Tools for the Workshop

The spiral point is a new cutting surface shape, for a standard twist drill, which can be produced by means of the ‘Cincinnati Spiropoint’ drill sharpening machine. It is claimed that a drill with this shape becomes a precision tool which maintains accuracy in hole positioning, eliminates centre punching, produces holes closer to size, rounder, straightcr and burr‐free, increases drill life, reduces drill thrust force required, reduces the need for secondary operations such as reaming and produces less workpiece distortion because of its cooler cutting and reduced thrust force.