Still in existence, the Benzinger Company is based in the Black Forest region of Germany and manufactures specialised machine tools for a variety of industries. With a factory in Unterreichenbach near Pforzheim (the jewellery and gold-smithing centre of Germany), Benzinger first appeared as a company in 1895, under the name Scheerle & Behner, but in 1917, after their name changed, they concentrated their energies on supplying such items as presses, and chain bending and brass & wire-rolling machines to the local jewellery industry. They also manufactured a range of precision bench lathes, with, unusually for the type, had a bed with a flat top and vertical edges the location of headstock, slide-rest assembly and tailstock being by bevelled and vertical faces machined into the full-length central slot. Known types manufactured include the DN, EN, FN, DM, EM and FM, these being supplied either on stands or for bench mounting - in the latter case known as the Models D/Dr. E/Dr, F/Dr with a draw-tube collet closer and D/Er, E/Er and F/Er with lever-action assembly. All versions were built on the same bed and with a 110 mm centre height and could be had with between-centres capacities of either 500 or 1000 mm; the spindle bore was available as 15, 20 or 25 mm. Like some versions of the Swiss Simonet and Schaublin precision bench lathes, the Bensinger could be had with a particularly neat, self-contained motor and countershaft unit. In the years around WW2 (1939 to 1945) the Company are known to have produced a number of special machines for cutting pocket and wrist watch cases. Although precision lathe production continued in post-war years, their name failed - in comparison with other established German makers of similar equipment such as  G. Boley, Lorch, and Leinen -  to become as well-known. However, in the jewellery field they became justifiably famous for offering a range of specialised lathes designed to produce and modify wedding rings - machines that could also be adapted to a variety of other precision machining processes. The ring blanks were cut from a tube of silver or gold and carried on an expanding collet, the opening and closing action of which was lever operated. The lathes always had two top slides, one lever operated and usually fitted with a conventional toolholder and the other able to be swung in a radius to form the curves along the ring edges. Some high-speed automatic versions were also manufactured and found a ready home, even at their very high price, in the workshops of larger jewellery manufacturers.
If you have a Benzinger ring lathe, or indeed any other type (or any further information about company's products), the writer would be very interested indeed to hear from you..

Benzinger lathe Types: DN, EN, FN, DM, EM and FM. Built on the same bed and with a 110 mm centre height the lathe could be had with between-centres capacities of either 500 or 1000 mm. The spindle bore (and hence collet capacity) was available as 15, 20 or 25 mm. This version was mounted on the maker's stand complete with a particularly neat, self-contained motor and countershaft system.

When supplied for bench mounting the lathe was produced as the Models D/Dr. E/Dr, F/Dr with a draw-tube collet closer and as D/Er, E/Er and F/Er with a lever-action assembly

Looking to have been made in the 1950s (and marked Made in West Germany,  this production version of the Benzinger has the same bed form as the ordinary versions but fitted with all-lever control of tool slides, tailstock and collet closer. Drive to the spindle was direct by V-belt from a motor mounted behind the headstock. Although front and rear tool posts are common on this class of lathe, this machine was unusual in having two top slides, one in front of the spindle line and one behind.

Above and below: a pair of more modern Benzinger lathes adapted for a special production process using pneumatically driven slides. That above is a Type  UD-11WK from 1995