email: tony@lathes.co.uk
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Centrix Micro Lathe

Information about the Centrix is sought: if any reader can assist,
the writer would be very pleased to hear from you


Looking, in some ways,  rather like an improved and strengthened Adept or modified Perris lathe, the English-built Centrix Micro also resembled the early Flexispeed models - though if there was ever any connection between the various companies is not known. Manufactured by Centrix Precision Products in Shoreham-by-sea the lathe exhibited a decent cosmetic finish with the neat, knurled-edge and plated handles on the compound slide-rest, leadscrew and tailstock being handsome and easy to grip. Both headstock and countershaft spindles ran directly in their surrounding (cast-iron) metal - an excellent, low-cost solution providing the shafts were hardened - and fitted with what looked like simple plastic thrust washers. The split headstock "bearings" could be closed down slightly on the shaft and, although the two model illustrated below have survived in splendidly original condition, there must have been many examples consigned to the scrap bin when the owner's over enthusiasm with a spanner snapped the bearing caps. The oil holes in headstock and countershaft where simple drillings, with no form of cover to prevent the ingress of swarf or dirt. As an option backgear was available, but added considerably to the price and few examples can have been so equipped.
With the saddle and apron cast in one piece the carriage was driven along the cantilever-form, gap bed by an "overhung" leadscrew held within a bearing at the tailstock end of the bed and acting through a "full" nut fastened to the apron. The leadscrew thread was an ordinary left-hand BSF thread that, although it provided a very fine feed, was not as effective as an Acme form at providing an easy motion under load, nor at resisting wear as well. Like the Adept and some other small lathes, the tool thrust on the saddle was taken out on the back of the bed against an adjustable gib strip - not the best engineering solution (the thrust should be against a solid face) but one that would have worked well enough considering the small forces involved. Happily, the slide rest was of the compound type and the handwheels, instead of having handles were fitted, Flexispeed-like, with large diameter, knurled-edge wheels. The cross slide carried T two slots that permitted the mounting of a vertical-milling slide and a repositioning of the top slide to assist with the machining of awkward jobs.
Fitted with a proper eccentric bar and handwheel to lock it to the bed, the tailstock carried a thread on the end of its barrel that matched that on the headstock; a simple split in the tailstock casting (the crudest of methods) was closed down by an Allen screw to lock the barrel.
Simple but effective, the countershaft unit was bolted to the back of the lathe bed immediately beneath the headstock. Because the forces involved were so low, the belt tension was set not by a complicated, over-centre adjustable locking mechanism but simply by tightening the bolt that acted as the swing-head hinge pin - an idea also used on some models of Lorch L-Series lathes.  Unfortunately this was both an awkward and not altogether successful solution, owners reporting that, unless set "just so" belt slippage was a constant problem. While the large countershaft pulley was just an unnecessarily and overlarge M-section unit by Picador, the 3-step was specially-made and took a narrow Z-section V belt. Spindle speeds with a 1425 rpm motor would have been (depending on the motor and countershaft pulley sizes) approximately 200, 400 and 800 r.p.m.
Centrix also manufactured a very interesting wood-turning lathe. This was an all-aluminium machine with steel inserts for the bed ways and available with a neat planer, saw bench, bowl-turning attachment and horizontal belt sander..


A plan view of the lathe showing the cross slide with two T slots - into either of which the swivelling top slide, held by just one bolt, could be secured.

In this rear view the clamping bolt for the tailstock offset can be seen as well as the simple split in the tailstock casting which was closed down by an Allen screw to lock the barrel. Like the Adept and some other small lathes, the tool thrust on the saddle was taken out on the back of the bed against an adjustable gib strip - not the best engineering solution (the thrust should be against a solid face) but one that would have worked well enough considering the small forces involved.

The 3-speed, V-belt drive countershaft was neatly built on to the back of the bed with crude belt tensioning by tightening the bolt that acted as the swing-head hinge pivot


email: tony@lathes.co.uk
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Centrix Micro Lathe

Information about the Centrix is sought: if any reader can assist,
the writer would be very pleased to hear from you