Wood processing method using a long cone and long cone

摘要

PROBLEM TO BE SOLVED: To provide a long drill capable of being enhanced in the workability of cutting processing and processing precision by enhancing the discharge capacity of cut refuse in a process for forming a deep hole exceeding 300 mm in wood.;SOLUTION: The long drill 10 is constituted by providing two stripe flutes 21 to the weight part 12 with an axial length of 450-1,000 mm having a cutting part 18 made of a sintered bard alloy bonded to its tip part over the boundary from the tip part to a shank 11 and providing the through-hole 25 extending from the shank part 11 to the terminal part of a main body 13 at its axial center position. In the through-hole, an air supply port 26 is opened to the side end of the shank 11 and air jet orifices 27 are opened to the bottom parts of the flutes 21 at the end part of the main body 13. The torsion angle of the flute 23 in the cutting part 18 is 20-40° and the torsion angle of the flute 22 in the main body 13 is 10-15°. The flute 21 is formed so as to gradually shallow from the leading end of the drill part toward the shank 11 in its depth.;COPYRIGHT: (C)2006,JPO&NCIPI