Horological Drilling Machines

Drilling small (down to 0.1 mm !) holes truly perpendicular into a work piece was made possible by a variety of drilling machines. D-bed lathes could be clamped vertically to the worktable and used in this position for drilling together with a small lever-operated table that fit into the tailstock. The next step up is to mount a lathe headstock onto a column that is permanently fixed onto a heavy pedestal and is again provided with a lifting drilling pad (Figure 1). Alternatively, the drilling spindle may slide up and down in its bearings (Figures 2, 3 and 4). A lever provided for sensitive operation. Larger machines had sliding headstocks, based on the lathe design, like the milling machines (Figure 5). The drills are held in collets. The larger machines are bored for 6 mm or 8 mm collets, the former seems to have been more common. Later horological drilling machines are desined more like today's pillar drills (Figure 6).

There are two machines in my collection currently. Both bear no manufacturer's name. The smaller, and probably older, one could have been made by Boley, judging from the style of the machines in their catalogues (Figure 2 and 3). It takes tiny 4 mm collets. If have set it up on a base with a shop-made idler pulley and a little antique 220 V AC electric motor that I had picked up on the ever obliging Viennese flea-market.


(1) Lorch, Schmidt Co. No. 1 drilling machine based on components from their D-bed lathes. From a 1930s catalogue.	(2) A Boley No. 76b drilling machine from a c. 1910 catalogue.	(3) Small (Boley ?) drilling machine after restoration and set-up.	(4) The small drilling machine as received together with its wooden storage box.	(5) A Boley No. 78 drilling machine from a c. 1910 catalogue.	(6) The Boley BE2 drilling machine from a 1950s catalogue now has an electric motor fitted.

The bigger drilling machine below may have been made by Hauser. I have seen an almost identical one mounted on a heavy base for carrying the motor that had 'HAUSER' cast onto it. It is bored for the standard 6 mm collets. In order to make it operational, I mounted it on a wooden base that houses a 90 W sewing-machine motor. A dimmer allows to adjust the speed.

The machine was basically complete when received, with the exception of a ruler that indicates the boring depth. This ruler is screwed into a hole in front of the spindle and the micrometer drum, which serves as a depth-stop, runs up and down along it. The same arrangement can be seen on the miller from the Musée International d'Horologerie, La Chaux-de-Fonds. In fact, this arrangement seems to have been frequent on Swiss precision toolroom machines and measuring equipment.

Though is was originally painted in the usual machine gray, I re-painted it in a 'bottle' green to match my other other machines. Apart from providing an aesthetically pleasing contrast to the steel and brass/bronce parts, it is easy on the eyes (which is why desk-tops traditionally have a green leather surface).

Jig-boring capability is achieved by adding a small (shop-made?) cross-slide that I happen to obtain with some other lathe stuff. This comes very handy for drilling equal spaced holes etc. An integrated small vice to hold small and flat parts still needs to be made.


Hauser(?) precision drilling machine