Hole-saws are provided herein, and more specifically to hole-saw assemblies and processes having adjustable platters for multiple simultaneous saw components, optional elimination of a guide drill, and the ability to retrieve cores of a sawed work piece before sawing completely through the workpiece. One hole-saw device, may have a motive force; a base plate rotatable by the motive force; cutters; and locking mechanisms to mount the base plate to the cutters.

A drill bit 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 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 hole saw having an internal saw with a circular sidewall including a working end including teeth and a backwall connected to the sidewall. The backwall includes an aperture concentrically located with respect to the circular sidewall for receiving a pilot drill designed to extend beyond the working end of the circular sidewall. The hole saw also has an external saw with a circular sidewall with a greater diameter than the circular sidewall of the internal saw. The circular sidewall of the external saw has teeth and an oppositely located proximal end that includes tangs separated by notches. A base plate is fastened to the circular sidewall of the external saw. The base plate includes a plurality of apertures for fixing the base plate to the backwall of the internal saw and locating the circular sidewalls concentric with respect to each other.

Hole-saws are provided herein, and more specifically to hole-saw assemblies and processes having adjustable platters for multiple simultaneous saw components, optional elimination of a guide drill, and the ability to retrieve cores of a sawed work piece before sawing completely through the workpiece. One hole-saw device, may have a motive force; a base plate rotatable by the motive force; cutters; and locking mechanisms to mount the base plate to the cutters.

Hole-saws are provided herein, and more specifically to hole-saw assemblies and processes having adjustable platters for multiple simultaneous saw components, optional elimination of a guide drill, and the ability to retrieve cores of a sawed work piece before sawing completely through the workpiece. One hole-saw device, may have a motive force; a base plate rotatable by the motive force; cutters; and locking mechanisms to mount the base plate to the cutters.

A rotary cutting unit for a rotary saw has a cross bar and at least one cutting structure, wherein the cutting structure is in contact with the cross bar. The cross bar runs through sleeve holes. The center of gravity of the turning unit is located in an axis of the center of the sleeve holes. The axis is perpendicular to the transverse axis of the crossbar. The rotary saw selectively installs the rotary cutting unit of the corresponding specification, and it can quickly and easily change the aperture of the circular hole to be processed, and with high usability.

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 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.