A cutting tool (2)in particular a rotary toolis described, having a cutting edge (4) from which a rake face (6) and a clearance face (8) extend, characterized in that a groove (12) is introduced into the clearance face (8) in a region along the cutting edge (4) so that a part of the clearance face (8) is formed as a wear face (14) that extends between the groove (12) and the cutting edge (4) and is bounded by the groove (12) and the cutting edge (4). The groove (12) advantageously limits the wear of the cutting tool (2) in the region of the cutting edge (4) on the wear surface (14), so that overall the frictional forces that occur are kept small and the service life of the cutting tool (2) is extended. Furthermore, a cutting element for a cutting tool (2) as well as a method for manufacturing the cutting tool (2) are described.

A cutting tool (2)in particular a rotary toolis described, having a cutting edge (4) from which a rake face (6) and a clearance face (8) extend, characterized in that a groove (12) is introduced into the clearance face (8) in a region along the cutting edge (4) so that a part of the clearance face (8) is formed as a wear face (14) that extends between the groove (12) and the cutting edge (4) and is bounded by the groove (12) and the cutting edge (4). The groove (12) advantageously limits the wear of the cutting tool (2) in the region of the cutting edge (4) on the wear surface (14), so that overall the frictional forces that occur are kept small and the service life of the cutting tool (2) is extended. Furthermore, a cutting element for a cutting tool (2) as well as a method for manufacturing the cutting tool (2) are described.

A grinding machine of one embodiment includes an abrasive wheel; a rectangular base including a top wall having a central through hole and an upper shoulder; a mounting member secured to the central through hole; an electric motor including a drive shaft passing through the mounting member to secure to the abrasive wheel; first and third workpiece holding units each including a board secured to the base; an adjustment knob on the board; and an L-shaped seat secured to the board and having a transverse channel, a front curved slot, a rear projection pivotably secured to the board, and a pin secured to the board and disposed in the slot; a second workpiece holding unit secured to the shoulder and including a vertical tunnel; and a fourth workpiece holding unit secured to the shoulder and including a vertical tunnel, an adjustment knob, and a fastening member.

A rotary tool, in particular drilling tool, extends along a longitudinal axis and has an end surface; a brad point; and at least one major cutting edge extending outward up to an edge corner. A first free surface segment adjoins the major cutting edge, and a second free surface segment in turn adjoins said first free surface segment. To keep the stress, in particular the wear, low in the region of the end surface, the first free surface segment has a lower average abrasiveness than the second free surface segment.

A rotary tool, in particular drilling tool, extends along a longitudinal axis and has an end surface; a brad point; and at least one major cutting edge extending outward up to an edge corner. A first free surface segment adjoins the major cutting edge, and a second free surface segment in turn adjoins said first free surface segment. To keep the stress, in particular the wear, low in the region of the end surface, the first free surface segment has a lower average abrasiveness than the second free surface segment.

A twist drill for drilling composite materials includes a shank; a drill body; a drill tip having a cutting edge, a chisel edge, and a secondary chisel edge, wherein the secondary chisel angle of the drill tip is 145 to 165 and the point angle is 70 to 100; and a flute extending from the drill tip to the drill body. The flute has a constant helix, and the helix angle of the flute being selected from the range 45 to 55. A method of drilling a composite material comprising fibers uses the twist drill of the present embodiment. Suitably, the composite material is carbon fiber reinforced plastic or glass fiber reinforced plastic, and optionally being a laminate material such that the method comprises stack drilling. Embodiments achieve a combination of good hole quality, good tool life and good hole size spread.

A twist drill for drilling composite materials includes a shank; a drill body; a drill tip having a cutting edge, a chisel edge, and a secondary chisel edge, wherein the secondary chisel angle of the drill tip is 145 to 165 and the point angle is 70 to 100; and a flute extending from the drill tip to the drill body. The flute has a constant helix, and the helix angle of the flute being selected from the range 45 to 55. A method of drilling a composite material comprising fibers uses the twist drill of the present embodiment. Suitably, the composite material is carbon fiber reinforced plastic or glass fiber reinforced plastic, and optionally being a laminate material such that the method comprises stack drilling. Embodiments achieve a combination of good hole quality, good tool life and good hole size spread.