Precisiche Draaibanken Fabriek
(Precise Lathe Factory)
At first of uncertain origin, this backgeared and screwcutting lathe, with its leadscrew running down the centre line of the bed between the ways and a useful top speed of over 3000 r.p.m., is now known to have been made in the western part of the Netherlands "In an attic on a dairy farm in the area of Zoetermeer". With several now found (early 2018), and of unusual design and construction, (including a massive stand), it must have been made in some numbers. One example has been discovered with a badge on the changewheel cover proclaiming "Wolfcraft", a name that might indicate it was marketed by a still-existing company, Wolfcraft, founded in the town of Remscheid by Robert Wolff in 1949. However, other nameplates badges have been found including one, in English, "Made in Holland", another reading "Techn. Handelsonderneming Groothandel Machines Den Haag (The Hague) Holland" and, finally, one with its correct PDF badge.
Although more details are awaited, it appears that the lathe was fitted with an automatic disengage to the sliding feed, a long actuating rod being supported in brackets attached to the front face of the bed and (possibly) moving a large changewheel in and out. What is clear is the depth of the gapless bed, this being in the form a deep, rectangular box and equipped with most odd bed ways - these being two narrow flat tops with V-edges and, outside and below the V-edge, a flat section. The design resembled that used on the American Barnes twin-leadscrew lathe, except that on the Barnes the flat section, instead of being part of the bed casting, was formed from the top of the bed-mounted carriage-drive rack.
Exceptionally long, the cross slide had two T-slots machined, from the rear face, into about one-third of its length - an ideal location for mounting a rear toolpost but of no use whatsoever to hold a vertical milling slide. Of a usefully large diameter - if rather crude engraving - the cross-feed micrometer dial was in aluminium and could be zeroed.
Flange-mounted against the inside left-hand face of the stand, the motor carried a 2-step "A" section V-pulley, the drive travelling externally to a countershaft mounted behind the headstock. Fitted with a quick-release lever to slacken the belt for changes of speed, the countershaft was hinged close to the rear edge of the stand and of the single bearing type with the 2-step driven pulley overhung on one side and the 4-step on the other. The result, with a 4-step pulley on the headstock spindle was (including the use of the eccentrically-mounted backgear), a range of 12 usefully-spaced speed, these starting at a usefully low 35 r.p.m. and running up through 55, 80, 120, 180, 275, 400, 510, 910, 1380, 2640 and 3175 r.p.m. - the speeds and belt positions shown on a cast-aluminium plate fastened to the top face of the front-hinged and rather short headstock belt guard.
Drive to the leadscrew was through a tumble-reverse mechanism and conventional changewheels; however, the arrangement of the bronze clasp nuts was anything but ordinary and arranged in what might be a unique way, being positioned across the bed, in front of the saddle. The inner half-nut appears to have been in permanent engagement and the other pulled into action by rod threaded into it and turned by a front-mounted handle. The tumble reverse mechanism used, as its indent location for the control lever, holes bored into the rim of the thick inner-guard of the changewheel cover - an arrangement used on the American Craftsman 80 (Model 109.21270) and English Murad Cadet lathes.
Able to be set-over for a considerable distance on its very wide base plate for the turning of slight tapers, the tailstock held a No. 2 Morse taper spindle and was provided with a cut-out in the casting through which the operator could read a ruler scale. Unfortunately, the spindle clamping arrangement was of that most horrid kind, a slot closed down by a lever-operated through-bolt. In addition, the tailstock spindle lined up with the headstock only when the casting was set well back on its baseplate - the reason for this not being clear.
Should you know more about this lathe, have any sales literature or own one, the writer would be interested to hear from you..
Some high-resolution pictures - may take time to open