Star Micronics SR-20R IV Type A/B

Est. $200,000 - $350,000 Specs verified 2026-10-03 · ellisontechnologies.com Updated 2026-10-03

Image: starcnc.com, Star Micronics

Key Specifications

Max Spindle

10,000 rpm

Tool Capacity

41 tools

Rapid Traverse

35m/rpm (X1, X2, Y1, Z1, Z2), and 15m/rpm (Y2)

Spindle Power

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

Max Turn Length

205mm (8in)

max machining diameter

20 mm (25/32 in)

How much does the Star Micronics SR-20R IV Type A/B cost?

Estimated price range

Est.$200,000 - $350,000

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-20R IV Type A/B is a Swiss-type lathe for 20 mm (25/32 in) bar whose defining figure is tool capacity: a 27-position tool station that holds up to 41 tools. Main and sub spindle are matched at 10,000 rpm, 2.2 kW continuous and 3.7 kW on the 10 min/25% ED rating, and the standard headstock stroke is 205 mm (8 in).

The gap between 27 positions and 41 tools tells you that some positions carry more than one tool. The fixed part of the count is spelled out. Turning tools number 7, with 5 on the front on 12 mm shanks and 2 on the rear, and there are 3 cross milling tools. The table does not itemise the rest, and the mix is a matter of which holders are ordered.

A capacity like this pays off in two situations. One is a part with many small features, where every drill, tap and mill stays in the machine. The other is a shop that leaves two or three jobs tooled up at once and changes over by program instead of by spanner.

Guide bush choice affects stroke: the standard figure is 205 mm (8 in), and the RMGB arrangement is listed at 160 mm. The machine weighs 2,600 kg and measures 2,334 × 1,200 × 1,700 mm. The SR-20J, also ø20mm (25/32in) with the same spindle figures, lists 6 tools in its turning row and weighs 2,750 kg.

Full Specifications

Parameter	Value
Max Machining Diameter	20 mm (25/32 in)
Max Headstock Stroke Standard	205 mm (8 in)
Max Headstock Stroke Rmgb	160 mm
Sub Spindle Speed	10,000 rpm
Sub Spindle Power	2.2 kW (continuous) / 3.7 kW (10min/25% ED)
Tool Stations	27-position (up to 41 tools)
Front Tools	5 tools (12 mm) + 2 rear tools
Cross Milling Tools	3 tools
Machine Weight	2,600 kg
Max Turning Diameter	ø20mm (25/32in)
Max Turning Length	205mm (8in)
Bar Capacity	Ø20 mm (25/32 in)
Turret Stations	27-position
Tool Capacity	41 tools
Max Spindle Speed	10,000 rpm
Spindle Motor Power	2.2 kW (continuous) / 3.7 kW (10 min/25% ED)
Headstock Stroke	205 mm (8 in)
Turning Tools	7 tools (5 tools on the front + 2 tools on the rear (12 mm))
Rapid Traverse Rate	35m/rpm (X1, X2, Y1, Z1, Z2), and 15m/rpm (Y2)
Floor Space Required	2,334 × 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

27-position tool station holding up to 41 tools
Sub spindle equals the main spindle: 10,000 rpm, 2.2 kW continuous and 3.7 kW (10min/25% ED)
7 turning tools, 5 on the front and 2 on the rear, on 12 mm shanks
3 cross milling tools listed in addition to the turning tools
205 mm (8 in) standard headstock stroke
2,600 kg on a 2,334 × 1,200 × 1,700 mm footprint

Limitations

Headstock stroke falls to 160 mm with the RMGB arrangement
Bar size is 20 mm (25/32 in) with no option above it, where the SR-20J lists Ø23 mm (29/32 in) as an option
The table does not say what separates Type A from Type B
Reaching 41 tools depends on positions that hold more than one tool, so the usable count follows the holders ordered

Best For

Complex parts from 20 mm (25/32 in) bar that need many tools in one setup Keeping several jobs tooled at once across 27 positions Back-end work needing full spindle power: 2.2 kW continuous on the sub spindle Parts within a 205 mm (8 in) headstock stroke

Frequently Asked Questions

01 How many tools does the Star SR-20R IV hold?

Up to 41 tools in a 27-position tool station. Of these, 7 are turning tools on 12 mm shanks, 5 on the front and 2 on the rear, and 3 are cross milling tools. The table does not itemise the others. With more tools than positions, some positions must take more than one tool.

02 What is the difference between Type A and Type B?

The table gives one set of figures for both types and does not state how they differ. Bar size, spindle ratings, tool station and weight are common to the two. Ask the dealer which functions or axes separate Type A from Type B before choosing.

03 How do the two spindles compare?

They are listed the same. The main spindle is 10,000 rpm with 2.2 kW continuous and 3.7 kW on the 10 min/25% ED rating, and the sub spindle is 10,000 rpm with 2.2 kW continuous and 3.7 kW (10min/25% ED). Back-end cuts can be planned as heavily as front-end cuts.

04 What is the headstock stroke?

The standard maximum headstock stroke is 205 mm (8 in), and the maximum turning length is given as 205mm (8in). With the RMGB arrangement the stroke is listed at 160 mm, so long parts favour the standard guide bush.

05 How does the SR-20R IV compare with the SR-20J?

Both are ø20mm (25/32in) machines with 10,000 rpm spindles rated 2.2 kW continuous. The SR-20J lists 6 tools in its turning row, weighs 2,750 kg and offers Ø23 mm (29/32 in) bar as an option. The SR-20R IV has a 27-position station for up to 41 tools and weighs 2,600 kg.