Mortise Drill Bits

EXTRACUT Mortise Drill Bits (also known as square chisel drill bits or hollow chisel bits) specialized woodworking tools designed for creating clean, square-bottomed mortise joints in one pass. Combining the functions of a drill bit and a square chisel, these bits install in dedicated mortising machines or drill press mortising attachments to produce precise rectangular holes for traditional joinery, hinge recesses, and hardware mounting.

Key Features

• Combined Drill + Chisel Action — Central rotating drill bit removes bulk material while the surrounding square chisel shears the corners into a perfect square hole in a single operation.
• High-Carbon Steel Chisel — Heat-treated carbon steel square chisel body (58–60 HRC) provides sharp, durable edges for clean corner shearing across hardwoods.
• HSS Twist Drill Core — Premium HSS center drill bit stays sharp through hundreds of mortises in both softwoods and hardwoods.
• Standard Square Sizes — Available in common mortise dimensions: 1/4", 5/16", 3/8", 1/2", 5/8", 3/4", 7/8", 1" and metric equivalents.
• Quick-Change Design — Standard shank fitting compatible with most benchtop mortising machines (Delta, Jet, Powermatic, etc.).
• Depth Stop Capability — Consistent mortise depth control via machine depth stop or drill bit collar.

Applications

Woodworking shops producing traditional mortise-and-tenon joinery, furniture manufacturing (hinge mortises, lock mortises, hardware recesses), door and window frame fabrication, custom cabinetry, timber framing, and any woodworking application requiring clean, square-bottomed rectangular holes in solid wood or plywood.

Specifications