PURPOSE: To make cutting tools correspond to a working timber left and right and before and behind and in the vertical direction, and conduct all tenon working by one working unit by installing a large number of the cutting tools in the radial direction of a turret head turned on a horizontal surface and hollow chisel heads in the vertical direction.

CONSTITUTION: A pair of clamping means 3a, 3b are provided at a proper interval, and a working timber W is mounted in the longitudinal direction. A turning body 23 turned on a horizontal surface and revolved in the orthogonal four directions and a turret head 32 having a large number of cutting tools T1-T6 radially and capable of rotating the cutting tools in either one direction in the longitudinal direction or the left and right direction are set up to a moving base 18 controlled and driven in the front and rear and left and right and vertical triaxial directions respectively. A hollow chisel head 36 is fitted downward on the base of the turret head 32. The cutting tool T1 is used in the longitudinal direction when the longitudinal end section of the working timber W is machined, and the cutting tool T4 is employed in the left and right direction when an intermediate side face section is machined. When a square hole is machined to a top face section, the downward hollow chisel head 36 is used.