Drill Bit Irwin spiral hex shank for wood 20 mm (1922001)

The Irwin spiral hex shank drill bit for wood with a 20 mm cutting diameter is built for precise and stable drilling in timber. Its spiral twist design improves chip evacuation to maintain clean holes and steady penetration in both softwoods and hardwoods. The hexagonal shank ensures a reliable grip in chucks and quick-change adapters, reducing slippage during heavy or repetitive drilling tasks.

Advantages

The spiral flute accelerates chip removal to prevent clogging and ensures consistent cutting performance. The 20 mm diameter delivers a large, accurate bore suitable for dowels, conduit passages, and joinery fittings. The hex shank enhances torque transfer and compatibility with impact drivers and quick-change holders, improving stability and reducing wobble. The bit is designed to produce smooth hole edges and minimize tear-out when used with appropriate feed rates and support.

Suitable for

• Drilling clean through-holes and stopped holes in softwood and hardwood
• Carpentry and joinery fittings such as dowel and hinge installation
• Creating passages for wiring, pipes or conduits in wooden workpieces
• Workshop and on-site woodworking with corded or cordless drivers

Key specifications

• Cutting diameter: 20 mm
• Shank type: hexagonal shank for improved grip
• Tip and flute: spiral twist geometry for chip evacuation
• Material suitability: softwood and hardwood
• Typical applications: through-holes, dowel holes, conduit passages

How to use

Select a compatible chuck or quick-change adapter that accepts hex shanks and secure the bit firmly. Mark the drilling position and, if precision is required, use a center punch or pilot mark to prevent walking. Start drilling at moderate speed to establish the hole, then apply steady forward pressure while allowing the spiral flutes to carry chips away. Withdraw the bit occasionally on deep holes to clear chips and prevent clogging. For cleaner entry and exit edges, support the workpiece and consider backing material or reducing feed speed as the bit breaks through.

Usage recommendations

Use appropriate personal protective equipment, secure the workpiece before drilling, and match drilling speed to wood species—lower speeds for hard timber and higher speeds for softwood. Inspect the bit for wear and replace when cutting becomes dull to maintain hole quality and reduce the risk of overheating or damage.