Disclosed is a tap driver for rigid tapping, which includes predetermined
tension and compression factors to self-synchronize the tap driver. In
the preferred embodiment, the tap driver includes helical coils imparted
in the tap driver body which allow the attachment body to synchronize
axially in response to a force of a predetermined magnitude imparted on
the tap. An additional embodiment of this invention provides such a tap
driver body wherein the body allows for lateral flexure and movement to
compensate for feed error and location error.