email: tony@lathes.co.uk
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South Bend 8-inch Junior
- a photographic essay of a restoration by Dennis Turk -
South Bend Home Page   South Bend 9-inch Junior Photo Essay   
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Offered for sale during 1931, 1932 and 1933 only - although it is possible that some unsold stock might have lingered on into 1934 - the 8-inch Junior was the baby of the Company's range and developed as an even cheaper alternative to the earlier (and much longer lived 9-inch Junior). Everything was done to produce the 8-inch as economically as possible - while also distancing it in desirability from its very much more expensive brothers. Although both the spindle bore (at 3/4") and collet capacity  were the same as the 9" version, the spindle ran in the cast-iron of the headstock, the nose was reduced in size from 11/2" to 13/8" and given a 10 rather than an 8 t.p.i thread. The headstock spindle was fitted with a reducing sleeve to step down the No. 3 Morse taper hole to a No. 2 and the tailstock centre changed from the  usual No. 2 to a rather miserable and limiting No. 1. The spindle drive pulleys were reduced in diameter (limiting the amount of power that could be transmitted) and the compound slide assembly more lightly constructed with a smaller capacity toolpost.
Although Junior models made until 1931 had the beautiful but time-consuming-to-apply (and hence expensive) black "Japanning" finish, this option was henceforth dropped and the lathes finished in ordinary oil-resistant paint of a dark grey slightly tinted with blue. The lathe was listed with various between-centres capacities, from as little as 6
1/2" to 301/2" (South Bend's method was to quote bed lengths, in this case 48, 42, 36, 30 and 24 inches) together with a wide variety of stands and countershaft-drive systems. The latter, also available for the 9-inch Junior, included simple wall and ceiling mounted 3-speed units, neat bolt-on overhead assemblies and a number of under-drive systems built into solidly-constructed stands. The overhead drive on the lathe shown below is the only known to have been fitted to a 8-inch junior (it was a very expensive option) - but others must be out there. Do you have one? The same overhead drive was also offered on the 1934 20-Series 9-inch Toolmakers lathe - yet, oddly was never listed for the much more popular 9-inch Workshop - and was dropped altogether at the end of 1934.
One option exclusive to the 8-inch (and only offered in the dedicated advertising sheets) was to have a single, plain slide instead of the compound unit - and if this was chosen then, in 1932, the cheapest 8" lathe could be whittled down to just $98, and the cheapest 9" $160 - a considerable saving in a time of economic depression and widespread unemployment.
It is almost certain that the 8-inch "Junior" was the first  South Bend lathe to use a remarkably effective system of economical manufacture where the headstock spindle was hardened and subjected to a "super-finishing" technique that allowed it to run directly in the cast iron of the headstock.  Given just a modicum of lubrication this arrangement (also used on many of the later and even more popular 9-inch Workshop models) appear to give the bearings an almost unlimited life. The author has stripped down lathes where years of neglect and abuse had reduced the bed and slideways to scrap, but he has yet to find one where the spindle and bearings were worn to anything like the same extent. Interestingly, not all models were so equipped - for examples of the 8-inch lathe have been found with "babbit" (white-metal ) bearings and in some years the 9-inch Junior was offered in a basic 6-speed form with an unhardened spindle and a top speed of around 630 rpm (the hardened-spindle version had 12 speeds reaching as high as 1250 rpm). Headstocks with bronze bushes have also been found, - though the latter have only been discovered when lathes have been stripped down and were never mentioned in contemporary catalogs.
Other cost-cutting feature of this model were the use of two rather than three V-ways on the bed (a design not returned to until, it is believed, the 1980s when South Bend produced a high-end toolroom lathe with electronic variable speed drive) very basic engineering of the cross and top-slide screw mounts and a simple top-slide feed-screw nut. In place of the usual very neat South Bend screw-in bushings, the cross-feed and top-slide screws were made to run direct in the saddle and top-slide castings (just like a 1910 model) with the screws secured by a pinned sleeve on the inside of each casting. Being particularly difficult to put together - the pinned sleeve had to be secured in place on assembly - this design was only used on the 1931 model with the normal screw-in bushing making a return during the following two years of production. One feature from this lathe was however retained, and used  on all versions of the 9-inch Workshop --the top-slide nut. This was as simple and inexpensive a design as possible, a length of 5/8" round 3/4" long bronze bar held in a cross-drilled hole secured in the bottom casting with a set screw.  The arrangement gave the assembler the chance to raise or lower the nut as needed for alignment - and thus made assembly and fitting of the two castings so much easier.
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South Bend Home Page   South Bend 9-inch Junior Photo Essay   
South Bend Junior Home Page

South Bend 8-inch Junior
- a photographic essay of a restoration by Dennis Turk -
email: tony@lathes.co.uk
Home   Machine Tool Archive   Machine-tools Sale & Wanted
Machine Tool Manuals   Catalogues   Belts   Books  Accessories