24V motor from bus windshield wipers (1800rpm 0.25Nm)
same steal for the spindle housing
lead screw with nut 13mm x 1 mm pitch
linear bearing
base with a column ( a precision stand for sensors)
spindle bearings
Morse cone reducer from 2 to 1 (later it can be turn into a spindle)
chuck without a key to 10 mm + Morse cone 1
sewing machine belt
Most f the elements needed to this device are easily available in shops with used machine tools. The lower spindle bearing is double row oblique, while the upper one is single row.
An useful tool is a Proxxon mini-lathe and a milling machine.
The drill itself works extremely quietly. The maximum beating is under 0,01mm (it mainly depends on the quality of the drill bit).
The resolution of drill depth is 0,01mm.