A machining tool is a machining tool rotated about an axis and is provided with a machining blade portion having a rake face and a machining blade, wherein in a case where the rake face faces and is parallel to an virtual plane including the axis, the rake face is arranged at a position shifted from the virtual plane in the direction opposite to the rotational direction of the machining tool.

A machining tool is a machining tool rotated about an axis and is provided with a machining blade portion having a rake face and a machining blade, wherein in a case where the rake face faces and is parallel to an virtual plane including the axis, the rake face is arranged at a position shifted from the virtual plane in the direction opposite to the rotational direction of the machining tool.

A step drill and a manufacturing method for a step drill in which cutting performance of a cutting edge of a step portion can be enhanced are provided. A groove includes a first ground portion forming an area embracing a second cutting edge of the step portion and a second ground portion forming an area on the heel side of the step portion relative to the first ground portion. Therefore, a convex blade part can be formed on a first cutting edge by performing grinding with the first ground portion and the second ground portion intersecting with each other. That is, it is possible to form the second cutting edge into a desired shape during grinding of the first ground portion. Therefore, cutting performance of the second cutting edge can be enhanced.

A step drill and a manufacturing method for a step drill in which cutting performance of a cutting edge of a step portion can be enhanced are provided. A groove includes a first ground portion forming an area embracing a second cutting edge of the step portion and a second ground portion forming an area on the heel side of the step portion relative to the first ground portion. Therefore, a convex blade part can be formed on a first cutting edge by performing grinding with the first ground portion and the second ground portion intersecting with each other. That is, it is possible to form the second cutting edge into a desired shape during grinding of the first ground portion. Therefore, cutting performance of the second cutting edge can be enhanced.

The invention relates to a step drill having a shaft section extending along a longitudinal axis of the step drill and a cutting section with a cutting tip, and having a chip-breaking geometry which comprises a concavely curved surface and is configured such that ribbon chips are broken on the concavely curved surface during rotation of the step drill, whereby the chip-breaking geometry is disposed on a reaming step of the step drill.

A vertical-edge double-step sawtooth cutter for preparing high-quality holes of composite material and thereof hybrid stack structure, and has three parts which are a major cutting edge region A, a minor cutting edge region B and a shank region C. The minor cutting edge region B comprises a step vertical-edge region D and a sawtooth cutting region E. This has the step structure and the sawtooth structure which is distributed in the first step, has a recutting function at the inlet and a reverse cutting function at the outlet in the direction opposite to the main cutting motion. The cutter has the vertical edge structure distributed in the second step, and the angle of the second step is a negative value, thereby realizing chip breaking and crushing, reducing scratch to the upper-layer composite material and metal hole walls.

A drill bit includes a shank and a body portion defining a plurality of axially stacked, progressively sized steps. The steps include a first step and a terminal step. The first step defines two tip flutes each disposed at a tip flute angle. The body portion defines a body flute extending through the steps. The drill bit also includes an indicator band formed on a portion of the body flute and a portion of an outer surface of one of the plurality of steps.

A method employing an apparatus in conjunction with a hammer-drill to penetrate composite metal and non-metal structure or structures including, for example, thick metal or rebar encountered during concrete, rock or masonry boring operations without requiring a change in drill equipment.

A method employing an apparatus in conjunction with a hammer-drill to penetrate composite metal and non-metal structure or structures including, for example, thick metal or rebar encountered during concrete, rock or masonry boring operations without requiring a change in drill equipment.

A drill bit includes a shank and a body portion defining a plurality of axially stacked, progressively sized steps. The steps include a first step and a terminal step. The first step defines two tip flutes each disposed at a tip flute angle. The body portion defines a body flute extending through the steps. The drill bit also includes an indicator band formed on a portion of the body flute and a portion of an outer surface of one of the plurality of steps.