Given that, at the time, only a tiny percentage of America's machine tools were made away from the eastern states, Los Angeles, California, immediately after World War Two, might not immediately come to mind as a place where a new manufacturer of miniature lathes might emerge. However, as many thousands of the eastern engineers (who had moved to California during the War to build the ships and planes necessary to prosecute it) stayed on afterwards (and who can blame them) it is perhaps not surprising that a company called Small Machines Inc. was created to manufacture the tiny and very unusual ManSon.
Located at 2010 South Sepulveda Boulevard in West Los Angeles, California, USA, the firm began trading in October, 1946 and made what they boldly advertised as: "The World's Smallest Lathe". If not true in an absolute sense, the lathe was, nevertheless, tiny. Just 93/16" long, 311/16" wide and 63/4" high ( 223 mm x 94 mm x 171 mm) the makers claimed a swing of 2" (51mm) and a between-centres capacity of 3" (76mm) - though measurements of the machine shown below give figures of 2.2" and 3.5". Whilst physically small a more remarkable thing about the ManSon was its appearance - which closely resembled a scaled-down toolroom lathe of the era, along the lines of the American Monarch EE or English Smart & Brown Model A.  So difficult is it to categorise the lathe that the term "working-model" might be considered a fair description; certainly, when worn out, they make a wonderful mantelpiece decoration - at least, for those lucky enough to have an understanding better-half.
Made in die-cast aluminium the combined base and headstock carried a cast-iron V-way bed that was screwed to bosses at each end of the integral chip tray. The headstock spindle, running in self-oiling, porous-bronze bearings, was bored through 3/16" and carried a nose threaded  7/16" x 20 t.p.i American National Fine - these tiny dimensions limited the collet capacity to 1/8" (3mm).
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Featuring relatively enormous saddle wings the aluminium carriage could be moved along the bed by either a hand-operated rack feed or under power from the "leadscrew". The base of the lathe contained a 110 volt motor which drove upwards, via a neoprene "O" ring belt, to a wheel with an inboard gear attached, positioned just below the headstock spindle; the inboard gear drove another attached to the end of the spindle whilst a small gear (on the spindle) drove back down through a "compounded" set of slender, clock-like gears to the 32 TPI leadscrew. Unfortunately, because the leadscrew drive gears were fixed in place and could not be changed, the lathe was not capable of screwcutting; even so, this must be the world's smallest production lathe ever to have been fitted with a power-sliding facility where the entire carriage assembly moved along the bed.
Although it would have been much cheaper and easier to have fitted a plain, parallel type every handwheel on the lathe (including the proper, but miniature cast-aluminium ball-ended "balanced" wheel on the cross-feed screw) was provided with curved finger grips.
Both the cross slide and the saddle it ran on (which was cast in one piece with the apron) were in aluminium. The cross slide gib strip was interesting: a "corrugated" strip of spring steel, designed to be self-adjusting - and successfully so, considering the small forces involved. Examination of the gib strip at the points where it bents over at the ends (to retain it) shows that this area was also touched on a grinding wheel to ensure flatness.
There was no backgear on the original models and the number of spindle speeds, from the fan-cooled motor, was limited to two from double-step pulleys. The machine was finished in grey - and weighed just 10 or 12 lbs (4.5 or 5.4 kg) according to which publicity catalogue you believe; without a motor the weight is, however, only 4lbs 4ozs (1.8 kg).
The lathe was supplied, as standard, with a 11/4" faceplate, two centres, a toolpost, motor and switch and cost $49.75--though this soon rose to $58.50. For an extra $2.25 a single drive dog was supplied, together with a tool bit and test rod. As a comparison, in 1948 the Craftsman "80" 6-inch swing by 12 inches between centres, backgeared screwcutting lathe cost  $42 without a motor - and $55.50 with.
A small accessory kit was also available; originally packed in a wooden box - then a wood-lined, 6" x 4" plastic box - it contained (variously) a 4-jaw independent chuck (stamped with the ManSon name and address), a collet chuck and 4 collets of 1/32", 1/16", 3/32" and 1/8" capacity; a 13/4"-diameter faceplate with eight tapped holes, a tailstock drill-chuck, one centre drill, two lathe dogs (sizes 3/16" and 3/8"), several lathe tools and an Allen-wrench. Similar kits, but with different ranges of accessories, were also produced. Depending on the date of manufacture, the 4-jaw chuck was also known to have been supplied in a larger size, with an aluminium body, but without any maker's identification.
At first no 3-jaw chuck was offered, but this was a common failure amongst the makers of small lathes for any sub-2" diameter 3-jaw has always been a difficult to produce economically, yet accurately, on a production basis. The delay in obtaining a suitable 3-jaw was, however, short-lived, for with the introduction of the DuoLathe in 1948 a 3-jaw self-centring chuck was offered as an optional extra for only a few more dollars than the independent 4-jaw. Today, many enthusiasts for tiny lathes fit a suitably-mounted Jacobs "tailstock" chuck on the headstock spindle; they are very accurate and, whilst hardly as versatile as the real-thing, can be surprisingly useful. Unfortunately, the ManSon lathe is so minute that only the shortest version of the smallest Jacobs chuck is suitable.. It is never long before the owner of a miniature lathe realises that there is a need for collets if really accurate work is to be turned out and, with the arrival of the DuoLathe model, with its ball-bearing supported spindle, this also became possible.
Was the ManSon a practical proposition? One owner writes: "It is possible to take a cut so small that the shavings appear to be the size of a human hair in one long string without breaking (if you have a good sharp tool) this is imperative for this machine. The maximum cut you can take is only about .006 to 010. inch but if you work within the unit's limits it is a very fine addition to any workshop."
If you have a Manson of any type the writer would appreciate any comments about its specification, performance and a note of its a note of its serial number.

The apron had gearing which gave a "correct" movement of the saddle as the handwheel was moved. The clasp nut was one-sided - and without a compensating thrust pad; however, for the forces involved, it was perfectly adequate. Every handwheel on the lathe (including the proper, but miniature, ball-ended "balanced" handwheel on the cross-feed screw) was fitted with gracefully-shaped finger grips.

Look closely at the bent-over tongue of metal protruding from the end of the cross slide; it appears to be a simple strip of metal - but is, in fact, a very-well made piece of "corrugated" spring steel which acts as a form of self-adjusting gib strip. Note how the cross-feed handle and the boss that abuts against the face of the apron are cast as one piece.  In a design reminiscent of the Rivett lathe the handle was secured to the shaft by a screw which ran down the length of the shorter cross arm.

The complete carriage assembly with the apron and saddle cast as one. The screw securing the cross-feed handle to its shaft can be clearly seen passing down the shorter of the two cross arms.

Looking as though it was carefully scaled from a very much larger lathe, the tailstock was locked to the bed by the action of an eccentric spindle running through the length of its base.

On the original lathe the outboard drive pulley, with its rounded groove, was positioned below the spindle and carried three brass gears, one small independent - and an integral large/small pair.. The small independent gear drove a larger gear, fastened to the headstock spindle and caused it to rotate. Inboard of the driven gear on the spindle was a much smaller gear, which drove back down to the large gear (of the large/small pair) mounted on the pulley shaft. The small gear of the pair then drove the larger gear of a large/small pair mounted below it - the smaller gear of the latter pair in turn drove another large/small pair - the smaller gear of which then drove a gear on the end of the leadscrew. In other words, a traditional compound-reduction gearing but contained within in a microscopic space and using gears of clock-like proportions.

Standard drive installation showing the simple "open-frame" motor.