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.
An interesting addition by the maker (at least on some versions, if not all) was to provide the outer end of the headstock spindle with a No. 2 Morse taper socket and an external thread. In addition, a No. 2 Morse taper mandrel was included with a nut and washer that allowed a grinding wheel to be attached - handy when a tool needs sharpening or to possibly configure some arrangement without having to unclamp a job held in the normal position in a chuck, collet or between centres.
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 toolkit, 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 - giving a capacity between centres of, respectively, 250 and 400 mm. It is now known that these two versions were, in effect, different models, the longer-bed type having a No. 2 Morse taper tailstock instead of a No. 1 and its motor reversing switch on the right-hand side of the lathe rather than the left. However, other basic constructional details remained common to both--a bed width of 410 mm, an overall height of 285 mm; when stripped, the basic short-bed machine weighs just 60 Kg with the accessory kit adding 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 a large number of standard accessories.
An example of the longer-bed lathe has labels stating:
мичуринский приборостроительный завод прогресс
токарный настоловый станок
модель ТН-1 но. 2321
...this translating as:
Michurinsky Instrument-Making Plant progress lathe table-top machine model TN-1 number 2321
Over time, it seems that several variations on the basic machine were 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 toolkit
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) - that allowed a chuck up to 125 mm in diameter to be mounted. 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 export markets, the lathe was supplied in a rather well-made wooden box with a tray holding the accessories and an additional metal box for the heavier items such as the slide-rest assembly and milling slide..