 |
 |
 |
 |
 |
 |
 |
 |
 |
 |
 |
 |
 |
 |
 |
 |
 |
 |
 |
 |
 |
 |
 |
 |
 |
 |
|
|
|
|
|
|
E-Mail Tony@lathes.co.uk Home Machine Tool Archive Machine Tools For Sale & Wanted Machine Tool Manuals Machine Tool Catalogues
Smart & Brown Model M Lathe Model M Mk. 1 Model M Mk. 2 Model A Sabel Model 1024 Smart & Brown Home Page Model L A Model M 'Spare Parts and General Assembly Drawings' book is available
Smart & Brown Model M 4" x 18" This lathe was based closely on the pre-war German Boley L3/L4 with the 6 t.p.i. leadscrew disposed centrally under the bed and the whole of the changewheel bracket arranged to swing in order to provide a "tumble-reverse" to the leadscrew drive. However, the design was not left entirely alone, S & B deciding to fit a conventional full-width backgear assembly instead of the original type that was clustered up against the front spindle bearing - though they did retain the helical-form gears. On the Mk. 2 Smart & Brown further modified the lathe to include a neatly-engineered power shaft along the front of the bed to drive the sliding and surfacing feeds. On some versions of the Mk. 1 (including one owned by the writer) the cabinet stand was in cast aluminium, through most seem to have been in iron. The stand contained a motor, mounted on a simple adjustable plate fitted to slide rails that allowed the easy fitting of alternatives makes and sizes. A typical original fitting would have been a 3-phase, 3/4 h.p. Thomson-Houston 940 r.p.m. unit fitted with a 3-speed flat-belt pulley driving direct to the spindle. This gave nominal speeds of 411, 787 and 1432 r.p.m in open drive and through the 5 : 1 ratio backgear of approximately 82, 157 & 286 r.p.m. Some models are thought to have had a 3-speed gearbox in the cabinet base, in which case the number of speeds totalled 12, through with a very similar span from slowest to fastest. For its size the lathe had a generously large spindle thread - 1 ¾" x 8 t.p.i. backed by a long (1 ¾" ) register length behind. The spindle was machined to take direct-fitting collets with a 25 mm diameter body - though if it were not for this arrangement the bore could easily have been made larger. Interestingly, the collets are almost identical to the Schaublin Type W25 - though the seat in the headstock spindle differs by a couple microns - probably a case of S & B putting the spindle bore on size whereas Schaublin put the collet on size and added 5 microns to the spindle bore. Built in Mk 1 and Mk. 2 versions the first model appeared during late 1946 and the later - considerably modified - in 1948. Production ran, it is believed, until 1959. More details of the lathe's construction can be fond on the Boley page..
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
 |
|
|
|
|
|
|
A just post World War 2 Smart & Brown Model M Mk. 1 on a cast-iron stand and looking very much like the Boley lathe from which it was descended. This model is now very rare.
|
|
|
|
|
|
|
|
|
|
 |
|
|
|
|
|
|
A very early example of the Smart & Brown Model M missing its louvered covers on the face of the stand. The top slide on this lathe has been modified
|
|
|
|
|
|
|
 |
|
|
|
|
|
|
Massive headstock spindle bearings amd expensive helical-form backgears
|
|
|
|
|
|
|
 |
|
|
|
|
|
|
For its size the lathe had a generously large spindle thread - 1 ¾" x 8 t.p.i. backed by a long (1 ¾" ) register length behind. The spindle was machined to take direct-fitting collets with a 25 mm diameter body - though if it were not for this arrangement the bore could easily have been made larger.
|
|
|
|
|
|
|
 |
|
|
|
|
|
|
Hefty bronze housing were used to hold the bed wipers. When new the top slide screw was protected by a sheet-metal cover
|
|
|
|
|
|
|
 |
|
|
|
|
|
|
A thread-dial indicator was built in. Not the adjustable stop for the automatic carriage disengage
|
|
|
|
|
|
|
 |
|
|
|
|
|
|
Boley-like apron controls - though the carriage handwheel is not original
|
|
|
|
|
|
|
 |
|
|
|
|
|
As on the Boley original the whole of the changewheel bracket was arranged to swing in order to provide a "tumble-reverse" to the leadscrew drive
|
|
|
|
|
|
|
 |
|
|
|
|
|
|
|