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There are several designs and types of lathe intended for use by watchmakers, some dating back to the late 1700s and including specialised models - for example, "fiddle" lathes; "steel turns", with two dead centres fixed and able to be slid along a rectangular bar; the Jacot, with two fixed dead centres formed as one with a "bed"; the Swiss Universal, also called the English Mandrel and the first lathe with a 'live' i.e. rotating spindle; the Bottum, an American version of the Swiss Universal, and the Dracip, a lathe with live and dead centres formed in one piece with a bed whose centre section was cut away to create a flat surface upon which to mounted a T-rest.
More modern lathes for watchmakers can generally be divided into two groups - the lighter "Geneva" and heavier Webster Whitcombe (WW) types. The "Geneva" can be recognised by its round bed, with a flat machined along either the top (or, more commonly, the back or both front and back faces) and usually supported on short-bed versions by a single foot beneath the headstock or, on the rarer long-bed tyres, by a foot at each end.
One of the most critical developments in the design of the lathe for watchmakers was a patent granted on October 19th, 1858 by George W. Daniels and Mr A.Fuller, both residents in the watchmaking and precision engineering centre of Waltham. The patent described the first hollow-spindle type of lathe that allowed the use of high-precision, draw-in collets, or 'chucks' and 'split chucks' as they were initially called. Daniels and Fuller did not manufacture the lathe, but one Charles Moseley - also then a resident of Waltham - did, and it is to him whom the idea was wrongly credited for so very long. The writer was always puzzled by the fact that although Moseley had eleven other, later, patents ascribed to him, the breakthrough one for hollow-spindle lathes was not. It was only when the writer was searching though patents relating to watch lathes that he came across the coincidence of dates and locations - 1857 to 1858 being the accepted time frame in which Moseley first made the lathe, and the Patent of 1858. If we include the time necessary from the idea's inception to the development of prototypes, experiments with different materials and the possibility of pre-production examples being made in the early months of 1858, this matching of dates appears significant. Did Moseley take up a licience to use the patent - or buy it outright? If so, the latter must be the more likely as it appears to have been used exclusively by him until its expiry 20 years later.
American in origin, the WW type of lathe dates from around 1889. It usually has a centre height, in standard form, of exactly 50 mm - though very occasionally 65, 70 mm and other figures are encountered. Of heavy construction, the bed is formed with a 37 mm-wide flat on the top, a 60-degree bevel along each edge and a headstock fitted with a spindle to accept 8, 10 mm or 12 mm collets (though ones to take odd, in-between sizes have also been discovered).
Of the very many types and models made, experienced users of these lathes generally concur that amongst the very best in terms of quality and usability are those WW models fitted with ball-bearing spindles made by the American companies Levin and Derbyshire. These lathes are robust, yet not ovesized and made to the strictest standards of accuracy. They are able to run continuously at very high speeds with absolute reliability and also, if necessary, take deep cuts. However, many users are certain that lathes with plain "cone" bearings can, when correctly set up, perform just as well. Hence, when buying a used lathe, the choice often comes down not to a particular make or specification, but balancing the condition, the range of accessories included and, of course, the price. Hence, when buying a used lathe, the choice often comes down not to a particular make or specification but to balance the condition, the range of accessories included and, of course, the price. If you seek to buy a watchmaker's lathe, the writer advises buying one as well equipped as possible, preferably in the maker's fitted wooden box and with as few missing accessories as possible. It will, of course, cost more but, if cared for, be a much more reliable investment.
Among exceptions to the Geneva and WW types are a variety of unusual and interesting machines, including a range of fine lathes by G.Boley, these being manufactured from the middle 1800s to the early 1900s with either a triangular-form bed or an "in-between" design (which did not catch on) where the bottom of the bed was semi-circular in form and the top triangulated or "bevelled". Also available have been slightly larger lathes with triangular beds such as Glashutte, H.Strube & Fils together with unknown makes from the former East Germany and - though they might be considered as being too large - an unknown model from France and the Dalgety.
Larger than the WW type are what might be called "toolmakers' or "bench precision" lathes: these vary in size from the Schaublin 65 and 70 (the latter types being one of the most popular and frequently-encountered machines in the professional watchmaker's workshop), the Pultra 15/90 and larger examples such as the Schaublin 102, American Watch Tool Company, Arrow, B.C.Ames, Bausch & Lomb, Bergeon, Benson, Boley, Bottum, Boxford, B.W.C., Carstens, Cataract, Cromwell, Crystal Lakes, CVA, Derbyshire, Elgin, Hardinge, Hjorth, Juvenia, Karger, Leinen, Levin, Lorch, Mikron, W.H.Nichols, Potter, Pratt & Whitney, Rambold, Rebmann, Remington, Rivett, Saupe, See (FSB), Sloan & Chace, Smart & Brown, T & L.M., U.N.D., Van Norman, Wade, Waltham Machine Works, Weisser, Wolf Jahn and (though now very rare), Frederick Pearce, Ballou & Whitcombe, Sawyer Watch Tool Co., Engineering Appliances, Fenn-Sadler and the "Cosa Corporation of New York." While useful machines in a precision workshop they are outside the scope of this article - but further information can be found here.
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