Probably so that it could concentrate its efforts more lucratively elsewhere (as the economy of post-WW2 Californian machine shops started to revive), on August 4, 1949, Small Machines Incorporated was sold/spun off as going business to MasterSon Engineering Co. of 1416 Westwood Boulevard, Los Angeles. In 1953/54 (just three years before their demise) they introduced a line of three new lathes that used the model description "Master". The cheapest in the range was the  Master "Model S" - for "Standard" - with simple bronze spindle bearings; a higher-speed version was also offered, the Master "Model BS" -  for "Ball Bearing Standard" - with a ball-race headstock whilst the top-of the range version was the Master "Model BWW" - for "Ball Bearing Webster-Whitcombe" (Webster Whitcombe being the standard for heavier types of watchmaker's lathe). The BWW had a large-bore spindle with the nose formed to accept standard  8 mm WW type collets; as there was no thread to carry chucks or faceplates these were offered mounted, in the usual way, on collets, the faceplate being equipped with eight drilled and tapped holes instead of slots. Although the models "S" and "BS" were fitted with a set of fixed-ratio fibre changewheels - the last in the train was brass--to provide a power feed to the carriage, the "BWW" was also offered with changewheels for screwcutting - though this is a very rare machine indeed. Also listed amongst the accessories (it shared much of the range offered with the DuoLathe), were the following: a thread-dial indicator, a micrometer-dial equipped tailstock to take WW collets; a push-type WW collet tailstock with stop collar; a tip-up tool rest; 3-jaw self-centering chuck; a 4-jaw chuck (both chucks had hardened jaws); a tailstock drill chuck and centre drill; drill V-pad; a drill chuck adapter for the headstock; a small standard tap and die set by Morris with four taps and four dies (sizes 00-90, 0-80, 1-72, 2-56); one tap and die holder; four bushings and one set-screw wrench. Astonishingly, in 2003, the Morris Company was still in business and selling the same set. Other items included a built-in countershaft unit to give a wider range of spindle speeds, individual WW collets from 0.004" to 0.315" (or sized fractionally from 1/64th to 5/16") and a box to hold 40 collets.
Unfortunately, the Master did not have the backgear arrangement fitted to the DuoLathe and MonoLathe, nor as part of the regular equipment was the variable-speed motor included, but it did retain the graduated cross-feed screw micrometer collar and greatly-improved design of tailstock. Instead of the cross-slide gib strip being a non-adjustable "corrugated" strip of spring steel, the Master was equipped with conventional two pusher screws fitted through the right-hand face of the slide. By this time the accessory case had become metal (neatly made and carrying a small company badge), while also available (and shown at the bottom of the page) was a rather fine, leatherette-covered carry-case with its corners reinforced by steel plates and designed to house the lathe and accessory kit in the base with the top cover secured by toggle clamps.
Fitted as standard with a 110V induction motor (complete with switch a 6-foot cord with plug) an alterative was offered (at $35 extra) in the form of a "universal motor" doubtless based on sewing machine practice, with foot-controlled rheostat control able to be used on 105-120 volts AC, or direct current, that gave a range of infinitely variable speeds from 300 to 3000 r.p.m.
With so few years in production, sales of the Master must have been limited - the last known dated information originating from the Company being marked by the printers '1957' , just  three years after the introduction of a small lathe that was to rightly dominate its market segment for many years - the Emco "Unimat"
If any reader has an example of a Master BWW in their ownership, the writer would be interested to hear from you..

A train of fibre gears lead to a final-drive brass gear attached to the leadscrew, the arrangement proving a usefully slow, fixed-ratio, power feed to the carriage. The motor was supplied without the variable-speed control and fan cooling of the Duolathe.