Haas ST-15L

The Haas ST-15L is a long-bed two-axis lathe with a mid-size spindle: 32.5 in (826 mm) of Z travel and turning length, an 8.3 in (210 mm) chuck, 2.5 in (64 mm) of bar capacity and 20 hp (14.9 kW) at up to 4,000 rpm. X travel is 7.88 in (200 mm).

The nearest relative in length is the ST-10L, which has the same 32.5 in (826 mm) bed and the same 10,000 lb (4,536 kg) shipping weight but a 6.5 in (165 mm) chuck, 1.75 in (44 mm) of bar capacity and 75 ft-lbf (102 N·m) of torque. The ST-15L doubles that torque to 150 ft-lbf (203 N·m) at 500 rpm and opens the spindle bore to 3.5 in (88.9 mm). The ST-10L answers with 6,000 rpm.

A stiffer bar changes what a long bed is good for. A 2.5 in bar at full turning length is thirteen times as long as it is thick, where the ST-10L's 1.75 in (44 mm) bar is over eighteen. Shafts in that range still need a centre, and the table lists an MT3 tailstock with 44 in (1,118 mm) of manual body positioning, 3.8 in (95 mm) of hydraulic quill travel and quill thrust between 140 lbf (623 N) and 1,130 lbf (5,026 N). No steady rest is in the table.

Torque at 500 rpm lets the machine rough steel shafts at sensible depths; 4,000 rpm is enough for finishing at the diameters a 2.5 in bar produces but leaves small-diameter work short of surface speed. Axis thrust is 3,300 lbf (14,679 N) in both X and Z, and rapids are 1,200 ipm (30.5 m/min).

Maximum turning diameter is 12 in (305 mm), falling to 11 in (279 mm) with a BMT45 turret and 6.8 in (173 mm) with a VDI turret, and the turret row reads 12-station BOT. The crate is 158 × 70 × 81 in (401 × 178 × 206 cm). Haas lists a starting price of US$93,995.