Shown on this page are examples of the early-type (1940s to early 1950s) Harrison L5 (for details of the full range and its development, click here). The first example pictured had a distinctly old-fashioned style of bed (the section beneath the gap swoops down to retain strength), and a plain-bearing headstock with a domed cover that  reached down to the centreline of the bearings and, instead of being bolted in place, simply rested in a recess. Although this design of cover was necessary to allow the headstock bearing bolts to be undone, one might imagine that if oil instead of an oil-and-grease mixture was used for lubrication leaks would have been a serious problem. The clutch was operated by a long horizontal rod that ran the length of the bed and connected through a clevis pin on the headstock whilst sliding through a guide, supported on a tall bracket, at the tailstock end (although this fitting was not shown in all publicity pictures).
The very first models had enormous (non-zeroing) micrometer dials, cheaply and effectively achieved by engraving the division marks into the flat rims of the cross and top-slide handwheels. Stalks extending from slides' end brackets reached up to the inner edge of each handwheel to provide a flat surface into which a zero mark was engraved.  Later machines, probably from 1948, were fitted with Timken roller bearings in a much more rigid, box-form headstock that also allowed the fitting of a conventional, bolt-on, shallow headstock top covert that guaranteed better oil tightness. At around the same time conventional satin-chrome zeroing micrometer dials were fitted; these were  of decent size and fitted with a thin, knurled ridge to aid changes of setting by oily fingers. This second version of the lathe can be distinguished from subsequent models by full-circle (but non-engraved) handwheels a spring-loaded, bronze-lever, power-feed engagement handle on the apron and a bolt-on cast-aluminium changewheel guard.
Instead of being fabricated from heavy sheet steel (as on all later versions) the stands on early machines were either full length and made of cast iron or, more commonly, with a box-section cast-iron plinth under the headstock end of the bed and a simple leg under the tailstock. At the back of the headstock support was a pair of cast-in motor-mounting brackets in the form of long vertical T slots. However, the latter were soon abandoned and replaced by adjustable bolt-on mounts with pusher screws that made the fitting of different motors and the setting of belt tension a far easier task.
Besides the geared-headstock models Harrison also made, to meet a demand from factories equipped with overhead line shafting,  batches of machines with open flat-belt drive "cone" headstocks..

The first L5, circa 1940-1945, had a distinctly old-fashioned pattern of bed (the section beneath the gap swoops down to retain strength), and a plain-bearing headstock with a domed headstock cover that  reached right down to the centreline of the bearings. The clutch was operated by a long rod running the length of the bed at headstock level - a system that was used until around 1947.

Second-generation (mid to late 1940s MK. 2 L5) with a deeper and stronger bed beneath the gap created by  tripling the length of the headstock-end foot, a full cabinet stand fabricated from heavy-gauge sheet steel, a redesigned roller-bearing headstock carrying a shallower, bolt-on top cover and a short rod-type clutch lever. This version can be distinguished by its full-circle handwheels (without the micrometer marks), conventional zeroing micrometer dials and large combined belt and changewheel bolt-on cast-aluminium guard with curves on its forward-facing surface.

The headstock, always fitted with a clutch and combined friction brake (which mades operation by a single-phase motor much easier and more reliable) had a range of eight spindle speeds. Although the picture above shows a later L5/L5A headstock with the stiffer casting and "safety" high/low-speed lever, the arrangement of the gears within models from the early 1950s was identical.

Very early plain-bearing L5 from around 1944 showing the first type of plain-bearing headstock. To allow access to the spindle bolts the front quadrant of the headstock was completely cut away and the domed-shaped headstock cover (that  reached right down to the centreline of the bearings) simply rested in its recess instead of being bolted down

The spindle ran on a pair of pre-loaded, opposed Timken taper roller bearings at the front and a single-row ball bearing at the rear; the main double gear which slid along the spindle was cut from a single forging and slid on a seven-splines - the complete assembly being dynamically balanced. The gears were all hobbed from the solid, shaved, induction hardened and honed to produce the correct tooth form. The bore through the spindle of the original L5 was a little tight at 0.9125", but when the larger L5A lathe (11-inch swing) was introduced its spindle, with a 1.375" hole, was offered an option on the smaller machine - but I yet to find one so fitted. Besides the two sizes of screwed spindle the American L00 (L zero zero) taper nose was offered as an option and always featured the larger-bore hole.

Doubled-walled, the apron on all models of the L5 employed a push/pull button to select either power sliding or surfacing while the power feed engagement lever, below the centre of the apron, was spring loaded and could be snapped into and out of engagement even under full load; the design was so simple, effective and easy to use that it was adopted across the entire Harrison range.