Harrison Alpha 1550XS

The Harrison Alpha 1550XS marks the point where the Alpha range turns into a long-bed machine. It swings 554 mm (21.8 in) over the bed and is offered in four lengths, 1,500 / 2,000 / 3,000 / 4,000 mm (59.1 / 78.7 / 118.1 / 157.5 in) between centres. A 104 mm (4.1 in) spindle bore runs through a D1-11 camlock nose, and the spindle has 15 kW (20.1 hp) over 1 - 2,000 rpm.

Four metres between centres on a lathe that can still be worked by hand is a rare combination. It is the format wanted for hydraulic rods, rolls, drive shafts and pipe, where the batch size is often one and a skilled turner wants to feel the first cut before letting a cycle finish the job. The Alpha's manual and semi-automatic modes are built for that. Threads, tapers, radii and grooves can be set up through question-and-answer screens, without writing a program.

A 12 in (305 mm) chuck is listed. Swing over the cross slide is 370 mm (14.6 in), and the gap opens the swing to 830 mm (32.7 in) for work held close to the spindle. The 104 mm (4.1 in) bore is large enough to take much pipe and heavy bar straight through the headstock.

Long beds need support equipment, and most of it is optional: travelling and stationary steady rests, hydraulic tailstock and steady rests, a swarf conveyor and an auto indexing tool turret. The tailstock supplied as standard is manual. Colchester states the lathe is built to DIN 8605 toolroom accuracy standards.