Introduced during WW2, the 121/2" x 20" Rivett 1020 was, after a short production run,  withdrawn from sale being replaced first by the rare 1020R and then the more common 1020S (20 inches between centres) and 1030S (30 inches between centres. The designer of 1020S is believed to have been Italian and the first batch of lathes was assembled and tested by Leon E. Levasseuring. The lathes, built from 1949 to 1961 and known as the Steelway Precision Toolroom Lathe, were aimed at the same market segment as the (then) class leader, the superb Monarch Model 10EE - and so, unsurprisingly, resembled that model in their appearance. As was common at the time to many other makers, the lathe was also offered as a "manufacturing" or "production" type, the 1020M, this version lacking the (expensive) leadscrew and probably equipped with a different speed range. Superbly made, the toolroom versions boasted a comprehensive specification with a 12.75" wide bed, fitted with hardened steel ways, and enormously long saddle wings that gave a contact area of 55.5 square inches.  Weighing around 3900 lbs (1.6 tons) and 4200 lbs (1.875 tons) respectively  the lathes sat on a substantial cabinet stand of cast iron and held a cushion-mounted drive system that formed a complete unit and that could be maintained through large openings in the end and the back of the stand - or withdrawn completely through an end door.
Drive was by a 5 h.p. 3-phase 1750 r.p.m electric motor carried an expanding and contracting pulley, the opening and closing of which was activated by a small motor controlled by push buttons, marked Fast and Slow, positioned to the right of the screwcutting gearbox, that gave two variable-speed ranges. The drive from the motor passed to a shaft carrying a dog-clutch arrangement that allowed the motion to continue either to its end - and so drive a triple V-belt connected to the backgear assembly in the headstock - or to be passed across to a parallel countershaft that directed the drive, via a 3-step V-belt, straight to the end of the headstock spindle. The lower backgear ratio was 12.5 : 1 and gave speeds from 22 to 200 rpm while the higher ratio was 6.25 : 1 with speeds from 44 to 400 rpm. This arrangement ensured that the V-belts did not lose their efficiency, their running speed never falling below 300 feet per minute. Thanks to Tom Hammond and his dedicated Rivett web site, we know now that two other versions of the lathes were built, these being the 1020F and 1030F and constructed during the Rivett Company's final years when a subsidiary of Leland-Gifford Co. The centre height of the "F" was increased to give a swing of 13.5 inches and the tachometer changed from a mechanical to electronic type.
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Massively built and enormously strong, the rounded headstock casting had, to ensure minimum weakening of the structure, the smallest possible inspection hatch in the top. It contained gears that were all machined from heat-treated alloy steel and either shaved or ground finished. The 1.25" bore  main spindle carried an American Long Taper Key-drive nose, size L0 (a D-1 4" Camlock was optional) had no sliding gears and was supported by a centre bearing designed to reduce flex under heavy loads; it ran in super-precision ball races, a double-row preloaded set at the front, a single row at the rear and  a single-row bearing in the centre. The layshaft sliding gears moved on six-tooth involute splined shafts and were supported in either ball or roller races. Rivett was justly proud of their finely engineered headstock and prepared a special display model, taken to machine-tool exhibitions around the country, to explain how it worked. Collets could be fitted either directly into the headstock spindle - in which case the maximum in-bore capacity was 11/8" or a though capacity of 1" (limited by the drawtube) or in a "draw-in" collet chuck by Sjorgen or a Jacobs "Rubber-flex" unit with, in both cases, a maximum pass-through capacity of 13/8". A rev. counter was built into the head - an indispensable aid when using a variable-speed lathe.
Like that used on the Monarch 10EE Toolroom lathe, the screwcutting gearbox used selector knobs on each side of a central turn-push-pull selector. The box, built as a complete, independent unit, could be slid out of its housing in the bottom section of the headstock for servicing or repair. The unit contained an oil sump, fitted with a sight-glass level indicator, from which the gears and bearing were lubricated by splash whilst the idler gears, on the external drive, ran in grease sealed bearings. All the gears associated with the box were manufactured from heat-treated alloy steel - and either ground or shaved according to their particular function - whilst the shafts carrying the sliding gears were of the six-tooth involute splined type. A total of 72 rates of feed and 84 threads were available including, so the makers claimed, " …every world standard from 2 to 240 t.p.i." The actual range was: 2,  21/4,  23/8,  21/2,  23/4,  27/8,  3,  31/8,  31/4,  33/8,  31/2,  33/4,  4,  41/2,  43/4,  5,  51/2,  53/4,  6,  61/4,  61/2,  63/4,  7,  71/2,  8,  9,  91/2,  10,  11,  111/2,  12,  121/2,  13,  131/2,  14,  15,  16,  18,  19,  20,  22,  23,  24,  25,  26,  27,  28,  30,  32,  36,  38,  40,  44,  46,  48,  50,  52,  54,  56,  60,  64,  72,  76,  80,  88,  92,  96,  100,  104,  108,  112 and 1 20. In addition, by setting the lever under the rev. counter to "Feed" (which doubled the pitch of the previous twelve threads) the following pitches could be obtained: 128,  144, 152,  160,  176,  184,  192,  200,  208,  216,  224 and  240 t.p.i. A range of metric and other pitches could be obtained by employing different external pick-off gears on the drive from headstock to gearbox.
Bearing more than a passing resemblance in both appearance and function to that on the equally well-made Monarch 10EE toolroom lathe the carriage assembly of the Rivett 1020S was enormously heavy yet moved with silken smoothness along the bed. The leadscrew was reserved only for screwcutting with a powershaft providing a drive for the power sliding and surfacing feeds. Two separate, snap-up-and-down horizontal levers were used to select and engage the feeds with each working through safety overload-protected clutches. A precision carriage stop was fitted and arranged in two parts: a dial-test indicator, mounted on the left-hand edge of the saddle, engaged the rod of a micrometer held in a clamp on the lower face of the headstock - the combination of a positive stop, and a continuous, precision-reading of saddle travel being a most useful feature. The base of the double-walled apron contained an oil sump, with a sight-glass level indicator, from which lubricant was distributed to the bedways and all the apron gears, shafts and bearings by a plunger pump activated by the engagement of either feed. An interesting point (and one overlooked by many designers) was the attempt to minimise deflection by locating the carriage clamping bolt in the middle of the apron.
As might be expected, the compound slide-rest feed screws were of hardened steel, precision ground and ran through nuts that could be adjusted to eliminate backlash. The zeroing micrometer dials were not as large as they might have been on a machine of this class - but were fitted with neat, straight-pull locking screws that did not disturb the selected setting. The cross-feed screw was fitted with a useful ball stop that permitted the retraction and resetting of a threading tool without losing the initial micrometer setting. The penalty for having a neat, flush-fitting dial-thread indicator on top of the saddle was the permanent engagement of its gear with the leadscrew and the need to employ bevel gears to take its drive through a right-angle.
Advertising for the machine summed up its capabilities in this neat sentence:
"It combines the feather-touch sensitivity of an instrument lathe with that heavy-biting ruggedness which carbide cutting tools require."
During the 1940s and 1950s Rivett also produced two plain turning lathes: the 918S  had a 9" swing and admitted 18" between centres (with an infinitely-variable speed drive between 100 and 3750 rpm) whilst a smaller lathe, the 715, had a 7" swing lathe, 15" capacity between centres and used the same drive system but with a very useful speed range from 200 to 3500 rpm..

