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      email: tony@lathes.co.uk
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      Berlin Lathe
      - Harald Friedrich & Shne, Traunreut, Obb, Germany -

      Little known outside their native land, Friedrich & Shne & Co. manufactured a range of industrial-class lathes including engine (centre), turret, production, high-speed production - and also a horizontal boring machine. In addition to his interest in lathes, Harald Friedrich also founded the Alzmetall Company, a famous and very successful German maker of pillar and bench drills.
      Developed during the 1950s in co-operation with Dr. Ing.F.Eiselem, a professor at the Munich Technical College who occupied the chair of Machine Tool Research and Technical Instruction, the company's very heavily constructed,  250 mm (9.8") centre height "Berlin" LD-10 and LS-10 lathes were probably their best known export and could be had in either standard form as the Type L with Model Types A,B,C and D) or as the Production Type P that had one additional Model listed, the Type S. The machines were advertised as being assembled on what was called a "Building-up System", a means of providing a customer with exactly the specification required yet still able to be assembled in a factory working to the normal constraints imposed by a regular construction processes.
      Especially deep and rigid, the 400 mm (25.7") wide bed was formed as part of the massive, cast-iron stand cabinet, braced by triangulated ribs between its walls and carried hardened and ground flat and V-ways arranged in a rather unusual way -  those at the front being set below the level of those at the back. The front V-way reflected a fashion of the time where its outer surface (to better absorb wear) was made much wider and set at a shallower angle than the steeper, shorter inner side that took most of the tool thrust. Because the bed ways abutted against the front face of the headstock, and did not run on past them at front and back, the saddle had the cross slide mounted towards its left-hand side to allow the cutting tool to reach the spindle nose.
      Drive and speeds
      Held in the headstock-end of the stand, the drive system consisted of either a separate speed-change gearbox (splash lubricated with hardened and ground gears and shafts) or a mechanical variable-speed unit, using traditional expanding and contracting pulleys - both types being suspended on a self-contained swinging arm by which means the final drive to the headstock, by four V-belts, could be adjusted. Both variable and conventional drives were supplemented by gearing within the headstock, this consisting of hardened and ground shafts and gears running in anti-friction bearings and lubricated by splash. The main spindle, fitted with a No. 5 Morse taper, was bored through a comparatively tight 41 mm (1.6") and ran in adjustable, high-precision double-row cylindrical roller bearings, the one at the front being 90 mm (3.5") in diameter. Although one would have expected the lathe of this size and weight (around 1650 kg or 4620 lbs) to have had its nose formed as a CamLock, American long-nose taper or some form of DIN flange fitting, it was actually a screw thread - a rather inadequate fitting.
      Driven by a 5 h.p. or, to special order, a 7 h.p. motor, spindle speeds varied according to the particular model with the A having a choice of four spindle speeds spanning 67 to 540 r.p.m. 95 to 760 r.p.m. or  130 to 1040 r.p.m.; the Model B with eight speeds of 33 to 380 r.p.m., 47 to 540 r.p.m. 67 to 760 r.p.m. or 95 to 1040 r.p.m.; the Model C with a choice of twelve speeds, either 30 to 380 r.p.m. 42 to 540 r.p.m., 56 to 760 r.p.m. or 84 to 1040 r.p.m. and the Model C was fitted with an infinitely variable-speed drive system that could give, to a customer's preference, either 16 to 920 r.p.m. or 23 to 1300 r.p.m.--the rate being controlled by a long lever emerging from a boss at the bottom of the headstock-end plinth
      Electrical control of the spindle - stop, start, reverse and braking by a counter-current system - was by a third-rod system with two operating levers, one pivoting from the right-hand face of the apron and the mounted just outboard of the screwcutting and feeds gearbox. On the variable-speed model, to inform the operator of how fast the spindle was turning, a neatly cowled rev counter was fitted on top of the headstock.
      Continued below:

      Friedrich & Shne "Berlin" Type LD-10 lathe fitted with infinitely variable-speed drive

      Screwcutting and feeds
      Lubricated by a pressure pump and fitted with a double reversing gear that allowed the drive to leadscrew and powershaft to be engaged, disengaged or reversed, the screwcutting and feeds' gearbox was controlled by a conventional tumbler selector and five dials. Without altering the changewheel drive, the box could generate 32 metric and 32 English pitches as the Models A and Model B and 80 of each, plus 40 Module threads, as the Models C and Model D. Longitudinal power feeds on the A and B machines totalled 28, ranging from 0.1 to 0.6 mm (0.004" to 0.024") per revolution of the spindle (with power cross feed set at half those rates), and 90 rates on the C and D ranging from 0.04 to 2.4 mm (0.0015" to 0.094") per rev. Most usefully, the lathe was fitted with a mechanism whereby both longitudinal and cross feeds could be automatically disengaged at a number of pre-set points. Various alterative sets of changewheels were available to cut other pitches, the gears being tempered and running on hardened and ground splined shafts carried in anti-friction bearings.
      Able to traverse a distance of 980 mm (38.5") along the bed, the carriage was heavily built and fitted with a double-wall apron holding hardened and ground gears with an oil sump in the base from which lubricant was taken by a automatic mechanical pump together with a hand plunger to the internal parts and also the bed and cross slide ways.
      Following modern practice, the saddle wings were not equipped with T-slots, but  the edges of the cross slide ways were, these extending across the full width of the saddle to permit the fitting of a travelling steady or adjustable stops. Two very unusual options listed were the fitting of a "
      double saddle with through-passing bottom slide" or one described as a "double saddle with separate bottom slides" - though how these were arranged is not known.
      With 305 mm (12") of travel, the cross slide carried a top slide able to be rotated through 90?each side of central and able to be fitted, as an option, with  power-feed, a quick-withdrawl lever for use when screwcutting and either 4-way or quick-change toolposts. The micrometer dials were of a usefully large diameter and finished in a non-glate satin-chrome finish - the grauations being at intervals of  0.05 mm on metric models and 0.002" when English.
      Able to be set over for the turning of slight taper, the tailstock had a spindle with a travel of 130 mm (5.125") and a No.4 Morsev taper socket. Unfortunately it was locked to the bed not by a captive lever, but a loose, self-hiding spanner.
      Accessories of the usual type were offered, including: 3 and 4-jaw chucks, faceplates of conventional cast-iron or cast-steel construction, fixed and travelling steadies, 4-way and quick-set toolposts (with one by Multifix), a Kienzle speed selector, coolant equipment, taper turning, hydraulic copying and lighting.
      One wonders how many Berlin lathes have survived; if any reader has one, or details of the Company's other machine tools, the writer would be interested to hear from you.

      Varaible-speed drive of the Berlin LD.10

      Carriage - the top slide is fitted with the simplest possible form of toolpost

      Inside the headstock. Note  for such a large lathe, the comparatively slender proportions of the main spindle and its hearing

      Internals of the screwcutting and feeds' gearbox

      Facia of the screwcutting and feeds' gearbox with tumbler and dial controls

      email: tony@lathes.co.uk
      Home   Machine Tool Archive   Machine-tools Sale & Wanted
      Machine Tool Manuals   Catalogues   Belts   Books  Accessories

      Berlin Lathe
      - Harald Friedrich & Shne, Traunreut, Obb, Germany -