A tapping tool comprises a threaded portion and an upper gripping shank,
and presents an axial bore which has its base wall proximate to the end of
the threaded portion and opens at the end of the shank, there being
present in proximity to the base wall at least one duct which connects the
bore to the outer surface of the threaded portion, and makes available on
one side of the outer rim of the duct a sharp edge for removing the
material, which then by passing through said duct collects inside the
bore.