Abstract: This invention is directed to an ultrasonic machine and its method of operation. The machine has a main shaft rotatably supported in a housing, a machining head attached to one end of the main shaft, a piezoelectric transducer provided on the machining head, and a tool attached to an end of the machining head. The machine also includes slip rings provided on the periphery of either the machining head or the main shaft as an input terminal, brushes being in slidable touch with the slip rings and connected to a power source, and a brush detach apparatus for detaching the brushes from the slip rings to reduce friction and disconnect ultrasonic operation. The tool is rotated and pressed onto the work, hence starting a boring operation. After the rotation forms a pre-determined depth of a bore, the tool is ultrasonically vibrated to bore further into the work. The method and apparatus are particularly suited to boring small holes in ceramics and the like.