Drill bit DeWalt DT4921-QZ, 650 mm length, for metal, pack of 10

DeWalt DT4921-QZ is a 650 mm long specialist drill bit designed for metalworking tasks that require extended reach. Supplied as a pack of 10, this long-reach bit is intended for drilling through thick sheets, structural members and assemblies where standard-length bits are not sufficient. The geometry and tip design improve penetration and hole quality when working with high-strength alloys and a wide range of metals.

Advantages

The 650 mm length affords access to deep or hard-to-reach drilling positions without the need for extensions. A no-walk tip reduces wandering at the start of drilling, enabling more accurate hole placement on materials with uneven surfaces. Recessed cutting wings produce cleaner, burr-free holes and reduce the need for secondary deburring operations. Supplied in a pack of 10, the kit supports repetitive workshop or onsite tasks and reduces downtime for bit changes.

Suitable for

• Portable and stationary drilling of steels and metals with high alloy content
• Drilling materials with tensile strength up to 1100 N/mm²
• Deep through-holes in structural components and metal assemblies
• Workshop and professional maintenance tasks requiring long-reach bits

Key specifications

• Overall length: 650 mm
• Intended material: metal and high-alloy steels
• Tip type: no-walk / self-centering style for improved penetration
• Cutting feature: recessed cutting wings for reduced burrs
• Pack quantity: 10 pieces

How to use

Secure the drill bit in a compatible chuck or holder rated for long-shank tooling and verify straight alignment before starting. Use appropriate drill speeds, cutting fluid and feed pressure for the specific metal being drilled to manage heat and tool wear. Begin drilling with light pressure to allow the no-walk tip to locate the hole, then increase to a steady feed once the bit is established. Withdraw periodically for chip clearance on deep holes and ensure the workpiece is firmly clamped to prevent movement.

Usage recommendations

For best results, use coolant or cutting oil when drilling high-alloy steels and maintain moderate speeds to extend bit life. Verify chuck capacity and balance when using long-length bits and follow safety procedures for clamping and personal protection.