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Continued:
The compound slide rest was strongly constructed and featured a top slide that could be swivelled to any angle; its base, formed as a large circular boss, was engraved with especially clear divisions to 45-degrees each side of zero. With no feed available along the bed, like all plain-turning precision bench lathes, the top slide had, of necessity to be given a relatively long travel - but in this case not as long as it should have been at 41/2-inches.
The micrometer dials, although they read to 0.001'' were tiny, even by the standards of the day, and fitted with the type of twin, closely-pitched, knurled finger-grip rings more commonly found on watchmakers' lathes. Supplied with the lathe to compliment the slide-rest was a bed-mounted hand-turning rest with both long and short Tees.
The tailstock departed from standard precision bench lathe practice by not having its spindle supported along its entire length when fully extended - but was fitted with a micrometer dial and self-eject for the No.1 Morse centre.
Whilst not in in the Stark class for the variety of accessories offered Holbrook nevertheless contrived to list a number of useful items including a range of ordinary and large-diameter draw-back internal and external collets and the necessary closers; a vertical milling slide with both an indexing unit and a high-speed drilling & grinding spindle; a fixed steady; fixed and swiveling grinding heads and a 7-inch diameter faceplate that could be had in plain, T-slotted, or tapped-holes versions - or even lead faced for lapping work. The usual type of Precision Bench Lathe screwcutting attachment was also listed with the changewheels carried on a proper adjustable bracket and the drive to the top slide through a telescopic shaft with a single keyway.
For very precise thread-generating work the lathe was available with a thread-chasing attachment driven by 2:1 reduction gearing. The chaser (threading tool) was carried on a bar slideway running through a long tunnel bored through the back of the headstock casting. The toolholder was fitted with a micrometer dial and screw-adjustable depth stop whilst a tapered stop on the feed mechanism could set to halt the cut at any point. An unusual and timesaving feature of the Holbrook unit was the provision of a weight to automatically lift the chaser from the job on disengagement and return it to the start position. Happily, with the chasing assembly swung back out of the way, the headstock functioned as normal for ordinary turning jobs.
For production work Holbrook offered a complete range of equipment to turn the lathe into a miniature capstan lathe amongst which the main units were: a larger headstock that allowed the use of collets up to 1-inch capacity and almost certainly the mounting (as with the standard head) of both draw-tube and lever-operated collet closers; a bed-mounted 6-station capstan unit to take 3/4'' tooling and a cut-off and forming slide with front and rear toolposts.
To mount the lathe either a pair of simple legs ("standards") and chip tray, both in cast iron, were available or, at considerably extra cost, a rather superior mount with different legs, a wooden tool tray and an integral high-speed ball-bearing countershaft countershaft with fast-and-loose pulleys under foot-pedal control and an additional round-rope "overhead" drive to power the grinding and drilling spindles that this sort of lathe was expected to carry mounted on its top slide.
When equipped for production a special countershaft was supplied that enabled stop, start and speed changes to be made by foot-pedals operating wire links.
The lathe weighed a substantial 200lbs with in basic form but with a compound slide rest..
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