Book 2 — To Prevent Drill from Catching As It Passes through Metal
Reading edition
The regular slope of a drill will cause the cutting edge to catch as it breaks through the metal on the opposite side of the piece being drilled. But if a twist drill is ground more flat like a flat drill, it will not "grab" into the metal as it passes through.—Contributed by James H. Beebee, Rochester, N. Y.
