E-MAIL   Tony@lathes.co.uk   
Home    Machine Tool Archive   Lathes, Millers Shapers & Grinders for Sale
Machine Tool Manuals   Machine Tool Catalogues


ETA Lathes
Maker's Care and Screwcutting Charts   ETA Rebuild Photographs  ETA Original

"ETA" (the Greek symbol used by physicists for "efficiency") were a Leicester firm, with their factory originally located at 70A Asylum Street and then in Weford Place, right in the city centre, and under the control (before World War Two) of a Mr. Harry Wildbore. The lathes were accurately built - the National Physical Laboratory used them - and made from good-quality materials to a decent specification. Although built in limited numbers a surprising number have survived in remarkably original condition, testament to the quality of their construction and (of course) efficiency in operation. Although the first examples are known to have been manufactured in 1912 it was not until after the First World War that production started in earnest. Unfortunately, the very early machines have no identifying marks but, should you be lucky enough to come across one, their distinguishing features make them relatively easy to recognise. Later lathes had the name "ETA" cast into the bed and, later still, the words: The ETA Tool Co. Leicester, England.
As its name implied the "Economic" was a simplified version of a more expensive and better-equipped machine, the Model X. This latter machine was entirely conventional, with a stress-free cantilever bed, finely-adjustable bronze headstock bearings in tapered seats, proper clasp nuts on the (0.75") 8 t.p.i. square-thread leadscrew, a geared-down drive between carriage handwheel and bed-mounted rack, engraved micrometer dials, a twin-arm banjo quadrant to carry the changewheels (allowing the easy mounting of compound gear trains), a proper compression clamp on the tailstock barrel and, on some models, both light (and easily-lost) backgear guards and a fine-feed to the saddle driven by belt from an extension to the tumble-reverse output gear. The "Economic" could be bought with or without a 9 : 1 ratio backgear; however, in the latter case, it was still possible to retrofit it, the mechanism being bolted to separate brackets at the rear of the headstock and offered by the makers in their accessories catalogue.
Strongly made the 8.5" x 4.5" cross slide was fitted with three large T-slots - into any one of which the top slide, with its graduated swivelling base, could be located. Although the carriage assembly was of substantial proportions, it was still able to be operated when the headstock and tailstock centres were brought together - and hence possible to turn very short workpieces between centres. In the early 1930s, facing increasing competition from other makers of cheaper lathes, a small milling machine, a drill and a tool and cutter grinder were added to the company's product line.
One lathe remains a mystery as to its type number - a model with an overhung powershaft, driven from the headstock end of the leadscrew, designed to provide a sliding feed along the bed without wearing out the clasp nuts. An illustration is at the bottom of this page.
In 1934 the design rights were acquired by the Leicester machine-tool makers J.W.Bamkin, but no further examples of the lathe were made - the reported loss of the patterns in an outside foundry fire could not have helped. Bamkins, however, continued to produce the ETA miller for a few years whilst the tool and cutter grinder remained in production, it is reported, until the 1970s, even after the Company moved further out of Leicester to Barkby Road during the 1960s when the manager was Alf Riley..
Only one ETA passed through the writer's hands in recent years; this was removed, complete with its original motor, from the shed in Leicester were it had been installed in 1933. It was in remarkably fine, original condition and turned out, on close inspection, to be a particularly well-made and finished little lathe whose strength and rigidity were significantly better than the contemporary Drummond model. It was restored by its new owner - and the first pictures can be seen here.

ETA "Economic" 41/8" x 16" backgeared screwcutting lathe of the 1930s with flat-belt drive

Saddle to bed fitting - showing the vertical shear on the inside thrust face. The tailstock and apron were located on different bed shears so that wear on one would not affect the location of the other.

Headstock spindle (with the drive pulley removed) showing an adjustable cone bearing at the front (in cast-iron on some models), and a Duplex combined radial and thrust ball bearing at the rear. Other models had adjustable cone bearings at each end and a ball thrust race to the left-hand end of the drive pulley. The conical bearing was made to slide in its housing by the means of nuts at each end, which gave a wide range of adjustment to compensate for wear. The spindle bore was 3/8", the nose thread 11/8" x 10 t.p.i and, according to the maker's literature, the centre a No. 1 Morse taper - however, examples have also been found with a 2 Morse fitting.

Section through tailstock and bed fitting.
The tailstock was automatically pulled up to a vertical face on the back shear of the bed - whilst being simultaneously being clamped to the top surface.
Interestingly, ETA did not consider a "set-over" tailstock worth the trouble of misalignment and  offered instead a sliding "false centre".

Judging by pulleys designed to take a light round-leather "gut" drive this Model X ETA was probably made before 1925.

The Model X was conventional but well-made with a stress-free cantilever bed, finely-adjustable headstock bearings in tapered seats, proper clasp nuts on the leadscrew, a geared-down drive between carriage handwheel and bed-mounted rack, engraved micrometer dials and a proper compression clamp on the tailstock barrel.

Heavily-built backgears and, for a small lathe, a robust headstock casting

The tumble reverse leaver had to be unbolted before its position could be altered. For compounding the gears were held together with simple pins
Note the Drummond-like round changewheel retention nuts.

Neatly matched headstock and bed casting betray better-then average attention to detail

Unlike some ETA models with bolt-on backgear brackets this version has them formed as part of the headstock casting

The changewheel banjo was provided with a handy quick-release lever

Although relatively light the apron carried split nuts to grasp the leadscrew, a geared-down drive to the (pleasant-to-grip "balanced") carriage traverse handwheel.

The chain link between flywheel drive and treadle is missing - but used as part of the mechansim a modified lathe drive dog. Unlike similar contemporary lathes that used plain bearings ETA engineered a proper housing to hold free-running ball races.

A very rare ETA with an overhung  powershaft to provide a sliding feed without using (and wearing out) the leadscrew

E-MAIL   Tony@lathes.co.uk   
Home    Machine Tool Archive   Lathes, Millers Shapers & Grinders for Sale
Machine Tool Manuals   Machine Tool Catalogues


ETA Lathes
Maker's Care and Screwcutting Charts   ETA Rebuild Photographs  ETA Original