Manufactured by the American Hardinge precision lathe and collet company the first Cataract horizontal and vertical millers, constructed before World War 1, were small machines standing just 161/2" high. They made use of several already-existing parts - the main body casting was topped with a replica of the precision bench-lathe bed, to which a slightly modified No. 3 lathe headstock was bolted, whilst the knee and compound table were identical to those offered as conversion kits to turn the company's lathes into horizontal millers. As a further economy the table power-feed arrangement was provided by the same drive used on the lathes as a screwcutting attachment - and also retained the very useful adjustable automatic knock off control. There was no overarm support for the cutter and the machine would have been limited to work of a lighter duty only.
The table had a maximum clearance of 61/2" from the spindle and was 12" long by 33/16" wide; it carried one central T slot, which had bevelled sides to locate fittings such as the dividing unit, and two plain outer T slots for clamping work. The table had a cross travel of 4" and could be moved longitudinally through 51/2" by a screw feed or by 5" using a rack-operated lever mechanism that bolted to the same location used for the power-feed attachment. Before the lever feed could be engaged the main slide nut had to be removed but, as this was exposed on the side of the knee casting, the job took only a moment to accomplish. The micrometer dials were all of the indexing type, 17/16" in diameter and graduated to read in thousandths of an inch.
The knee and compound table of the vertical miller was identical to that used for the horizontal and, whilst the head casting was completely different, it used the same spindle and bearings found in the Cataract No. 3 lathe headstock.
Another much larger and stronger miller, the No. 5, was also produced from around 1912 and continued to be manufactured, in a modified form with an enclosed drive, into the 1930s.
Improved Cataract millers, first produced during the 1930s, followed to some extent the development of the company's bench lathes having completely enclosed V-belt drive systems with the two-speed motors operated by neat external levers. Later still Hardinge dropped the Cataract label and advertised the machines, with further modifications and additions to the range, under their own name. All Hardinge Cataract millers were available with a range of high-quality accessories; some are shown on this page and others here.