Once enjoying the position of producing more machine tools than any other American state, Ohio had, for the first half of the twentieth century, by far the greatest number of large, medium and smaller firms in the trade and produced enormous quantities of all types of metal working equipment. In 1905, for example, it manufactured well over three times as many lathes as its nearest competitor, Massachusetts, and also led in the manufacture of boring and drilling machines, planers, shapers, slotters, threading machines and many smaller specialised items; only in milling machines was it out performed by Rhode Island - a situation that was to be satisfactorily reversed in favour of the Ohioans a few years later.
Typical of the sort of enterprise which flourished in those early years, the Hamilton Machine Tool Company of Hamilton was founded in 1892 by its first president, Mr. Charles F. Hilker, in premises near the junction of Market Street and Monument Avenue. Although the first product was a simple drill press, made in just one size, this proved so popular than, even in the financially insecure year of 1894, Mr. Hilker had generated sufficient confidence in his ability that he was able to raise funds sufficient to erect a new 60 x 200 feet building in Lindenwald - so greatly expanding his production capacity. By 1896 a much fuller range of drills was being sold and, in 1898, Mr. Hilker bought the Belmer Machine Tool Company of Cincinnati and combined their extensive plant with the Hamilton works. Soon the product range expanded to include a wider range of machine tools - radial-arm drills, shapers and planers - with company also becoming increasingly well known for their soundly built engine (centre) and simple capstan lathes of 14, 16, 18, 20, 22, 24, 26, 28, 32 and 36 inch swing. Thus, from humble beginnings, an organisation was created that, at the height of its prosperity in the early part of the 20th century, employed over 3000 people.
Hamilton screwcutting lathes were produced in two versions that the manufacturers designated as "Style A" and "Style B". The A had an early form of screwcutting gearbox, of a most unusual design, built under licence from Edward Flather whose machine tools were well respected in the latter part of the 19th and early part of the 20th centuries - the Style B used ordinary demountable changewheels.
Carrying a patent date of October 15th, 1901 lathes with the new gearbox were quite unlike any other in use at the time However, Hamilton did not recognise the Flather connection in their advertising, preferring instead to call the device the "Universal Screwcutting and Feeding Arrangement". In so far as the drawings indicate, the mechanism consisted of a circular case containing a large ring gear in the form of a short "annulus cylinder" with teeth formed on its inside and outer walls. The inner gear could mesh, one at a time, with eight gears of different sizes arranged around its periphery. The shaft upon which each gear ran protruded through the outside face of the casing allowing the operator to grasp it and so engage and disengage the gears. The outer gear then drove a train of three gears (arranged below and to the side) connected to a reversing bevel box - from where the drive was taken to the leadscrew. Although a very compact design, able to cut 48 different threads from 1 to 56 per inch, contemporary criticism (which was not born out in practice) centred on the fact that, despite being well made from good-quality materials, the reliability and durability of such a mechanism might be questionable. Its complicated method of operation might also, it was claimed, have confused the operator and led to slower work and more mistakes. In the event, the design did not prove a success and the increasingly popular and reliable USA "Norton" quick-change gearbox continued to increase its market share. As a point of interest, the Norton box was not the first of its type, a similar arrangement of gears, of different sizes, placed in a "cone" on a common shaft, having been patented in 1868 by Humphreys. However, the Norton box, helped to class-leading prominence by the Hendey Company who first fitted it to their lathes in 1882, proved to be a long-term success story and it is still used today ijn irs original and modified forms.
If you a Hamilton lathe with the "circular" gearbox, the writer would be very interested to hear from you..