Haas ST-15Y

The Haas ST-15Y is a short-bed Y-axis lathe for bar up to 2.5 in (64 mm). It has an 8.3 in (210 mm) chuck, 16 in (406 mm) of Z travel, ± 2 in (± 51 mm) of Y and a 20 hp (14.9 kW) main spindle limited to 4,000 rpm. Live tooling is BMT45, also at 4,000 rpm.

On paper it is the ST-10Y with a larger spindle. The ST-10Y shares the 16 in (406 mm) of Z, the 7.88 in (200 mm) of X, the Y travel and the 11 in (279 mm) maximum turning diameter, but stops at 1.75 in (44 mm) of bar and 75 ft-lbf (102 N·m) of torque. Here the bore is 3.5 in (88.9 mm) on an A2-6 nose and torque is 150 ft-lbf (203 N·m) at 500 rpm. Shops running mostly steel bar between the two capacities have a clear reason to pick this one; shops running small brass or aluminium parts will miss the 6,000 rpm of the ST-10Y.

Bar parts with milled features are the natural job. The Y stroke is wider than the largest bar, so a flat, hex or slot can be cut across the full section without re-indexing. The C axis positions to 0.01°, interpolates at up to 60 rpm on a 5 hp (3.7 kW) rating, and locks with a 13.9 in (353 mm) brake that holds 250 ft-lbf (339 N·m).

If the part is to come off complete, look at the sub-spindle rows in the table: a 5.3 in (135 mm) chuck on an A2-5 nose, 6,000 rpm, a 1.5 in (38.1 mm) bore and a chuck throat 1.3 in (33 mm) wide by 1.37 in (34.8 mm) deep. Synchronised speed is listed at 4,800 rpm, above the main spindle's limit, so a pick-off can happen at any main spindle speed. The throat is smaller than the bar capacity of the main spindle, so larger parts are held in the jaws without passing into the sub-spindle. Ask Haas whether the quoted machine has the sub-spindle or the MT3 tailstock that the table also lists.

Rapids are 472 ipm (12 m/min) in X and Y and 1,200 ipm (30.5 m/min) in Z; thrust is 2,400 lbf (10,676 N), 2,300 lbf (10,231 N) and 3,700 lbf (16,458 N) respectively. The machine ships at 7,900 lb (3,583 kg) on a 126 × 70 × 81 in (320 × 178 × 206 cm) pallet. Haas lists a starting price of US$108,995.