Schaublin 125 CNC

The Schaublin 125 CNC is a small high-precision lathe with a 125 mm centre height over the bed, a 270 mm swing over the bed and a spindle that runs 0 - 5,000 min-1 with runout below 0.5 µm, axial and radial. Schaublin builds it in three versions, LT, RT and RTM, and several rows of the specification give one figure per version, so settle the version before reading the numbers.

X travel is 200 / 190 / 185 mm on diameter for LT / RT / RTM, and Z travel is 415 / 395 / 390 mm in the same order. Schaublin gives 270 mm as the recommended maximum turning diameter, but swing over the carriage is 115 mm, so anything that has to pass over the carriage is held to that. Bar work is smaller again: 24 mm with a B32 collet. The spindle nose is A2-4 on the RT / RTM or D1-3'' on the LT / RT.

The spindle is rated 7.5 / 11 kW and 43 / 84 Nm, continuous / intermittent. X and Z each have a 1.4 kW AC motor and ball screws of 20 x 5 mm and 32 x 5 mm, for 500 daN of continuous feed force, a 5 m/min cutting feedrate and 7.5 m/min rapids. Those are small numbers beside a production lathe, and the reason to accept them is in the accuracy rows: 5 µm positioning accuracy and 2 µm repeatability on X and Z to VDI /DGQ 3441, with a 0.0001 mm programmable increment.

Interpolation is X-Z-C. The C axis positions to ± 0.012° and repeats to ± 0.006°, with a 36,000 °/min rapid feed and a pneumatic spindle interlock of 69 Nm at 5 bar. The turret takes 8 tools in VDI20 axial holders with a 16 x 16 mm maximum shank, and 4 stations are live, running 0 - 5,000 min-1 at 0.55 / 1.1 kW and 1.8 / 3.5 Nm. That covers cross-holes, flats and small slots, not milling of any weight.

The machine occupies 1,830 x 1,260 x 1,700 mm and weighs 1,250 / 1,400 / 1,570 kg (LT / RT / RTM). It needs 400 V at 50 Hz, 19 A and 13 kVA, plus air at 5-6 bar. The control is a Fanuc 0i-TF PLUS with a 10.4" LCD.