This beautifully constructed in the traditional Schaublin manner, this Swiss-made precision tapping machine enjoyed an automatic return - by means of a mechanical lever switch. The collets used were the Schaublin F4.5, a set of ø1mm, ø1.5mm, ø1,8mm, and ø2.5mm being included - with, presumably other sizes available as well. The unit weighed 15 kg.
This type of machine was intended to help with the accurate and reliable tapping of small holes in watch, clock and instrument mechanisms. Of the "lifting table" type with a fixed head, its solid steel column was socketed into a base plate of cast iron and carried, at its top, the usual two pulleys each of which - by virtue of a special countershaft - rotated in opposite directions. Although the unit lacked screw stops to allow the operator to limit the travel of the spindle, the automatic return negated the need for these.
This tapper was offered for sale by the specialist dealer https://www.nielsmachines.com - a company who always maintain a wide selection of high-class machine tools and accessories similar in character to this one.
Other small tapping machines and tapping attachments of older and modern types include the Aciera vintage, Aciera modern, Dowling, Essex, Herke, Kuhne, Oldak and Apex, Pollard, Sloan & Chace, and Wiest,