The Petermann No. 0 automatic latheis a fine example of a machine type conceived in Switzerland for the mass production of tiny watch parts.
The pre-WW2 No. 0 was the smallest ever Petermann model and intended for material up to 4 mm diameter in brass and 2.5 mm in steel.
By combining headstock and tool movements, cam shapes, cam timing and with various types of cutting and forming tools (and by mounting accessories) the lathes could perform miracles of miniature production engineering.
The longitudinal feed was obtained by sliding the whole headstock along the bed, at various rates and timings, also under cam control.

-  automatic longitudinal bar feed (1 cam missing) with automatic opening and closing
of the spindle collet
-  large capstan wheel at the front for hand operation of the camshaft
-  4 independent tool holders arranged radially in front of the headstock nose. The 2
opposite holders in lower position are equipped with Petermann's "micro-differential apparatus", i. e. a micrometer with 2 possible settings:
1. setting --> accuracy to within 0.01 mm of turned diameter
2. setting --> accuracy to within 0.001 mm of turned diameter
-  very rare screwcutting attachment
-  very rare screw-head slotting attachments (1 cam missing)
After parting off, the partially-finished screw is supported in a tiny tube on the end of a swivelling arm; the arm brings the screw in front of a circular saw to allow the slot to be made. After this action, the arm moves backwards, a rod pushes the screw out of its holding tube and the finished part tumbles down a brass slide into a hopper
-  weight:  30 kg