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Randa/Winfield 3" x 20" Model "R"
For an inexpensive machine the Randa (and its various re-brandings) was reasonably well specified: the 3-inch centre height by 10-inch between centres machine could be had as two distinct (Winfield) models: the better-equipped 20-inch between centres "R" and the very much more basic "H" (a model listed by Randa as their Type "A"). The 90 lb. "R" had a bed and headstock cast as one unit and with a foot at both headstock and tailstock ends. The 6 : 1 ratio backgear was a full-width type mounted on an eccentric engagement shaft and with cast-iron guards; the gears were in steel with the bullwheel locked to the 3-step flat-belt pulley by a quick-release, spring-loaded pin. Tumble reverse was fitted as standard and proper double clasp nuts (running in V-guides) were used to grip the leadscrew - with the latter carrying a "balanced" handle on its end. A short cast-iron guard was bolted to the left-hand side of the apron to afford the leadscrew some protection from swarf and dirt. Instead of a rack-and-pinion the carriage was driven along the bed by a gear that acted directly on the leadscrew (a method still employed into the 1980s on the Myford ML10) the only advantage of which was the engraving of marks on the handle's collar that acted as a thread-dial indicator. The 1.125-inch diameter spindle ran in simple split bronze bearings, was bored through 5/8" with its 1.125" x 12 t.p.i spindle nose carrying a No. 2 Morse taper socket. Whilst early versions of the "R" had a rather short 3 T-slot cross-slide later models had a slide some 2 inches longer with an extra T-slot and a greater travel. Both cross and top-slide screws were square-section and ran directly in the castings without the benefit (to subsequent owners) of replaceable nuts - nor were there any micrometer dials. The tailstock carried the expected No. Morse centre and (on examples seen) could not be set over for taper turning. In the early 1930s the "R" cost £7 : 15s : 0d. Complete with faceplate, catchplate, chuck backplate and a set of 10 changewheels. A later, slightly heavier (110 lbs) version of the "R" (listed by the makers as a "Heavy Duty" model) had its headstock mounted as a separate unit with the centre height raised 35/8" - but the between-centres capacity reduced slightly to 18 inches. The saddle was better supported by the use of small wings at each side, the tailstock was considerably beefed up with its spindle diameter enlarged sufficiently to carry a No. 2 Morse centre and a separate sole plate fitted that allowed the top to be set over for taper turning. The increase in centre height allowed a longer changewheel bracket to be fitted that enabled a double instead of single compound gear train to be set up reduction that gave the carriage a much finer rate of feed whilst also permitting a wider range of thread pitches to be generated.. Continued below: Shown below, the Model "H" was of similar appearance to the "R" but differed in almost every detail of its construction. It could be ordered as either a 12-inch machine with a cantilever bed or as a 20-inch between-centres model - in which case a foot was provided at the tailstock end so the owner could do his best to introduce distortion as he bolted it down to an uneven wooden workbench. The headstock, cast integrally with the bed, carried split bronze bearings in which ran a 1-inch diameter spindle bored through 3/8" with a 1" x 12 t.p.i nose and No. 1 Morse taper socket. A simple 6 : 1 backgear assembly (in cast-iron) was clustered at each side of the left-hand headstock bearing and mounted on an eccentric shaft. No tumble reverse was fitted (nor offered as an extra) and the engagement of the leadscrew was (as standard) by a simple (spring and ball-bearing) snap-in-and-out ball-ended lever operating a single-sided nut. Whilst the long-bed version was illustrated fitted with a proper compound slide rest the short bed model was shown with just a single tool slide mounted on a small boring table with two 2 slots. Both feed screws, as on the "R", were bereft of micrometer dials and their square-section feed-screws ran direct in the castings. The lathes could be ordered with various options including an upgrade to proper leadscrew clasp nuts, a compound slide rest on the short-bed model, a cast-iron stand and both ceiling and bench-mounted countershaft units - though the latter had no form of belt-tension adjustment other than something rigged up by the owner himself. A "foot-motor" was also listed and consisted of a self-contained floor stand with flywheel and treadle that an owner could position beneath his own workbench. Priced at £5 : 10 : 0d the Model H was offered as standard in short-bed form complete with a compound slide rest, 6.5-inch faceplate, 3.25-inch drive plate, a part-machined chuck backplate and 10 changewheels. The long-bed model, with similar equipment, was listed at £19 : 18 : 6d. An extra 8 shillings bought the advantages of a double clasp nut on the apron..
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