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Painted in a strange, tiger-like, mottled yellow-and-black finish (known as "craquellee" in German) the astonishingly conceived and beautifully-made UWG Universal Multi-purpose Machine Tool was manufactured first by the Hommel Company in Mannheim, Germany, until the early 1970s and then, production levels having fallen to uneconomic levels, by "Hommel-Hercules" and Walter Foerster. The design, almost certainly dating from the 1930s, was by Hans Luce, then working at the Rheinmetall-Borsig company in Sömmerda. This original machine was adopted by the Swiss Meyer & Burger Company and marketed by them, through Astobe A. Stoeckle, as the Astoba. During WW2, Luce was employed at the German Rheinmetall-Werke (tanks & guns) factory and then in the immediate post-war period, struck out on his own with an engineering office in southern Germany. Here, he developed a sales and manufacturing contract with the Hommel company, an organisation he may previously have come across during his war-time work, Hommel having strong connections with the German military. Indeed, many of the later and larger UWG 2 machines now in private hands came originally from the country's air force. In German vernacular the machine was an "Eierlegende Wollmilchsäue" or, literally translated, "egg-laying wool-milk-pig" - a machine that could do everything. From its appearance it would appear to have been designed as the sort of "lathe" that would have found a ready home in a boat, mobile maintenance unit or the cramped workshop of a self-employed instrument or clock maker; even today a journey to remote seas in a small craft would be made much safer if a Hommel, together with a suitable supply of materials, was on board. The total number of machines made is not known; however, one manufactured in 1952 was stamped 650 and, should that represents a production number, would indicate yearly volumes at a relatively low level; if any reader with a knowledge of the company's background can provide further information, the author would be pleased to hear from them. Two models were made, the UWG1 (an early version of which is featured on these pages) and the much larger UWG2, a model readily identifiable by the 6 slots cut into the front face of its base plate; for a comparison, see the table at the bottom of this page. All but a few of the many accessories are transferable between the machines, so easing the problem of finding these desirable and expensive items. If any reader has a UWG2, and is able to provide a set of detailed photographs, or copies of the manufacture's literature, the writer would be very pleased to hear from them. A rectangular cast-iron plate 20-inches (500 mm) long, 6-inches (150 mm) wide and 3-inches (76 mm) deep formed the basis of the machine. At the back a 6-inch deep extension at the left-hand end carried a boss from which protruded an 18-inch long (457 mm) vertical steel bar; surprisingly, the machine was not intended to be fastened down, but instead rested on five small rubber-tipped feet each about the size of a door stop - one at each corner of the base plate with a fifth at the back directly underneath the heavy vertical column. By using the base and column to mount combinations of a headstock, tailstock, compound slide rest, T-slotted boring table, rotary table (and numerous other accessories) the assembly could be used as a plain-turning or screwcutting 3.5 inch (90 mm) centre height by 14 inches (360 mm) between-centres lathe, high-speed sensitive drill, vertical and horizontal miller, jig borer, shaper, gear cutter, grinder, engraver, slotter, metal saw or surface table. Because the machine was so well made, and the design so thoroughly considered (and the number and range of its swivel movements so great) the Hommel was able to accomplish many of its functions to the same standards as dedicated, stand-alone machines - its ability being limited only by its rather small size. In order to make the unit as compact as possible the base was made relatively shallow and hence there was insufficient room to reach in and tighten nuts to hold components in place; instead, a simple but ingenious (though crude-looking) system was employed whereby levers protruded though slots in the front face of the plate and tightened them in place by a powerful cam action. The headstock and tailstock, when in position for use as a lathe, were not locked by the eccentric levers but each fitted with a single, round headed bolt (with holes for a Tommy bar) that acted on a pair of T-nuts to draw them down onto the base. Two accurately-ground slots ran down the length of the bed plate to provided a location for the "base keys" of the other accessories - whilst various other holes, slots and tappings were provided in the top surface and left-hand face to allow as great a versatility in their alternative positioning as possible. The result of this most thoughtful and carefully-considered design was a system which allowed items not only to be mounted with great accuracy, but also attached, adjusted and removed very quickly - a great help when changing from one set up to another in order to work through a complex job that involved a sequence of turning, milling, grinding and drilling. Unfortunately, as with all multi-purpose machines, all was not perfect. The time taken to change from one set-up to another could be considerable, though if you were stranded on a desert island, or 2000 feet down in the Atlantic, that would not have been a concern. so long as the machine could do the job - it was never intended for mass production. The base was, for its intended task, rather light and the method of locating critical components has been found, in practice, not to be sufficiently accurate or secure. One rather more annoying problem was the position of the vertical column; this was too far to the left and its verical axis fell in front of the lathe spindle line. Another failing of the vertical miiling and drilling assembly was a tendancy to stick when moved and a lack of quill-feed graduations - making drilling and boring into blind holes difficult and requiring more time to be spend setting up of ancillary measuring equipment. Although not clear from the illustrations, the slides dispensed with a conventional gib strip and used instead a rather dangerous method of adjusting out slack: a saw cut was made close to the V edge, to allow some flex, and "gib-strip" adjuster screws used to "bend" the section inwards. Whilst the slides were well made, and closely fitted, careless handling of the screws, or undue wear and consequent overtightening, would cause the "flexi-bit" to break off, rendering the machine useless. Further comment from users of Hommel machines would be interesting Continued below:
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