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Portass XL Lathe
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A simple, single-slot arm for the changewheels, round rope-drive headstock pulley and treadle-stand chip tray all help to identify the early (late 1920s) Portass Model XL. Just visible in the picture below is a slight radius to the casting below the left-hand spindle bearing - this was to accommodate the plunger indexing holes for a tumble-reverse mechanism, at the time a most unusual fitting on any Portass lathe.
As an example of a mid-range Portass, the Model XL was, in effect, an early version of the Model S with its bed and headstock cast as one. With a useful 4-inch centre height the lathe was offered in two bed lengths, to give approximately 12 or 16 inches between centres. The first examples were fitted with a 3-step headstock pulley, designed to be driven by a round leather rope, later examples may have had flat-belt drive. The lathe was often supplied fastened to a substantial cast-iron chip tray - and sometimes complete with cast-iron standard (legs) - the headstock-end one of which carried a treadle-operated flywheel. The cut-out in the tray - in line with the headstock pulley - gave clearance for the drive belt--though this would have been restricted to the round-rope driven machines, the flat-belt types being fitted with a rear-mounted countershaft. Both single swivelling tool slides and proper compound slides appear to have been offered, the latter with a T-slotted cross slide. On the single slide version the slide, which was T-slotted, could be fitted into either of the two T-slots formed in the top surface of the saddle. Was this the first ever Portass to be fitted with a tumble reverse to the leadscrew? It would appear so, the short-bed example below having the correct castings in place - but no gearing - while the long-bed version (which must have been marketed as a "De-lux" model) has the complete mechanism in place. However, the tumble gears were of a horribly coarse pitch and must have caused quite a racket when run at speed..

	Portass Model XL. The bed-mounted drilling attachment, driven from a peg carried in the faceplate, was offered by Portass as an accessory for many years. The picture has been heavily "art worked" to improve the machine's rather "as-cast" ex-factory finish. Photographs of a Zyto version here.

	Portass Model XL

	Portass XL. Inexpensive engineering: there is apron on the carriage and the leadscrew "full nut" is bolted to the underside of the saddle. There was no quick-action rack-and-pinion carriage drive but twin T slots in the saddle allowed maximum flexibility in positioning the swivelling tool slide


	Whether the banjo arm carrying the changewheels should be in front of or behind the headstock spindle is open to debate

	Simple but strong tailstock with a proper square-thread, No. 1 Morse taper barrel - and a set-over facility guided by a round bar


	Unfortunately the barrel was locked by a simple pusher screw; however, this was probably a good deal more satisfactory (and with better long-term reliability prospects) than using that other favourite of the inexpensive (and sometimes not so inexpensive) lathe maker - a bolt that attempted to clamp together a split in the tailstock casting

Portass - Long-bed Model XL

Yet another well preserved Portass from the late 1920s to the late 1930s - a rare long-bed Model XL. This example, although modified by a previous owner, still has a variety of features quite at variance with normal Portass practise: the centre height is four inches (unusually generous for the maker) with sixteen inches between centres; bed and headstock are cast as one - though this is in line with the maker's early miniature lathes, the first Model S and the Type V - and fitted with a tumble-reverse drive to the leadscrew. The headstock pulley is obviously intended for a Z-section 10 mm belt (and not a round rope drive) and the spindle nose, with a 1.125" 12 t.p.i. nose is either a modification by a previous owner or a quite-out-of-character move by Mr. Portass. The bronze leadscrew nut is full, and obviously of the maker's type, through the handle on the dog-clutch is not theirs. Oddest of all, though quite possibly a modification, is the well stepped-out cross-slide screw support bracket, the micrometer dials and (for a Portass) the unusually delicate T-slotted cross slide. With the extra rearwards slide travel obtained by the screw bracket, all these fittings combine to equip the lathe perfectly for the mounting of a vertical milling slide, However, even if these items were replaced with ones from an ordinary Portass, the lathe would still appear sufficiently novel to stand out. Just possibly, it might have been built for the then famous tool and machine-tool distributors Buck and Ryan; their badge is attached to the lathe and they would have had the buying power to purchase a batch of machines made to their exact specification. However, having decided upon tumble reverse, one wonders why they did not specify a proper apron with clasp nuts for the leadscrew and a rack-and-pinion hand drive for the carriage ? And could they have neglected to specify at least backgear guards when all other small lathes were decently covered up?
In many ways this models answers most of the usual and annoying shortcomings of the smaller backgeared and screwcutting lathes from Portass - with a few simple additions it would even have made a tough competitor for the Post WW2 Myford ML10 - if not the ML7. If you have a similar machine, please do make contact.