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American machine-tool makers, based in Cincinnati, Ohio, the Champion Tool Works appear to have concentrated on conventionally designed but strongly-built centre (engine) lathes of between 12" and 18" swing. By 1900 Cincinnati had grown to become the leading machine-tool centre in the United States with over thirty firms - and the State of Ohio as a whole accounted for some 30% of US production of metal-cutting machinery.
Champion lathes of each size - they made machines of 10, 12, 13, 14, 16 and 18 inches capacity in the early part of the 20th century - were individually specified and did not share any of their bed or carriage components with either larger or smaller machines from the range. All models appeared to have straight (no gap) internally-ribbed V-beds with two Vs at the back, one at the front and a single flat; the headstock and tailstock shared the same V and flat - the carriage running on the other pair. The rack, in steel, was bolted and doweled to the side of the bed rather than through the top and was engaged by a handwheel which could be moved into and out of mesh as required.
All headstocks - from smallest to largest - held a spindle manufactured from hammered "crucible" steel (made in small quantities in individual clay pots) and ground on all surfaces and running in phosphor-bronze 'boxes'. The 12-inch and 14-inch lathes all used a standard type of backgear, unlocked from the spindle by a simple spring-loaded plunger, with reduction ratios of 8 : 1 and 9.1875 : 1 respectively. The 16-inch lathe was fitted with a special Double-ratio Backgear with reductions of 10.5 : 1 and 3.3 : 1 - either of which could be selected without stopping the lathe, or the operator having to move away from his normal working position at the front of the machine.
Whilst the single-wall apron on the 10" and 12" lathes mounted a positive mechanical linkage to engage the power sliding and surfacing feeds, on the larger lathes, with deeper and stronger double-walled aprons, friction clutches, controlled by rotary handwheels, were used instead. On all models the direction of the feeds could be reversed from both the apron and the headstock - a great convenience when the operator was chasing piece-rate pay - and an automatic disengagement mechanism, which worked in both directions, was fitted to the sliding feed.
Engaged through a tumble-reverse gear on the headstock the leadscrew carried a long slot by which means the power feeds were taken up by the apron. Screwcutting on all models was either by a full screwcutting gearbox or by a three-speed box which gave three sliding and surfacing rates for each setting of the changewheels. The screwcutting gearbox could be specified to generate either English or metric threads and all lathes so equipped had a choice of 40 different threads and rates of feed without altering or changing anything on the gear-drive system.
Of a good length, the saddle carried the compound slide rest on its centre line - a design feature that, as it required the bed ways to extend some way in front of and behind the headstock, gave excellent support to the cutting tool when working in close proximity to the chuck.
The tailstocks of the 12-inch and 14-inch lathes had daylight showing between the front and rear barrel-housing supports but larger versions were more heavily built, with a "solid" casting. The 12-inch lathe had a tailstock barrel 19/16" in diameter with a No. 3 Morse taper - all the larger lathes had a 115/16" diameter barrel - but retained the same size of Morse centre.
All pinions and studs in the lathes were hardened and ground and gears smaller than 3 inches in diameter were in steel rather than cast iron. Screws subject to wear when covers were removed for cleaning and servicing were hardened
Supplied with each lathe was a double-friction countershaft with a shifter hook and eye, large and small faceplates, a set of screwcutting changewheels (or a screwcutting gearbox if specified), fixed and travelling steadies, centres and the necessary wrenches.
A wide range of extras was available - including changes of specification which included a double backgear assembly - oil pans, taper turning units, self-indexing bed-mounted turrets and collets, etc..
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