Tools / Bore and drill

Bore and drill

Tools that make or finish a round hole: awls, gimlets, braces and augers, drills and their bits, hole saws, taps, dies and reamers.

8 tools written

• Brace and bitA hand-cranked boring tool in two parts: a cranked holder, the brace, and a replaceable cutter, the bit. The crank gives leverage and a swept turning circle, and the head lets the user lean body weight along the axis.
• Brad awlA short steel blade with a flat, chisel-edged point set in a handle, pushed and turned into wood to open a small hole for a brad, nail or screw. It parts the wood fibers and removes no material.
• Corded drillA hand-held rotary tool that takes its power from a mains cord and turns a drill bit or driver bit held in a chuck. A patent of 1917 describes its pistol grip and trigger, and its motor has been fed from the wall socket since the earliest electric drills of the 1880s and 1890s.
• Cordless drill-driverA hand-held rotary tool powered by a rechargeable battery that holds a drill bit or driver bit in a chuck and turns it, with an adjustable clutch that lets the same tool bore holes and drive screws. Its pistol-grip form dates from a 1917 patent and its battery power from the 1960s.
• Drill pressA power-driven drilling machine in which a rotating spindle and chuck are mounted on a column above a work table, so that the drill is fed straight down to the work by a lever or hand wheel. It holds the drill square to the table and at a controlled speed and feed.
• Hammer drillA corded or cordless drill with a selector that adds a rapid axial hammering to the rotation of the bit, so that a carbide-tipped bit can bore masonry and concrete. In the common mechanical form two toothed or cam discs ride over each other as the spindle turns.
• Rotary hammerAn electric hammer in which a piston driven by the motor strikes the bit through an air cushion while the bit also turns. Because the blow comes from a striker and not from toothed discs, it can bore larger holes in concrete and, in many models, be set to chisel without rotation. Bits and chisels are held in a slotted quick-change socket of the SDS type.
• Twist drill bitA cylindrical steel cutter with two spiral grooves along its length and a conical point, turned in a drill to cut a round hole. The spiral grooves form the cutting edges and carry the chips out of the hole.