By Dan Eyring

All the information in this article comes from the following website: http://www.lathes.co.uk/stark/


Founded in 1862 at 222 Moody Street, Waltham, New England, U.S.A., the Stark Tool Company is an important name in the history of American close-tolerance engineering - and one that survived into the 1950s when they were still making a well-developed version of their original machines.

 

Stark No. 4 Lathe on the maker's superb iron-framed oak cabinet stand with self-contained drive system.

 

A stark with its headstock pulley arranged in reverse of that normally found and with an unusual mounting on the flat end of the lathe bed, a small compound table set up for use as a horizontal milling machine complete with a swivel dividing head and tailstock - and with the cutter carried on an extension of the headstock spindle; the bevel-gear operated knee elevation was a particularly compact and well-executed design. The original version of this attachment can be seen here.

A typical Stark lathe, a No. 4 Precision Bench with a 38" long bed with 20" between centers and a swing of 9".  The collet capacity of the later No. 4 lathes was increased from 0.75 " to a full 1". Note the T-slot machined into the right-hand face of the cross slide.

The Stark Tool  Company was almost certainly the originator of the Precision Bench Lathe - as eventually made by a variety of firms in the U.S.A. including: Derbyshire, Levin, Bottum, American Watch Tool Company, B.C.Ames, Hjorth, Potter, Pratt & Whitney, Rivett, Wade, Waltham Machine Works, Wade,  Pratt & Whitney, Rivett, Cataract, Hardinge, Elgin,, Remington, Sloan & Chace, Crystal Lakes, Ballou & Whitcombe, Crystal Lake, Frederick Pearce, Sawyer Watch Tool Co., Engineering Appliances Co. and Fenn-Sadler. They were widely copied in Europe and developed as, amongst others, the Schaublin, Lorch, G.Boley, Wolf Jahn, Carstens, Mikron and Simonet.

Stark's claim as originators of the type was bold and unequivocal (and printed on all their sales catalogs), with the first examples being built by John Stark personally in 1862, well before any of his competitors - who were also mostly from the Waltham area. The company was also famous for their watchmaker's lathes and also built a wide range of specialised machinery and tools for use in watch and clock-manufacturing and repair plants.

Eventually to be made in six models - based around four different beds and headstocks - the Stark precision bench lathes were available with swings varying from 5.875 " to 12" and collet capacities from 0.25" to 1.25". Incredibly, production continued well into the 1950s, with small advertisements for their Series 400 and variable-speed underdrive No. 4 and 41/2 and bench-mount No. 3 precision plain-turning lathes appearing in the machine-tool trade press. Although Stark have now disappeared the American tradition of very high quality precision plain-turning lathes is continued into the 21st century by both the Derbyshire and Levin companies.

The basis of all early models was a bed with beveled edges and a single central T slot that located the headstock, tailstock and fittings such as a compound slide rest or hand T-rest. However, at the heart of the lathe's accuracy was a superbly-made, high-speed headstock spindle and bearing assembly based on a design already standardized for watch lathes where a hardened, ground and lapped spindle ran in glass-hard steel bearings - a system which represented the very best use of the materials and manufacturing techniques available in the late 1800s. The spindle and bearings were originally advertised as being manufactured from "English steel" - almost certainly a reference to crucible steel, the contemporary (Huntsman) method of producing small quantities of high-quality metal with tightly-controlled properties. The headstock design continued unchanged until the late 1920s when the option of precision ball bearing spindles was offered, at first to special order - and then only recommended by the makers for applications where very high speeds had to be sustained for long periods.