Star SR-20J

Est. $180,000 - $320,000 Specs verified 2026-10-03 · ellisontechnologies.com Updated 2026-10-03

Image: starcnc.com, Star Micronics

Key Specifications

Max Spindle

10,000 rpm

Rapid Traverse

35 m/min (X1, X2, Z1, Z2); 24 m/min

Spindle Power

2.2 kW (continuous) / 3.7 kW (10min./25%ED)

Max Turn Length

205mm (8in) Type C / Bar diameterx2.5 Type N

max machining diameter

20 mm (0.787 in)

max machining length

205 mm (8.07 in)

How much does the Star SR-20J cost?

Estimated price range

Est.$180,000 - $320,000

Our best estimate for a swiss-type lathe in this class — not a quote from Star Micronics. Configuration moves it a long way.

Overview

The Star SR-20J is a Swiss-type lathe for bar up to 20 mm (25/32 in), with Ø23 mm (29/32 in) listed as an option, and up to 9 axes including Y1, Y2, C1 and C2. Main and sub spindle are identical in the table: 10,000 rpm, 2.2 kW continuous and 3.7 kW on the 10min./25%ED rating.

Equal spindles change how a part is planned. On many sliding-headstock machines the sub spindle has a fraction of the main motor and the back end is kept to finishing. Here the back end can take the same cut as the front, and with both Y1 and Y2 in the axis list each side has its own off-centre capability. Operations can be moved from one side to the other to even out the cycle.

Turning length depends on the type. Type C is listed at 205mm (8in). Type N is listed as bar diameter × 2.5, a short-part arrangement in which the length follows the stock being run. The headstock stroke row gives 205 mm (8 in).

The turning row lists 6 tools, on 12mm shanks. Rapid traverse is 35 m/min on X1, X2, Z1 and Z2. The machine weighs 2,750 kg, measures 2,250 × 1,200 × 1,700 mm and needs a 10 kVA supply. The SR-20R IV Type A/B, on the same ø20mm (25/32in) bar, is listed with a 27-position tool station for 41 tools at 2,600 kg.

Full Specifications

Parameter	Value
Max Machining Diameter	20 mm (0.787 in)
Max Machining Length	205 mm (8.07 in)
Number of Axes	Up to 9 (including Y1, Y2, C1, C2)
Rapid Traverse Rate	35 m/min (X1, X2, Z1, Z2); 24 m/min
Machine Weight	2,750 kg
Power Consumption	10 kVA
Max Turning Diameter	ø20mm (25/32in)
Max Turning Length	205mm (8in) Type C / Bar diameterx2.5 Type N
Bar Capacity	Ø20 mm (25/32 in); Optional (OP): Ø23 mm (29/32 in)
Max Spindle Speed	10,000 rpm
Spindle Motor Power	2.2 kW (continuous) / 3.7 kW (10min./25%ED)
Turret Stations	6 tools
Tool Shank	12mm
Headstock Stroke	205 mm (8 in)
Sub Spindle Speed	10,000 rpm
Sub Spindle Power	2.2 kW (continuous) / 3.7 kW (10min/25%ED)
Turning Tools	6 tools
Floor Space Required	2,250 × 1,200 × 1,700 mm

Specifications sourced from ellisontechnologies.com (authorised dealer / distributor, not the manufacturer's own site) — verified 2026-10-03

Strengths & Limitations

Strengths

Sub spindle matches the main spindle: 10,000 rpm, 2.2 kW continuous and 3.7 kW (10min/25%ED)
Up to 9 axes, including Y1 and Y2 as well as C1 and C2
Bar capacity of 20 mm (25/32 in), with Ø23 mm (29/32 in) as an option
205 mm (8 in) headstock stroke
10 kVA supply requirement

Limitations

Type N turning length is limited to bar diameter × 2.5, against 205mm (8in) on Type C
6 turning tools are listed, where the SR-20R IV Type A/B has a 27-position station for 41 tools
The Ø23 mm (29/32 in) bar size is optional, not standard
The axis count is given as up to 9, not a fixed 9, so the delivered number depends on the configuration

Best For

Parts that need real cutting power on the back end: 2.2 kW continuous on the sub spindle Off-centre milling and drilling on both ends, using Y1 and Y2 Shaft work up to 205mm (8in) on Type C Short parts on Type N, within bar diameter × 2.5 Bar up to 20 mm (25/32 in), or Ø23 mm (29/32 in) with the option

Frequently Asked Questions

01 What is the difference between Type C and Type N on the SR-20J?

The table separates them by maximum turning length. Type C is listed at 205mm (8in). Type N is listed as bar diameter × 2.5. Type N therefore suits short parts, and Type C is the one for shafts. The table does not describe other differences between the types.

02 Is the sub spindle as strong as the main spindle?

Yes, in the listed figures. Both spindles run to 10,000 rpm and both are rated 2.2 kW continuous and 3.7 kW on the 10min./25%ED rating. Back-end operations can be planned with the same cutting data as front-end operations, which helps balance the two halves of a cycle.

03 What bar size does the SR-20J take?

The standard capacity is 20 mm (25/32 in). Ø23 mm (29/32 in) is listed as an option, marked OP in the table, so it has to be specified with the order. Check collet and guide bushing availability for the larger size at the same time.

04 How many axes does the SR-20J have?

Up to 9, including Y1, Y2, C1 and C2. A Y axis and a C axis on each side means milled and cross-drilled features can be placed off centre on both ends of the part. Because the row says "up to", confirm the axis list of the configuration you are quoted.

05 What are the installation figures for the SR-20J?

The footprint is 2,250 × 1,200 × 1,700 mm, the weight is 2,750 kg and the supply requirement is 10 kVA. The bar feeder is not included in those dimensions, so add its length to the layout before fixing the position.