Of an entirely different design and intended for heavier duty use than the 180-DN and 200-DN models, the Eriksen 180-NE and 200-NE lathes were both of identical mechanical specification save for their centre heights, that for the former being 7 inches and the latter 8 inches. Each model was available with a choice of three bed lengths - that gave 40, 60 and 78 inches between centres - all being fitted with a detachable gap piece that, when removed, allowed a workpiece 223/4" in diameter on the 180-NE and 243/8" on the 200-DN to be turned on the faceplate - the depth of the job limited, in each case, to 63/4 ". High-resolution pictures - may be slow to open
Made from an alloyed cast iron, the 113/4" wide, box-section bed had its front and back walls braced by diagonal ribs and used V and flat ways - though these were not hardened, nor was this process offered as an extra. To better absorb wear, the front V had its outer surface made wider and set at a shallow angle to better absorb wear while the inner section was shorter and steeper to take tool thrust. Although as standard the lathe was supported on two separate cast-iron, box-type plinths joined by a sheet-metal chip and coolant tray, as an extra-cost option, a heavy, full-depth cast-iron cabinet could be supplied, this having a small compartment at each end, the one under the headstock containing the electrical control gear with its door secured against opening unless the main switch was in the off position.
Fitted with hardened and ground gears, the headstock had 18 speeds arranged in geometrical progression at a ratio of 1.25. Two ranges were available, the standard 22 to 1120 r.p.m. or a special version (that incorporated some other modifications) of 45 to 2300 r.p.m. Both were driven by the same 5 h.p., 1400 r.p.m. 50 Hz motor that could be either flange mounted against the headstock's left-hand face, or at the back with drive to the input pulley by three V-belts. Electrical stop, start and reverse were controlled by a "third-rod" system, the operating lever pivoting from the apron's right-hand face (and so moving with the carriage) - the system incorporating an adjustable, multi-plate clutch and combined brake unit with a built-in shock absorber. When operated, this mechanism braked the spindle to a stop but left the motor running but the spindle stopped.
Bored through to clear 2 inches, the hardened and ground headstock spindle carried a sleeve-down-adapter to take a No. 3 Morse taper centre and (unusually for a lathe made at this time) a threaded nose instead of American long-taper safety fitting. The specification of the thread is not known - and may have been to a customer's particular requirement. The spindle was supported at the front in a special, high-precision bearing with four rows of caged balls while the headstock with the high-speed option - 45 to 2300 r.p.m. - had the bearing fed with a pressurised oil supply taken from a circular manifold in the roof of the headstock that also directed oil, through a series of pipes, to various points within the housing. At the rear, the spindle ran in another high-precision bearing, a twin-groove type. Final drive to the spindle inside the headstock was by a single gear of helical, form, all the sliding gears - and the clutch/brake - being arranged on layshafts to the rear.
Coolant equipment was optional and, when fitted could only be switched on when the main motor was running, two red lights indicating that power was going to both main motor and coolant circuits. A single push button was provided as an emergency stop to cut the power to both.
Screwcutting was by a Norton-type quick-change gearbox with a combination of tumbler and lever control on the face of the box and headstock - with one lever available to select coarse pitches. Interestingly, on lathes with the standard speed range, the leadscrew had a pitch of 1/4" while on those with the high-speed option it was 1/2". The box, driven in the usual way by changewheels, was arranged such that, when the leadscrew was in use for threading, the sliding and surfacing feeds drive shaft did not turn - and vice versa. The box was able to generate 80 English (Whitworth) pitches from 1/4" to 56 t.p.i., 68 metric from 0.5 to 11.2 mm and 52 module from 0.25 to 28 MOD - with all common pitches of all types available without recourse to altering the changewheel drive. Eighty rates of power sliding and surfacing feeds were provided, the former from 0.0006" to 0.1356" per revolution of the spindle and the latter from 0.0004" to 0.0959".
Rather unusually, a single apron-mounted lever - rotating around a cylindrical boss cut with a slotted gate - was used to select and engage not only the power feeds but also the opening and closing of the leadscrew clasp nuts; the actions were, of course, interlocked to prevent the use of more than one motion at a time. In addition, the apron was protected by the use of a drop-worm mechanism, this being adjustable for the load at which it automatically disengaged and allowing - no matter how high the cutting load - for both the instantaneous manual release of a feed and the use of an automatic, adjustable trip for the sliding feed when moving towards the headstock. An interesting feature of the apron was its lubrication system which, as the casting was open at the bottom to accommodate the drop-worm mechanism could not use an oil bath; instead oil was directed by wicks that their supply troughs in which they lay. Control of the carriage left and right movements (and left and right-hand threading) was by a reversing mechanism, that used spur gears, built into the headstock.