Johnford SL-40L

Shaft work is what the L adds. The Johnford SL-40L stretches the SL-40 to 1,000 mm (39.4 in) of Z travel and 900 mm (35.4 in) of tailstock travel, on the same 10 in chuck and 4,000 rpm, 11 / 15 kW (14.8 / 20.1 hp) spindle.

A metre between chuck and centre covers a wide class of parts: motor and pump shafts, spindles, rollers, long studs, hydraulic rods. They are slender relative to the Ø580 mm (Ø22.8 in) swing, so the light spindle drive of the 40 frame is less of a restriction here than it is on big-diameter chucking work. Cuts on a shaft are limited by deflection of the part long before they are limited by motor power.

Support is the thing to plan. The tailstock quill is Ø60 mm (Ø2.4 in) with 60 mm (2.4 in) of stroke and an MT#4 fixed centre, with an MT#3 rotary quill as an option. For shafts near the full length Johnford lists its own manual steady rests and hydraulic steady rests as optional accessories. A programmable hydraulic tailstock is optional too, and worth having when part lengths change often.

Compared with the SL-40 the bed is longer, 4,050 mm (159.4 in) overall, the machine is heavier at 5,500 kg (12,100 lb), and the Z servo motor is 3 kW. With the Y-axis fitted, Z travel is 900 mm (35.4 in). The next long machine in the range is the SL-60, which has 1,040 mm (40.9 in) of Z on the heavier 45° bed.