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Distinctly different to the 00 Series, the larger 01 and 02 Elliott Omnimil were much more massively built and with a dovetail ram that could be swung front to back to present either a 4-speed vertical head or a pair of horizontal arbor supports; the two models were very similar but the 02 was intended as a heavier-duty type with a five-inch longer table (with an extra five inches of longitudinal travel and one-inch in traverse), a modified knee with a power rise and fall and a 5 hp instead of a 4 hp motor to drive the horizontal spindle - although this change did not alter the speed range.
As with many Elliott millers, the 01 and 02 were not unique models but shared all their major components below the head with other machines in the range, in this case mainly the long-running and popular U1 and U2 horizontal models. By combining the functions of a swing, tilt and slide high-speed vertical turret head with accessories mounted on the horizontal arbor (and table) the makers claimed that the miller was a combination of eight machines in one and able to perform vertical and horizontal milling, drilling, jig boring, die-sinking, rack milling slotting and shaping to a standard equal to that of stand-alone machines.
Like most larger millers the 01/02 was built around a substantial column casting that was bolted and dowelled to a heavy foot that doubled as a coolant tank whilst supporting an externally mounted coolant pump; the inside of the foot was ribbed to increase its rigidity and advantage was taken of the partitions so formed by using them as swarf settling traps. A door on the left-hand side of the column gave access to the electrical system and a swing open cover at the rear exposed the motor and its double-stepped (2-speed) pulley. From the motor a pair of V belts took the drive up to a 6-speed gearbox (built into the body of the column) that gave, in combination with the belt drive, a total of 12 speeds from 31 to 1010 rpm. The gears in the main drive were all manufactured from hardened nickel-chrome steel with their teeth rounded off on the ends, but only those considered by the makers to be of the faster-running kind were ground finished on their teeth. All the gearbox shafts ran in ball or roller bearings and had their splines ground in; the gears were of substantial size (the largest nearly 10 inches in diameter) and, to help the operator engage them, the electrical control system was fitted with an inching button to bring the teeth into line. To aid reliability the oil in the sump beneath the gears was distributed under pressure by a mechanical pump.
The 40 INT nose horizontal spindle was made from hardened and ground nickel-chrome steel forging and ran in two precision taper roller bearings at the front and a single roller bearing at the rear. The tool-carrying 1-inch (or 27 mm) diameter arbour was also a precision ground forging of nickel-chrome steel and carried a set of lapped spacers; it was supported in two drop arms, the outer fitted with an adjustable bushing. The overarm was of the dovetail type and was cored from one end only to provide an unbroken and hence twist-resistant tubular section; its slides were precision ground to fit into the hand-scraped slides on top of the column turret. An overarm clamping brace that coupled to the knee was supplied as standard.
The knee was fitted with a "one-shot" lubrication plunger that supplied oil to the table gearing, the table feed screw and both the table and knee shears. The table on both machines was ground finished on the top surface and had T-slots cut from the solid, not cast-in, and was driven by a carbon-steel screw running through two adjustable bronze nuts. The table carried a handwheel on its right-hand end only with the other side reserved for the mounting of a drive to run either a standard "universal" or a special rack-dividing attachment. Both millers shared a "universal" saddle that could be swung 45° in either direction but the tables were different sizes: 40" x 11.375" on the 01 and 45 x 11.375" on the 02; the latter also had power feed fitted to the knee rise and fall.
Power for the feeds was taken not from individual electric motors but from a subsidiary of the column spindle gearbox - hence the 18 power feeds, although very useful in number and rate, had the disadvantage of being tied into and changed with the selected spindle speed. The feeds engagement was through case-hardened dog clutches and each axis of feed was fitted with an adjustable, automatic trip.
With swing saddles and power feeds in all directions (and a "rapids" version built later) the assembly of parts within the knee was necessarily complex - and disassembly not for the faint hearted.
Modelled on the successful Bridgeport pattern, the "Omnimill" vertical turret head had its the 1.5 hp drive motor integrated into the front section of the arm but, happily, set back and driving forward by a V belt (through 4-step pulleys), this arrangement meaning that there was no obstruction to the spindle being fitted with a proper through draw bar. Both the ram's sliding feed and the head's angular moment were under the control of capstan-like handwheels and, besides a brake assembly, the head was also provided with a lathe-like backgear arrangement that doubled the number of speed to 8 and gave a range from 80 to 2700 rpm. The hardened and ground 30 INT taper spindle ran in precision double row angular contact bearings with its drive pulley mounted on its own bearings to mitigate the effects of belt pull. A quick-action drill feed was fitted together with a worm-and-wheel type fine-feed hand drive and three rates of power up and down feed: 0.0015", 0.003" and 0.006" (0.04 mm, 0.075 mm and 0.15 mm); an automatic trip was provided in both directions.
A range of accessories was available including an Elliott-manufactured 10-inch dividing head of the ordinary "universal" type or a special rack-indexing unit; a universal milling attachment (without quill feed), a slotting attachment and a combined slotting and punch shaping attachment - all three of which mounted on the horizontal spindle socket. Also listed were all-steel and semi-steel plain and swivelling-base machine vices, a special self-centring bar vice; two sizes of Elliott brand collet-type cutters holders, a boring head, open and closed tool cabinets, optical measuring equipment, cutter guards, low-voltage lighting and various sizes of rotary table..
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