| Twist Drill Bits | Creates round holes by cutting and evacuating material through helical flutes. | High-speed steel, cobalt alloy steel, or carbide. | General-purpose drilling in wood, plastic, and metal. | Match the bit material and point angle to the workpiece; use a split point to reduce wandering on metal. | Round shank; some models use a hex shank. | Use lower speeds for larger diameters and harder metals; follow the bit manufacturer’s rating. | Use cutting fluid when drilling many metals to reduce heat and extend bit life. |
| Brad-Point Wood Bits | Produces clean, accurately positioned holes in wood using a center point and cutting spurs. | Hardened steel or high-speed steel. | Furniture, cabinetry, softwood, hardwood, and engineered wood. | Choose the diameter, flute length, and bit quality; a sharp center point is important for accurate starts. | Usually round shank. | Moderate to high speed, adjusted for diameter and wood density. | Do not use as a primary choice for steel or masonry. |
| Spade Bits | Rapidly bores relatively large holes through wood with a flat cutting blade. | Carbon steel or hardened tool steel. | Fast rough holes for wiring, plumbing, and construction work. | Select the required diameter and a length suitable for the material thickness. | Usually hex shank for better chuck grip. | Medium to high speed; reduce pressure near breakthrough. | The exit side may splinter, so support the workpiece or drill from both sides. |
| Forstner Bits | Cuts flat-bottomed, clean-sided holes and overlapping holes in wood. | High-speed steel or carbide-tipped steel. | Hinges, recessed fittings, overlapping bores, and precision woodworking. | Consider diameter, cutting-edge design, drilling depth, and whether a flat bottom is required. | Round shank. | Lower speed than small twist bits, especially for large diameters. | Requires a stable drill setup because large sizes generate significant torque. |
| Masonry Bits | Uses a carbide-tipped cutting head to fracture and remove brick, block, concrete, or stone. | Steel body with tungsten-carbide cutting tip. | Mineral-based building materials and anchor holes. | Choose the diameter, length, carbide-tip quality, and compatibility with rotary or hammer drilling. | Round or SDS-type shank, depending on the tool. | Use the tool’s masonry setting and moderate pressure; avoid excessive speed when specified. | Use hammer action only when both the drill and bit are rated for it. |
| Tile and Glass Bits | Creates holes in brittle, hard surfaces with a spear-point or diamond-coated cutting area. | Carbide or diamond abrasive coating. | Ceramic tile, porcelain tile, glass, and some stone surfaces. | Match the bit to the surface hardness and hole diameter; diamond versions are preferred for harder materials. | Usually round or hex shank. | Low speed with light pressure; cooling is often required. | Disable hammer action and prevent the bit from overheating or sliding. |
| Hole Saws | Cuts large-diameter circular openings using a toothed or abrasive cylindrical cup. | Bi-metal steel, carbon steel, carbide grit, or diamond grit. | Large openings for pipes, cables, lights, and hardware. | Choose the cutting diameter, cutting depth, material compatibility, and arbor system. | Arbor with pilot drill; some systems use quick-change interfaces. | Generally lower speed as diameter increases; use the recommended rating. | Clear chips regularly and avoid forcing the saw when it binds. |
| Step Drill Bits | Creates multiple hole diameters with one conical bit containing graduated steps. | High-speed steel, often with a wear-resistant coating. | Thin sheet metal, plastic, electrical boxes, and deburring light-gauge holes. | Check the step-size range, maximum material thickness, and coating for the intended material. | Usually hex shank. | Moderate speed with cutting fluid for metal; avoid excessive feed pressure. | Best for thin stock; thick material can wear the individual steps quickly. |
| Countersink Bits | Creates a conical recess so a flat-head screw can sit flush with or below the surface. | High-speed steel or carbide. | Wood, plastic, and metal screw-hole finishing. | Match the countersink angle and diameter to the screw head and material. | Round or hex shank; some include an integrated pilot drill. | Low to moderate speed with light pressure. | Remove only enough material to seat the fastener without weakening the surface. |
| Screwdriver Bits | Drives screws and fasteners using a shaped tip that matches the fastener recess. | Heat-treated steel, chrome-vanadium steel, or impact-rated alloy steel. | Assembly, installation, repair, and repetitive fastening. | Select the exact tip profile and size; use impact-rated bits for impact drivers. | Commonly 1/4-inch hex shank. | Controlled speed and torque reduce cam-out and fastener damage. | A magnetic holder can improve alignment but does not replace the correct bit size. |
| Nut Setters | Drives hex-head screws, bolts, and nuts with a tubular socket-style head. | Heat-treated alloy steel or impact-rated steel. | Sheet-metal screws, roofing fasteners, and hex-head hardware. | Match the socket size and select an impact-rated version for high-torque tools. | Commonly 1/4-inch hex shank. | Use controlled speed to prevent stripping or over-tightening. | Verify the fastener size before use; metric and inch sizes are not interchangeable. |
| Wire Brushes | Removes rust, scale, paint, burrs, and surface contamination through abrasive wire contact. | Carbon steel, stainless steel, or brass-coated wire. | Surface cleaning, weld preparation, and light deburring. | Choose wire material, brush shape, stiffness, and compatibility with the workpiece. | Shank-mounted wheels, cups, or end brushes. | Stay within the brush’s maximum rated speed. | Wear eye and face protection because wires and debris can be ejected during operation. |
| Sanding Drums and Discs | Removes material, smooths surfaces, and prepares edges using abrasive media. | Aluminum oxide, silicon carbide, zirconia, or diamond abrasive. | Wood shaping, paint removal, plastic finishing, and selected metal work. | Choose abrasive type, grit size, diameter, and backing style for the material and finish. | Mandrel-mounted drums or backing-pad systems. | Use the abrasive’s rated speed; lower speeds help limit heat on plastic and finishes. | Keep the accessory moving to avoid grooves, overheating, or uneven surfaces. |
| Flexible Extension Shafts | Transfers rotary motion to a bit in confined or difficult-to-reach spaces. | Flexible steel shaft with protective polymer housing. | Light-duty fastening and drilling where a straight tool cannot fit. | Check torque capacity, bend radius, length, and compatibility with the bit interface. | Usually 1/4-inch hex input and output. | Use low to moderate speed and avoid sharp bends. | Not suitable for high-torque applications unless specifically rated for them. |