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Contimued: No backgear is fitted; instead, following modern practice (as on Hobbymat and Unimat lathes for example), a 4-step overhung pulley is fitted on the end of the headstock spindle driven either directly from the motor or, to obtain the full speed range, by running belts from the motor pulley to an idler pulley positioned below and then back up to the spindle pulley. It may even be that the headstock spindle pulley is intended to be reversed (with the changewheels removed for clearance) to obtain and even wider speed range. A jockey pulley (visible between the motor and intermediate pulleys) is provided to press against the back of the V belt to provide tension in the low speed range. A problem arises if the lathe was placed flat on a long bench: with the up/down adjustment of the idler pulley - to tighten the belt - is done from underneath the adjuster cannot be reached. The solution is to place the lathe so that it overhangs the edge of the bench - or fit the two crude wooden-block feet supplied by the makers. Though robust looking, the tailstock, contains a barrel with a miserly 30 mm of travel - and a hopelessly inadequate No. 1 Morse taper nose. Late machines have a No. 2 Morse taper, but no more travel, and a useless ¼" capacity drill chuck. As standard, the machine is very well equipped, being supplied with the accessories necessary to convert it into a tool grinder, a simple boring and milling machine (with a vertical-milling slide), a wood lathe, a 35 mm-depth capacity circular saw, a wood planer capable of machining material up to 85 mm wide and an "Alternating" saw. Besides the conversion equipment, a 3-jaw chuck, tailstock chuck, machine vice, drive dog and No. 2 to No 1 Morse taper adapter also accompany each machine together with a set of Carbide and Ti-Nitride HSS cutting tools, a decent tool kit, a set of changewheels to cut metric threads (from 0.2 to 2.5 mm pitch) and two dead and one rotating centres; of course, this accessory list is subject, of course, to the usual change without notice. The overall length has been seen listed at both 670 mm and 825 mm, the width 410 mm and the height 285 mm; when stripped, the basic machine weighs just 60 Kg whilst the accessory kit adds a further 30 to 35 Kg. In the early 1990s the lathe was priced at around US$800 - a comparative bargain considering the rigid construction and large number of standard accessories. Today, several versions of the lathe appear to be manufactured with the two main variants being an industrial "light-production" unit the other a conventional screwcutting centre lathe with a compound slide rest; both are very similar in overall construction but the industrial lathe has a lever-action, quick-release collet chuck and a six-station, bed-mounted capstan fitted as standard. The other models are (in so far as they can be translated): TN-ymb - a basic model with the minimum tool kit TN-ymby - the lathe fitted with several extra (unspecified) "universal devices and adaptations" TN-ym - complete with all the accessories except the "swivel head" and quick-release collet holder TN-ymr - a basic model with a quick-release collet holder and a bed-mounted capstan unit. TN-ymrp - another version with a quick-release collet holder and a bed-mounted capstan unit. Another little known machine of eastern European origin is the miniature TOS precision lathe which, whilst of a completely different design to the Russian machine, was also marketed some years ago with a vast accessory range and at a bargain price.. A Korean firm, the Dajoo Corporation, produced a very close copy of the Russian lathe under the model designation BV15. Details might still be available from the makers: In recent years a number of changes were incorporated in the original Russian model including moving the motor-direction switch to where the on/off switch was and the on/off push-buttons relocated around the RH side to the electrical box. The standard 3-jaw chuck became an 80 mm branded as a "Belarusa" (with some poor machining on the jaws). Both the motor and lower pulley set became adjustable linearly, which allowed enough room for adjustment - with a slightly longer belt; standard is 510 mm - to accommodate a chuck up to 125 mm in diameter. The collets on late models were poor with the smaller sizes - 1.5, 2, 3, 4 and 5 mm - acceptable but the 6 and 8 mm versions with the hole machined eccentrically so the tip of an 8 mm cutter described a 0.7 mm larger radius than the nominal cutter diameter. For some markets the lathe was supplied in a rather good wooden box with a tray holding the accessories - and an additional metal box for the heavier items, the cross-slide, milling bed, etc..
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