The Norwegian Metal Gasket Factory Lathe
Obviously inspired by the South Bend 9-inch "Workshop" lathe (as first manufactured in the early 1930s), this Norwegian-built example was, it is reported, one of a batch of 30 constructed during 1940. Responsible for its production was the Norwegian Metal Gasket Factory, a concern whose main business at the time was the manufacture of metal gaskets for steam engines, the necessary bronze and metal parts being cast and machined in-house. In 1939 the company name was changed to The Norwegian Metal Gasket Factory and Vestlandske Art and Metallst°peri. In 1994 operations were partitioned off into a separate company, Nomek Maskinvereksted AS, who continue to this day.
Using a V and flat-way bed, carriage assembly and tailstock reminiscent of the American South Bend 9-inch, the Den Norske had a 130 mm (5.125") centre height and took 580 mm (22.75") between centres. Bored through a useful 26 mm (the South bend was only 19 mm), the spindle ran in parallel bore bronze bearings (50 mm at the front, 36 mm at the left) that were drawn by ring nuts into tapered sockets - the effect being to close them down and so adjust the running clearance. End thrust was amply catered for being taken by two ball races, one on the inside of the left-hand headstock wall, the other on the outer. Mounted centrally on the saddle, the cross slide appears to have a had a gib strip of the tapered type with a rather small micrometer dial and a traditional "balanced" handle. Long swarf guards were fitted to the saddle's left-hand wings, these being arranged to pass in front of and behind the headstock as the carriage approached the chuck
A heavily constructed countershaft was provided with an over-centre tensioning lever the setting of which was adjusted by the usual left-and-right-hand-threaded nut. Driven by a factory-fitted 1 h.p. 1400 r.p.m. motor, eight spindle speeds were provided: four by direct drive using an "A" section V-belt running over 4-step pulleys and four in backgear. In addition (though how this was provided is not clear) a single extra speed of 1000 r.p.m was also listed as being available.
Fitted with a No. 2 Morse taper spindle, the tailstock could be set over for the turning of slight tapers - though money was saved by omitting a cam-action cross shaft and using instead a simple eye-bolt locked by a self-hiding spanner.
Should any reader have a Den Norske lathe, or other machine tool, the writer would be interested to hear from you.
The success of the original South Bend 9-inch, and its suitability as a general-purpose workshop lathe, can gauged from the number of copies produced - more than twenty-two - including: English ones by Smart & Brown, Boxford and Ace; the Australian Hercus, Sheraton, Purcell and Parkanson (the latter the brand name of Theo. Park & Son, Engineers ,Melbourne); the Swedish Storebro, Blomqvist and Asbrinks; the Brazillian-made Sanches Blanes, Joinville and Boffelli & Finazzi, the French UFP, the Taiwanese "Select" in various versions, the Moody from Canada, and from Argentine the S.R.L. San Francisco (CBA), Industria Argentina. Another copies were the mysterious NSTC (probably American, but about which nothing is known) and the Brtish "Unitol", a name more often found on the Heavy-10 South Bend but perhaps (like the Heavy-10), this was a real South Bend just rebranded with the Unitol name cast into the iron cover that guarded the belt running from motor to countershaft..