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VDF 18RO, 21RO and 24RO Lathes - Germany

A comprehensive Manual is Available for the
VDF 18RO, 21RO and 24RO Lathes in English and German

VDF Lathes Factory Tour (with German text)


VDF-Drehmaschinen-Werksbesichtigung (mit deutschem text)


""Vereinigte Drehbank Fabriken" (VDF) was a Post-WW2 organisation designed to assist the engineering and sales effort of a group of German machine-tool manufacturers including "Heidenreich & Harbeck, Hamburg", "Boehringer" and "Wohlenberg, Hannover". The organisation created a worldwide marketing operation with their office located in Frankfurt/Main - the exported lathes appearing to have been sold using either the maker's alone, or with just a VDF label - or, sometimes, with both a maker's and a VDF badge.
The first move of the "Association" was to create a unified design of lathe, designed
Einheitsdrehbank, that was built in three dsizes:
E3 by Heidenreich & Harbeck, Hamburg
E5 by Gebrüder Wohlenberg, Göppingen
E7 by H. Wohlenberg, Hannover
Once in production, the "E" lathes were followed by the V Series, these having 20 mm added to the bottom of the E headstock and tailstock castings - followed by a futher increase of 60 mm to make the Type E3H.
Wohlenberg, due to their lower volume production of the larger sizes, was the first of the group to use a new Letter + 3(4) Digit designation in 1963, when their E800V became the V1000 and their W45V the V1180. From this point on, no none-VDF branded machines were produced by Wohlemberg since would have interfered with the larger ones from Böhringer.
In 1964, on January 16, a meeting of VDF staff in Frankfurt decided that the Heidenreich & Harbeck "none-VDF 18R0" would become the E355 and the 21R0 the M430 and during the transitional time to the new designs, the S500 would be carried over as the M530S. In addition, the none-VDF 42D became the E400 and 48D V500.
Although the companies benefited from cross-fertilisation of ideas and common research (as many automobile companies have for many decades), each plant continued to build its own range often in size and specification similar to those made by others in the group.
In addition, many machines enjoyed what might be called a flexible specification, being built to a customer's specific requirements - one example being the basic versions intended for repetitive work on parts of limited size. These models were usually bereft of a tailstock and fitted with headstocks and feed gearboxes that had just four rates of speed and feed respectively - though the makers did offer to change this set-up if required. While strong, accurate lathes, they are obviously not as capable as the regular versions and are quite unsuited to general workshop tasks; in reality, few survive for, once worn out, they would have been scrapped. Many models were also offered with a choice of a plain bronze or roller front bearing, the former sometimes favoured by toolrooms where accuracy was considered more important than very high speeds. However, the only drawback to an older lathe fitted with plain bearings is the expense and difficulty of finding and then replacing them - a roller-bearing model is, in comparison, very much easier to keep running as bearings should be available off the shelf.
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Heidenreich & Harbeck 18RO, 21RO and 24RO lathe

Continued:
Built by Heidenreich & Harbeck of Hamburg, the smallest models in the VDF range were the 18RO 21RO, and 24RO with centre heights of 7" ((180 mm), 8.25" (210 mm) and 9.5" (240 mm) respectively. The 18RO and 21RO could be had with between-centres capacities of 500, 750, 1000, 1250, 1500 and 2000 mm (19.625, 29.5, 39.375, 49.25, 59 and 79.75 inches) and the 24RO could be ordered with one extra length capacity of 2500 mm (98.5"). Long-bed versions were fitted with a third foot in the middle of the bed to prevent sagging when under a heavy load
While the RO18 and RO21 were designed and built to handle work within their size capacity, the RO24 was a "stretched" version intended for larger, lighter or more awkward jobs where rates of metal removal were not an important factor - with the added benefit of freeing up heavier machines in a busy shop for their intended purpose. However, although otherwise having the same general specification of the smaller models, the 24RO was, to help its intended purpose, equipped with a stronger saddle and cross slide.
Both standard and models with increased accuracy were available, the latter to the DIN standard 8605 but on straight-bed lathes only (i.e. without a gap) and up to 39 inches (1000 mm) between centres These superior models could be had with or without a high-precision leadscrew, this being made to a guaranteed maximum pitch error of just 0.0008" or 0.0004" over 12 inches (0.02 mm or 0.01 mm over 300 mm) Whether the increased accuracy was the result of more careful machining and assembly - or just the selection of the most accurate machines from a standard production batch (as Colchester did with some of their lathes) is not known, but, being a cynic, the writer would suggest the latter as being more likely.
First in the range to be put on the market was the RO18, introduced during the late 1940s followed by, in the very early 1950s, the RO21 and then the RO24. The lathes remained largely unchanged until around the early 1960s when numerous improvements were made (and model designations changed as already mentioned), these including an increase in weight of around 8%, the fitting of needle-roller bearings in place of plain bushes on shafts - such as lever pivots - and modifications to the headstock and its lubrication system.
Motor power varied, the makers suggesting from around 5 to 10 h.p. being necessary, the early standard models listed as needing 5.5 h.p. while publicity material hinted that later versions really needed 7.5 h.p. Fitted with a No. 4 Morse taper on all versions, on early models the headstock spindle was bored through 50 mm and fitted with a DIN800 threaded nose, later machines being larger at 56 mm and usually found with the much more supportive and safe short-taper DIN 55022 - this version using the same angle as the well-known American-designed CamLock type.
While it is believed that the models made in the 1940s and early 1950s had two plain spindle bearings, all others had a double-row taper roller at the front and a single row at the rear - though the option did remain to have an adjustable plain bearing at the front; axial thrust being taken by a ball race. Gears built into the headstock were in a heat-treated, ground-finished alloy steel and held on multi-spline shafts running in roller bearings. Control was by two levers, one mounted on the headstock, the other pivoting from the right-hand face of the apron and travelling with it. Both levers were of the "safety" type i.e. they could not be accidentally nudged into engagement instead, they had to be pulled away from a spring-loaded, indented position before being turned to start the lathe. Forward and reverse drive was through a multi-disc clutch with, for stopping, a band brake, this simple device being replaced on later models by a much more effective, powerful and automatically applied electromagnetic type that could bring an unloaded spindle from maximum speed to a halt in around two seconds. Spindle speeds varied over the years with a typical, early specification, being twelve in a choice of three ranges: 17 to 750 r.p.m., 23.5 to 1050 r.p.m. and 33.5 to 1500 r.p.m. At extra cost two high-speed set-ups were also available, both requiring a more powerful motor of up to 10 h.p. The catalogue specification of the first type gave a range 45 to 2000 r.p.m. while the second, not listed in the charts, ran from 1400 to 4000 r.p.m. and was described in the text as "
Special" and intended for "...the use with ceramic tools or the machining of materials such as copper and plastic." Rather unusually, the headstock's front bearing was air cooled by a fan carried on the spindle with filtration taken care of by three units mounted at the left-hand end of the headstock - these being similar to the oiled wire-mesh filters found on compressors or, typically, on cheaper two-stroke motorcycle engines as made until the 1960s.
To bring the feed and screwcutting rates into a usable range, the slower of the two high-speed versions had the ratio of the changewheel gearing to the screwcutting and feeds gearbox halved, while the "Special" had no screwcutting facility at all - and also lacked the spindle-reverse mechanism. Motors could be flange mounted against the outside left-hand face of the headstock, or foot mounted at the back of the headstock-end bed plinth - drive to the headstock input pulley being by three V-belts. Lubrication was taken care of by a pressure pump that distributed filtered oil through pipes to the required locations - earlier machines being fitted with a centrally-positioned manifold above the gears from which the pipes ran; later models lacked the manifold and had revised pipework..

