BOW DRILLS

I am currently fascinated by bow drills! They are one of the oldest tools used by man, initially for starting fires but also for drilling into beads and stone. Records show bow drills in use by early Egyptians and Romans with evidence of use back to the Stone Age period.

Nineteenth century examples are much more sophisticated in their design and often convey the unique artistic expression of the designer. They are usually constructed in ebony or cocobolo, brass and ivory...all of my favorite materials!

I have completed four miniature bow drills (shown above) as of this posting. The top drill was made by BUCK of London, the ivory-spool drill by EARLANDSEN of New York, the ebony drill (lower left) probably also by BUCK, and the fluted ebony drill (lower right) by HOLTZAPFFEL. As you can see the design and the materials vary significantly just in these four examples. These miniatures vary in length from 2.5" to 4" and each one is fully functional. As an example of design complexity, the ivory-spool drill is assembled from 14 unique parts.

The Erlandsen drill was offered to piano, organ and violin builders in an early 1900's catalog printed by Hammacher Schlemmer & Co. for the price of $9.00. At that time it was the most expensive tool shown in the 66 page catalog, selling at six times the price of a chrome-plated Stanley rabbit plane. This is a good indication of the materials and effort that went into the design and the perceived value of the tool to the builder.

Components of the Buck ebony drill are shown below, but the basic component set is typical of other drills as well. The spool is fixed to the chuck shaft which spins freely within the lower handle section. The upper end of the shaft is threaded, and there is also a small set-screw threaded into the end of the shaft. The knurled brass cap is tightened down against the end of the set-screw to hold the shaft and handle assembly together. The bottom surface of the brass cap becomes a bearing surface, making contact with the brass core of the handle. During set-up the set-screw is positioned to allow the shaft to spin freely within the handle, while limiting the lateral movement of the shaft. Exact details of this adjustment vary by manufacturer, but the precision of the adjustment ultimately defines the quality of the drill. The handle cap provides for user comfort, but also seals the adjustment chamber so as to retain lubricant and prevent wood dust from fouling the bearing surfaces.

I have recently acquired four more full-size bow drills and am anxious to add models of these drills to my collection.