A cutter shell for forming holes of improved cylindricality

摘要

A cutter shell for cutting a circular opening in a metal object formed of a tubular boring portion and a head portion. The boring portion has a tubular sidewall and teeth at the forward circumferential end. The sidewall is of thickness not greater than the teeth. The head portion has an outer circumferential perimeter secured to the tubular portion rearward circumferential end, the head portion being attachable to a boring bar by which the cutter shell is rotated. A circumferential abrasive band is affixed to the exterior circumferential surface of the tubular sidewall for engagement with the wall of a hole as the hole is cut in an object by the teeth to smooth and round out the hole for improved cylindricality.