Based in Yamato Koriyama, Japan, Mori Seiki has long been the maker of exceptionally high-quality CNC machine tools. Like almost all current makers of such machines, Mori-Seiki started by building conventional lathes, these too being of advanced design and built to a very high standard of accuracy. From what was a relatively small range, one of the most popular was the Type M, a group of lathe and powerful lathes available in three versions, the MS, MR, MH and the earlier ML. The success of these models is reflected in the fact that today (2023) they are still manufactured under licence by Whacheon in South Korea https://www.whacheon.com (and resemble several of the last-generation Japanese precision lathes such as Okuma/Dong Yang and Ikegai/Daewoo).
While the MS, MR and MH were all of identical mechanical design and construction, each of the many variants had numerous detailed modifications and alterations to its specification to suit its particular purpose. All qualified as "toolroom lathes" with their bed width being greater than the centre height. The MS had a swing of 435 mm and could be had with between-centres capacities of 650, 850 and 1250, the 850 mm model (as the 850G) having the option of a gap bed to swing 650 mm. The bed width was 352 mm and two motors were offered, one of 3.7 kW (5 h.p.) and the other 5.5 kW (7.5 h.p.). The MR was a larger machine with a swing of 520 mm and between-centres capacities of 100m 1500 and 2000 mm - all with the option (as the Model G) with a gap bed able to swing 750 mm. The bed width was 420 mm and, again, two motors were offered, one of 7.5 kW (10 h.p.) and the other 11 kW (15 h.p.). Both the MS and MR were equipped with disc brakes that allowed quick stops from high speeds.
The largest of the three was the MH, this being a very heavily built model with a swing of 610 mm and between-centres capacities of 1000 mm, 1500 mm, 2000 mm and 3000 mm - all with the option of a gap bed to swing 850 mm. The 3000 mm version had a bed width of 460 mm, the others 420 mm. Two motors were offered, one of 7.5 kW (10 h.p.) and the other 11 kW (15 h.p.), both equipped with a powerful brake to bring heavy jobs to a quicker stop. As an example of the careful attention to detail incorporated in these lathes, in addition to other modifications, the 3000 mm version was equipped with a larger diameter leadscrew (40 mm instead of the 38 mm of the MR) and a central bed support plinth.
The full specification of the MS, MR, MH and ML can be found below and on page 2.
Lathes earlier than these Mori-Seiki types are rare and, if you have one, or any sales literature (none appear to have been exported to the UK) the writer would be pleased to hear from you.