Countersink Bits

Countersink bits create a conical recess so screw heads sit flush with or below the surface.  Combined countersink and pilot drill bits save time when installing screws in timber and sheet metal.

What are countersink bits used for?
Countersink bits are used to create a conical recess in the surface of a material so that a screw head sits flush or below the surface. This is especially useful in:

• Woodworking and cabinetry

• Joinery and furniture assembly

• Metal and plastic fastening where flush finishes are needed
  They’re commonly used in combination with pilot hole drilling to prevent splitting and improve the appearance of fastened surfaces.

What types of countersink bits are available?

• Single countersink bits – cut only the chamfer for screw heads

• Combination bits – drill the pilot hole and countersink in one pass

• Adjustable depth stop bits – allow for repeatable, uniform countersinks

• Materials:

  • High-speed steel (HSS) – general use

  • Carbon steel – for softwoods and plastics

  • Carbide-tipped – for hardwoods, laminates, or metal

  • Titanium-coated – for longer life and heat resistance

How do I choose the correct countersink bit?
Consider:

• Screw size – match the bit angle (typically 82° or 90°) and hole size to your screws

• Material being drilled – use sharper, harder bits (like carbide or titanium) for harder materials

• Drill type compatibility – check shank size (round or hex) to suit your chuck

• Finish quality – combination bits reduce steps, while adjustable types provide cleaner, more accurate results for visible joints