A hole cutter assembly is operable to cut a plurality of different sized diameter holes in a work piece. The hole cutter assembly includes an arbor configured to connect to a power tool for rotation about an axis, a drill bit coupled to the arbor for rotation with the arbor, a first arm moveable relative to the axis, a first cutting blade coupled to the first arm and moveable with the first arm, a second arm moveable relative to the axis, and a second cutting blade coupled to the second arm and moveable with the second arm. The first and second cutting blades are selectively moveable relative to the axis to adjust a cutting diameter of the hole cutter assembly. The drill bit engages the first and second arms to inhibit movement of the first and second cutting blades relative to the drill bit.

A mandrel assembly includes a mandrel, adapter, and bit coupler. The mandrel includes a shank part axially disposed in the mandrel, an adapter receiver, and a coupler receiver. An internal hole runs axially through the adapter. The coupler includes first and second axial sections, and an axial bit connection hole with a polygonal section proximate to an inner side, and a cylindrical section proximate to an opening. An outer wall of the adapter fits with an inner wall of the adapter receiver. An outer wall of the first section fits with an inner wall of the coupler receiver. An outer wall of the second coupler fits with the internal hole of the adapter. The mandrel transmits torque, via the adapter receiver and coupler receiver, to the adapter and then to a hole saw coupled to the adapter, and to the coupler and then to a bit coupled to the coupler.

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.

In one embodiment, a system includes a counterbore drill bit, pre-cut lead rods of predetermined length, and a tapper tool. The counterbore drill bit includes a stop collar to drill counter bored holes with a first hole portion having a first diameter to a first depth below a surface of a material and a second hole portion having a second diameter less than the first to a second depth below the surface. The lead rods are inserted into the counter bored holes. The tapper tool mashes the second end of each lead rod in the one or more counterbored holes to expand and friction fit then in the counter bored holes. The system further includes circular survey tags insertable into the first hole and fasteners with a head and a shaft insertable through a center hole in the survey tags to retain the tags coupled to the lead rods.

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.

The present invention is concerned with twist drills for drilling of composite materials such as carbon fibre reinforced plastic (CFRP) and glass fibre reinforced plastic (GFRP). The present invention proposes that a twist drill (2) is provided with a variable helix having a defined start and finish helix angle, in combination with primary and secondary relief angles such that the drill (2) is adapted to minimise thrust force, particularly when used for drilling fibre-containing composite materials and especially for hand drilling. Start and finish helix angles of 50 and 10; 50 and 30; and 30 and 10 have been shown to provide excellent cutting performance and exit hole quality. A large secondary chisel edge angle (24) has also been found to contribute to excellent performance with composite materials, including stack machining.

A hole saw arbor with mechanically automated plug removal to automatically remove the center plug of debris following drilling with the hole saw. A slidable collar is placed in an upper position on a threaded shaft to drill with the hole saw, and slid to a lower position on the threaded shaft for automated function of an ejection plate to rise within the hole saw to slowly eject a plug of removed material.

A hole cutter assembly is operable to cut a plurality of different sized diameter holes in a work piece. The hole cutter assembly includes an arbor configured to connect to a power tool for rotation about an axis, a drill bit coupled to the arbor for rotation with the arbor, a first arm moveable relative to the axis, a first cutting blade coupled to the first arm and moveable with the first arm, a second arm moveable relative to the axis, and a second cutting blade coupled to the second arm and moveable with the second arm. The first and second cutting blades are selectively moveable relative to the axis to adjust a cutting diameter of the hole cutter assembly. The drill bit engages the first and second arms to inhibit movement of the first and second cutting blades relative to the drill bit.

A hole cutter assembly is operable to cut a plurality of different sized diameter holes in a work piece. The hole cutter assembly includes an arbor configured to connect to a power tool for rotation about an axis, and a body coupled to the arbor for rotation with the arbor. The body defines an aperture. The hole cutter assembly includes a drill bit removably received in the aperture of the body for rotation with the arbor, an arm moveably coupled to the body, and a cutting blade coupled to the arm and moveable with the arm relative to the body. The arm is moveable relative to the body to adjust a cutting diameter of the hole cutter assembly when the drill bit is not received within the aperture. The arm is fixed relative to the body when the drill bit is received within the aperture.

A tool that cuts a hole for a single or double electric gang switch box. By having four blades, all cutting at the same time and in the shape of the switch box, a more accurate and appropriately placed hole may be provided. The hole saw may be configured with two centering drills so the tool is guided into the cut. An eccentric drive mechanism converts a rotary drive into reciprocating movement of perpendicularly opposed pairs of blades to cut a rectangular opening.