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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", Jacot, Swiss, Swiss Universal (also called the English Mandrel) Bottum and Dracip. However, more modern examples can generally be divided into two groups - the lighter "Geneva" and heavier Webster Whitcombe (WW). The "Geneva" can be recognised by its round bed, with a flat machined along either the top (or, more commonly, the back) and nearly always supported on a single foot beneath the headstock. These lathes, invented in 1859 by Charles S. Moseley in the U.S.A., generally take 6, 6.5 or 8 mm collets and were designed for lighter, very high-precision work. However, the "WW" is considered by many to be the more versatile of the two - and hence the more popular and valuable. Also American in origin, the WW dates from around 1889 and 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 carries 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 all 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. The lathes are robust, yet not over-sized, made to the strictest standards and 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. 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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