A damped abrasive cutter having a machine attaching end; an abrasive surface comprising abrasive particles disposed in a binder; a central damping body connecting the machine attaching end to the abrasive surface. The central damping body formed from a synthetic polymer having a Storage Modulus from 1000 MPa to 2500 MPa and a Loss Factor from 0.025 to 0.10.

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 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 method for creating a weep hole is disclosed. The weep hole is drilled in an uncured, concrete, hollow core structural component having one or more external surfaces and one or more internal surfaces. The weep hole is drilled using a drilling apparatus comprising a drill, a rotating drill bit with an internal fluid passageway, a power source, and a pressurized fluid source. Loose, uncured concrete material deposited near the weep hole on the one or more internal surface as a result of drilling the weep hole is removed by releasing pressurized fluid which flows from the pressurized fluid source, through the drill and the rotating drill bit.

[Problem] To protect a leading end part of a drill having a coolant hole which is adapted for drilling a thin diameter or very thin diameter hole in a workpiece. [Solution] A coolant hole 33 is formed in a shank 3 and a shaft body 7 so as to extend through from a rear end surface 31 of the shank 3 to a leading end surface 15 of the shaft body 7 along an axis thereof. A leading end part of the coolant hole 33 is branched into a pair of discharge holes 35, at a position slightly toward a base end relative to the leading end surface 15 of the shaft body 13. The discharge holes 35 extend in the opposite directions, perpendicular to the coolant hole 33, respectively, and open at opposite side surfaces 37, 37 to define discharge ports 39, 39. A leading end opening 41 of the coolant hole 33 is closed by a bottom face 17 of the drill part 9.

A method for creating a weep hole is disclosed. The weep hole is drilled in an uncured, concrete, hollow core structural component having one or more external surfaces and one or more internal surfaces. The weep hole is drilled using a drilling apparatus comprising a drill, a rotating drill bit with an internal fluid passageway, a power source, and a pressurized fluid source. Loose, uncured concrete material deposited near the weep hole on the one or more internal surface as a result of drilling the weep hole is removed by releasing pressurized fluid which flows from the pressurized fluid source, through the drill and the rotating drill bit.

A drilling device for forming an enlarged-diameter hole includes: a guide sleeve with a cylindrical body and a guide to be inserted into a bottomed hole; a slide body that slides in the cylindrical body; and a bit holder provided on the slide body swingably; and a diameter-enlarging bit with a cutting blade. The bit slides between a first position where the cutting blade is separated from a bottom of the bottomed hole and a second position where the cutting blade is closer to the bottom than that at the first position. The guide has: a guide piece that guides the cutting blade to a side part, of the bottomed hole, following an advance of the bit from the first position to the second position; and an opening which allows passage of the bit removed from the bit holder where the bit is at the first position.

It is an object of the present invention to provide a rotary cutting tool that can divide chips at an appropriate size, suppress the incidence of edge chipping and damage attributed to chips to the cutting tool and a workpiece, extend the tool service life with regard to the machining of hard, brittle materials, and improve machining efficiency. The rotary cutting tool includes a hard coat film 3 coated onto a tip end section of a tool body 1 having a chip discharge groove 2. A rake face 6 is concavely provided in a cutting edge-side chip discharge groove formation surface 4 constituting the chip discharge groove 2 of the tool body 1, from a cutting edge 5 and along the cutting edge 5.

Provided is a hole cutting apparatus for forming a hole in a glass laminate substrate including a substrate, an adhesive layer, and the glass layer which are sequentially stacked. The apparatus includes a rotatable body, and a cutter coupled to a lower portion of the body, configured to form a hole in the glass layer by cutting the glass layer and at least a part of the adhesive layer and to deburr a surface of the hole, and including a cutting portion having a cross-sectional area in a horizontal direction that gradually decreases in a downward direction.

A chuck configured to engage a drill bit. The chuck includes a socket body, a first annulus, a second annulus, and a sleeve. The socket body includes a tool end configured to be coupled to a tool and a tool bit end configured to be coupled with the drill bit. The second annulus is selectively movable relative to the first annulus. The sleeve is selectively movable relative to the socket body between a home position in which the second annulus presses upon the drill bit to secure the drill bit to the tool end and a retracted position in which the second annulus is movable relative to the socket body and the drill bit is movable relative to the socket body.