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KOK Lathe
If you have a KOK lathe of any type  the writer would be interested to hear from you

Manufactured in Holland by J. Kok N.V. of 25 van Deventerstratt in Rotterdam, the KOK Model K10 7-inch  (180 mm) swing by 40-inches (1000 mm) between centres geared-head lathe was produced from the 1940s until the mid 1950s.
Cast from a grade of  "Perlite" wear-resistant, heat-treated iron the 10.5-inch wide V and flat-way bed was machined by planning and then hand scraped to its final finish. It had, as standard, a removable gap section that allowed a piece of material 22.5-inches (560 mm) in diameter and 7-inches (180 mm) thick to be turned on the ordinary faceplate. The V-way at the front was arranged with a steeper angle on the inside and a broader face on the outside, an arrangement favoured by some makers in the belief that it was better at both absorbing cutting thrust and reducing wear than symmetrical ways.
Running in parallel bore bronze bearings, tapered on their outside for adjustment by screwed collars, the 1
7/8" (36 mm) bore headstock spindle carried a screw-thread nose - most competing lathes of the same size had, by this time converted to the far more rigid and safe American long-nose taper or CamLock types. The headstock used quiet-running helical gears, cut from the solid and in a tough grade of steel - but not hardened. Mounted on an adjustable plate, pivoted from the back of the headstock end plinth, the standard-fit single-speed motor drove up to the headstock using twin V-belts in a protective housing. Eight speeds, from 24 to 600 r.p.m., were available or, with the optional 2-speed motor, 16 from 24 to 1200 r.p.m. Speeds were changed by three levers on the face of the headstock working through rack-and-pinion gearing; like most machines of the time, the levers lacked a spring-loaded interlock and could be accidentally nudged into engagement. The feed-reverse gears (tumble-reverse) were mounted inside the headstock and so benefited from better support and lubrication from the same supply of splash-distributed oil as the rest of the assembly.
Only one changewheel stud was provided between headstock and the dual English/metric screwcutting gearbox - but this arrangement was enough to provide carriage sliding feeds from 0.00275 to 0.0567 inches of feed per revolution of the spindle, 32 English thread pitches from 2.75 to 40 t.p.i. and 32 metric from 0.5 to 6 mm. Drive from the gearbox turned a power-shaft, to operate the sliding and surfacing feeds, with the 1 3/16-inch (30 mm) 4 t.p.i. leadscrew driven from it by a sliding gear that only need engaging for screwcutting duties. A large thread-dial indicator was fitted as part of the standard equipment and pivoted from a stud screwed into the apron's right hand face. Power feeds were selected by a 3-position, apron-mounted lever with a large, knurled-edge, concentrically mounted knob being screwed in and out to engage and disengage the feed through a friction clutch. Though a safe method of operation (and with a good-sized control) the clutch suffered, like all similar systems, from an inability to instantly (and so safely) snap the drive out of mesh.
With both feed screws operated by balanced handle wheels - and fitted with far-too-small micrometer dials - the compound slide rest used a tapered gip strip on the cross slide and an ordinary loose strip on the top. Whilst a simple 4-way toolpost was included it was an inadequate assembly and, being limited to five indexed positions by a spring-loaded plunger engaging in slots, would have caused the operator endless frustration.
Fitted with a 1 3/8" (35 mm) diameter, 4" (100 mm) travel, ground-finished spindle, the tailstock could be set over on its base for the turning of slight tapers. Unfortunately, instead of a captive handle, it was locked to the bed by loose, self-hiding spanner. However, some compensation was to be had in the spindle lock, a positive, split locking pad instead of a split in the casting closed down by a bolt (a point not lost on the maker's who, unusually, referred to this contrast in design in their sales literature)..

KOK Model 180 7" x 40" lathe circa 1952

Inside the screwcutting gearbox

MAIL   Tony@lathes.co.uk
Home    Machine Tool Archive    Machine-tools for Sale & Wanted
Machine Tool Manuals   Catalogues   Belts   Books   Accessories

KOK Lathe
If you have a KOK lathe of any type  the writer would be interested to hear from you