A long-bed Heidenreich & Harbeck 18RO, 21RO and 24RO lathe with a central supporting bed foot

Heidenreich & Harbeck VDF RO24 - the largest in the RO Series

In the bed store;: time for a quick fag and a fiddle with a screwdriver to look busy before that photographer guy arrives

A standard, late-type headstock without the top-mounted oil-distribution manifold and with revised pipework. In the centre can be seen the electromechanical brake and, top left on the lower shaft, the forward and reverse spindle clutch

The "Special" headstock with a fan-cooled front bearing.
At extra cost two high-speed set-ups were also available, both requiring a more powerful motor of up to 10 h.p. The catalogue specification of the first gave a range 45 to 2000 r.p.m. while the second, not listed in the charts, ran from 1400 to 4000 r.p.m. and was described in the text as "
Special" and intended for "...the use with ceramic tools or the machining of materials such as copper and plastic." Rather unusually the headstock's front bearing was air cooled by a fan mounted inboard of it on the spindle. Filtration was taken care of by the two black units seen at the left-hand end of the headstock, these being similar to the oiled wire mesh filters found on compressors or, typically, older two-stroke engines as made until the 1960s.

Touching up the paint finish

A lathe fitted with taper turning incorporating a T-slotted cross slide carrying a two-station rear tool post. Note the very ordinary standard triangular tool clamp - a rather prosaic unit to be found on such a high-class lathe. However, some did incorporate one possibly unique feature, a rectangular plate, able to be swivelled around the mounting stud, against which the clamps levelling screw rested - the idea being, presumably, to prevent marking the top face of the tool slide.

A carriage fitted with the optional power-feed unit that provided rapids for both sliding and surfacing feeds. Automatic disengage stops were fitted to each feed, these being equipped with micrometer screws. All micrometer dials - for the cross and top-slide feeds and the carriage handwheel - were given an anti-glare, satin-chrome finish with the option of dual metric/English engravings. Pivoting from the right-hand face of the apron was a control duplicating one on the headstock and used to electrical start, stop and reverse the spindle. The levers could not be accidentally knocked into engagement - a cause of some serious accidents before the 1950s - the operator needing to first pull them away from spring-loaded, indented positions.

A rather prosaic fitting for such a high-class lathe, the simple triangular-shaped tool clamp assembly fitted as standard did have one unusual (possibly unique) feature: a strip of steel held in place by the toolpost stud formed a resting platform for the clamp's levelling screw - the aim being, presumably, to prevent marking the top surface of the tool slide.


The No. 4 Morse taper spindle of the tailstock was hardened, engraved with ruler divisions, ran in a honed  bore and was locked by a power "split-barrel" clamp. The tailstock was locked to the bed using the action of  lever-turned, cam-shaped cross shaft -  with later models having an additional draw-bolt and clamp plate (as above) to resist the forces encountered during very heavy work). To turn the head of the bolt a special self-hiding spanner was provided.

Static and dynamic stability being tested

Fully equipped: lever-action collet closer, hydraulic copying with template holder, tool back-out attachment and a power driven capstan slide

A large electrical cabinet was provided with plenty of room for additional control elements


A comprehensive Manual is Available for the
VDF 18RO, 21RO and 24RO Lathes in English and German


VDF Lathes Factory Tour (with German text)


VDF-Drehmaschinen-Werksbesichtigung (mit deutschem text)

lathes.co.uk
VDF 18RO, 21RO and 24RO Lathes - Germany

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