On August 4, 1949 Small Machines Incorporated (doubtless suffering a financial crisis) was replaced by a new company incorporated as 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 lathe 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 Large Spindle". This latter machine had a large-bore spindle with the nose formed to accept standard  8mm WW type collets. Although the models "S" and "BS" were fitted with a set of fixed-ratio fibre changewheels (though the last in the train was brass) to provide a power feed to the carriage the "BWW" was offered with changewheels for screwcutting - though it must be admitted non so equipped have ever come to light. Also listed amongst the accessories was a thread-dial indicator, a built-on countershaft unit to give a selection of spindle speeds and various "factory-installed accessories" - a remarkable achievement in a lathe only 10 inches long, though unfortunately non of these extras ever appear to have been illustrated in the (very sparse) company's advertising literature.
Unfortunately the Master range did not have the backgear arrangement of the Duo lathe, nor the variable-speed motor, 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 range was equipped with two adjustment screws fitted through the right-hand face of the slide.
With so few years in production only limited numbers of these lathes can have been made and, if any reader has an example in their ownership, the writer would be interested to hear from them.