Johnford SV-33H

A 50-taper spindle in an 850 mm machine is unusual, and that is the whole point of the Johnford SV-33H. It takes the SV-33 frame, with 850 mm (33.5 in) of X and 610 mm (24 in) of both Y and Z, and replaces the 40-taper head with a BT or CAT 50 spindle turning 60~6,000 rpm through a Hi-Lo gearbox.

The motor is rated 11 / 15 kW (14.8 / 20.1 hp), continuous and 30 min. Combined with a two-range gearbox this gives low-speed torque for face mills, large drills and big taps in steel and cast iron, work the 10,000 rpm SV-33 would do slowly. Johnford's option column offers 8,000 or 10,000 rpm cartridge spindles in BT, CAT or BBT 50, and separately notes that power larger than 11 / 15 kW is available with the Hi-Lo gear.

Tooling scales up with the taper. The standard armless changer holds 20 tools rather than 24. Each tool may be 125 mm (5 in) in diameter with the adjacent pockets filled or 250 mm (9.8 in) without adjacent tools, up to 400 mm (15.7 in) long and 15 kg (33 lb). A 400 mm tool under 610 mm of Z travel leaves limited daylight over a tall part, so long boring bars and tall fixtures should be checked together.

The table is the same 1,000 x 600 mm (39.4 x 23.6 in) casting with a 1,200 kg (2,640 lb) capacity. Machine weight rises to 7,000 kg (15,400 lb) and the listed dimensions are 2,680 x 3,420 x 2,978 mm.