (Japan) |
| Machine Type | CNC Lathes & Turning Centers |
| CNC Controller System | FANUC 31i-B5 |
| Number of Controlled Axes | 3-Axis Simultaneous / Positioning |
| Maximum Spindle Speed | 10,000 RPM |
| Spindle Motor Rating | 3.7 kW |
| Spindle Taper Interface | Standard |
| Automatic Tool Changer (ATC) | 3 Tool Stations |
| Approx. Machine Weight | 4,850 kg |
| Industrial IoT Protocol | MTConnect ANSI/MTC1.4 Compliant (Ethernet/TCP) |
| Max Machining Diameter | 20 mm (25/32 in) |
| Max Headstock Stroke Standard | 350 mm |
| Max Headstock Stroke Rmgb | 317 mm |
| Sub Spindle Speed | 10,000 rpm |
| Sub Spindle Power | 3.7 kW (continuous) / 5.5 kW (10min./60%ED) |
| Front Turret | 8 stations (max 3 tools per station, 12/16 mm shank) |
| Rear Turret | 8 stations |
| Back Turret | 8 stations |
| C Axis | Main and sub spindle |
| CNC Control | FANUC 31i-B5 |
| Machine Weight | 4,850 kg |
| Max Turning Diameter | ø20mm (25/32in) |
| Max Turning Length | 350mm (13-25/32in) |
| Max Spindle Speed | 10,000 rpm |
| Spindle Motor Power | 3.7 kW (continuous) / 5.5 kW (10min/60%ED) |
| Turret Stations | 8 stations (front), 8 stations (rear), 8 stations (back working) |
| Tool Capacity | Max. 3 tools/station |
| Cnc Control | Fanuc 31i-B5 |
| Headstock Stroke | 350 mm (13-25/32 in |
| Turning Tools | 3 tools/station |
| Bar Capacity | Ø20 mm (25/32 in) |
| Rapid Traverse | 30 m/min (for X1, X2, X3, Z1, Z2, Z3 axes) |
| Footprint | 2,988 × 1,720 × 1,845 mm |
Our best estimate for the Star Micronics ST-20 is $200,000 - $330,000. This is an estimate for a swiss-type lathes in this class, not a quote from Star Micronics; configuration, tooling, automation and installation move the final price substantially. A specific price can be requested at https://machinetoolindex.com/machines/star-micronics-st-20#price; the request is passed to Star Micronics or an authorised dealer.
The table lists three turrets of 8 stations each: front, rear and back working. Each station takes a maximum of 3 tools, and the front turret row gives the shank size as 12/16 mm. The table does not state a total tool count or how many stations can be driven.
Yes. Both are listed at 10,000 rpm with 3.7 kW continuous and 5.5 kW at the 10min/60%ED rating, and the C-axis row covers main and sub spindle. Back-end operations can be planned with the same cutting data as front-end ones.
350 mm (13-25/32 in) as standard. A second row gives 317 mm for the RMGB version; the table does not spell out the abbreviation. Maximum turning length is listed as 350mm (13-25/32in).
Bar size, speed and weight. The ST-20 takes Ø20 mm (25/32 in) bar at 10,000 rpm and weighs 4,850 kg. The ST-38 takes Ø38 mm (1-1/2 in) bar at 7,000 rpm with 7.5 kW continuous and weighs 6,250 kg. The ST-38 is listed with 10 stations and a maximum of 2 tools per station (16mm); the ST-20 with 8 stations per turret and up to 3.
Control is a FANUC 31i-B5. The rapid traverse row lists X1, X2, X3, Z1, Z2 and Z3 at 30 m/min, and C-axis is listed for main and sub spindle. No Y axis appears in the table, so check the specification if off-centre milling is needed.
