George Nissel Contact Lens Lathe
Highly specialized in their field and intended for just one purpose, the production of contact lenses, the Nissel lathe was amongst the pioneers of the type. Although of very high quality and great accuracy, Nissel lathes of both the "spherical-turning" and "slide-rest" type - were of simple design and construction and make an interesting comparison with the very much more sophisticated and expensive ones made by the American Hardinge Company. This type of lathe is still produced, one of the leading manufactures in the early 21st century being Stirling Ultra Precision with a range of impressive models and all under CNC controlSome pictures are high-resolution and may be slow to load
The basis of the 85 mm centre height "slide-rest" Nissel lathe was a 24-inch long and 8- inch wide box-like iron casting with, secured by socket-headed screws to its top face, a steel plate upon which were mounted, in turn, separate slideways for the compound slide-rest assembly and headstock. As the headstock could be moved along the bed, the small, variable-speed DC motor was bolted in place beneath it, the drive being direct to the overhung end of the headstock spindle by a sort, Z-section V-belt.
The slide-rest plate was fixed with, at one end, a flange through which passed the feed screw - this being set parallel to the front face of the bed and supported at its far end by a bracket attached to the right-hand face of the stand. The operating handle was of the "balanced" type with the finger grip being able to rotate. Using the end bracket, feed screw and nut from an ordinary Myford ML7 lathe, the short-travel top slide was cut away on its top surface to allow the 4-way toolpost to sit low enough for the cutting tools to reach centre eight.
Avoiding all the complications of boring, honing and fitting-up a high-accuracy tailstock (as can be found, for example, on any Schaublin 70 lathe) the Nissel used an assembly with the spindle machined flat on top and held in place by a flat place screwed to the casting. Drive by a Victorian-style "drop-down" screw - the end of the spindle being fitted with a flange that fell below the spindle line, its lower section forming an abutment face for the feed screw to pass through.
The "spherical-turning" Nissel was of identical general arrangement, but with just a swivelling toolpost that allowed a radius to be formed on the end of the workpiece.
The background the Nissel company is interesting; born in Transylvania in 1913, George Nissel came to the UK in 1937 aged 25 after studying engineering in Hungary. He found a job at the optician and contact lens maker Theodore Hamblin, based at 18 Cavendish Square, London and, during the war was occupied making gun-sight lenses. During the course of his work, he met an engineer, George Grimes, who serviced the machines that Nissel used during his work. Forming a partnership, they started in business together in 1946 as G. Nissel & Co. in Siddons Lane, London, using a tiny 100 sq. ft. workshop and began to develop the first independent contact lens laboratory in the UK. As demand for contact lenses mushroomed, it was decided that they would make their not only their own but machinery required to produce them. Consequently, in 1947 and using George's engineering background, Nissel & Co. opened their first machine shop in 1947 where the first dedicated high-precision lathes and polishers for contact lens manufacture were made. By 1962 the machinery was being exported around the world and the firm manufacturing a range of ophthalmic items including artificial eyes, cosmetic haptics and corneal lenses. In, 1963 the first soft lenses made by lathe cutting were produced, perhaps first company to do so outside the country then the leading exponent of the craft, Czechoslovakia. At its peak G. Nissel & Co. Ltd. employed over 90 people - and still lives on as Cantor & Nissel based in Brackley and Hemel Hempstead..