Star Micronics SB-12R Type G

The Star Micronics SB-12R Type G is the 13 mm (33/64 in) machine in the SB range, a sliding-headstock lathe with 205 mm (8 in) of headstock stroke when run with a guide bush. Run without one, the stroke is bar diameter x 2.5, to a maximum of 30 mm. It weighs 1,750 kg and occupies 2,070 mm × 1,177 mm × 1,760 mm.

That choice between the two modes is the main planning question. With the guide bush the machine supports long, thin parts across the full 205 mm (8 in). Without it the bar is held only by the collet and the 30 mm ceiling confines the work to short parts such as pins, screws and connector bodies.

Front tooling is 6 tools at □12 mm or 7 tools at □10 mm, so the smaller shank buys one more position. The sleeve holder is a 4-spindle unit carrying 4 tools at the front and 4 at the rear, which is where drills, taps and boring tools for both ends of the part go.

The table gives the main spindle 2.2 kW continuous and 3.7 kW at 10min./25%ED, and the sub spindle 0.55 kW continuous and 1.1 kW at 15min./40%ED. The sub spindle is listed at 12,000 rpm. The main spindle row reads 6,000 rpm; it is unusual for a main spindle to be listed at half the speed of its sub spindle, so confirm that figure with the dealer before planning small-diameter work around it. Rapid traverse is 35 m/min on X1, Y1, Z1, X2 and Z2, and the control is a Fanuc 0i-TD.