Drill bit GRAPHITE spiral hex shank for wood 20 mm (57H258)

Spiral wood drill bit by GRAPHITE with a 20 mm cutting diameter and hexagonal shank, designed for drilling wood and wood-based materials. The spiral flute geometry clears chips efficiently while the hex shank ensures a secure fit in chucks and quick-change adapters. Intended for bench drills, hand drills and woodworking tasks that require straight, large-diameter holes, this bit delivers stable cutting and reliable hole quality when used at appropriate speeds and with correct feed pressure.

Advantages

The spiral design promotes continuous chip evacuation, reducing clogging and improving drilling speed in soft and medium-density woods. A 20 mm cutting diameter produces accurate, large holes for dowels, bushings and cable passages. The hexagonal shank minimizes slippage in keyless chucks and quick-change holders, enabling faster tool changes and improved torque transfer. The overall geometry supports straight drilling with reduced wandering when pilot guidance or a center punch is used.

Suitable for

• Drilling holes in solid wood, plywood and particleboard
• Producing dowel or bushing holes in furniture assembly
• Making larger access holes for wiring and pipes in carpentry
• Use in bench drills and cordless or corded hand drills with hex chucks

Key specifications

• Cutting diameter: 20 mm
• Shank type: hexagonal
• Flute type: spiral
• Intended material: wood and wood-based panels
• Recommended tools: bench drill, hand drill, quick-change adapter

How to use

Secure the bit in the drill's chuck or quick-change holder so the hex shank seats fully. Select a moderate rotational speed appropriate for a 20 mm wood bit and the density of the material; higher speeds suit softwoods while medium speeds are better for hardwoods and composite boards. Apply steady, even feed pressure without forcing the bit to avoid overheating and splintering. Withdraw the bit periodically on deep holes to clear chips and maintain cutting efficiency. When precision is required, use a center punch or drilling guide to prevent wandering.

Usage recommendations

Use personal protective equipment such as eye protection and a dust mask when drilling. For cleaner entry and exit holes in finished workpieces, consider backing the board with scrap material and clamping the workpiece securely. Clean and inspect the flutes after use to maintain cutting performance.