Massive build yet modest capacity made for a superbly accurate and potentially reliable machine with a long and productive life

The Rivett 1020S bed, 12.75" wide over the ways, was in cast iron, heat seasoned and fitted with ground steel ways hardened to 60 Rockwell C scale. 

The beautifully waisted, chrome-plated, solid-steel headstock control knobs were unmistakably Monarch-like in both appearance and operation.  The nearest control knob in the picture, with settings marked "backgear and open belt", operated a dog clutch on the base-mounted countershaft unit.

To preserve rigidity the inspection plate on top of the headstock was kept to the minimum size. Note the triple V-belt drives.

The screwcutting gearbox was very like that used on the Monarch 10EE Toolroom lathe in both operation and the appearance of the knobs each side of the central turn-push-pull selector. 

The two countershaft units in the base of the stand provided separate drives to the spindle and headstock backgears.  The drive from the variable speed unit passed to the right-hand unit and from there, via a dog clutch, either across to the left-hand unit (and up to the end of the spindle) or up to the lower of the two V-belt pulleys on the headstock - and hence into the backgear assembly.

The Rivett 1020S drive unit was cushion mounted, within the cabinet base, and formed a complete system which could be maintained through large openings in the end and the back of the bed - or withdrawn completely through the end door.
The electric motor carried an expanding and contracting pulley arrangement, the opening and closing of which was activated by a smaller motor controlled by push buttons, marked Fast and Slow, positioned to the right of the screwcutting gearbox. The drive then passed to a shaft carrying a dog-clutch arrangement which allowed the motion to continue either to its end - and so drive a triple V belt connected to the backgear assembly in the headstock - or to be passed across to a parallel countershaft which directed the drive straight to the end of the headstock spindle.

The zeroing micrometer dials were not as large as they might have been on a machine of this class but were fitted with neat locking screws.

Inside face of the double-wall, oil bath apron showing the two separate take-offs on the power shaft  for power sliding and surfacing

A model of simplicity and ease of use. Power sliding and surfacing feeds were each selected and engaged by their own lever and worked through safety overload clutches.

A well-presented display model of the Rivett 1020S headstock assembly. The direct drive 3-step pulley on the end of the spindle - and the 3-step auxiliary drive to the backgear - can be clearly seen.

Ordinary fixed steady of  3" capacity. A larger steady, able to accommodate material 6" in diameter, was also available.

"Accumulator" dial to replaced the standard cross-feed dial. The outer dial, calibrated in thousandths of diameter, had separate numbering for turning and boring operations. The inner dial accumulated and recorded the reading of the outer dial in hundredths of thousandths and in "sixty-fourths".

Taper-turning unit - able to turn tapers of up to 18 degrees included angle and 18" long at one setting. Like the devices fitted to Monarch and Alexander lathes, the setting was through a geared adjusting wheel (not visible). The assembly was normally covered by hinged guards, removed for the photograph.

Universal milling attachment bolted directly onto the cross slide and could be used with the power feeds. The indexing head (shown mounted on the vertical slide) used the same Rivett (6R) collet as the lathe spindle.