Made in small numbers during the early 1950s by A. Nothelfer & Söhne, at Ravensburg in southern Germany, the Nora was an unusual - and now very rare - miniature precision milling and co-ordinate drilling machine. Patented under the number 813923, applied for in July 1949 and granted in September 1951, it employed a combination of features seen in three other interesting designs: the Ames "Triplex", Arboga UM400 and Aciera F1. Both Arboga and Aciera attempted, like the Nora, to combine maximum versatility with great accuracy and, whilst the Aciera undoubtedly achieved this (in combination with a wide range of accessories) its selling price was astronomically high. Taking a simpler, more affordable approach, the Nora mounted its head and motor (with drive by a narrow V-belt) on a sickle-shaped arm that allowed it to be moved from horizontal to vertical--and also locked in any intermediate position. Prismatic in section (allowing a powerful lock to be obtained) the arm was fitted with a 90-degree scale with the head-mounted pointer engraved with a vernier sacle Developing 200W and running at 2300 r.p.m., the rather long 3-phase motor fitted as standard gave just three spindle speeds - 700, 1400 and 2800 r.p.m. - where four (or six, by using a 2-speed motor) would have been more useful. Although the use of a curved arm would necessarily have imposed a limitation on overall rigidity, as the machine was intended only for light work, this would not have been a practical drawback.
Build in at least two versions, the Nora was available as a Mk. 1 and a Mk. 2 - the latter a thorough and complete revision of the original. Not only was every casting increased in mass, but the arrangement of the vertical feed re-engineered and the slots that allowed the head casting to be closed down to lock the spindle rearranged. Unfortunately, although the Mk. 1 was fitted with both screw and quick-action rack feed to each horizontal movement of the 3.250" x 8.625" table (and so ideally equipping it for slotting work), on the Mk. 2 this facility was dropped and only screw-driven feeds fitted. On the Mk. 2 the main column and knee were both considerably heavier and the latter triangulated to add even greater stiffness. The saddle and table were given larger, cast-in and stepped-out feed-screw support brackets, the arrangement allowing a little extra useful travel as the end of the (3.375" x 8.625") table was able to pass inwards over the right-hand face of the saddle. In addition, on the example shown below in the photographs, it has allowed the fitting of feed screws and large-diameter micrometer dials from a Schaublin 102 lathe. To ensure that the slides could be adjusted to move with the minimum of play (5.55 inches longitudinally and 3.375" across) each carried a row of very closely-spaced gib-strip adjustment screws - a feature all to rarely adopted by other makers. The 4 inches of vertical feed on the Mk. 1 was very simple: rack-and-pinion gearing was used to lift the knee, an adjustment made to a micrometer-dial stop and the table let down to rest against it. On the Mk. 2 the mechanism was altered to a ratchet feed - though with a cleverly arranged facility that allowed a very fine adjustment to the setting by the use of a large diameter micrometer dial attached to a knurled-edge ring that turned a short screw surrounding the elevation post.
Able to be slid in and out of its casting under the control of a long lever, the 0.42-inch bore spindle ( 0.396" on the Mk. 1) was originally formed with a 20?taper in its nose to accept the maker's own design of 12 mm shank collets that were supplied in a set from 1 to 10 mm. On the machine illustrated, it was a simple matter to have the nose reground to accept the common Schaublin W12 type with a 15?angle.
If you have a Nora, the writer would be very interested to make contact.
My thanks to Dr. David Samways of Anglo-Swiss Tools for some of the photographs and valuable background information..