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Continued:
One interesting version of the Star was the "Universal", designed for light milling duties it came with a threaded spindle nose, to accept No. 2 Morse collets retained by a screw-on nose with a Myford series 7 1.125" x 12 t.p.i. thread., a worm-and-wheel driven fine down-feed and a compound, T-slotted table. It appears that a version of the "Universals" was also sold without the threaded nose for use as a precision co-ordinate drilling machine and these, because there is no method of providing a drawbar to secure the cutter, must not be used for milling - the sideways forces would cause the taper to loosen and the tool to drop out.
The 7-Eight, with its maximum throat of 10 inches and a spindle travel of 5 inches, was fitted as standard with a No. 2 Morse taper socket and was thus designed for the comfortable drilling of holes up to 7'8-inch diameter - that being the largest size drill made with a No. 2 Morse shank. The head used a 5-speed direct belt drive from a rear-mounted 0.75 h.p. 1425 r.p.m 3-phase motor that, in conjunction with an oil-bath reduction gearbox, gave 10 speeds of: 51, 98, 157, 222, 295, 460, 880, 1415, 2000 and 2650 r.p.m. The gearbox was entirely enclosed within the head and used ball-bearing supported shafts carrying gears made from heat-treated steel - a design at variance with some competitors who, for the sake of quiet running, employed rather weaker fibre gears. An oil-level sight-glass was fitted on the left-hand slide of the head. The quill was of substantial proportions and carried a spindle running in a matched pair of angular-contact bearings at the bottom (that absorbed both radial and angular thrust) with a deep-groove ball race at the top. On pillar models the 15-inch by 16-inch (381 mm x 406 mm) table could be swung over under the control of worm-and-wheel gearing and elevated by a rack and pinion. On bench models the head was elevated by a rack-and-pinion gear and the table formed from a heavy casting with three T-slots and a coolant trough around its periphery - this superior unit being available as the rise-and-fall table on the floor-standing pillar version. To simplify changes of speed both front and back sections of the belt guard could be hinged open (leaving the centre section bolted down) and the belt tension quickly slackened and tightened again through a patented (No. 758824) screw-thread-operated scissor mechanism. The spindle return spring tension could be adjusted by hand with its housing marked in the usual way with a scale to indicate the spindle travel. A useful option, though one seldom taken up, was an individually fused and switched built-in low-voltage lighting unit with the bulb neatly mounted inside the underneath of the head.
A heavier version of the 7-eight was also offered, the rare 10-eight that carried a No. 3 Morse taper spindle, a 1.5 h.p. motor and the T-slotted table as standard. In all other respects the machine was identical in capacity and speed to the 7-Eight
The background to O'Brien's was typical of many smaller engineering concerns of the time: the founder, Frederick O'Brien, was first involved in the ceramics trade before going into partnership before World War One with a Mr. Pascoe Tunnicliffe. As the war began the two men turned their attention to the manufacture of munitions but, in 1916, in what appears to have been a sudden split in the arrangement, Frederick bought a disused bakery in Swadlincote and started his own ironmongery and machinery business (still operating today as B.Grice, Ironmongers). By the time the Second World War began, in 1939, Frederick (this time with the aid of three sons), was once more in a position to turn his hand to the making of munitions, a business that naturally thrived and led to his company surviving the conflict with a well-equipped workshop and looking for other work.
Initially, sub-contract machining was undertaken for Qualcast and this rapidly developed into a full-time commitment. However, sensing that reliance on just one source of income was a risky undertaking O'Brien decided to diversify and make two products much in demand to meet the post-war building boom: bench drills and concrete mixers--the latter designed by his brother, Garnet O'Brien..
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