Disclosed is a hole cutter including a unit cutting edge, the unit cutting edge including a front surface portion, an inside surface portion, an outside surface portion, and a rear surface portion. The front surface portion includes a first machined surface; and a second machined surface which has a structure which is formed with a surface distinguished from the first machined surface with respect to a first boundary line and is connected to the first machined surface along the first boundary line. The rear surface portion includes a third machined surface; and a fourth machined surface which has a structure which is formed with a surface distinguished from the third machined surface with respect to a second boundary line and is connected to the third machined surface along the second boundary line.

A cutting tool including a body, a blade, a feed shaft, and a locking member. The body defines an axis and is adapted to be received by a spindle of a power tool. The blade is removably supportable on the body and rotatable about the axis for cutting a workpiece. A feed shaft is removably supportable in the body and rotatable about the axis for engaging a workpiece, the feed shaft being mountable in the cutting tool to engage and at least partially restrain the blade. The feed shaft further includes an opening transverse to the axis. The locking member is engageable with the body and with the opening in the feed shaft. Advancement of the locking member into the opening tightens both the blade and the feed shaft to the body.

A cutting tool includes a hole saw, a pilot bit, and an arbor assembly. The arbor assembly includes a shank, a sleeve, a first ball bearing moveable relative to the shank, the first ball bearing engaging the hole saw to releasably secure the hole saw to the shank, and a second ball bearing moveable relative to the shank, the second ball bearing engaging the pilot bit to releasably secure the pilot bit to the shank. The sleeve is moveable to a first position where the hole saw and the pilot bit are secured to the arbor assembly, to a second position where the first ball bearing disengages the hole saw, allowing removal of the hole saw from the shank, and to a third position where the second ball bearing disengages the pilot bit, allowing removal of the pilot bit from the shank.

A quick change tool includes a tool element, an elongate body having a drive shaft and attaching means for attaching the tool element to the body, and a receiving element for attaching to the tool element. The receiving element includes a through-hole for receiving the body by sliding through the receiving element in the longitudinal direction of the body. The receiving element is configured to co-act with the attaching means to lock the tool element relative to the body at least in an axial direction of the drive shaft. The attaching means includes a resiliently movable locking pin arranged spring-mounted in the body. The receiving element comprises a locking hole configured to receive the locking pin therein in a snapping manner. A pin guiding groove extends between a receiving opening of the through-hole and the locking hole for guiding the locking pin from the receiving opening to the locking hole.

A cutting tool is provided that is operable to provide a circular cut or hole in a material or work piece. In various embodiments, a guide member is provided that facilitates alignment of a cutting edge of the invention with a pre-existing cut, hole or aperture. Devices and methods of the present disclosure provide for quick and easy centering of a cutting tool in order to form an enlarged hole that is concentric with a pre-existing hole.

A cutting tool includes a hole saw, a pilot bit, and an arbor assembly. The assembly includes a shank having a first end and a second end. The first end of the shank is removably coupled to the hole saw and to the pilot bit, and the second end of the shank is configured to be coupled to a power tool. The assembly also includes a sleeve moveable along the shank and a first ball bearing disposed on the sleeve. The first ball bearing engages the hole saw to releasably secure the hole saw to the shank. The assembly includes a second ball bearing disposed on the shank. The second ball bearing engages the pilot bit to releasably secure the pilot bit to the shank. When the sleeve moves toward the second end of the shank, the first and second ball bearings disengage the hole saw and the pilot bit.

A holesaw system comprises a holesaw including a base and a generally cylindrical wall with a proximal end coupled to the base and a distal end with a cutting edge; a pilot drill bit including a front cutting tip, a rear shank portion, and an intermediate portion between the front cutting tip and the rear shank portion; and an arbor coupleable to the holesaw and to the pilot drill bit. The arbor is configured to be operable in a first mode in which the holesaw and the pilot drill bit are rotatable in unison to form a hole in a workpiece and in a second mode in which the pilot drill bit is rotatable independently of the holesaw to remove a plug of material from the holesaw.

A drill bit includes a shank, an intermediate portion with a helical flute, and a multi-stepped tip portion extending along the axis. The tip portion includes a cutting tip with a pair of primary cutting edges extending radially outward from the axis, a plurality of steps each having an elongated portion and a tapered portion tapered outward from the elongated portion relative to the axis. The elongated portions progressively increase in diameter from the cutting tip to the intermediate portion. The elongated portion of each step has an axial relief tapered inward toward the axis. A frontmost elongated portion has a first axial relief at a first angle relative to the central axis and a rearmost elongated portion has a second axial relief at a second angle greater than the first angle. The drill bit may be used as a pilot bit together with a holesaw in a system.

A tool for creating a wall opening. The tool includes a hole saw; and a centering jig having a center axis, where the centering jig is constructed as a centering ring, into which the hole saw can be pushed at least partly, and in that both the hole saw and the centering ring have on their circumference an opening such that this can be pushed transverse to the center axis completely onto a line.

A cutting device in accordance with some example embodiments is provided for use with an arbor assembly. The cutting device includes a blade having a plurality of teeth, and a back plate at a proximal end of the blade. The back plate has an outer end surface in which a plurality of ramp surfaces and pin locking recess are provided. A central through hole extending through the back plate. The ramp surfaces only allow the cutting device to be rotated relative to the arbor assembly in one direction.