Machine that cuts the teeth of files by itself
A falling weight drives a toothed wheel and hammer to notch a clamped file blank.
This sheet shows one of Leonardo's automatic tools: a machine that cuts the teeth of a file by itself, as its single caption declares. A file blank is clamped on a horizontal bed at the left; a weight hung from a cord over a pulley at the top powers the mechanism, turning a large toothed wheel that feeds the work forward and lifts a hammer to strike the cutting chisel step by step. At the upper left are separate studies of the chisel and the hammer head. The design converts a steady falling weight into the repeated, evenly spaced blows needed to raise a file's teeth.
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The self-cutting file machine
A file blank is clamped on the horizontal bed at the left. As the mechanism runs, a large toothed wheel at the right both advances the work and raises a hammer that drives the cutting tool, notching the file tooth by tooth.
Powered by a falling weight
The motive power is a weight suspended from a cord over a pulley at the top of the sheet; its descent is converted into the stepwise feed and repeated blows of the cutting action.
Chisel and hammer details
At the upper left, drawn apart from the main assembly, are small separate studies of the cutting chisel and of the hammer head that strikes it.