Hessapp "Titan" Fine-Turning Lathe
Quite unlike any of the remarkable CNC machines now being manufactured by Hessapp, their "Titan" fine-turning lathe was a development of an already proven design by UNION-WERK A. G., a machine-tool manufacturer based in Mittweida, Saxony. In no sense a conventional, general-purpose lathe, the 7.5" and 7.875" centre height Titan - like the Dutch Hembrug Ergonomic - was intended for the use of diamond or other exotic tooling in a precise, rigid set-up that allowed very hard materials to be finished in a single operation. It was possible that, with the right combinations of workpiece and cutting tool materials, rotational speed and rate of cutting, to achieve both the dimensional accuracy and fine surface finish commonly achieved by conventional cylindrical grinding. The makers guaranteed that, for workpieces whose dimensions did not exceed a diameter of 100 mm (4") and a length of 100 mm (4"), an eccentricity not exceeding 0.002 mm (.00008") could be achieved - and that with the job being turned unsupported. Even at this degree of accuracy (and depending upon the material being cut) a fine-feed rate of up to a maximum of about 0.5 mm (0.20") per revolution could be set.
To achieve this rate of work and level of accuracy, the lathe was designed to be extraordinarily rigid and, to reduce vibration, all rotating parts were statically and dynamically balanced.
Mounted on a large, closed box section base and massively built, the hardened and ground-finished bed was cast in a close grained cast iron and supported at short intervals along its length. Separate prismatic and flat ways were provide for the saddle and tailstock. The makers pointed out that the machine should be installed on the ground floor, set upon suitable rubber or metal-bonded rubber blocks and free from the effects of vibration from traffic or other machines tools in close proximity.
The Titan was available in three models:
- with a headstock at both ends of the bed for automatic work cycles and mechanical hand controls for setting the machine (Fig. 1).
- a single-headstock model (Figs. 2 and 3) with mechanical hand controls for the longitudinal and transverse feeds
- a single-headstock model with an automatic work cycle and mechanical hand controls for setting the machine (Figs. 4 and 5).
Special models, used as single-purpose machines and set up according to the wishes of a customer, could also be provided.
The specification of the Titan was comprehensive and had obviously been given considerable thought and subjected to extensive experimentation, full details can be found below.