Of identical mechanical construction, save for their centre heights, the TOS SUI63 and SUI80 lathe were first offered during the early 1980s. Large and powerful machines, the two lathes took their Model names from the swing over their hardened beds, 630 and 800 mm respectively. Both shared a bed of identical dimensions - 500 mm wide - with distances between centres available for both of  1500, 2000, 3000 and 4000 mm. The lathes were able to take a workpiece between centres weighing up to 1600 kg at a recommended spindle speed of 18 r.p.m.
Other than the previously-mentioned differences in capacity, the two lathes were identical with the same headstock holding a 71 mm bore spindle with a metric 80 taper, a Camlock 8 nose fitting and 18 spindle speeds from 11.2 to 1800 r.p.m. Drive came from a 15 kW motor and incorporated a combined, hydraulically-operated brake/clutch unit,
Over the full spindle speed range 60 rates of longitudinal carriage feed from 0.06 to 1.55 mm/rev and 60 in traverse from 0.03 to 0.775 mm/rev were available. When restricted to spindle speeds in the range of 11.2 to 112 r.p.m., the longitudinal feed rates varied from 0.5 to 13 mm/rev and in traverse from 0.25 to 6.5 mm/rev.
Rapids, driven by a separate motor built into the apron, were provided as standard on both directions of feed - the rates being 4800 mm/min longitudinally and 2400 mm/min in traverse.
Screwcutting was arranged to provide 43 metric pitches from 0.5 10 160 mm, 40 English pitches from 40 to 0.125 t.p.i., 36 module from 0.25 to 48 and 42 Diametral from DP 80 to 0.375.
Equipped with a large No. 6 Morse taper, the tailstock spindle was 110 mm in diameter with a travel of 180 mm
The shortest bed SUI-63 weighed approximately 4950 kg and the equivalent SUI-80 5180 kg.  The full specification of the two lathes - and details of the various options - can be found below..